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Bicuspid Aortic Valve – An important incidental PoCUS finding?

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Bicuspid Aortic Valve – An important incidental PoCUS finding?

Medical Student Pearl

 

Khoi Thien Dao

MD Candidate – Class of 2023

Dalhousie Medicine New Brunswick

Reviewed by: Dr. David Lewis

Case:

A 58-year-old male presents to Emergency Department with sudden onset of chest pain that is radiating to the back. He was also having shortness of breath at the same time of chest pain. The patient later reveals that his past medical history only consists of “bicuspid valve”, and he takes no medication. On examination, he was uncomfortable, but no signs of acute distress. His respiratory and cardiac exam were unremarkable for reduced air sound, adventitious sound, heart murmur, or extra heart sound. ECG was normal and initial cardiac markers were within normal range. His chest x-ray is normal.

You are aware that with his medical presentation and a history of bicuspid aortic valve, you need to consider associated concerning diagnosis (aortic root aneurysm and aortic dissection) within the differential (myocardial infarct, congestive heart failure, pneumonia, etc.).

Bicuspid Aortic Valve

Bicuspid aortic valve is one of the most common types of congenital heart disease that affects approximately one percent of population. There is a strong heritable component to the disease. Bicuspid aortic valve occurs when two leaflets fused (commonly right and left coronary leaflets) and form a raphe, a fibrous ridge1. The fusion of the leaflets can be partial, or complete, with the presence or absence of a raphe1. Bicuspid aortic valve disease is associated with increasing risks for valve calcification, which lead to aortic stenosis or regurgitation secondary to premature degeneration1. This congenital heart defect is also a well-known risks factor for aortic dissection and aortic dilatation. Reports have estimated prevalence of aortic dilation in patients with bicuspid aortic valve ranging between 20 to 80 percent, and that the risks of aortic dilation increase with age2. Increases risk of aortic dilatation in bicuspid valve disease also leads to a significantly greater risk for aortic dissection2.3.

The majority of patients with bicuspid aortic valve are asymptomatic with relatively normal valve function and therefore can remain undiagnosed for many years. However, most patients with bicuspid aortic valve will develop complications and eventually require valve surgery within their lifetime. Early diagnosis, while asymptomatic, can enable close follow-up for complications and early intervention with better outcomes. However, asymptomatic individuals are rarely referred for echocardiography.

With increasing use of cardiac PoCUS by Emergency Physicians, there are two scenarios where increased awareness of the appearance of bicuspid aortic valve and its complications may be of benefit.

  1. Known bicuspid aortic valve patients presenting with possible associated complications
  2. Undiagnosed bicuspid aortic valve patients presenting with unrelated symptoms undergoing routine cardiac PoCUS

This clinical pearl provides a review of the clinical approach to bicuspid aortic valve and its associated complications and provides guide to enhancing clinical assessment with PoCUS.

Clinical Approach:

Although bicuspid aortic valve commonly presents as asymptomatic, a detailed focused cardiac history can assess for clinical signs and symptoms related to valve dysfunction and its associated disease, such as reduced exercise capacity, angina, syncope, or exertional dizziness1. Information about family history with relation to cardiac disease is essential for a clinician’s suspicion of heritable cardiovascular disease. Red flag symptoms that shouldn’t be missed such as chest pain, back pain, hypertensive crisis, etc. should be specifically identified. They are indicators for possible emergent pathologies that should not be missed (for example: acute MI, aortic dissection, ruptured aortic aneurysm, etc.)

Physical examination findings in patients with bicuspid aortic valve include, but not limited to, ejection sound or click at cardiac apex/base, murmurs that have features of crescendo-decrescendo or holosystolic. Clinical signs of congestive heart failure such as dyspnea, abnormal JVP elevation, and peripheral edema may also be present.

Core Cardiac PoCUS:

With cardiac PoCUS, it is important to obtain images from different planes and windows to increase the complexity of the exam and to be able to be confidently interpreting the exam. There are four standard cardiac view that can be obtained: parasternal short axis (PSSA), parasternal long axis (PSLA), subxiphoid (sub-X), and apical 4-chamber view (A4C). Each cardiac view has specific benefits.

Parasternal Long Axis

With the PSLA, the phased-array transducer is placed to the left sternum at 3rd or 4th intercostal with transducer orientation pointing toward patient’s right shoulder. Key structures that should be seen are Aortic Valve (AV), Mitral Valve (MV), Left Ventricle (LV), pericardium, Right Ventricle (RV), Left Ventricular Outflow Tract (LVOT), and portion of ascending and descending aorta8. It is primarily used to assess left ventricular size and function, aortic and mitral valves, left atrial size8. Furthermore, pericardial effusions and left ventricular systolic function can be assessed.

Parasternal Long Axis

 

Parasternal Short Axis

Using the same transducer position as the PSLA the transducer can be centered to the mitral valve and rotated 90 degrees clockwise to a point where the transducer marker points to patient’s left shoulder to obtain the PSSA. With this orientation, one can assess for global LV function and LV wall motion8. Furthermore, with five different imaging planes that can be utilized with this view, aortic valve can be visualized in specific clinical contexts.

Parasternal Short Axis

 

Apical 4-Chamber

The apical 4-chamber view is generated by placing the transducer at the apex, which is landmarked just inferolateral to left nipple in men and underneath inferolateral of left breast in women. This view helps the clinician to assess RV systolic function and size relative to the LV8.

Apical 4-Chamber

 

Subxiphoid

The subxiphoid view can be visualized by placing a transducer (phased-array or curvilinear) immediately below the xiphoid process with the transducer marker points to patient’s right. The movements of rocking, tilting, and rotation are required to generate an optimal 4-chamber subcostal view. A “7” sign, which consists of visualizing the border between liver and pericardium, the septum, and the RV and LV that looks like number 7. This view allows user to assess RV functions, pericardial effusion, and valve functions8. In emergency setting, it can be used for rapid assessments in cardiac arrest, cardiac tamponade, and global LV dysfunction8.

From –  the PoCUS Atlas

Subxiphoid labelled

 

7 Sign

PoCUS Views for Aortic Valve Assessment

In assessing the aortic valve, the PSSA and PSLA can be best used to obtain different information, depending on clinical indications. Both views can be used to assess blood flows to assess stenosis or regurgitation. However, the PSLA view includes the aorta where clinician can look for aortic valve prolapse or doming as signs of stenosis and its complications, like aortic dilatation. On the other hand, PSSA are beneficial when assessing the aortic valve anatomy.

Parasternal Long Axis

From PoCUS 101

Parasternal Short Axis

From – the PoCUS Atlas

PoCUS Appearance of Normal Aortic Valve (Tricuspid) vs Bicuspid Aortic Valve

With PSSA view, the normal aortic valve will have three uniformly leaflets that open and form a circular orifice during most of systole. During diastole, it will form a three point stars with slight thickening at central closing point. The normal aortic valve is commonly referred to as the Mercedes Benz sign.

Parasternal Short Axis – Normal Tricuspid AV – Mercedes Benz Sign and 3 cusp opening

Pitfall

However, the Mercedes Benz Sign sign can be misleading bicuspid valve disease when three commissure lines are misinterpreted due to the presence of a raphe. A raphe is a fibrous band formed when two leaflets are fused together. It is therefore important to visualize the aortic valve when closed and during opening, to ensure all 3 cusps are mobile. Visualization of The Mercedes Benz sign is not enough on its own to exclude Bicuspid Aortic Valve.

Apparent Mercedes sign when AV closed due to presence of raphe. Fish mouth appearance of the same valve when open confirming bicuspid aortic valve

Bicuspid Aortic Valve

Identification requires optimal valve visualization during opening (systole). Appearance will depend on the degree of cusp fusion. In general a ‘fish mouth’ appearance is typical for bicuspid aortic valve.

Parasternal Short Axis – Fish Mouth Opening – Fusion L & R Coronary Cusps – Bicuspid Aortic Valve

In the parasternal long axis view the aortic valve can form a dome shape during systole, and prolapse during diastole, rather than opening parallel to the aorta. This is called systolic doming. Another sign that can be seen in PSLA view is valve prolapse, when either right or non-coronary aortic valve cusps showed backward bowing towards the left ventricle beyond the attachment of the aortic valve leaflets to the annulus. This can be estimated by drawing a line joining the points of the attachment.

Systolic doming

 

Diastolic prolapse and systolic doming

 

 

 

PoCUS Appearance of the Complications of Bicuspid Valve Disease

In patients presenting with chest/back pain, shock or severe dyspnea who have either known or newly diagnosed bicuspid valve disease, PoCUS assessment for potential complications can be helpful in guiding subsequent management.

Complications of bicuspid aortic valve include aortic dilatation at root or ascending (above 3.8cm) and aortic dissection 5-9.

Dilated aortic root, from – sonomojo.com

Aortic root dilatation – Normal maximum = 40mm

 

Aortic root dilatation with dissection

Valve vegetations or signs of infective endocarditis are among the complications of severe bicuspid valve5-9

Aortic valve vegetations

General Management of Patients with Bicuspid Valve in the Emergency Department

Management of bicuspid aortic valve disease is dependent on the severity of the disease and associated findings.

For a patient with suspicious diagnosis of bicuspid valve disease, a further evaluation of echocardiography should be arranged, and patient should be monitored for progressive aortic valve dysfunction as well as risk of aortic aneurysm and dissection. Surgical intervention is indicated with evidence of severe aortic stenosis, regurgitation, aneurysm that is > 5.5cm, or dissection1.

How accurate is PoCUS for Aortic Valve assessment?

Bicuspid aortic valve disease is usually diagnosed with transthoracic echocardiography, when physical examination has revealed cardiac murmurs that prompt for further investigation. However, patients with bicuspid valve disease frequently remain asymptomatic for a prolonged periods. Michelena et al. (2014) suggested that auscultatory abnormalities account for 60 to 70% diagnostic echocardiograms for BAV in community10.

While there are no published studies on the utility of PoCUS for the diagnosis of bicuspid aortic valve, there are studies on the use of PoCUS as part of the general cardiac exam. Kimura (2017) published a review that reported early detection of cardiac pathology when PoCUS was used as part of the physical exam 9. Abe et al. (2013) found that PoCUS operated by expert sonographer to screen for aortic stenosis has a sensitivity of 84% and a specificity of 90% in 130 patients 11. In another study by Kobal et al. (2004), they found that PoCUS has a specificity of 93% and sensitivity of 82% in diagnosing mild regurgitation12.

There are also limitations of using PoCUS to assess for bicuspid aortic valve disease, or valve disease in general. Obtaining images from ultrasound and interpretation are highly dependent on user’s experiences to assess for the valve9. Furthermore, research is needed to investigate the use of PoCUS in lesser valvular pathology.

 

When a new diagnosis of bicuspid aortic valve is suspected, a formal echocardiogram should be arranged, and follow-up is recommended.

Summary 

  • Bicuspid aortic valve is often asymptomatic and undiagnosed until later in life
  • Patients with known bicuspid aortic valve disease are closely followed and may require surgical intervention in the event of complications
  • Diagnosis of bicuspid aortic valve requires careful visualization of valve closing and opening during diastole and systole
  • The increased use of PoCUS by Emergency Physicians as an adjunct to cardiac examination may result in increased diagnosis of bicuspid  aortic valve. These may be related to the presentation or incidental findings
  • In patients presenting to the Emergency Department with known or newly diagnosed bicuspid aortic valve disease, consider if a complication is related to their presentation
  • In patient with incidental finding of bicuspid aortic valve disease refer for cardiology follow up

 

References

  1. Braverman, A. C., & Cheng, A. (2013). The bicuspid aortic valve and associated aortic disease. Valvular heart disease. Philadelphia: Elsevier, 179-218.
  2. Verma, S., & Siu, S. C. (2014). Aortic dilatation in patients with bicuspid aortic valve. N Engl J Med, 370, 1920-1929.
  3. Della Corte, A., Bancone, C., Quarto, C., Dialetto, G., Covino, F. E., Scardone, M., … & Cotrufo, M. (2007). Predictors of ascending aortic dilatation with bicuspid aortic valve: a wide spectrum of disease expression. European Journal of Cardio-Thoracic Surgery, 31(3), 397-405.
  4. Tirrito, S. J., & Kerut, E. K. (2005). How not to miss a bicuspid aortic valve in the echocardiography laboratory. Echocardiography: A Journal of Cardiovascular Ultrasound and Allied Techniques, 22(1), 53-55.
  5. Baumgartner, H., Donal, E., Orwat, S., Schmermund, A., Rosenhek, R., & Maintz, D. (2015). Chapter 10: Aortic valve stenosis. The ESC textbook of cardiovascular imaging. European Society of Cardiology.
  6. Fowles, R. E., Martin, R. P., Abrams, J. M., Schapira, J. N., French, J. W., & Popp, R. L. (1979). Two-dimensional echocardiographic features of bicuspid aortic valve. Chest, 75(4), 434-440.
  7. Shapiro, L. M., Thwaites, B., Westgate, C., & Donaldson, R. (1985). Prevalence and clinical significance of aortic valve prolapse. Heart, 54(2), 179-183.
  8. Gebhardt, C., Hegazy, A.F., Arntfield, R. (2015). Chapter 16: Valves. Point-of-Care Ultrasound. Philadelphia: Elsevier, 119-125.
  9. Kimura, B. J. (2017). Point-of-care cardiac ultrasound techniques in the physical examination: better at the bedside. Heart, 103(13), 987-994.
  10. Michelena, H. I., Prakash, S. K., Della Corte, A., Bissell, M. M., Anavekar, N., Mathieu, P., … & Body, S. C. (2014). Bicuspid aortic valve: identifying knowledge gaps and rising to the challenge from the International Bicuspid Aortic Valve Consortium (BAVCon). Circulation, 129(25), 2691-2704.
  11. Abe, Y., Ito, M., Tanaka, C., Ito, K., Naruko, T., Itoh, A., … & Yoshikawa, J. (2013). A novel and simple method using pocket-sized echocardiography to screen for aortic stenosis. Journal of the American Society of Echocardiography, 26(6), 589-596.
  12. Kobal, S. L., Tolstrup, K., Luo, H., Neuman, Y., Miyamoto, T., Mirocha, J., … & Siegel, R. J. (2004). Usefulness of a hand-carried cardiac ultrasound device to detect clinically significant valvular regurgitation in hospitalized patients. The American journal of cardiology, 93(8), 1069-1072.
  13. Le Polain De Waroux, J. B., Pouleur, A. C., Goffinet, C., Vancraeynest, D., Van Dyck, M., Robert, A., … & Vanoverschelde, J. L. J. (2007). Functional anatomy of aortic regurgitation: accuracy, prediction of surgical repairability, and outcome implications of transesophageal echocardiography. Circulation, 116(11_supplement), I-264.
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Management of Supraventricular Tachycardia (SVT) in Pregnancy

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Management of Supraventricular Tachycardia (SVT) in Pregnancy

Medical Student Clinical Pearl

 

Tyson Fitzherbert, DMNB Class of 2024

Reviewed by Dr. Luke Taylor and Dr. David Lewis

 

Case:

A 30-year-old pregnant (32 weeks) female presents to the emergency department with palpitations and chest discomfort. On ECG they are diagnosed with supraventricular tachycardia, a narrow complex arrythmia – how would you proceed?

 

Introduction:

Pregnant women have a higher incidence of cardiac arrhythmias. The exact mechanism of increased arrhythmia burden during pregnancy is unclear, but has been attributed to hemodynamic, hormonal, and autonomic changes related to pregnancy. A common arrhythmia in pregnancy is supraventricular tachycardia (SVT). SVT is a dysrhythmia originating at or above the atrioventricular (AV) node and is defined by a narrow complex (QRS < 120 milliseconds) at a rate > 100 beats per minute (bpm). The presentations of SVT in pregnancy are the same as the nonpregnant state and include symptoms of palpitations that may be associated with presyncope, syncope, dyspnea, and/or chest pain. Diagnosis is confirmed by electrocardiogram (ECG).

 

Figure 1: Rhythm strip demonstrating a regular, narrow-complex tachycardia, or supraventricular tachycardia (SVT).

In general, the approach to the treatment of arrhythmias in pregnancy is similar to that in the nonpregnant patient. However, due to the theoretical or known adverse effects of antiarrhythmic drugs on the fetus, antiarrhythmic drugs are often reserved for the treatment of arrhythmias associated with clinically significant symptoms or hemodynamic compromise. Below is a detailed description of the management of SVT in pregnancy.

 

Management:

Figure 2: Treatment algorithm for SVT in pregnancy.

 

General Considerations:

  • Non‐pharmacological treatment including vagal manoeuvres such as carotid massage and Valsalva manoeuvre are well tolerated and aid in management.
  • Intravenous adenosine can be used in all three trimesters, including labor.
  • Electrical cardioversion is an effective treatment method for hemodynamically unstable or drug-refractory patients, which has proven to be safe in all three trimesters, including labor. There are some examples of this leading to pre-term labor in the third trimester.
  • AV nodal blocking agents and anti-arrhythmic agents may be considered for cardioversion; see table below for effects in pregnancy and breast feeding.

 

 

Case Continued:

A modified Valsalva manoeuvre is performed with resolution to sinus rhythm after 2 attempts. The patient is discharged with OBGYN follow-up.

https://sjrhem.ca/modified-valsalva-maneuver-in-the-treatment-of-svt-revert-trial/

 

Further Reading

References:

  1. Patti L, Ashurst JV. Supraventricular Tachycardia. [Updated 2022 Aug 8]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www-ncbi-nlm-nih-gov.ezproxy.library.dal.ca/books/NBK441972/
  2. UpToDate – https://www.uptodate.com/contents/supraventricular-arrhythmias-during-pregnancy#H11407709
  3. Ibetoh CN, Stratulat E, Liu F, Wuni GY, Bahuva R, Shafiq MA, Gattas BS, Gordon DK. Supraventricular Tachycardia in Pregnancy: Gestational and Labor Differences in Treatment. Cureus. 2021 Oct 4;13(10):e18479. doi: 10.7759/cureus.18479. PMID: 34659918; PMCID: PMC8494174. https://www-ncbi-nlm-nih-gov.ezproxy.library.dal.ca/pmc/articles/PMC8494174/
  4. Ramlakhan KP, Kauling RM, Schenkelaars N, et al, Supraventricular arrhythmia in pregnancy, Heart 2022;108:1674-1681. https://heart.bmj.com/content/early/2022/01/26/heartjnl-2021-320451#T2
  5. Goyal A, Hill J, Singhal M. Pharmacological Cardioversion. [Updated 2022 Jul 25]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www-ncbi-nlm-nih-gov.ezproxy.library.dal.ca/books/NBK470536/
  6. Vaibhav R. Vaidya, Nandini S. Mehra, Alan M. Sugrue, Samuel J. Asirvatham, Chapter 60 – Supraventricular tachycardia in pregnancy, Sex and Cardiac Electrophysiology. https://www-sciencedirect-com.ezproxy.library.dal.ca/science/article/pii/B9780128177280000607

 

 

 

 

 

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Murmurs for the Learners: An approach to pediatric heart murmurs

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Murmurs for the Learners: An approach to pediatric heart murmurs – A Medical Student Clinical Pearl

Luke MacLeod, Med IV

DMNB Class of 2022

Reviewed by Dr. Tushar Pishe

Copyedited by Dr. Mandy Peach

Case:

You are a senior medical student working in the emergency department and are asked to see Charlie, a 3-year-old boy who had a fall.  He is accompanied by his uncle Kevin, who gives you the history.  About one hour ago, Charlie was climbing onto a chair when he fell off and hit his head.  The chair was only a few feet off the ground and the floor was covered with a rug.  Charlie cried for several minutes after the fall, but there was no loss of consciousness or vomiting following the event.

Kevin tells you that Charlie is a healthy boy with no known medical issues or surgical history. There have been no concerns with his growth or development thus far.  He has no allergies, does not take any medications, and is up to date on his immunizations.  Kevin is unable to tell you much about Charlie’s family history.  He recently adopted Charlie, whose biological parents are no longer involved.

On exam, you observe an active and responsive 3-year-old.  He is afebrile with stable vital signs.  He has normal colour and shows no signs of respiratory distress.  There is a small bump on the top of his head, but no other injuries are noted.  His neurological exam reveals no focal neurological deficits.  To complete the exam, you feel his abdomen, which is soft and non-tender with no organomegaly, and auscultate his heart and lungs.  His lungs are clear with no crackles or wheeze. On auscultation of the heart, you detect a soft, non-radiating systolic murmur that seems to go away with inspiration.

You are reassured from the history and exam that Charlie’s head injury was very minor and that no further investigations or interventions are necessary, but you wonder about the significance of his heart murmur.

 

What is a heart murmur?

 

A heart murmur is an additional sound, often described as whooshing or blowing noise, heard between heart beats that is generated by turbulent blood flow in or near the heart.1,2  Heart murmurs are very common, with up to 90% of children having one either during infancy or later in childhood.  However, less than 1% of these murmurs are due to congenital heart disease.3  If the heart murmur is related to a serious underlying condition, the child may have signs or symptoms such as cyanosis, cough, shortness of breath, or light-headedness.1  Most murmurs are asymptomatic, but the absence of symptoms does not always mean that the murmur is benign.3 In some cases a murmur may be the only sign of an underlying heart condition.4

 

How to describe a murmur

 

Before picking up your stethoscope, you’ll want to make sure you have clean ear canals so you can pick up subtle murmurs.  The characteristics use to describe a murmur can be remembered with the pneumonic Q-TIP ROLS (note: this is not a recommendation to clean your ears with cotton swabs).

 

Quality

The quality of a murmur can be described as harsh, blowing, musical, rumbling, or vibrating.3

 

Timing

Timing describes when the murmur occurs in the cardiac cycle.  A systolic murmur occurs between S1 and S2.  These can be further categorized into four sub-types:

  • Early systolic: heard with or immediately after S1 and ends about halfway through systole.
  • Mid-systolic/systolic ejection murmur: heard midway between S1 and S2. Increases then decreases in volume (crescendo-decrescendo).
  • Mid-to-late systolic: heard about halfway through systole and ends before S2
  • Holosystolic/pansystolic: heard throughout systole.

Click here to listen to a holosystolic murmur: https://www.youtube.com/watch?v=MzORJbyHTT0

 

A diastolic murmur occurs between S2 and S1.  These can be further categorized into three sub-types:

  • Early diastolic: a high-pitched murmur heard with or immediately after S2.
  • Mid-diastolic: heard soon after S2 and ends before S1.
  • Late diastolic/presystolic: heard just before S1.

 

A continuous murmur is heard throughout the cardiac cycle.3

 

Intensity

A grading system from 1-6 is used to describe a murmur’s intensity, with higher values representing greater volumes.3  The following table details what each grade indicates:5

Pitch

A murmur can have low, medium, or high pitch.  High pitch murmurs are best detected using the diaphragm of the stethoscope, while low pitch murmurs are easier to hear using the bell.3

 

Radiation

This is the furthest point from the location (see below) where the murmur can still be detected.3

 

Other sounds

S3: heard in early diastole (shortly after S2).  S3 can be present in hyperdynamic states or with a large VSD.  This sound is best heard with the bell over the apex (for blood flow to the left ventricle) or the lower left sternal border (for blood flow to the right ventricle). When an S3 is present, the heart beat cadence is often described using the word “Kentucky” where “Ken” is S1, “tuc” is S2, and “ky” is S3.5

 

S4: heard late in diastole (just before S1) when there is turbulent blood flow into a stiff ventricle, such as in hypertrophic cardiomyopathy, myocardial dysfunction, semilunar valve stenosis, or tachycardia-induced cardiomyopathy.  S4 is best heard with the bell and is a pathologic exam finding.  When an S4 is present, the heart beat cadence is often described using the word “Tennessee,” where “Ten” is S4, “nes” is S1, and “see” is S2.5

 

Click below to listen to S3 and S4 heart sounds

https://www.youtube.com/watch?v=o8eqYHCy7dw

 

Ejection clicks

These are high pitch sounds that are often generated by abnormal heart valves.  The affected valve is determined based on the location, timing, and nature of the click as shown in the table below:5

Pericardial friction rub

A coarse grinding sound heard with pericarditis. This is best heard along the left sternal border.5

 

Location

This is the point where the murmur is most easily heard.3

 

Shape

Shape describes a murmur’s volume pattern. A few examples are shown below:6

What are the characteristics of benign and pathological murmurs?

 

Some red flag characteristics of pathologic murmurs are listed below.4,7

  • Holosystolic
  • Diastolic
  • Grade 3 or higher
  • Harsh quality
  • Systolic click
  • Max intensity at upper left sternal border
  • Abnormal S2
  • Greater intensity with standing

 

Characteristics of benign murmurs can be remembered using The Seven S’s.4,8

  • Systolic
  • Soft
  • Short (not holosystolic)
  • Small (non-radiating)
  • Sweet (not harsh)
  • Single (no clicks or gallops)
  • Sensitive (changes with position or respiration)

 

Click below to listen to an innocent heart murmur

https://www.youtube.com/watch?v=uFyWHPfrRak

 

Here are some examples to practice differentiating innocent from pathological murmurs:

https://teachingheartauscultation.com/pediatric-murmur-recognition-program-intro

 

What are some of the more common pediatric heart murmurs?

 

Innocent9

  • Classic vibratory parasternal-precordial stills murmur
  • Pulmonary ejection murmur
  • Systolic murmur of pulmonary flow in neonates
  • Venous hum
  • Carotid bruit

 

Pathologic4

  • Ventricular septal defect
  • Atrial septal defect (example: https://www.youtube.com/watch?v=W8gg2S-mvSQ)
  • Patent ductus arteriosus
  • Teratology of Fallot
  • Pulmonary stenosis
  • Coarctation of the aorta
  • Aortic stenosis
  • Transposition of the great arteries

 

Next steps

 

In patients with a heart murmur and an abnormal chest X-ray or ECG, an echocardiogram is indicated.  The echocardiogram is the gold standard test to diagnose congenital heart defects.  While the chest X-ray and ECG are low cost tests and can help rule out other diagnoses, they are not particularly useful in identifying the cause of a heart murmur. 3

An innocent heart murmur in an asymptomatic patient with an otherwise normal exam does not require referral to cardiology.  However, the patient should be followed by their family physician to monitor the murmur.

Patients who are symptomatic, have a pathologic murmur, and/or have other concerning exam findings should be referred to a pediatric cardiologist.10

 

Case Conclusion

 

Charlie’s heart murmur lacked any of the red flag characteristics.  It was soft (grade 2) systolic murmur that did not radiate and changed with inspiration, which are all reassuring signs.  He was also asymptomatic and had an otherwise normal exam.

You explain to Kevin that Charlie looks well and that there are no signs of serious head trauma.  You mention that you did notice a heart murmur that is likely benign.  Charlie does not need to see a specialist, but you recommend that he have a follow up appointment with his family doctor in the next few weeks to monitor the heart murmur.

 

 

References:

  1. Heart Pulse Sound Wave Icon Stock Vector – Illustration of blood, healthcare: 91331428. Accessed November 19, 2021. https://www.dreamstime.com/stock-illustration-heart-pulse-sound-wave-icon-background-image91331428
  2. Heart Murmur | NHLBI, NIH. Accessed November 18, 2021. https://www.nhlbi.nih.gov/health-topics/heart-murmur
  3. Heart murmurs: MedlinePlus Medical Encyclopedia. Accessed November 18, 2021. https://medlineplus.gov/ency/article/003266.htm
  4. Pediatric Heart Murmurs: Evaluation and management in primary care. Accessed November 18, 2021. https://oce-ovid-com.ezproxy.library.dal.ca/article/00006205-201103000-00006/HTML
  5. Frank JE, Jacobe KM. Evaluation and Management of Heart Murmurs in Children. Am Fam Physician. 2011;84(7):793-800.
  6. Approach to the infant or child with a cardiac murmur – UpToDate. Accessed November 18, 2021. https://www.uptodate.com/contents/approach-to-the-infant-or-child-with-a-cardiac-murmur?search=heart%20murmurs&source=search_result&selectedTitle=1~150&usage_type=default&display_rank=1
  7. Physical Examination – Textbook of Cardiology. Accessed November 18, 2021. https://www.textbookofcardiology.org/wiki/Physical_Examination
  8. Pediatric Heart Murmur Recognition Program intro. Teaching Heart Auscultation to Health Professionals. Accessed November 19, 2021. https://teachingheartauscultation.com/pediatric-murmur-recognition-program-intro
  9. Bronzetti G, Corzani A. The Seven “S” Murmurs: an alliteration about innocent murmurs in cardiac auscultation. Clin Pediatr (Phila). 2010;49(7):713. doi:10.1177/0009922810365101
  10. Begic E, Begic Z. Accidental Heart Murmurs. Med Arch. 2017;71(4):284-287. doi:10.5455/medarh.2017.71.284-287
  11. McConnell ME, Adkins SB, Hannon DW. Heart murmurs in pediatric patients: When do you refer? Am Fam Physician. 1999;60(2):558-565.

 

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Modified Valsalva maneuver in the treatment of SVT – REVERT Trial

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Falling heels over head: you make my heart skip a beat

Resident Clinical Pearl (RCP) November 2019

 

Patricia Marks – PGY1 (FRCPC) Dalhousie University, Halifax, NS

Reviewed by Dr David Lewis

 

 

Introduction:

Supraventricular tachycardias (SVT) is a common presentation to the emergency room, and most patients will require treatment with adenosine or electrical cardioversion, as vagal maneuvers are less than 20% of the time in clinical practice. Adenosine and electrical cardioversion both require additional hospital resources, and adenosine is poorly tolerated by patients.

 

The REVERT trial published in 2015 in the Lancet by Appelboam et al. proposed a modified Valsalva maneuver in the treatment of SVT.  The study was a multicentre randomized control trial in England involving 433 patients with stable SVT. According to an intention to treat analysis, the authors found a 43% success rate of conversion to sinus rhythm with the modified Valsalva maneuver compared to 17% with standard Valsalva. No significant dangerous adverse effects occurred in this study.

 

Modified Valsalva: The How-To

  1. Patient identification:

    1. Is my patient eligible for Valsalva?
      • Stable SVT
      • Age > 18 years
      • Able to perform Valsalva
      • Able to lie flat and have legs lifted
    2. Contraindications:
      • Unstable or indication for immediate cardioversion
      • Atrial fibrillation, atrial flutter, sinus tachycardia
      • Recent MI
      • Aortic stenosis
      • Glaucoma
      • Retinopathy
      • Third trimester of pregnancy

  2. Materials

      • 10cc syringe
      • Manometer (optional)

  3. Performing the modified Valsalva maneuver

    1. Position the patient in a semi-recumbent position (45º)
    2. Instruct the patient to blow into the tip of a 10cc syringe for 15 seconds. The patient should be targeting a pressure reading on the manometer of 40mmHg, or blowing hard enough to move the plunger tip*
    3. Lower the patient flat and passively raise their legs to a 45º angle for 15 seconds
    4. Return the patient to a semi-recumbent position for an additional 45 seconds
    5. Assess the rhythm
    6. Repeat x1 if unsuccessful before moving on to adenosine or electrical cardioversion (provided the patient remains stable)

*The REVERT trial used a manometer to measure 40mmHg of pressure, however Smith and Boyle have demonstrated that 40mmHg of pressure is generated when a patient is instructed to blow into a 10cc syringe until the plunger moves

Image obtained from https://www.ecgmedicaltraining.com/wp-content/uploads/2016/06/REVERT-Trial-SVT.jpg on February 21, 2020.

 

Watch the REVERT authors perform the maneuver:

 

 

Benefits of this method:

  • Easy to instruct patients; can try at home
  • Higher success rate than standard Valsalva
  • Similar ED length of stay compared to standard Valsalva
  • Less patients require adenosine or cardioversion

Additional considerations

  • No formal studies exist for pediatric patients, however a recent case report by Rayburn and Wagers did demonstrate successful conversion to sinus rhythm with this maneuver

 

Bottom Line 

In adults with stable SVT, the modified Valsalva maneuver as published in the REVERT trial achieves a high rate of conversion to sinus rhythm with a NNT of 3.8 and without significant adverse effects. In patients without contraindications, the modified Valsalva maneuver is a low-cost and easy to teach strategy that should be trialled to convert patients in SVT prior to adenosine or electrical cardioversion.

 

 

References

  • Appelboam A, Reuben A, Mann C, Gagg J, Ewings P, Barton A, Lobban T, Dayer M, Vickery J, Benger J; REVERT trial collaborators. Postural modification to the standard Valsalva manoeuvre for emergency treatment of supraventricular tachycardias (REVERT): a randomised controlled trial. Lancet. 2015 Oct 31;386(10005):1747-53. doi: 10.1016/S0140-6736(15)61485-4.
  • Rayburn D, Wagers B. Modified Valsalva Maneuver for Pediatric Supraventricular Tachycardia. Pediatr Emerg Care. 2020 Jan;36(1):e8-e9. doi: 10.1097/PEC.0000000000002023
  • Smith G, Boyle MJ. The 10 mL syringe is useful in generating the recommended standard of 40 mmHg intrathoracic pressure for the Valsalva manoeuvre. Emerg Med  Australas. 2009 Dec;21(6):449-54. doi: 10.1111/j.1742-6723.2009.01228.x
  • Smith GD, Fry MM, Taylor D, Morgans A, Cantwell K. Effectiveness of the Valsalva Manoeuvre for reversion of supraventricular tachycardia. Cochrane Database of Systematic Reviews 2015, Issue 2. Art. No.: CD009502. DOI: 10.1002/14651858.CD009502.pub3
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PoCUS in Pericardial Effusion

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Medical Student Clinical Pearl – October 2019

 

Alex Pupek

Faculty of Medicine
Dalhousie University
CC4
Class of 2020

Reviewed and Edited by Dr. David Lewis

All case histories are illustrative and not based on any individual

Case

A 70F with a history of bladder CA, HTN and 4.9cm AAA presented to the Emergency Department (ED) and was Triaged as Level 3 with a chief complaint of generalized weakness. Initial assessment was significant for hypotension and low-grade fever with dysuria elicited on history; she was started on Ceftriaxone with a working diagnosis of urosepsis. Bloodwork and imaging studies were sent to rule out other potential sources of infection.

She had a mild leukocytosis of 12.4, pH of 7.23 and a lactate of 5.0. Point-of-care urinalysis was unremarkable. The chest x-ray revealed an enlarged cardiothoracic ratio of 0.62 compared to 0.46 ten months previously, concerning for a pericardial effusion.

Upon reassessment, the patient appeared unwell with slight mottling to the skin, cool extremities and tenuous blood pressure; point of care ultrasound revealed a large pericardial effusion.  Interventional cardiology was paged; the patient was moved to the trauma area and an emergent pericardiocentesis was performed: 360cc of bloody fluid was removed. The pericardial drain was left in situ.

Post-procedure bloodwork included a troponin of 216 and CK of 204. The patient was admitted to the Cardiac Care Unit and discharged within a week’s time.

 

Pericardial Effusions and The Role of Point-of-Care Ultrasound (POCUS)

The normal pericardial sac contains up to 50 mL of plasma ultrafiltrate [1]. Any disease affecting the pericardium can contribute to the accumulation of fluid beyond 50mL, termed a pericardial effusion. The most commonly identified causes of pericardial effusions include malignancy and infection (Table 1).

 

Table 1 – UpToDate, 2019 – Diagnosis and Treatment of Pericardial Effusions

 

Evaluation of the pericardium with point-of-care ultrasound includes one of four standard views: parasternal long axis, parasternal short axis, subxiphoid and apical (Figure 1). A pericardial effusion appears as an anechoic stripe or accumulation surrounding the heart. Larger effusions may completely surround the heart while smaller fluid collections form only a thin stripe layering out posteriorly with gravity. Seen most commonly post-cardiac surgery, pericardial effusions may be loculated and compress only a portion of the heart. [1,2] (Table 2)

Figure 1[1]

Table 2 [2]

 

Both the pericardial fat pad and pleural effusions can be mistaken for pericardial effusions. The parasternal long-axis view is most helpful to accurately define the effusion with the descending aorta, posterior to the mitral valve and left atrium, serving as a landmark: the posterior pericardial reflection is located anterior to this structure. Fluid anterior to the posterior pericardial wall is pericardial, whereas a pleural effusion will lie posterior. The pericardial fat pad is an isolated dark area with bright speckles, located anteriorly; unlike fluid, it is not gravity dependent. Rather than competing with the cardiac chambers for space within the pericardial sac, the fat pad moves synchronously with the myocardium throughout the cardiac cycle. [1,2] (Figure 2)

Figure 2[1]

A pericardial effusion discovered on POCUS in the ED may be mistaken for tamponade, leading to inappropriate and invasive management in the form of pericardiocentesis.[2]

Patient tolerance of pericardial effusions depends on the rate by which they accumulate. As little as 150-200 mL of rapidly accumulating effusion can cause tamponade whereas much larger amounts of slowly accumulating fluid can be well tolerated. Pericardial effusions formed gradually are accommodated by adaptations in pericardial compliance. A tamponade physiology is reached once the intrapericardial pressure overcomes the pericardial stretch limit.[2] (Figure 3)

Figure 3[2]

The core echocardiographic findings of pericardial tamponade consist of:

  • a pericardial effusion
  • diastolic right ventricular collapse (high specificity)
  • systolic right atrial collapse (earliest sign)
  • a plethoric inferior vena cava with minimal respiratory variation (high sensitivity)
  • exaggerated respiratory cycle changes in mitral and tricuspid valve in-flow velocities as a surrogate for pulsus paradoxus

In the unstable patient with clinical and echocardiographic findings of tamponade, an emergent pericardiocentesis is indicated.[2]

A retrospective cohort study of non-trauma emergency department patients with large pericardial effusions or tamponade, ultimately undergoing pericardiocentesis, found that effusions identified by POCUS in the ED rather than incidentally or by other means saw a decreased time to drainage procedures, (11.3 vs 70.2 hours, p=0.055).[3]

Point of care ultrasound is a valuable tool during the initial evaluation of the undifferentiated hypotensive emergency department patient but should be interpreted judiciously and within clinical context to avoid unnecessary emergency procedures.

Additional Images

From GrepMed



 




echocardiogram-pericardial-tamponade-alternans-effusion


 




References


    

  1. Goodman, A., Perera, P., Mailhot, T., & Mandavia, D. (2012). The role of bedside ultrasound in the diagnosis of pericardial effusion and cardiac tamponade. Journal of emergencies, trauma, and shock, 5(1), 72.
    2. 

  2. Alerhand, S., & Carter, J. M. (2019). What echocardiographic findings suggest a pericardial effusion is causing tamponade?. The American journal of emergency medicine, 37(2), 321-326.
    3. 

  3. Alpert, E. A., Amit, U., Guranda, L., Mahagna, R., Grossman, S. A., & Bentancur, A. (2017). Emergency department point-of-care ultrasonography improves time to pericardiocentesis for clinically significant effusions. Clinical and experimental emergency medicine, 4(3), 128.
    4. 



 

			

		

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EM Reflections – December 2019


				

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Thanks to Dr Joanna Middleton for leading the discussions this month


Edited by Dr David Lewis 




Discussion Topics










    

  1. 

    Cardiopulmonary Resuscitation In Patients With Mechanical Circulatory Support
    

      

    • Patient with mechanical circulatory support devices have unique clinical signs of cardiac arrest
      • 

    • Understanding the function of these devices ids critical to the management of these complex cases
      • 

    

    2. 

  2. 

    Aortic Dissection
    

      

    • Remains a commonly missed or delayed diagnosis
      • 

    • Once diagnosed, meeting the therapeutic goals requires a careful and considered approach
      • 

    

    3. 














Cardiopulmonary Resuscitation In Patients With Mechanical Circulatory Support


Case


A 70yr male presents with cardiac arrest. He has an LVAD. What are the implications for emergency management and cardiopulmonary resuscitation?












Introduction


Cardiac arrest in patients on mechanical support is a new phenomenon brought about by the increased use of this therapy in patients with end-stage heart failure.


It is important to understand the difference between blood flow and perfusion when assessing any patient with suspected cardiovascular hemodynamic instability, especially patients with an LVAD, in whom the peripheral arterial pulse is not a reliable indicator. Flow represents the forward movement of blood through the systemic circulation. It can be either adequate or inadequate to provide sufficient oxygen delivery to sustain tissue per- fusion. Assessment of adequate tissue perfusion is the most important factor in determining the need for circu- latory assistance such as chest compressions.










What is a Left Ventricular Assist Device?


With an LVAD, blood enters the device from the LV and is pumped to the central aortic circulation, “assisting” the heart.  The outflow cannula is typically anastomosed to the ascending aorta, just above the aortic valve. RA/RV still working




 




Blue Arrow – Important point as patients often present with iGel in place…


 


Unique Patient Properties


    

  • Pulses often absent

      

    • BP measured manually with a Doppler – MAP (50-90)
      • 

    

    • 

  • SpO2 may not be measurable
    • 

  • Anticoagulated
    • 

  • Need power!
    • 

  • Very reliant on RV function/preload
    • 

  • Leading cause of death – sepsis and stroke
    • 



Further Reading


Cardiopulmonary Resuscitation in Adults and Children With Mechanical Circulatory Support. A Scientific Statement From the American Heart Association





Aortic Dissection


Aortic dissection remains difficult to diagnosis with 1 in 6 being missed at the initial ED visit. Why? The diagnosis is rare with and incidence of only 2.9/100,000/year, and the presentation is often atypical mimicking other more common diagnoses such as ACS and stroke.


View The SJRHEM  – Aortic Dissection – Resident Clinical Pearl here:


Aortic Dissection




Diagnosis




The most common initial misdiagnoses are acute coronary syndrome, pulmonary embolism, and stroke. Patients with these suspected diagnoses should also be screened for high-risk features of acute aortic dissection. If none are present, they are unlikely to have an acute aortic dissection. If high-risk features are present, balance your clinical suspicion for an aortic dissection with the likelihood of an alternative diagnosis using an approach such as RAPID


How Do I rule Out Aortic Dissection – Just the Facts – CJEM


PoCUS


Early Screening for Aortic Dissection With Point‐of‐Care Ultrasound by Emergency Physicians


A total of 127 patients were enrolled: 72 in the US group and 55 in the control group. In the US group, compared with CTA, the sensitivity of EP POCUS was 86.4%, and the specificity was 100.0%.


 




 


Treatment Goals




From EMCases.com


 


Further Reading


Episode 92 – Aortic Dissection Live from The EM Cases Course




 

			

		

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Palpitations – A Paroxysmal Pearl


				

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Palpitations – A Paroxysmal Pearl


Medical Student Clinical Pearl




Scott Fenwick


Class of 2021




Faculty of Medicine


Dalhousie University






Reviewed and Edited by Dr. David Lewis




Case Presentation:


A 49-year-old female presented with palpitations for the past 2 hours. She had two similar episodes in the last 2 weeks, both of which resolved within 1-2 minutes. She had no other symptoms. She was otherwise healthy, with no past medical history. She was a non-smoke and non-drinker who leads an active lifestyle. She denied weight loss, diarrhea, and heat intolerance.


On physical exam, she was tachycardic at 130bpm with an irregularly irregular pulse. She did not display any tremor or diaphoresis. On auscultation, S1 and S2 were audible, with no murmurs or extra sounds. Respiratory and abdominal exams were unremarkable.




What to ask on History?


Common Symptoms: palpitations, tachycardia, fatigue, weakness, dizziness, light-headedness, reduced exercise capacity, mild dyspnea, and polyuria. It is essential to know when exactly the symptoms started. AF that presents before 48 hours can be safely rhythm controlled without anticoagulation.(1)


Severe/Secondary Symptoms: angina, dyspnea at rest, presyncope and, uncommonly, syncope. Embolic events and heart failure can be severe complications of AF.


Past Medical History: cardiovascular or cerebrovascular disease, diabetes, hypertension, COPD, obstructive sleep apnea, and hyperthyroidism.




What to look for On Examination?


ABCs and vitals: particularly pulse rate and rhythm.


General Assessment: look for signs of thyroid disease, PE, pulmonary disease, alcohol withdrawal, and signs of liver disease from excessive alcohol ingestion.


CVS: precordial scars from prior cardiac surgery, JVP, peripheral edema, and auscultation for murmurs or additional sounds that might suggest valvular AF. There is often an apical-radial pulse deficit where not every apical beat has an associated radial beat due to lack of left ventricular stroke volume.(2)




Case Continued – Testing: 


The patient was put on a cardiac monitor and an ECG was performed, demonstrating atrial fibrillation. There was also a right bundle branch block that was consistent with a previous ECG performed in 2017. Laboratory testing was unremarkable.


Depending on clinical suspicion, initial testing may include CBC, electrolytes, blood glucose, PT/INR, creatinine, BUN, TSH, cardiac enzymes, LFTs, and chest x-ray.2




See Basic ECG interpretation Pearl for a great guide to ECGs


Basic ECG Interpretation






 


Classifying Atrial Fibrillation: 


AF is classically described as an irregularly irregular heartbeat, as can be observed from the variable RR intervals in the ECG above. In AF, there are no distinct P-waves due to the uncoordinated atrial activity. Broadly, AF can be divided into valvular and non-valvular subtypes. Non-valvular AF can be classified into the following categories:(1)


    

  • Paroxysmal – AF terminates spontaneously or with intervention within 7 days of onset.
    • 

  • Persistent – AF fails to terminate within 7 days of onset; often a progressive disease.
    • 

  • Long-Standing Persistent – AF has persisted for greater than 12 months.
    • 

  • Permanent – Joint decision between patient and provider to no longer pursue rhythm control.
    • 



AF commonly progresses from paroxysmal to persistent states. The above classification only refers to primary atrial fibrillation, not AF that is secondary to cardiac surgery, pericarditis, myocardial infarction, valvulopathy, hyperthyroidism, pulmonary embolism, pulmonary disease, or other reversible causes.


For persistent and permanent AF, the CHADS2 score can be used to estimate a patient’s 1-year risk of ischemic stroke without anticoagulation (0 = low risk, 1-2 = moderate risk, 3+ = high risk).(1)




Calculate it here


 


CAEP and CCS now recommend using the CHAD-65 Score to determine anticoagulation requirement.




 




 


Treatment


DC and chemical (e.g. procainamide) cardioversion are two well-described methods of treating uncomplicated AF. The goal of treatment is to return patients to NSR. Some important points about the two methods include:


    

  • DC cardioversion can be administered at an initial energy dose of 100J and increased up to 360J as needed.(2)
    • 

  • Procainamide is often given in doses of 15-18mg/kg, or more simply, 1g over 60 minutes. Average time to cardioversion is about 1 hour.(1)
    • 

  • DC cardioversion requires procedural sedation; whereas, chemical cardioversion does not.
    • 

  • In a recent RCT, combination therapy achieved NSR in 99% of patients; Attempting DC cardioversion first decreased length of hospital stay by 1.2 hours.(3)
    • 

  • Both therapies are generally well-tolerated by patients.
    • 







Case Continued – Treatment: 


The patient was diagnosed with paroxysmal atrial fibrillation. The arrhythmia did not spontaneously resolve in the ED. DC and chemical cardioversion methods were considered and discussed with the patient. Direct Current (DC) cardioversion was performed under procedural sedation with propofol and fentanyl. Shocks of 100J and 200J were unsuccessful in converting the patient into normal sinus rhythm (NSR). A third shock at 300J was ultimately successful. The following ECG was obtained demonstrating NSR. As in the initial ECG, there is a RBBB present.


 




CHADS2 score was 0. Therefore anticoagulation or antithrombotic therapy not indicated.




 


Case Conclusion:


The patient was discharged home within 4 hours of arriving to hospital, anticoagulation was not prescribed. It is likely that she will experience AF again and require anticoagulation later in life.




 


References:


    

  1. January, C. T., Wann, L. S., Alpert, J. S., Calkins, H., Cigarroa, J. E., Cleveland, J. C., et al. (2014). 2014 AHA/ACC/HRS guideline for the management of patients with atrial fibrillation: Executive summary. Journal of the American College of Cardiology, 64(21), 2246. doi:10.1016/j.jacc.2014.03.021
    2. 

  2. Wakai, A., & Neill, J.O. (2003). Emergency management of atrial fibrillation. Postgrad Med J, 79(932), 313. doi:10.1136/pmj.79.932.313
    3. 

  3. Scheuermeyer, F. X., Andolfatto, G., Christenson, J., Villa-Roel, C., & Rowe, B. (2019). A multicenter randomized trial to evaluate a chemical-first or electrical-first cardioversion strategy for patients with uncomplicated acute atrial fibrillation. Academic Emergency Medicine, 26(9), 969-981. doi:10.1111/acem.13669
    4. 


			

		

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Color Flow Doppler to Assess Cardiac Valve Competence


				

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Color Flow Doppler to Assess Cardiac Valve Competence


Resident Clinical Pearl (RCP) April 2019




Dr. Scott Foley – CCFP-EM PGY3 Dalhousie University, Halifax NS


Reviewed by Dr. David Lewis


 




 


Background:


When colour Doppler is initiated, the machine uses the principals of the Doppler effect to determine the direction of movement of the tissues off which it is reflecting.


The Doppler effect is the change in frequency of a wave in relation to an observer who is moving relative to a wave source. It was named after the Austrian physicist Christian Doppler who first described the phenomenon in 1842. The classic example is the change in pitch of a siren heard from an ambulance as it moves towards and away from an observer.


These principles are applied to POCUS in the form of colour Doppler where direction of flow is reflected by the colour (Red = moving towards the probe, Blue = moving away from the probe), and the velocity of the flow is reflected by the intensity of the colour (brighter colour = higher velocity).

*Note: the colour does not represent venous versus arterial flow.


 




The use of colour Doppler ultrasound can be useful in the emergency department to determine vascular flow in peripheral vessels as well as through the heart. It is one way to determine cardiac valve competency by focusing on flow through each valve.




 


Obtaining Views:


To optimize valve assessment, proper views of each valve must be obtained. It is best to have the direction of the ultrasound waves be parallel to the direction of flow. External landmarks for the views used are seen below:




    

  • Mitral Valve and Tricuspid Valve: The best view for each of these is the apical 4 chamber view. If unable to obtain this view, the mitral valve can be seen in parasternal long axis as well.
    • 

  • Aortic Valve: The best view is the apical 5 chamber or apical 3 chamber but are challenging to obtain. Instead, the parasternal long axis is frequently used.
    • 

  • Pulmonic Valve: Although not commonly assessed, the parasternal short axis can be used.
    • 

  • Visit 5minutesono.com for video instruction on obtaining views
    • 







Parasternal long axis: MV, AV




Parasternal short axis: PV, TV




Apical 4 chamber: TV, MV




 


Assessing Valvular Competency:


How to examine valvular competency:


    

  1. Get view and locate valve in question
    2. 

  2. Visually examine valve: opening, closing, calcification
    3. 

  3. Use colour Doppler:

      

    1. Place colour box over valve (as targeted as possible (resize select box) to not include other valves)
      2. 

    2. Freeze image and scroll through images frame by frame
      3. 

    3. Examine for pathologic colour jets in systole and diastole
      4. 

    

    4. 

  4. Estimating severity:

      

    1. Grade 1 – jet noticeable just at valve
      2. 

    2. Grade 2 – jet extending out 1/3 of atrium/ventricle
      3. 

    3. Grade 3 – jet extending out 2/3 of atrium/ventricle
      4. 

    4. Grade 4 – jet filling entire atrium/ventricle
      5. 

    

    5. 



See video tutorial below for more






Mitral Regurgitation A4C




Tricuspid Regurgitation A4C




Aortic Stenosis PSLA




Bottom line:


Color flow Doppler on POCUS is a straightforward way to assess for valvular competency in the Emergency Department. A more detailed valvular assessment requires skill, knowledge and experience.


 




Useful Video Tutorials:


Mitral Regurgitation




 


Aortic Stenosis vs Sclerosis






Tricuspid Valve






References:


    

  1. https://www.radiologycafe.com/medical-students/radiology-basics/ultrasound-overview
    2. 

  2. By Patrick J. Lynch and C. Carl Jaffe – http://www.yale.edu/imaging/echo_atlas/views/index.html, CC BY 2.5, https://commons.wikimedia.org/w/index.php?curid=21448310
    3. 

  3. 5minutesono.com
    4. 

  4. ECCU ShoC 2018 powerpoint, Paul Atkinson, David Lewis
    5. 


			

		

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EM Reflections – January 2018


				

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Thanks to Dr Joanna Middleton for leading the discussion this month and providing these tips and references.


Edited by Dr David Lewis 


 


    

  1. 

    Occult Fractures of the Upper Limb
    

    2. 

  2. 

    Door to Needle/Balloon Times
    

    3. 

  3. 

    Mycotic Aneurysms
    

    4. 

  4. 

    CME Quiz
    

    5. 





Occult Fractures of the Upper Limb


In patients (particularly the elderly)who present with upper limb pain following a fall or other trauma, be careful not to miss an occult fracture. Localization may be impaired by dementia, acute confusion or other soft tissue injuries. Commonly missed fractures of the upper limb include:


    

  • Clavicle fracture
    • 

  • Supracondylar fracture
    • 

  • Radial Head/Neck fracture
    • 

  • Buckle fractures of the radius/ulna
    • 

  • Scaphoid fracture
    • 

  • Carpal dislocation
    • 

  • Any impacted fracture
    • 



Impacted fractures of the humeral neck may still allow some shoulder joint movement. Pain can be referred to the elbow (just as some hip injuries have pain referred to the knee).


When a fracture is strongly suspected ensure that the entire bone is included in the radiograph. If localization is impaired consider obtaining radiographs of the entire limb, starting with the most symptomatic area. Also follow the old mantra – “include the joint above and below” when ordering radiographs for suspected fracture.


Commonly missed fractures in the ED


Misses and Errors in Upper Limb Trauma Radiographs


 




Strategies to reduce door to ballon time


Delays in door to balloon time for the treatment of STEMI have been shown to increase mortality.


 


 




JACC 2006 Click on here for full text


 




BMJ 2009 – Click here for full text


 


This evidence has led to an international effort to establish strategies that can reduce door to balloon times


This rural program in the USA published their strategy for reducing door to ballon times below 90mins over a 4 year period. https://www.sciencedirect.com/science/article/pii/S0735109710043810. Their strategies included the following:


2005

• Community hospital physicians visited by interventional cardiologist with recommendations to:


∘ Perform ECG within 10 min of arrival for chest pain patients


∘ Communicate with PCI center physicians via dedicated STEMI hotline


∘ Treat and triage patients without consulting with primary physicians


∘ Give aspirin 325 mg chewed, metoprolol 5 mg IV × 3 when not contraindicated, heparin 70 U/kg bolus without infusion, sublingual nitroglycerin or optional topical nitropaste without routine intravenous infusion, and clopidogrel 600 mg PO


∘ Eliminate intravenous infusions of heparin and nitroglycerin.


2006

• Nurse coordinator hired to oversee program and communicate with emergency department personnel at all referring hospitals.


• Recommendations for medications listed above were formally endorsed for all STEMI patients.


• Formal next-day feedback provided to referring hospitals, including diagnostic and treatment intervals and patient outcomes.


• Quarterly “report cards” issued to each referring hospital emergency department.


2007

• PCI hospital emergency physicians directly activated the interventional team (instead of discussing it first with the interventional cardiologist on call).


• A group page was implemented for simultaneous notification of all members of the interventional team and catheterization laboratory staff of an incoming STEMI patient.

ECG = electrocardiogram; IV = intravenous; PCI = percutaneous coronary intervention; PO = by mouth; STEMI = ST-segment elevation myocardial infarction.


 


However recent commentaries have highlighted the pitfall of this metric


 


The Challenges and Pitfalls of Door-to-Balloon Time as a Performance Metric


https://www.medscape.com/viewarticle/537538


 


and further evidence has shown no improvement in mortality despite reducing door to balloon times. However, it should be noted that these centres were already achieving < 90 min.




http://www.nejm.org/doi/full/10.1056/NEJMoa1208200


This may be a result of multiple confounding factors:


total ischemic time may be a more important clinical variable than door-to-balloon time


it has been suggested that the association between door-to-balloon time and mortality may be affected by an “immigration bias” – healthier patients are likely to have shorter door-to-balloon times than are sicker patients with more complex conditions, for whom treatment may be delayed because of the time needed for medical stabilization


 


Whilst strategies to ever reduce door to balloon times may not be the correct focus to reduce overall mortality, it is clear that the presence of significant delays (>90mins) is associated with increased mortality.


 




Mycotic Aneurysms


Any kind of infected aneurysm, regardless of its pathogenesis. Such aneurysms may result from bacteremia and embolization of infectious material, which cause superinfection of a diseased and roughened atherosclerotic surface.


 


Aneurysmal degeneration of the arterial wall as a result of infection that may be due to bacteremia or septic embolization 


    

  • Symptoms:  pulsatile mass, bruit, fever
    • 

  • Risk Factors:  arterial injury, infection, atherosclerosis, IV drug use
    • 

  • #1 cause = staph, #2 = salmonella
    • 




Download (PDF, 1.14MB)


 




 


CME QUIZ

        

            
EM Reflections - Jan 18 - CME Quiz
        
                
                
                

            

                
EM Reflections – Jan 18 – CME Quiz

            


            
            

                
            

        

                
                
                
                
                
                
                
                
                

                
        
			

		

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ED Rounds – October 2015


				

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This month ED Rounds were presented by Dr Mike Howlett  , Dr James French and Dr Wendy Alexander (Pediatrician SJRH).


 


Congestive Heart Failure – Dr Mike Howlett


Dr Howlett presented 4 cases that highlighted the differences in pathophysiology and approaches to treatment for CHF in the ED.


The definition of Congestive Heart Failure (ESC 2012 Guidelines)


a syndrome in which patients have typical symptoms (e.g. breathlessness, ankle swelling, and fatigue) and signs (e.g. elevated jugular venous pressure, pulmonary crackles, and displaced apex beat) resulting from an abnormality of cardiac structure or function


Diagnosis of CHF


The diagnosis of heart failure with reduced ejection fraction (Systolic) and Heart Failure with preserved ejection fraction (Diastolic) is summarised in the box below.


Diagnosis HF


The mortality of Diastolic and Systolic HF are similar


CHF_Oct_2015_pptx


Dr Howlett’s full presentation can be downloaded / viewed below:



Download (PDF, 7.3MB)


 


How to be Awesome at Simulation – Dr James French


Dr French presented an interactive session that highlighted the important steps to designing, running and debriefing a simulation.


See our Simulation Program page for more details


Presentation to be uploaded here soon…


 


Pediatric Asthma – Dr Wendy Alexander


Dr Alexander presented pediatric pearls accumulated over her 25 years of practice.


See the SJRHEM Pediatric Asthma Guidelines


 


 


 


 

			

		

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