Master the board step 3

Cardiology
Splitting of S2
Wide, P2 Delayed Paradoxical, A2 Delayed Fixed
• Right bundle branch block
• Pulmonic stenosis
• Right ventricular hypertrophy
• Pulmonary hypertension
• Left bundle branch block
• Aortic stenosis
• Left ventricular hypertrophy
• Hypertension
ASD
Cardiomyopathy
Dilated Cardiomyopathy
Dilated cardiomyopathy presents and is managed in the same way as the case
of CHF described above.
Diagnostic Testing
Echocardiography is the best initial test to determine the ejection fraction and
look for wall motion activity. MUGA or nuclear ventriculography is the most
accurate method of determining ejection fraction.
Treatment
Besides ischemia, the most common causes of dilated cardiomyopathy are
alcohol, adriamycin, radiation, and Chagas’ disease. The treatment for
all forms of dilated cardiomyopathy, no matter their cause, is with ACE
inhibitors, ARBs, beta blockers, and spironolactone. Spironolactone and
eplerenone are mineralocorticoid or aldosterone antagonists. They are used
to decrease the work of the heart; they are not given for their diuretic effect.
Spironolactone is anti-androgenic and inhibits testosterone. Eplerenone does
not inhibit androgens. Digoxin decreases symptoms but does not prolong
survival.
Hypertrophic Cardiomyopathy
This condition presents with shortness of breath on exertion and an S4 gallop
on examination.
Diagnostic Testing
Echocardiography shows a normal ejection fraction.
Treatment
The mainstay of therapy is with beta blockers and diuretics. ACE inhibitors
can be used, but their benefit is not as clear. Digoxin and spironolactone do not
benefit hypertrophic cardiomyopathy.
S4 gallop is a sign of left
ventricular hypertrophy
and decreased compliance
or stiffness of the ventricle.
S4 gallop does not
automatically indicate
the need for additional
therapy.
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