A 62-year-old man with a history of hypertension comes to establish care. He recently moved to the area and states that his prior physician was treating him for high blood pressure. The patient has no current symptoms and feels healthy. He describes his lifestyle as mostly sedentary but reports no limitations with walking at a fast pace. The patient takes chlorthalidone and losartan for hypertension. Five years ago, he was diagnosed with hyperlipidemia and was offered medication but refused. The patient has never smoked and does not drink alcohol. His father had open-heart surgery at age 70, but the patient cannot provide further details. He has 2 siblings, both of whom are healthy. Blood pressure is 162/80 mm Hg and heart rate is 72/min. An ejection-type systolic murmur is heard at the right upper-sternal border. Which of the following findings is most consistent with severe aortic stenosis in this patient?
A detailed physical examination can provide clues to the presence and severity of valvular aortic stenosis (AS). The following examination findings are consistent with severe AS:
In normal physiology, inspiration pulls blood into the right side of the heart and results in delayed closure of the pulmonic valve and earlier closure of the aortic valve; a noticeable split of the aortic (A2) and pulmonic (P2) components of S2 can be appreciated. However, in severe AS, closure of the aortic valve is delayed, which results in nearly simultaneous closure of the aortic and pulmonic valves during inspiration, and is appreciated on examination as a single S2. The splitting can sometimes be paradoxical, where delayed closure of the aortic valve causes A2 to occur noticeably after P2.
(Choice A) Early peaking of an AS murmur is suggestive of mild to moderate AS because relatively low left ventricular pressure (attained early in ventricular systole) is needed to overcome the valvular stenosis.
(Choice B) A severely stenotic aortic valve creates a low-intensity sound during closure. High intensity of S2 is more consistent with mild to moderate AS.
(Choice C) A third heart sound is typically caused by blood filling a dilated ventricular cavity in a patient with heart failure. Severe AS can lead to heart failure, but this patient's absence of signs of heart failure (eg, dyspnea, peripheral edema) makes the presence of a third heart sound unlikely. In a patient with severe AS and no evidence of heart failure, the presence of a fourth heart sound (due to concentric left ventricular hypertrophy and decreased wall compliance) is more likely.
(Choice E) Because pulse pressure (the difference between systolic and diastolic pressure) is directly related to stroke volume, patients with severe AS are unable to create wide pulse pressures. Wide pulse pressures are often seen in patients with aortic regurgitation.
Educational objective:
The presence of a low-intensity, single second heart sound during inspiration is consistent with severe aortic stenosis. Other findings suggestive of severe AS include delayed and diminished carotid pulse and loud and late-peaking systolic murmur.