A 46-year-old man comes to the office for an annual examination. He has an uncomfortable heartbeat sensation at night that he tries to decrease by sleeping on his right side. The patient has had mild shortness of breath with exertion over the last 6 months, but he has no chest pain. He was told during a wellness check approximately 2 years ago that he had a heart murmur. The patient has no other medical problems. Physical examination reveals bounding femoral pulses and carotid pulsations that are accompanied by head bobbing. Which of the following is the most likely diagnosis?
This presentation is most suggestive of aortic regurgitation. The inability of aortic valve leaflets to effectively close during diastole leads to regurgitation of blood back into the left ventricular (LV) cavity with an increase in LV end-diastolic volume and wall stress. The resultant chamber enlargement and eccentric hypertrophy increase total stroke volume, which is often felt as a sense of pounding or an uncomfortable feeling of heartbeat (especially when lying on the left side).
Physical examination reveals an early "blowing" diastolic decrescendo murmur best heard at the left sternal border in the third or fourth intercostal space. The precordial impulse is hyperdynamic and displaced laterally and downward. Bounding femoral and carotid pulses, marked by abrupt distension and quick collapse ("water-hammer" pulses), are the result of the wide pulse pressure. Some patients exhibit head bobbing with carotid pulsations (de Musset sign) due to transfer of momentum from the large LV stroke volume to the head and neck. Significant systolic pulsations may also be noticed in other organs (eg, liver, spleen, retina) and the fingertips.
(Choice B) Patients with severe aortic stenosis have a characteristic arterial pulse – small pulse amplitude (pulsus parvus) with a delayed peak and slower upstroke of the arterial pulse (pulsus tardus) due to diminished stroke volume and prolonged ejection time.
(Choice C) The presence of atrial septal defect leads to left-to-right intracardiac shunting, which can cause a hyperdynamic right ventricular impulse. It does not cause any significant change in arterial pulse character.
(Choice D) Coarctation of the aorta causes systolic hypertension in the upper extremities along with characteristic diminished and/or delayed femoral pulses (brachial-femoral delay).
(Choice E) Arterial pulse, pulse pressure, and forward stroke volume remain normal in patients with chronic (compensated) mitral regurgitation.
(Choice F) Arterial pulses are reduced in volume and amplitude in patients with mitral stenosis due to decreased LV end-diastolic volume and stroke volume.
(Choices G and H) Tricuspid regurgitation and/or pulmonary stenosis are right-sided valvular lesions and do not cause any specific arterial pulse pattern on physical examination.
Educational objective:
Aortic regurgitation causes an increase in total stroke volume with abrupt distension and rapid falloff of peripheral arterial pulses, resulting in a wide pulse pressure. This leads to bounding peripheral pulses and head bobbing with each heartbeat.