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A 34-year-old Russian immigrant comes to the office with a 2-month history of exertional dyspnea and progressive lower extremity swelling. He also reports abdominal distension and decreased appetite. The patient has gained 4.5 kg (9.9 lb) over the last 2 months. Medical history is significant for hypertension and recurrent lung infections requiring prolonged antibiotic therapy. The patient has no history of coronary artery disease. He has smoked a pack of cigarettes daily for the past 15 years. The patient undergoes noninvasive cardiac testing, followed by cardiac catheterization. A jugular venous pressure tracing is shown in the image below:
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Item 1 of 2
The waveform indicated by the arrow most likely corresponds to which of the following?
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The jugular venous pulsation (JVP) waveform is representative of pressure changes in the right atrium throughout the cardiac cycle; the normal waveform consists of 3 peaks (A, C, and V) and 2 descents (x and y).
The A wave is caused by atrial contraction at the end of right ventricular diastole, which occurs just before tricuspid valve closure (indicated by S1) (Choice D). The C wave then occurs due to right ventricular contraction (Choice C) against a closed tricuspid valve, which bulges into the right atrium. There is an ensuing decrease in pressure (x descent) as the emptied right atrium relaxes, followed by an uptrend as the right atrium refills with blood from the vena cava. This uptrend culminates in the V wave at the peak of right atrial filling. The pulmonic valve closes (indicated by S2) and the tricuspid valve opens (Choice E) to mark the beginning of passive right atrial emptying into the right ventricle (y descent).
The A wave is absent in patients with atrial fibrillation because no organized atrial contraction takes place.
(Choice B) Pressure changes in the systemic arterial circulation (eg, carotid pulse upstroke) are not represented on the JVP waveform. However, because both the right ventricle and the left ventricle contract simultaneously, the carotid pulse upstroke should occur right around the time of the C wave on the JVP waveform.
Educational objective:
On the jugular venous pulsation waveform, the A wave is generated by atrial contraction at the end of right ventricular diastole just before tricuspid valve closure.