Giant a Wave

The a wave of the jugular venous waveform occurs as a result of right atrial contraction. When there is resistance to right ventricular filling, right atrial contraction generates increased pressure, resulting in giant a waves. These waves occur with every beat, unlike cannon a waves, which usually occur intermittently. Causes of giant a waves include tricuspid stenosis and increased right ventricular end-diastolic pressure from any cause (e.g., pulmonary hypertension).

Card Tutorial

Patient 2

This patient was admitted to the hospital with decompensated right heart failure from severe pulmonary hypertension caused by methamphetamine use. On examination, there was a a right ventricular heave as well as a loud pulmonary component of the second heart sound, consistent with pulmonary hypertension. These videos demonstrate a jugular venous waveform with giant a waves. Pulmonary hypertension creates resistance to right atrial filling as a result of elevated right ventricular end-diastolic pressure.

*It may be easier to appreciate this video by slowing it down to half speed (click the gear icon in the bottom right corner of the video)

Giant a Wave

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