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).
Patient 1:
This patient was admitted to the hospital with recurrent infective endocarditis involving a prosthetic tricuspid valve. On examination, there was a late crescendo diastolic murmur that augmented with inspiration heard over the left lower sternal border, consistent with tricuspid stenosis. These videos demonstrate a jugular venous waveform with giant a waves. When the right atrium contracts against a stenotic tricuspid valve at the end of diastole, it results in an increase in pressure in the right atrium.
Video Courtesy of BMJ case reports: “Giant a waves”
*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
Annotated
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
Annotated
Patient 3:
This patient has giant a waves from severe pulmonary hypertension.
Giant a Wave
Patient 4:
This is a middle-age man with cirrhosis who was admitted to the hospital with hepatic encephalopathy. Qualitative assessment of the jugular venous waveform revealed giant a waves, the cause of which was not determined this hospitalization. Recent echocardiogram did not show any evidence of tricuspid stenosis or pulmonary hypertension.
Patient 5:
This patient has giant a wave.