A wave

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Overview

The a wave is an upward deflection in the right atrial pressure that occurs during right atrial contraction.

See the main page on JVP waveforms for more details.

a = atrial contraction, occurs just before 1st heart sound and carotid pulse x = atrial relaxation c = bulging of tricuspid valve during isovolumetric contraction; x 1 = occurs during ventricular contraction pulling down the tricuspid valve “descent of the base”; v = occurs during venous filling of the atrium with a closed tricuspid valve\; y = opening of tricuspid valve and right atrium emptying

Abnormalities in the JVP Waveforms

Absence of a wave	Atrial fibrillation
Flutter of a wave	Atrial flutter
Prominent a waves	First-degree atrioventricular block
Large a waves	Tricuspid stenosis, Right atrial myxoma, Pulmonary hypertension, Pulmonic stenosis
Absent x descent	Tricuspid regurgitation
Prominent x descent	Conditions associated with large a waves
Slow y descent	Tricuspid stenosis, Right atrial myxoma
Rapid y descent	Constrictive pericarditis, severe Right heart failure, Tricuspid regurgitation, Atrial septal defect
Absent y descent	Cardiac tamponade