Differential Dx - Neck Veins Exam - Physical Diagnosis Skills - University of Washington School of Medicine

Waveform	Cardiac Condition
Absent a wave	Atrial fibrillation, sinus tachycardia
Flutter waves	Atrial flutter
Prominent a waves	First-degree atrioventricular block
Large a waves	Tricuspid stenosis, right atrial myxoma, pulmonary hypertension, pulmonic stenosis
Cannon a waves	Atrioventricular dissociation, ventricular tachycardia
Absent x descent	Tricuspid regurgitation
Prominent x descent	Conditions causing enlarged a waves
Large cv waves	Tricuspid regurgitation, constrictive percarditis
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

Discussion

Abnormal A Wave

Abnormally Prominent A Wave

This is usually due to decreased compliance of the right ventricle due to right ventricular hypertrophy. Thus it may indicate right ventricular outflow obstruction, pulmonary vascular obstruction, chronic pulmonary disease, elevated pulmonary wedge pressure form any cause or congestive, hypertrophic or restrictive cardiomyopathy.

Cannon a waves occur during systole.

Giant a waves occur on every beat while cannon a waves result from arrhythmias; and, therefore, are intermittent and on a minority of beat. Causes of cannon a wave are av dissociation from heart block or pacers and premature ventricular contraction.

Absent a wave: In atrial fibrillation, the a wave is absent.

Abnormal V Wave

The v wave is increased when there is increased atrial filling during systole. The most common cause is tricuspid regurgitation. (often called a cv wave or s wave as it begins during the c wave) It is specific but not sensitive for tricuspid regurgitation as a large and compliant atrium can mitigate the effect of the regurgitation on the jugular vein wave forms.

Atrial septal defect also can result in a larger v wave that equals the a wave in its size.

Abnormal X and Y Descents

An absent x descent can result from tricuspid regurgitation.

In constrictive pericarditis and restrictive cardiomyopathy x and y descents can be extremely prominent and rapid and the corresponding a and v wave ascents are notably abrupt. A prominent y descent has been found to occur in about one-third of the patients with constrictive pericarditis, and two thirds of patients with right ventricular infarction. The presence of a rapid y descent excludes the diagnosis of pericardial tamponade.