cannon a wave

An abnormal jugular venous pressure curve with an accentuated ‘a’ wave of sufficient intensity to cause the earlobes to ‘flap’, due to decreased right ventricular compliance, tricuspid stenosis or an arrhythmia in which the atrium contracts against a closed or stenosed tricuspid valve; a less ‘explosive’ but still prominent ‘a’ wave may by associated with pulmonary hypertension. Cannon ‘a’ waves may be regular—as are AV junctional rhythms, in which an ‘a’ wave occurs every 2nd beat in a 2:1 block—or irregular, which is more common and may occur in complete heart blocks without atrial fibrillation, ventricular tachycardia, or AV dissociation
Segen's Medical Dictionary. © 2012 Farlex, Inc. All rights reserved.

cannon 'a' wave

Cardiology An abnormal jugular venous pressure curve with an accentuated 'a' wave of sufficient intensity to cause the earlobes to 'flap', due to ↓ right ventricular compliance, tricuspid stenosis or an arrhythmia in which the atrium contracts against a closed or stenosed tricuspid valve; a less 'explosive' but still prominent 'a' wave may by associated with pulmonary HTN; CAWs may be regular, as are AV junctional rhythms, where a CAW occurs every 2nd beat in a 2:1 block, or irregular, which are more common and may occur in complete heart blocks without A Fib, V tach, AV dissociation
McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.