No abstract

The exercise-induced increase in P-wave duration reported previously has not been studied on a minute-by-minute basis. We measured the P duration in 47 normal subjects and 43 coronary artery disease (CAD) patients each minute during an exercise test. We found that prolongation of the P wave in those with CAD occurs relatively early and the difference between normal subjects and CAD patients is greater near maximum exercise. The data suggest that an increase in P-wave duration may reflect an increase in the left-ventricular end-diastolic pressure and may occur earlier that ST-segment depression.

Dense annular calcification to the valve attachment is particularly hazardous during mitral valve replacement because of the difficulty of placing sutures and the risk of atrioventricular rupture. We report 11 patients who underwent decalcification of the mitral anulus with the Cavitron Ultrasound Surgical Aspirator (CUSA) during mitral valve replacement. This resulted in a greatly simplified suture placement and prosthetic valve seating as well as enlargement of the annular orifice. Four other patients underwent CUSA debridement of the anterior leaflet of the mitral valve during concomitant aortic valve replacement and CUSA debridement of the aortic anulus. There were no operative deaths or major complications. Ultrasonic debridement is a useful adjunct in the surgical management of the heavily calcified mitral valve.