SYSTOLIC TIME INTERVALS IN ATRIAL FIBRILLATION 629 Systolic Time Intervals in Atrial Fibrillation
نویسندگان
چکیده
Forty patients with atrial fibrillation and 20 patients with congestive heart failure and sinus rhythm were studied. Patients were divided into two groups. Group A consisted of 20 patients with atrial fibrillation in whom systolic time intervals were measured. Twenty to 50 beats were analyzed. Five of the patients had high-fidelity measurements of left ventricular pressure simultaneous with determination of systolic time intervals. Analysis of the systolic time intervals for the entire group showed that the preejection period lengthened at faster heart rates and that the left ventricular ejection time was relatively constant at slower heart rates. This resulted in a progressive increase in the ratio of preejection period over left ventricular ejection time (PEP/LVET) as the heart rate increased. The rate of increase in PEP/LVET was mini-
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