An analysis of regional left ventricular function utilizing pressure-length relationship in XXXX with @entity453 .

@entity1 @entity64 @entity63 @entity591 @entity158 @entity741 @entity7099 @entity453
Mechanisms related to increased left ventricular filling pressure associated with @entity741 were studied in 13 @entity1 with @entity453 . Single-plane left ventriculograms were obtained using a high fidelity micromanometer-tipped catheter in the control and post-pacing periods. All @entity1 developed typical @entity158 during pacing @entity591 . Seven @entity1 (group I) demonstrated no significant changes in ejection fraction (EF) and peak systolic pressure-end-systolic volume ratio (P/Ves) after rapid pacing. End-diastolic pressure (EDP), however, increased significantly from 14.9 +/- 4.9 to 24.4 +/- 8.5 mmHg (p less than 0.01). Six @entity1 (group II) exhibited significant decreases in EF and P/Ves. Here again, EDP increased significantly from 14.0 +/- 7.6 to 28.0 +/- 7.7 mmHg (p less than 0.01). The regional myocardial function was expressed by a radial coordinate system with its origin at the center of gravity of the end-diastolic contour. In the normal segment, the end-diastolic length (EDL) was augmented by 13.6%, associated with a 22.4% increase in @entity64 excursion with pacing stress. In the @entity63 segment, EDL remained unchanged, but @entity64 excursion was significantly reduced. The diastolic pressure-volume curve shifted directly upward or more to the right, while the diastolic pressure-length curve moved up on the single curve in the normal segment and shifted directly upward in the @entity63 segment, so that pressure was higher at any given segment length in the @entity63 segment, indicating regional alteration of the diastolic properties. Thus, an @entity63 response to pacing @entity591 involves both @entity7099 , but the latter is more sensitive.(ABSTRACT TRUNCATED AT 250 WORDS)
