Effect of coronary occlusion during percutaneous transluminal angioplasty in humans on left ventricular chamber stiffness and regional diastolic pressure-radius relations

Abstract

The effect of repeated (3 to 10 second) and transient (15 to 75 second) abrupt coronary occlusion on the global and regional chamber stiffness was studied in nine patients undergoing angioplasty of a single proximal left anterior descending coronary artery stenosis. The left ventricular high fidelity pressure and volume relation was obtained before and after the procedure as well as during coronary occlusion, after 20 seconds (n = 9) and after 50 seconds (n = 5). During ischemia, there was an upward shift of the pressure-volume relation. The nonlinear simple elastic constant of chamber stiffness increased from 0.0273 +/- 0.017 before angioplasty (mean +/- SD) to 0.0621 +/- 0.026 after 20 seconds of occlusion (p less than 0.05) and 0.0605 +/- 0.015 after 50 seconds of occlusion (p less than 0.01). In five patients, the postangioplasty value remained higher than the control value, but at the group level the mean value (0.0529 +/- 0.037) was not statistically different. The regional stiffness was determined from the changes in the length of six segmental radii during diastole, from the lowest diastolic to the end-diastolic pressure. The regional constant of elastic stiffness was unaffected in the nonischemic zone. In the adjacent and ischemic zones, the regional stiffness was increased during occlusion (p less than 0.05). These regional abnormalities in diastolic function persisted at the time of postangioplasty measurements, 12 minutes after the end of the procedure. This suggests that recovery of normal diastolic function after repeated ischemic injuries is delayed after restoration of normal blood flow and systolic function.

Effects of graded reductions in coronary perfusion pressure on the diastolic pressure-segment length relation and the rate of isovolumic relaxation in the resting conscious dog.

“…Previous investigations1 12 have reported that the rate of isovolumic relaxation, reflected by peak negative dP/dt or T, decreases during ischemia, but these investigations have not provided any information on the quantitative aspects of this association. Figure 7 (upper panel) shows that there are two phases to this relation and that the sensitivity of the rate of isovolumic relaxation to reductions in coronary perfusion pressure depends on the pressure achieved.…”

Clinical Phenotypes in Heart Failure With Preserved Ejection Fraction

“…Though abnormal relaxation is the first mechanical manifestation of myocardial ischemia,194, 195, 196 acute coronary artery syndromes seldom precipitate HFpEF decompensation or present as HFpEF 100, 197. The prevalence of CAD ranges from 35% to 53% in large HFpEF registries 34, 35, 198.…”

Medical and Cellular Implications of Stunning, Hibernation, and Preconditioning

“…Brief coronary occlusions (Ͻ60 seconds) induced at the time of angioplasty have been associated with persistent abnormalities in ventricular compliance. 93 Sheiban et al 94 induced longer periods of coronary artery occlusion (5 to 7 minutes) during angioplasty and observed that recovery of regional wall motion required 24 to 36 hours. Recovery in function was improved with calcium channel blockade.…”