Prolonged local ischemia and mechanical alterations in left ventricular wall thickening following brief periods of coronary occlusion in conscious dogs

G. R. Heyndrickx, P. Nellens, H. Baig, S. F. Vatner

Research output: Contribution to journalArticlepeer-review

Abstract

Brief coronary (C) occlusions (O) to (<15 min) are thought not to cause myocardial necrosis, but result in prolonged depression of regional mechanical function. This could be due to prolonged local ischemia. To analyze this problem, 8 conscious dogs were studied 2-4 wk after implantation of Doppler flow (F) probes and occluders on left (L) circumflex C artery, L atrial catheters, L ventricular pressure gauges and ultrasonic dimension transducers to measure segment length and wall thickness. During CO, ischemic zone (IZ) F fell by 70 ± 2% from .90 ± .05 ml/min/g, while IZ function showed paradoxical motion and absence of systolic wall thickening. Reperfusion was characterized by reactive hyperemia, subsiding by 12 min, and a parallel increase in end-diastolic wall thickness, subsiding by 15 min. At 30 min after reperfusion systolic wall thickening was depressed by .89 ± .25 mm from a control of 11.39 ± .78 mm. At this time IZ F was reduced by 19 ± 3%, ENDO F was depressed more than EPI F resulting in an abnormal ENDO/EPI ratio of 1.07 ± .06 (control = 1.24 ± .06). Systolic wall thickenig remained depressed for over 3 hr. Thus, following release of transient CO, abnormal regional perfusion in particular in the endocardium, may explain prolonged depression of reginal function, as refleted by impaired systolic wall thickening.

Original languageEnglish (US)
Pages (from-to)No. 1472
JournalFederation Proceedings
Volume36
Issue number3
StatePublished - 1977
Externally publishedYes

ASJC Scopus subject areas

  • Medicine(all)

Fingerprint

Dive into the research topics of 'Prolonged local ischemia and mechanical alterations in left ventricular wall thickening following brief periods of coronary occlusion in conscious dogs'. Together they form a unique fingerprint.

Cite this