Left ventricular adaptation to aortic regurgitation in conscious dogs.

Published

Journal Article

OBJECTIVE: Cardiac failure as a result of valvular heart disease remains a major clinical problem that frequently leads to ventricular dysfunction, myocardial failure, and even death. The development of irreversible myocardial damage may be especially insidious in volume overload as a result of aortic or mitral regurgitation. METHODS AND RESULTS: Left ventricular wall volume, ventricular function, and myocardial performance were assessed in 10 chronically instrumented conscious dogs before and after creation of aortic regurgitation. Left ventricular wall volume was measured by serial echocardiography. Left ventricular function was assessed by total cardiac output, stroke work, the slope of the Frank-Starling relationship, and the slope of the end-systolic pressure-volume relationship. Myocardial performance was assessed by the slope of the myocardial power output versus end-diastolic strain relationship. End-diastolic wall stress and volume both increased acutely and remained elevated after creation of aortic regurgitation. Peak systolic wall stress increased initially (1 to 3 weeks) from 336 +/- 30 to 369 +/- 55 mm Hg but returned to control values as left ventricular wall volume increased from 78 +/- 13 to 88 +/- 16 ml after development of compensatory hypertrophy. Left ventricular systolic function remained constant or increased and was maintained initially by increased myocardial performance, which returned to baseline levels after the development of compensatory hypertrophy. CONCLUSIONS: Myocardial performance and ventricular function vary independently in aortic regurgitation. Measures of myocardial performance such as the myocardial power output versus end-diastolic strain relationship may be useful in clinical assessment of aortic regurgitation.

Full Text

Duke Authors

Cited Authors

  • Gaynor, JW; Feneley, MP; Gall, SA; Savitt, MA; Silvestry, SC; Davis, JW; Rankin, JS; Glower, DD

Published Date

  • January 1997

Published In

Volume / Issue

  • 113 / 1

Start / End Page

  • 149 - 158

PubMed ID

  • 9011684

Pubmed Central ID

  • 9011684

Electronic International Standard Serial Number (EISSN)

  • 1097-685X

International Standard Serial Number (ISSN)

  • 0022-5223

Digital Object Identifier (DOI)

  • 10.1016/s0022-5223(97)70410-0

Language

  • eng