Biatrial appendage hypertrophy but not ventricular hypertrophy: a unique feature of canine pacing-induced heart failure.

Journal Article

BACKGROUND: The canine model of pacing-induced heart failure is characterized by an absence of ventricular hypertrophy despite severe hemodynamic stress and neurohormonal activation. Given the mode of ventricular pacing, hypertrophy might occur in the atrial appendage. METHODS AND RESULTS: Seventeen dogs underwent continuous right ventricular pacing for 3 weeks to severe heart failure. Twelve normal dogs served as control subjects. Pacing produced marked increases in both pulmonary capillary wedge pressure (7.6 +/- 1.8 mmHg at baseline to 32.6 +/- 7.5 mmHg at 3 weeks, P < .001) and right atrial pressure (6.5 +/- 1.8 to 15.1 +/- 2.4 mmHg, P < .001), marked increases in normalized left ventricular volume (3.0 +/- 0.5 to 4.6 +/- 0.5 mL/kg, P < .001) and left atrial volume (1.0 +/- 0.2 to 2.6 +/- 0.5 mL/kg, P < .001), but no change in left ventricular mass (2.3 +/- 0.4 to 2.6 +/- 0.5 g/kg, differences not significant), indicating no ventricular hypertrophy. Compared to the control dogs, total heart weight in the test animals was similar, but both the left appendage (0.18 +/- 0.04 vs 0.10 +/- 0.03 g/kg, P < .001) and right atrial appendage (0.15 +/- 0.03 vs 0.12 +/- 0.02 g/kg, P = .004) were much heavier than those of the control dogs. CONCLUSIONS: Rapid right ventricular pacing in the dog induces severe heart failure associated with a dichotomous response in the atrial appendage versus the ventricle. Aside from being a useful heart failure model that simulates the human condition, this unique feature may have physiologic implications in terms of atrial mechanical and endocrine functions and have applications for future studies into the mechanisms of cardiac remodeling and hypertrophy.

Full Text

Duke Authors

Cited Authors

  • Moe, GW; Grima, EA; Howard, RJ; Armstrong, PW

Published Date

  • June 1996

Published In

Volume / Issue

  • 2 / 2

Start / End Page

  • 127 - 132

PubMed ID

  • 8798114

Electronic International Standard Serial Number (EISSN)

  • 1532-8414

International Standard Serial Number (ISSN)

  • 1071-9164

Digital Object Identifier (DOI)

  • 10.1016/s1071-9164(96)80031-5

Language

  • eng