Faculty Collaboration Database

Influence of isoflurane on left atrial function in dogs with pacing-induced cardiomyopathy: evaluation with pressure-volume relationships. J Cardiothorac Vasc Anesth 2003 Dec;17(6):709-14

Date

12/23/2003

Pubmed ID

14689410

DOI

10.1053/j.jvca.2003.09.006

Scopus ID

2-s2.0-0347360349 (requires institutional sign-in at Scopus site)   5 Citations

Abstract

OBJECTIVE: The actions of volatile anesthetics on left ventricular (LV) function in normal and failing hearts have been previously evaluated, but the effects of these agents on left atrial (LA) function in the presence of LV dysfunction are unknown. The hypothesis was tested that isoflurane alters LA mechanics evaluated with pressure-volume relations.

DESIGN: Prospective.

SETTING: Laboratory.

PARTICIPANTS: Barbiturate-anesthetized dogs (n = 8) were instrumented for measurement of aortic, LA, and LV pressures (micromanometers), and LA volume (epicardial orthogonal sonomicrometers) after 3 weeks of rapid ventricular pacing (220 beats/min).

INTERVENTIONS: LA myocardial contractility (E(es)) was assessed with end-systolic pressure-volume relations. LA stroke work and reservoir function were assessed by A and V loop area, respectively, from the steady-state pressure-volume diagram. LA-LV coupling was determined by the ratio of E(es) to LV elastance (E(LV)). Dogs received 0.6, 0.9, and 1.2 minimum alveolar concentration isoflurane in a random manner, and LA function was determined after a 20-minute equilibration at each dose.

MEASUREMENTS AND MAIN RESULTS: Isoflurane significantly (p < 0.05) decreased heart rate, mean arterial pressure, LV end-systolic pressure, and LV +dP/dt(max). Isoflurane produced dose-related reductions in E(es) and E(es)/E(LV). Declines in LA stroke work, emptying fraction, reservoir volume, V loop area, and the active LA contribution to LV filling also occurred.

CONCLUSIONS: The results indicate that isoflurane depresses LA myocardial contractility, impairs LA-LV coupling, and reduces active LA contribution to LV filling in dogs with pacing-induced cardiomyopathy. The impact of isoflurane on LA function in the presence of LV dysfunction has profound effects on cardiac performance.

Author List

Kehl F, Ladisa JF Jr, Hettrick DA, Kersten JR, Warltier DC, Pagel PS

Author

John F. LaDisa PhD Professor in the Pediatrics department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Anesthetics, Inhalation
Animals
Atrial Function, Left
Blood Pressure
Cardiac Pacing, Artificial
Cardiac Volume
Cardiomyopathies
Disease Models, Animal
Dogs
Dose-Response Relationship, Drug
Heart Rate
Isoflurane
Prospective Studies
Ventricular Dysfunction, Left
Ventricular Pressure