Myocardial effects of ventricular fibrillation in the isolated rat heart

被引:37
作者
Gazmuri, RJ
Berkowitz, M
Cajigas, H
机构
[1] N Chicago VA Med Ctr, Med Serv, Pulm & Crit Care Med Sect, N Chicago, IL 60064 USA
[2] Finch Univ Hlth Sci Chicago Med Sch, Dept Med, Div Pulm & Crit Care Med, N Chicago, IL 60064 USA
关键词
ventricular fibrillation; arrest; myocardial ischemia; electrical countershock; ventricular dysfunction; diastole; myocardial stunning; cardiopulmonary resuscitation;
D O I
10.1097/00003246-199908000-00023
中图分类号
R4 [临床医学];
学科分类号
1002 ; 100602 ;
摘要
Objective: Ventricular fibrillation (VF) is known to increase myocardial oxygen requirements and to alter coronary vascular physiology, However, the significance of these effects during cardiac arrest and resuscitation is not well understood. A model was developed in the isolated rat heart to investigate the myocardial effects of VF during a simulated episode of cardiac arrest and resuscitation, We hypothesized that VF would intensify the severity of myocardial ischemia and consequently accentuate postischemic myocardial dysfunction. Design: Prospective and randomized. Setting: Research laboratory. Subjects: Twenty Sprague-Dawley rats. Interventions: Hearts were harvested and perfused at a constant flow rate of 10 mL/min using a modified Krebs-Henseleit solution equilibrated with 95% oxygen and 5% CO2. In five hearts, VF was induced by a 0.05-mA current delivered to the right ventricular endocardium. The perfusate flow was then stopped for a 10-min interval and resumed at 20% of baseline flow for another 10 mins, After 20 mins of VF, the perfusate flow was returned to baseline and a sinus rhythm reestablished by epicardial electrical shocks. The studies were randomized and included three additional groups to control for the effects of ischemia without VF (n = 5), the effects of VF without ischemia (n = 5), and the stability of the preparation (n = 5). Measurements and Main Results: Isovolumic indices of left ventricular function were obtained using a latex balloon advanced through the mitral valve and distended to an end-diastolic pressure of 10 mm Hg. The coronary effluent was collected from the right ventricular cavity. YF during myocardial ischemia was associated with a higher coronary effluent PCO2, increased coronary vascular resistance, and development of ischemic contracture as indicated by Increases in left ventricular pressure from 9 +/- 3 to 33 +/- 6 mm Hg (p < .05). After defibrillation, contractility and relaxation rapidly returned to baseline values, whereas the isovolumic end-diastolic pressure remained elevated for 20 mins, These changes were much less prominent when ischemia was not accompanied by YF. Conclusions: These findings indicate that VF may adversely affect myocardial ischemia by hastening the development of ischemic contracture, increasing coronary vascular resistance, and favoring the development of diastolic pump failure early after resuscitation from cardiac arrest.
引用
收藏
页码:1542 / 1550
页数:9
相关论文
共 49 条
[1]  
ANDERSON PG, 1987, AM J PATHOL, V129, P152
[2]   ATTENUATION OF POSTISCHEMIC DYSFUNCTION BY ISCHEMIC PRECONDITIONING IS NOT MEDIATED BY ADENOSINE IN THE ISOLATED RAT-HEART [J].
ASIMAKIS, GK ;
INNERSMCBRIDE, K ;
CONTI, VR .
CARDIOVASCULAR RESEARCH, 1993, 27 (08) :1522-1530
[3]   Preconditioning ischemia time determines the degree of glycogen depletion and infarct size reduction in rat hearts [J].
Barbosa, V ;
Sievers, RE ;
Zaugg, CE ;
Wolfe, CL .
AMERICAN HEART JOURNAL, 1996, 131 (02) :224-230
[4]   RELAXATION IN RABBIT AND RAT CARDIAC-CELLS - SPECIES-DEPENDENT DIFFERENCES IN CELLULAR MECHANISMS [J].
BASSANI, JWM ;
BASSANI, RA ;
BERS, DM .
JOURNAL OF PHYSIOLOGY-LONDON, 1994, 476 (02) :279-293
[5]   CORONARY BLOOD-FLOW DURING CARDIOPULMONARY RESUSCITATION IN SWINE [J].
BELLAMY, RF ;
DEGUZMAN, LR ;
PEDERSEN, DC .
CIRCULATION, 1984, 69 (01) :174-180
[6]   ACTIVATION OF BLOOD-COAGULATION AFTER CARDIAC-ARREST IS NOT BALANCED ADEQUATELY BY ACTIVATION OF ENDOGENOUS FIBRINOLYSIS [J].
BOTTIGER, BW ;
MOTSCH, T ;
BOHRER, H ;
BOKER, T ;
AULMANN, M ;
NAWROTH, PP ;
MARTIN, E .
CIRCULATION, 1995, 92 (09) :2572-2578
[7]   IMPROVING SURVIVAL FROM SUDDEN CARDIAC-ARREST - THE CHAIN OF SURVIVAL CONCEPT - A STATEMENT FOR HEALTH-PROFESSIONALS FROM THE ADVANCED CARDIAC LIFE-SUPPORT SUBCOMMITTEE AND THE EMERGENCY CARDIAC CARE COMMITTEE, AMERICAN-HEART-ASSOCIATION [J].
CUMMINS, RO ;
ORNATO, JP ;
THIES, WH ;
PEPE, PE ;
BILLI, JE ;
SEIDEL, J ;
JAFFE, AS ;
FLINT, LS ;
GOLDSTEIN, S ;
ABRAMSON, NS ;
BROWN, C ;
CHANDRA, NC ;
GONZALEZ, ER ;
NEWELL, L ;
STULTS, KR ;
MEMBRINO, GE .
CIRCULATION, 1991, 83 (05) :1832-1847
[8]   REVERSIBLE MYOCARDIAL DEPRESSION IN SURVIVORS OF CARDIAC-ARREST [J].
DEANTONIO, HJ ;
KAUL, S ;
LERMAN, BB .
PACE-PACING AND CLINICAL ELECTROPHYSIOLOGY, 1990, 13 (08) :982-985
[9]   FAILURE OF EPINEPHRINE TO IMPROVE THE BALANCE BETWEEN MYOCARDIAL OXYGEN-SUPPLY AND DEMAND DURING CLOSED-CHEST RESUSCITATION IN DOGS [J].
DITCHEY, RV ;
LINDENFELD, J .
CIRCULATION, 1988, 78 (02) :382-389
[10]   CARDIAC DAMAGE PRODUCED BY DIRECT-CURRENT COUNTER-SHOCK APPLIED TO THE HEART [J].
DOHERTY, PW ;
MCLAUGHLIN, PR ;
BILLINGHAM, M ;
KERNOFF, R ;
GORIS, ML ;
HARRISON, DC .
AMERICAN JOURNAL OF CARDIOLOGY, 1979, 43 (02) :225-232