The pig as a model of tachycardia and dilated cardiomyopathy.
Chronic Supraventricular Tachycardia (SVT) can produce a dilated cardiomyopathy which has a poorly understood association with ventricular dysfunction in humans and animals. The purpose of this study was to produce a model of chronic SVT and dilated cardiomyopathy using swine, which have a cardiac anatomy similar to man. Eight pigs were implanted with chronic atrial catheters and a pacemaker, with four additional sham-operated pigs serving as controls. We examined ventricular function and morphology at baseline (120 +/- 3 bpm), pacing baseline (240 bpm), and at 1, 2 and 3 weeks of rapid atrial pacing (240 bpm). Ventricular ejection fractions fell significantly from baseline following 1 week (left: 38 +/- 3% vs baseline 61 +/- 1%; right: 31 +/- 5% vs baseline 56 +/- 1%; p less than 0.05) and deteriorated further by 3 weeks of SVT (left: 26 +/- 4%, right: 19 +/- 3%; p less than 0.05). Significant biventricular chamber dilation developed by 2 weeks of SVT (left: 50 +/- 5 cc vs paced baseline 27 +/- 2 cc; right: 67 +/- 6 cc vs paced baseline 28 +/- 3 cc; p less than 0.05) and continued to increase by week 3 of SVT (left: 66 +/- 11 cc; right: 78 +/- 8 cc; p less than 0.05). Five additional paced pigs, without chronic atrial catheters, were followed using echocardiography.(ABSTRACT TRUNCATED AT 250 WORDS)
Hendrick
D A
DA
Department of Surgery, Medical University of South Carolina, Charleston.
Smith
A C
AC
Kratz
J M
JM
Crawford
F A
FA
Spinale
F G
FG
D000818:Animals; D001794:Blood Pressure; D002304:Cardiac Pacing, Artificial; D002311:Cardiomyopathy, Dilated / Q000150:complications / Q000209:etiology* / Q000503:physiopathology; D002408:Catheters, Indwelling; D002908:Chronic Disease; D004195:Disease Models, Animal; D006321:Heart / Q000502:physiology; D013318:Stroke Volume; D013552:Swine; D013617:Tachycardia, Supraventricular / Q000150:complications* / Q000503:physiopathology; D016276:Ventricular Function / Q000502:physiology