Extracorporeal cardiac shock wave therapy improves left ventricular remodeling after acute myocardial infarction in pigs.
OBJECTIVE
We have recently demonstrated that low-energy extracorporeal shock wave therapy improves chronic myocardial ischemia in pigs and humans. In this study, we examined whether our shock wave therapy is also effective at improving left ventricular remodeling after acute myocardial infarction in pigs.


METHODS
Acute myocardial infarction was created by surgically excising the proximal segment of the left circumflex coronary artery (n=20). In the early treatment protocol, the shock wave therapy was started 3 days after acute myocardial infarction, whereas in the late treatment protocol, the therapy was started 4 weeks after acute myocardial infarction (n=5 each). The remaining animals were treated in the same manner, but without the shock wave treatment in each protocol (n=5 each).


RESULTS
In the early treatment protocol, left ventricular ejection fraction was higher (42+/-1 vs. 32+/-1%, P<0.001) and left ventricular end-diastolic volume was smaller (95+/-1 vs. 99+/-2 ml, P<0.05) in the shock wave group compared with the control group. Furthermore, wall thickening fraction (32+/-1 vs. 28+/-1%, P<0.01), regional myocardial blood flow (1.7+/-0.2 vs. 1.0+/-0.1 ml/min/g, P<0.01), and number of capillaries in the border zone (1348+/-15 vs. 938+/-34 mm2, P<0.0001) were all significantly improved in the shock wave group compared with the control group. By contrast, in the late treatment group, no such beneficial effects of the shock wave therapy were noted.


CONCLUSIONS
These results suggest that our extracorporeal cardiac shock wave therapy is also an effective and noninvasive therapy for improving left ventricular remodeling after acute myocardial infarction when started in the early phase of the disorder.
Uwatoku
Toyokazu
T
Department of Cardiovascular Medicine, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.
Ito
Kenta
K
Abe
Kohtaro
K
Oi
Keiji
K
Hizume
Takatoshi
T
Sunagawa
Kenji
K
Shimokawa
Hiroaki
H
D000818:Animals; D017023:Coronary Angiography; D003326:Coronary Circulation; D004195:Disease Models, Animal; D004452:Echocardiography; D015637:Gated Blood-Pool Imaging; D019220:High-Energy Shock Waves / Q000627:therapeutic use*; D008297:Male; D009203:Myocardial Infarction / Q000175:diagnosis / Q000503:physiopathology / Q000532:radiotherapy*; D012720:Severity of Illness Index; D013552:Swine; D016896:Treatment Outcome; D016277:Ventricular Function, Left / Q000502:physiology*; D020257:Ventricular Remodeling / Q000502:physiology*