Initial effects of the left ventricular repair by plication may not last long in a rat ischemic cardiomyopathy model.
BACKGROUND
Long term effects of left ventricle (LV) repair surgery (LVR) for ischemic cardiomyopathy are not well understood.


RESULTS
Sixty-nine rats developed ischemic cardiomyopathy with large akinetic LV area 4 weeks after the left anterior descending artery was ligated. In a second surgery 4 weeks later, 33 rats underwent LVR by plication of the akinetic LV area (LVR group), and 36 underwent rethoracotomy alone (sham group). No medication was used in either group. All rats survived the second surgery. LV end-diastolic dimension as measured by echocardiography, LV fractional shortening, and the maximal end-systolic pressure-volume relationship (E(max)) as calculated from the data by catheter-tipped manometer and echocardiography improved in the LVR group after the second surgery, but LV end-diastolic dimension and E(max) gradually deteriorated as time passed. LV end-diastolic pressure improved 1 week after LVR but rose significantly 4 weeks after LVR. Brain natriuretic peptide mRNA was lower in the LVR group than in the sham group 1 week after LVR but not 4 weeks postoperatively.


CONCLUSIONS
Initial improvement in LV function and neurohormonal status after LVR did not last for 4 weeks in this rat model when untreated medically. The mechanism of deterioration should be elucidated to improve long-term results of LVR.
Nishina
T
T
Department of Cardiovascular Surgery, Kyoto University Graduate of School of Medicine, Kyoto, Japan.
Nishimura
K
K
Yuasa
S
S
Miwa
S
S
Nomoto
T
T
Sakakibara
Y
Y
Handa
N
N
Hamanaka
I
I
Saito
Y
Y
Komeda
M
M
D000818:Animals; D006348:Cardiac Surgical Procedures; D009202:Cardiomyopathies / Q000150:complications / Q000503:physiopathology / Q000601:surgery*; D004195:Disease Models, Animal; D018450:Disease Progression; D004452:Echocardiography; D006352:Heart Ventricles / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D006439:Hemodynamics; D008297:Male; D017202:Myocardial Ischemia / Q000150:complications / Q000503:physiopathology / Q000601:surgery*; D009206:Myocardium / Q000378:metabolism; D020097:Natriuretic Peptide, Brain / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D013318:Stroke Volume; D013995:Time; D017211:Treatment Failure; D018487:Ventricular Dysfunction, Left / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology
D012333:RNA, Messenger; D020097:Natriuretic Peptide, Brain