Remodeling of left ventricle in patients undergoing off pump cardiac surgery: preliminary data

Abstract

Dyskinetic areas of myocardium wall, defined as areas of scar tissue with patches of viable myocardium, are commonly encountered in clinical practice. It is well known that these areas constitute a susceptible substrate for the genesis of malignant ventricular tachyarrhythmias. In the present study, we describe a new technique of external left ventricular (LV) reshaping, soughting this way to obtain a near normal shape on a beating heart operation, by isolation of dyskinetic areas. Following total arterial revascularization without aortic manipulations, on a beating heart operation, the heart was appropriately positioned and the dilated area was identified. Using continuous sutures, reinforced by pledged strips, the defined area was plicated effectively, excluding it from the contractile tissue. 751 pts, underwent off-pump myocardial revascularization from September 2001 to August 2004. The external reshaping technique was applied on thirty six (32 M, 4F, mean ± SD age 64.2 ± 12.3) cases (4.8%). Mean LVEF was 31.2±7%. Plication was performed on the lateral wall in 16 pts and on inferior and anterolateral wall in 5 and 15 pts respectively. A mitral valve insufficiency of 2+ −3+/4+ was revealed in 14 pts. The geometry of LV was almost normalized and the end diastolic volume was reduced. A slight elevation of troponin-1 levels was observed to the whole study population. 1 pt died due to severe RV dysfunction. 3 pts experienced ventricular extrasystols, well tolerated and successfully responded to intravenous administration of amiodarone. Episodes of malignant ventricular tachyarrhythmias were not recorded. Postoperative echocardiographic data compared to those preoperatively, revealed a reduction of LV end-diastolic diameter and a statistically significant improvement of LV systolic function (LVEF 42.2±4% vs. 31.2±7% respectively) as well. Reduction of mitral valve insufficiency was observed in 13/14 pts. The external reshaping of LV, on a beating heart surgery, is technically feasible, without major complications. Normalization of LV geometry results in amelioration of LV systolic function. Isolation of dyskinetic areas could possibly reduce the incidence of VT episodes these pts often experience. Further and more detailed study is necessary to confirm our results.