Early Changes of Left Ventricular Geometry and Function after Surgical Ventricular Restoration and Mitral Valve Annuloplasty: Magnetic Resonance Imaging

PURPOSE: We sought to determine the early change of ventricular geometry and function after concomitant surgeries of modified Dor procedure and mitral valve annuloplasty by using magnetic resonance imaging. MATERIALS AND METHODS: We enrolled 21 patients with dilated heart failure who underwent modified Dor procedure (n=8), mitral valve annuloplasty (n=6), or both surgeries (n=7). Cine MRI was used to assess left ventricular dimensions and function before and after surgery. We measured the left ventricular end-diastolic and end-systolic volumes and the dimensions of the left ventricular long-axis and short-axis. Left ventricular stroke volume, ejection fraction, and sphericity index were calculated from these measurements. These parameters were analyzed and compared between three different surgery groups to explain the combined effect of the concomitant surgeries. RESULTS: MRI was performed within average 12 +/- 15 days (range 1-58 days) before and 38 +/- 50 days (range 7- 231 days) after the surgery. The patients who underwent concomitant surgeries had more profound enlargement of left ventricle and decreased contractility prior to surgery than those in the patients who underwent single surgical procedure. Left ventricular end-diastolic volume and endsystolic volume significantly decreased in all patients regardless of surgery type after surgery. Ejection fraction significantly increased only in the patients who got modified Dor procedure without mitral valve annuloplasty (25.4% to 40.7%). Sphericity index increased in patients with modified Dor procedure but decreased in patients with mitral valve annuloplasty (0.65 to 0.78 vs. 0.75 to 0.65). In the patients who underwent concomitant surgeries showed no significant change in sphericity index after surgery. CONCLUSION: The early change of the left ventricular geometry and function after the concomitant surgeries with modified Dor procedure and mitral valve annuloplasty in patients with dilated heart failure includes a marked reduction in left ventricular volume and in stroke volume. The shape of the left ventricle does not change because the effect of sphericity index decrease from mitral valve annuloplasty is counteracted by the effect of sphericity index increase from modified Dor procedure. Improvement of left ventricular ejection fraction is not the early change after the concomitant surgeries.

Surgical Treatment of Coronary Artery Disease

The main goals of coronary artery bypass grafting (CABG) are to relieve chest pain and to improve quality of life by bypassing all coronary artery segments with severe stenosis. It is a common surgical procedure on the heart. Until recently, most surgeons have used cardiopulmonary bypass (CPB) to provide a motionless and bloodless operation field to accomplish optimal microvascular anastomoses. However, CPB may have adverse sequelae, such as cerebrovascular accident, renal failure, and higher intellectual impairment, because of an inflammatory response caused by the blood circulating through the extracorporeal circuit and the formation of microemboli. In recent years, advances in retractor-stabilizer systems and in operative techniques that allow an access to all coronary artery segments have brought a growing attention to beating heart surgery without CPB (offpump coronary artery bypass grafting, OPCAB). OPCAB significantly lowers in-hospital morbidity and mortality compared with CABG. Heart failure after myocardial infarction poses a growing medical challenge as the life expectancy continues to increase. Recently it affects 0.4~1% of the overall population and 5% of elderly subjects. Although cardiac transplantation, a gold standard surgery for heart failure, provides excellent therapeutic outcomes in some patients with terminal stage of the disease, the overall outcomes are limited by the scarcity of donor organs, reduced long-term survival, and co-morbid conditions. Recently the efficacies of left ventricular volume reduction surgery, mitral valve repair, and bone marrow cell transplantation in improving the heart function in infracted myocardium of a failing heart have been extensively evaluated and were shown to result in good outcomes.