ISSN 2996-8215
International Journal of Cardiology | Vol. 4, No. 11, November 2013 | pp. 81–88
DOI: 10.46882/2013/IJC/000056
Original Research Article
Prognostic Significance of Myocardial Viability assessed by Cardiac Magnetic Resonance in Patients with Ischemic Cardiomyopathy
Vasily Smirnov¹, Elena Kuzmina², Dmitry Ivanov¹
¹Department of Cardiology, Almazov National Medical Research Centre, St. Petersburg, Russia
²Division of Cardiovascular Imaging, Pavlov First Saint Petersburg State Medical University, St. Petersburg, Russia
Abstract:
In patients with ischemic cardiomyopathy and severely reduced left ventricular function, selecting candidates for surgical revascularization depends on verifying viable myocardium. Late gadolinium enhancement (LGE) cardiac magnetic resonance (CMR) allows for precise quantification of transmural scar extent. This prospective study evaluated the long-term prognostic value of CMR-derived myocardial viability parameters in predicting functional recovery and survival after coronary artery bypass grafting (CABG). We followed 165 patients with chronic coronary artery disease and a baseline LVEF less than or equal to 35% who underwent viability evaluation via LGE-CMR prior to planned CABG. Myocardial segments were classified as viable if the transmural extent of scar tissue was less than or equal to 50%. A significant amount of viable myocardium was defined as greater than or equal to 4 viable segments within a 17-segment model. Patients were tracked over a median of 4.5 years for a composite primary endpoint of cardiac death or heart failure hospitalization. A significant viable myocardium profile was identified in 98 patients (59.4%). At 6 months post-CABG, 78.5% of the viable cohort demonstrated an absolute increase in LVEF greater than or equal to 5%, compared with only 12.0% of the non-viable cohort (p < 0.001). Over the full follow-up period, patients with viable myocardium experienced significantly better event-free survival than non-viable individuals (log-rank p = 0.002). Multivariable Cox regression confirmed that the absolute number of viable segments was an independent predictor of long-term survival (hazard ratio: 0.78 per segment, 95% CI: 0.66–0.92, p = 0.004). Quantitative scar characterization via late gadolinium enhancement CMR effectively predicts functional recovery and long-term event-free survival in patients with ischemic cardiomyopathy undergoing surgical revascularization.
Keywords: Ischemic cardiomyopathy, Myocardial viability, Cardiac magnetic resonance, Late gadolinium enhancement, Coronary artery bypass grafting, Prognosis
Received: August 10, 2013; Revised: September 22, 2013; Accepted: October 14, 2013; Published: November 20, 2013
Citation: International Journal of Cardiology, 2013, Vol. 4, No. 11, pp. 81–88, DOI: 10.46882/2013/IJC/000056