Left ventricular reconstruction in ischemic heart disease

Abstract

Objectives: [1] To review our experience with left ventricular reconstruction (LVR) regarding safety (early mortality and morbidity) and long-term survival (Study I). [2] To evaluate LVR including surgery for ventricular tachycardia in patients with preoperative spontaneous or inducible ventricular tachycardia (Study II). [3] To analyze risk factors for mortality and hospital re-admission for heart failure after LVR (Study III). [4] To prospectively investigate changes in functional status and quality of life after LVR (Study IV). [5] To prospectively investigate changes in biomarkers for heart failure (BNP and NT-pro-BNP) in relation to functional status after LVR (Study V).

Background: Postinfarction cardiac remodeling with left ventricular dilatation is strongly associated with decreased survival. Surgical restoration of left ventricular size and form is proposed to improve survival, functional status, and quality of life.

Methods: In three retrospective studies, 101 (Study I), 53 (Study II), and 136 (Study III) patients were included. Patients were considered for LVR if they demonstrated an enlarged, either dyskinetic or akinetic, left ventricle accompanied by left ventricular dysfunction after myocardial infarction, and had symptoms of angina or heart failure with or without ventricular tachycardia. Survival, morbidity, and freedom from re-hospitalization were ascertained by review of patients records, our institutional database, and national registers. In addition, freedom from postoperative ventricular tachycardia was evaluated by programmed ventricular stimulation in most patients in Study II. Conventional statistical methods were employed to identify factors associated with adverse outcome in Study III. Two prospective studies were conducted to investigate functional status and quality of life (Study IV, n=23) and changes in biomarkers for heart failure (Study V, n=29). Health-related quality of life and functional status was evaluated preoperatively, six months postoperatively, and at late follow-up almost two years after surgery, with the Short Form-36 questionnaire, the six-minute walk test, and New York Heart Association functional class. Blood samples were collected at equivalent timepoints for analysis of biomarkers for heart failure (BNP and NT-pro-BNP).

Results and Conclusions: [1] LVR is a reproducible and safe surgical option in patients with left ventricular aneurysm or ischemic dilated cardiomyopathy. Early mortality was 7.4% and five year survival was 68%. [2] LVR including endocardiectomy and cryoablation resulted in a very high (90%) freedom from spontaneous ventricular tachycardia. [3] LVR resulted in a high degree of freedom from re-admission for heart failure. We found a strong association between increasing grade of preoperative mitral regurgitation and both long-term mortality and re-admission for heart failure. [4] Functional status and health-related quality of life improved six months after LVR and the improvement was sustained at late follow-up. [5] Severe heart failure secondary to postinfarction left ventricular remodeling can be reversed by LVR. Clinical improvement was associated with reduced levels of BNP and NT-pro- BNP six months after surgery. Clinical improvement was maintained and peptide levels were further reduced at late follow-up.