Perfusion-metabolic myocardial scintigraphy in prognosis of left ventricular remodeling after complex surgical treatment of ischemic cardiomyopathy

Abstract

Purpose. To study capabilities of perfusion-metabolic myocardial scintigraphy for prediction of the left ventricular (LV) reverse remod- eling after comprehensive surgical treatment of ischemic cardiomyopathy (ICMP). Methods. The study included ICMP patients aged 56±7 years (n=32) who underwent surgical correction of LV dysfunction (myocardial revascularization, LV reconstruction, and mi- tral valve restoration). Inclusion criteria were significant coronary artery disease; myocardial infarction; New York Heart Association (NYHA) class III–IV heart failure; LV ejection fraction (EF) ≤45%; LV end-systolic index (ESI) >60 mL/m2; and LV akinesia or dys- kinesia according to echocardiography. Before surgery all patients were subjected to scintigraphy with 99mTc-MIBI (to assess perfusion) and with 123I-BMIPP (to assess myocardial metabolism). Scintigraphy results were expressed as median and lower; upper quartile (Me [lQ; hQ]). The clinical status and ventricular volume indicators were evaluated before surgery, in the early post-operative period (up to 4 weeks), and in the late post-operative period (12 months). Results. At 12 months after intervention patients were divided into two groups: group 1 comprised patients (n=18) with beneficial outcome of the operation that stopped LV remodeling (ESI decreased, remained unchanged, or increased by <15% compared with early postoperative period. Group 2 comprised patients (n=14) in whom LV remodeling progressed despite successful surgery (ESI increased ≥15% compared with early postoperative period). Groups did not significantly differ by preoperative echocardiography data and clinical status. Significant differences were found in the following scinti- graphic parameters: metabolic defect on delayed images (26.5% [20.6%; 32.4%] vs. 38.2% [16.2%; 44.1%], p=0.02), and perfusion- metabolic mismatch (PMM) on early (5.9% [- 5.9%; 7.4%] vs. 1.5% [- 7.4%, 1.5%], p=0.02,) and on delayed (14.7% [5.9%; 27.9%] vs. 4.4% [2.9%; 7.4%], p <0.0001) scans in groups 1 and 2, respectively. PMM on delayed scans had the largest area under the ROC- curve (AUC=0.778, p<0.0001). PMM cutoff value of 12% allowed to predict the efficacy of comprehensive surgical treatment for LV dysfunction with sensitivity and specificity of 100 and 56%, respectively. Conclusion. In patients with ICMP results of myocardial perfusion-metabolic scintigraphy can be used in prognostication of reverse cardiac remodeling in the postoperative period.