Clinical characteristics of the study population are summarized in table . Thirty-five patients were revascularized (26 CABG, 9 PCI patients). Clinical follow-up over a period of 20 ± 16 months (minimum period was 1 month, maximum period was 56 months) was obtained in all patients. Twenty-four of the 86 patients (28%) had 2 vessel disease (left main, or two vessel with proximal left anterior descending artery), and 49 patients (57%) had 3 vessel disease. During the follow-up period, 33 patients (38%) had cardiovascular events (mean follow-up period was 20 ± 16 months). Fifteen patients of the 33 patients had CHF, 9 patients had ventricular arrhythmia, 2 patients had syncope, 2 patients had MI, 5 patients needed revascularization and 6 patients died due to cardiovascular cause during the follow-up period. There were any deaths or events were related to revascularization procedures.
Clinical profile of patients
Cardiac magnetic resonance parameters to predict cardiovascular events
CMR parameters among the patients ± cardiovascular events are summarized in table . Both mean scar volume and scar percentage of the myocardium were larger in patients with cardiovascular events than those without cardiovascular events (16.8 ± 12.4 cm3 vs. 11.7 ± 12.6 cm3, p = 0.023 and 10.2 ± 6.9% vs. 7.2 ± 6.7%, p = 0.037, respectively). There were no significant differences in LVEDV, LVESV and LVEF between the patients with and without cardiovascular events (234 ± 76 ml vs. 230 ± 88 ml, 180 ± 73 ml vs. 175 ± 90 ml, 25 ± 10% vs. 27 ± 13%, respectively).
Predictors of cardiovascular events
The transmurality of the scar was also analyzed by dividing into non-transmural vs. transmural extent of MI (1–75% vs. 76–100%, respectively) among the patients as shown in table . Patients with cardiovascular events had larger number of non-transmural segments than patients without cardiovascular events (18.4 ± 14.0% vs. 13.8 ± 11.2%, p = 0.049). Specifically, higher incidences of cardiovascular events were seen in the 26–50% non-transmural segments (9.2 ± 10.6% vs. 3.2 ± 3.6%, p = 0.03). In subanalysis, there were no significant difference in the number of both non-transmural segments and transmural segment in patients with and without ventricular arrhythmia (p = 0.71, p = 0.64, respectively). In addition, there were no significant difference in the number of both non-transmural segment and transmural segment in patients with and without worsening CHF (p = 0.94, p = 0.06, respectively).
The proportion of non-transmural vs. transmural segments of myocardial infarction
Correlation between scar characteristics and functional parameters
The correlation of LVEF, LVEDV and LVESV with scar volume and scar percentage of the myocardium is shown in figure , , (figure : LVEF, figure : LVEDV, figure : LVESV). These measurements did not correlate with scar volume with r values of 0.16, 0.08 and 0.10, respectively and did not correlate with scar percentage of the myocardium with r values of 0.08, 0.01 and 0.02, respectively.
The correlation between left ventricular volumes and the scar volume and scar percentage. The correlation of LVEF with scar volume (a) and scar percentage of the myocardium (b).
The correlation between left ventricular volumes and the scar volume and scar percentage. The correlation of LVEDV with scar volume (a) and scar percentage of the myocardium (b).
The correlation between left ventricular volumes and the scar volume and scar percentage. The correlation of LVESV with scar volume (a) and scar percentage of the myocardium (b).
Effects of revascularization
When the patients were analyzed between the revascularization (CABG or PCI ± ICD placement) and the no revascularization groups (medical therapy ± ICD placement), there were more patients with 3 vessel disease and with ICD placement who underwent revascularization (p = 0.02, for each) as shown in table . However, there was no significant difference in both scar volume and percentage of the myocardium between the 2 groups (p = 0.60 and 0.37, respectively). Finally, there was no significant difference in the incidence of cardiovascular events between these two groups (p = 0.24).
Clinical parameters to predict cardiovascular events
Analyses of clinical characteristics of all patients with and without cardiovascular events are summarized in table . There was no significant difference in clinical parameters between these two groups.
Predictors of cardiovascular events