Effect of Ticagrelor on Left Ventricular Remodeling in Patients With ST-Segment Elevation Myocardial Infarction (HEALING-AMI)

Objectives: The aim of this study was to evaluate the effect of ticagrelor versus clopidogrel on left ventricular (LV) remodeling after reperfusion of ST-segment elevation myocardial infarction (STEMI) in humans. Background: Animal studies have demonstrated that ticagrelor compared with clopidogrel better protects myocardium against reperfusion injury and improves remodeling after myocardial infarction. Methods: In this investigator-initiated, randomized, open-label, assessor-blinded trial performed at 10 centers in Korea, patients were enrolled if they had naive STEMI successfully treated with primary percutaneous coronary intervention (PCI) and at least 6-month planned duration of dual-antiplatelet treatment. The coprimary endpoints were LV remodeling index (LVRI) (a relative change of LV end-diastolic volume) measured on 3-dimensional echocardiography and N-terminal pro–B-type natriuretic peptide level at 6 months. Results: Among initially enrolled patients with STEMI (n = 336), 139 in each group completed the study. LVRI at 6 months was numerically lower with ticagrelor versus clopidogrel (0.6 ± 18.6% vs. 4.5 ± 16.5%; p = 0.095). Ticagrelor significantly reduced the 6-month level of N-terminal pro–B-type natriuretic peptide (173 ± 141 pg/ml vs. 289 ± 585 pg/ml; p = 0.028). These differences were prominent in patients with pre-PCI TIMI (Thrombolysis In Myocardial Infarction) flow grade 0. By multivariate analysis, ticagrelor versus clopidogrel reduced the risk for positive LV remodeling (LVRI >0%) (odds ratio: 0.56; 95% confidence interval: 0.33 to 0.95; p = 0.030). The LV end-diastolic volume index remained unchanged during ticagrelor treatment (from 54.7 ± 12.2 to 54.2 ± 12.2 ml/m²; p = 0.629), but this value increased over time during clopidogrel treatment (from 54.6 ± 11.3 to 56.4 ± 13.9 ml/m²; p = 0.056) (difference −2.3 ml/m²; 95% confidence interval: −4.8 to 0.2 ml/m²; p = 0.073). Ticagrelor reduced LV end-systolic volume index (from 27.0 ± 8.5 to 24.7 ± 8.4 ml/m²; p < 0.001), whereas no reduction was seen with clopidogrel (from 26.2 ± 8.9 to 25.6 ± 11.0 ml/m²; p = 0.366) (difference −1.8 ml/m²; 95% confidence interval: −3.5 to −0.1 ml/m²; p = 0.040). Conclusions: Ticagrelor was superior to clopidogrel for LV remodeling after reperfusion of STEMI with primary PCI.