IMPACT OF PLATELET-FIBRIN CLOT STRENGTH ON OCCURRENCE OF IN-STENT RESTENOSIS IN PATIENT WITH DRUG ELUTING STENT

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. (High Platelet Inhibition With Ticagrelor to Improve Left Ventricular Remodeling in Patients With ST Segment Elevation Myocardial Infarction [HEALING-AMI]; NCT02224534).

Rationale and Design of the High Platelet Inhibition with Ticagrelor to Improve Left Ventricular Remodeling in Patients with ST-Segment Elevation Myocardial Infarction (HEALING-AMI) Trial

BACKGROUND AND OBJECTIVES

Impaired recovery from left ventricular (LV) dysfunction is a major prognostic factor after myocardial infarction (MI). Because P2Y₁₂ receptor blockade inhibits myocardial injury, ticagrelor with off-target properties may have myocardial protection over clopidogrel. In animal models, ticagrelor vs. clopidogrel protects myocardium against reperfusion injury and improves remodeling after MI. We aimed to investigate the effect of ticagrelor on sequential myocardial remodeling process after MI.

METHODS

High platelet inhibition with ticagrelor to improve LV remodeling in patients with ST-segment elevation MI (HEALING-AMI) is an investigator-initiated, randomized, open-label, assessor-blinded, multi-center trial done at 10 sites in Korea. Patients will be enrolled if they have ST-segment elevation MI (STEMI) treated with primary percutaneous coronary intervention and a planned duration of dual antiplatelet treatment of at least 6 months. Screened patients will be randomly assigned (1:1) using an internet-based randomization with a computer-generated blocking with stratification across study sites to either ticagrelor or clopidogrel treatment. The co-primary primary endpoints are LV remodeling index with three-dimensional echocardiography and the level of N-terminal prohormone B-type natriuretic peptide (NT-proBNP) at 6 months representing post-MI remodeling processes. Changes of LV end-systolic/diastolic volume indices and LV ejection fraction between baseline and 6-month follow-up will be also evaluated. Analysis is per protocol.

CONCLUSIONS

HEALING-AMI is testing the effect of ticagrelor in reducing adverse LV remodeling following STEMI. Our trial would show the benefit of ticagrelor vs. clopidogrel related to the recovery of post-MI LV dysfunction beyond potent platelet inhibition.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02224534.