Myocardial infarct heterogeneity assessment by late gadolinium enhancement cardiovascular magnetic resonance imaging shows predictive value for ventricular arrhythmia development after acute myocardial infarction

AIMS: The aim of this study was to assess the association between the proportions of penumbra-visualized by late gadolinium enhanced cardiovascular magnetic resonance imaging (LGE-CMR)-after acute myocardial infarction (AMI) and the prevalence of ventricular tachycardia (VT). METHODS: One-hundred and sixty-two AMI patients, successfully, treated by primary percutaneous coronary intervention (PCI) underwent LGE-CMR after a median of 3 days (3-4) and 24-h Holter monitoring after 1 month. With LGE-CMR, the total amount of enhanced myocardium was quantified and divided into an infarct core (>50% of maximal signal intensity) and penumbra (25-50% of maximal signal intensity). With Holter monitoring, the number of VTs (≥4 successive PVCs) per 24 h was measured. RESULTS: The mean total enhanced myocardium was 31 ± 11% of the left ventricular mass. The % penumbra accounted for 39 ± 11% of the total enhanced area. In 29 (18%) patients, Holter monitoring showed VT, with a median of 1 episode (1-3) in 24 h. A larger proportion of penumbra within the enhanced area increased the risk of VTs OR: 1.06 (95% CI: 1.02-1.10), P = 0.003. After multivariate logistic regression analysis, the presence of ventricular fibrillation before primary PCI OR: 5.60 (95% CI: 1.54-20.29), P = 0.01 and the proportional amount of penumbra within the enhanced myocardium OR: 1.06 (95% CI: 1.02-1.10), P = 0.04 were independently associated with VT on Holter monitoring. CONCLUSION: Larger proportions of penumbra in the subacute phase after AMI are associated with increased risk of developing VTs. Quantification of penumbra size may become a useful future tool for risk stratification and ultimately for the prevention of ventricular arrhythmias.