Cardiac Magnetic Resonance to Predict Appropriate Therapies in Secondary Prevention

Abstract Introduction Implantable cardioverter-defibrillator (ICD) therapy plays a pivotal role in the management of patient’s survivors of life-threatening ventricular arrhythmias (secondary prevention). Risk of recurrence may be related to presence of myocardial scar and its components (including core mass, border zone (BZ) mass, and BZ channels) assessed with late gadolinium enhancement cardiac magnetic resonance (LGE-CMR). Purpose Our study aims to analyze the role of imaging in predicting the risk of recurrent ventricular arrhythmias and improving the risk stratification for appropriate ICD therapy in patients receiving an ICD for secondary prevention. Methods From 2015 to 2020, a total of 111 patients with LGE-CMR before ICD implantation for secondary prevention. Scar tissue including core, BZ and BZ channels were automatically detected by specialized investigational software in patients with LGE-CMR. Patients were followed until a new event was detected. Results The mean age was 65.4 ± 11.4 years; 87% were men; 55% had ischemic cardiomyopathy. The mean left ventricular ejection fraction was 37.8 % ± 14.31%. Patients were followed for a median of 3.26 years (IQR 1.4-4.9). Within the first year of follow-up 22% of patients had received an appropriate therapy, 39% within 3 years and 53% within 6 years. Chronic kidney disease and New York Heart Association (NYHA) class were associated with the primary endpoint [HR 1.94(1.06-3.55), P-value 0.032)] and [HR 1.86 (1.19-2.91), P-value 0.006)], respectively. Regarding CMR characteristics, BZ percentage was also associated with appropriate ICD therapy in the follow up [HR 1.04(1-1.08), P-value 0.048)]. Other CMR parameter, such as BZ mass, BZ core %, BZ core mass and core mass showed a trend to predict ICD therapies during follow-up. ROC curve analysis with Youden’s index defined an optimal BZ percentage cutoff value for recurrence prediction of 9.5% [HR 0.49 (0.28-0.85)]. Conclusion In patients receiving an ICD for secondary prevention, chronic kidney disease, NYHA class and BZ percentage analyzed by LGE-CMR were predictors of recurrent ventricular arrhythmia. A cutoff of BZ of 9.5% could be used to select patients with high risk of recurrence.