Validation of the HCM Risk-SCD model in patients with hypertrophic cardiomyopathy following alcohol septal ablation
Abstract
Aims The HCM Risk-SCD model for prediction of sudden cardiac death (SCD) in hypertrophic cardiomyopathy recom- mended by the 2014 European Society of Cardiology (ESC) guidelines has not been validated after septal reduction therapy. The aim of this study was to validate the HCM Risk-SCD model in patients undergoing alcohol septal ablation (ASA) and to compare its performance to previous models.
Methods and results A total of 844 ASA patients without prior SCD event were included. The primary endpoint was a composite of SCD and result and appropriate implantable cardioverter defibrillator (ICD) therapy, identical to the HCM Risk-SCD endpoint.
A distinction between periprocedural (30 days) SCD was made to discern procedure-related adverse arrhythmic events caused by the ASA-induced myocardial infarction from long-term SCD risk. Twenty patients reached the SCD endpoint within the first 30 days.
During a follow-up of 6.5 +/- 4.2 years, another 46 patients reached the SCD endpoint. The predicted 5-year SCD risk according to the HCM Risk-SCD model was 5.1%, and the observed 5-year SCD risk was 4.0%.
The C-statistics for the use of the HCM Risk-SCD model was 0.61 (P = 0.02), the C-statistics for the use of the 2003 American College of Cardiology/ESC guidelines was 0.59 (P= 0.051), and the C-statistic for the use of the 2011 American College of Cardiology Foundation/American Heart Association guidelines was 0.58 (P= 0.054). Maximal left ventricular wall thickness, syncope after ASA, and fulfilling the 2014 ESC recommendations for primary ICD implantation according to the HCM Risk-SCD model, respectively, predicted SCD during tong-term follow-up.
Conclusion The HCM Risk-SCD model can be used for SCD prediction in patients undergoing ASA.