Performance of the 2020 ACC/AHA and 2023 ESC risk stratification scales for primary prevention of sudden cardiac death in a Latin American population with hypertrophic cardiomyopathy

Identifying patients with hypertrophic cardiomyopathy (HCM) who are at high risk of sudden cardiac death (SCD) is essential for managing this condition. The American Heart Association/American College of Cardiology (AHA/ACC) and European Society of Cardiology (ESC) guidelines help assess and stratify the risk of determining which patients would benefit from primary prevention with an implantable cardioverter-defibrillator (ICD).

The study aims to evaluate the performance of the 2020 AHA/ACC and 2023 ESC risk stratification scales (AHA/ACC-rss; ESC-rss) for the primary prevention of SCD in Latin-American patients diagnosed with HCM.

A retrospective cohort of HCM from a single-center was analyzed. The inclusion criteria were individuals aged 16 years or older, without a history of SCD, and who had not undergone any treatment such as myomectomy or septal ablation with alcohol (Figure 1). The primary outcome was the identification of SCD or an equivalent event (successful resuscitation after cardiac arrest or appropriate therapy from the ICD).

One hundred twenty patients were included (mean age 46.2 years old) and the mean follow-up duration was 61.1 months. From the total sample, 10 patients (8.3%) experienced an equivalent SCD event; 7 patients (5.8%) were ICD-protected and 3 (2.5%) required external defibrillation. The ESC-rss showed a greater area under the ROC curve (AUC, 0.79; 95% CI 0.62-0.94 vs AUC, 0.63; 95% CI 0.49-0.78) and specificity (85%; 95% CI 63-92 vs 51%; 95% CI 37.3-64.5). Sensitivity was similar between both scales (AHA/ACC-rss: 77%; 95% CI 50-100 vs ESC-rss: 73%; 95% CI 43-100). Remarkably, 2.5% of the patients who experienced an equivalent of SCD were incorrectly identified as low-risk individuals by either the AHA/ACC-rss, ESC-rss, or both (Table 1).

The SCD risk stratification recommended by the ESC-rss demonstrated a more effective identification of Latin American patients with HCM for ICD placement because the area under the curve was more significant than those of the AHA/ACC-rss. This single-center study highlights the need for a multicenter prospective study in Latin America.