Prognostic utility of atrial cardiomyopathy, HFA-PEFF, and H2FPEF scores in patients with sick sinus syndrome

Background Sick sinus syndrome (SSS) is closely associated with atrial fibrillation (AF) and heart failure with preserved ejection fraction (HFpEF), which are now increasingly recognized as manifestations of atrial cardiomyopathy (AtCM). While the HFA-PEFF and H2FPEF scores were originally developed to aid in the diagnosis of HFpEF, their prognostic value in SSS patients remains unknown. Moreover, simplified tools for clinical risk stratification are warranted in this population. Objective To assess the prognostic utility of the HFA-PEFF and H2FPEF scores and to validate a simplified Atrial Cardiomyopathy (AtCM) score for predicting cardiovascular outcomes and AF burden in patients with SSS and preserved left ventricular ejection fraction (LVEF) after pacemaker implantation. Purpose We prospectively enrolled 206 patients with SSS and preserved LVEF following dual-chamber pacemaker implantation. Patients were randomized 1:1 into derivation and validation cohorts. HFA-PEFF, H2FPEF, and AtCM scores were calculated two days after implantation using echocardiographic and laboratory parameters. The primary outcome was a composite of cardiovascular events over three years. Secondary outcomes included AF episodes ≥7 days. Kaplan–Meier, Cox regression, and ROC analyses were performed to compare prognostic performance. Results In the derivation cohort, both the HFA-PEFF score (HR: 1.89; 95% CI: 1.18–3.02; P = 0.008) and the AtCM score (HR: 1.99; 95% CI: 1.34–2.94; P < 0.001) were significantly associated with 3-year cardiovascular events, whereas the H2FPEF score was not. The C-statistics were 0.77 for the AtCM score and 0.71 for the HFA-PEFF score. In the validation cohort, patients with an AtCM score ≥4 had a 3-year cardiovascular event rate of 26.2% versus 8.9% for those with a score <4 (P = 0.025). Persistent AF (≥7 days) occurred in 34.1% of patients with AtCM scores ≥4 versus 9.3% with lower scores (P = 0.004). The AtCM score remained an independent predictor of both cardiovascular events and AF burden in multivariate models. Conclusions The AtCM score, based on four parameters (E/e′, TRPG, LAVI, and BNP), is a simplified and robust predictor of adverse cardiovascular outcomes and persistent AF in SSS patients with preserved LVEF after pacemaker implantation. Compared with the HFA-PEFF and H2FPEF scores, the AtCM score demonstrated superior prognostic accuracy and practicality, particularly in elderly, low-BMI populations. These findings support the clinical utility of AtCM-based risk stratification in long-term management of SSS.