Gulf of Tomini Cardiac Arrhythmia Research and Exploration (G-CARE): A Multicenter Hospital-Based Outpatient ECG Study

Siregar, Muchtar Nora Ismail
Yusuf, Zuhriana K.
Iman, Dian Pratiwi
Djakaria, M. Yusril Ihza

Indonesian Journal of Cardiology
Vol 47 No 1 (2026): January - March, 2026

Introduction: Cardiac arrhythmias pose a significant burden on global health, especially in underserved regions with limited access to diagnostics. In Indonesia, particularly in the Gulf of Tomini, epidemiologic data on arrhythmia prevalence are scarce. Methods: The G-CARE (Gulf of Tomini Cardiac Arrhythmia Research and Exploration) study was a hospital-based, multicenter, cross-sectional study conducted from 2023–2025 across four referral centers in Gorontalo Province. Adults aged ≥18 years who underwent 12-lead ECG examination were included through purposive sampling. ECGs were interpreted by board-certified cardiologists and classified by arrhythmia type. Results: A total of 3,177 patients were included (mean age: 53.9±14.9 years; 54.6% female). Normal ECGs were found in 43.4%. The most common abnormalities were ischemic ST-T changes (18.9%, 95% CI: 17.5–20.3), QTc prolongation (15.5%, 95% CI: 14.2–16.8), and left ventricular hypertrophy (10.1%, 95% CI: 9.1–11.2). Atrial fibrillation/flutter occurred in 3.5% (95% CI: 2.8–4.3), AV block in 3.7% (95% CI: 3.0–4.5), and Brugada Pattern in 0.4% (95% CI: 0.2–0.8). Age-related increases were observed for AF, AV block, and QT prolongation. PVC morphology showed high-risk features (QRS >160 ms, coupling interval <300 ms) in young adults. Conclusion: The G-CARE study identifies a high prevalence of electrocardiographic abnormalities among adults undergoing ECG in outpatient settings within the Gulf of Tomini region. Because the study used hospital-based, purposive sampling of patients who had an ECG ordered as part of routine clinical care, these estimates may be amplified by selection bias and do not directly represent the general population. Rather than serving as definitive evidence to support mass, population-level ECG screening, our findings should be considered hypothesis-generating and supportive of conducting a properly designed population-based study (with probability sampling) to determine the true community burden and to inform screening policy.