Background: Atrial septal defect (ASD) is common in adults and may cause chronic right ventricular (RV) volume overload and remodeling. Electrocardiography (ECG) may serve as a screening adjunct to echocardiography. Objectives: To evaluate the association of the terminal D1S + D3R ECG pattern, defined as a terminal S wave in lead I plus a terminal R wave in lead III, with structural and hemodynamic right heart involvement in adult secundum ASD. Methods: A total of 161 adult patients with secundum ASD were retrospectively analyzed. Right heart involvement was assessed using pulmonary-to-systemic flow ratio (Qp/Qs) ≥ 1.5 and a right ventricular/left ventricular (RV/LV) ratio > 1. ECG parameters, including right bundle branch block (RBBB), right axis deviation, V1–V2 R-wave positivity, and terminal D1S + D3R, were evaluated by two blinded cardiologists, with final classifications determined by consensus. Multivariable Firth penalized logistic regression, correlation analyses, and receiver operating characteristic (ROC) analyses were performed. Results: In the multivariable Firth penalized logistic regression model, pulmonary artery pressure (PAP) and ASD diameter were independently associated with Qp/Qs ≥ 1.5, whereas the terminal D1S + D3R pattern was not. The terminal D1S + D3R pattern was independently associated with RV dilatation after adjustment for age, sex, PAP, and ASD diameter (odds ratio [OR]: 9.90, 95% confidence interval [CI]: 2.82–38.20, p < 0.001) and showed good discriminatory performance for RV dilatation (area under the curve [AUC]: 0.881, 95% CI: 0.831–0.932). Conclusions: In adults with secundum ASD, a positive terminal D1S + D3R ECG pattern is independently associated with RV dilatation and may serve as a practical adjunctive screening marker. However, it should not replace echocardiographic assessment.

Background: In heart failure with reduced ejection fraction (HFrEF), implantable cardioverter-defibrillators (ICDs) are used for the primary prevention of sudden cardiac death, yet many patients never receive appropriate therapy, and left ventricular ejection fraction (LVEF) alone poorly discriminates who will. We investigated whether a cumulative electrical risk score (ERS) derived from the surface electrocardiogram is associated with appropriate ICD therapy. Methods: In this single-center, retrospective study, 205 patients with HFrEF who underwent ICD implantation for primary prevention were classified according to whether they had received appropriate ICD therapy. A modified eight-parameter ERS was calculated from the baseline electrocardiogram. Associations were assessed using receiver operating characteristic (ROC) analysis and logistic regression. Results: The ERS showed moderate-to-good discrimination (AUC 0.795; p < 0.001); a cut-off of 3.5 yielded 91% sensitivity and 71.4% specificity. After adjustment for age, sex, LVEF, cardiomyopathy etiology, BNP and device duration, the ERS remained independently associated with appropriate ICD therapy (adjusted OR 2.189; 95% CI 1.246–3.845; p = 0.006). Conclusions: A cumulative electrical risk score from the standard electrocardiogram was independently associated with appropriate ICD therapy and may add risk information beyond LVEF. These retrospective findings warrant prospective, multicenter validation.