Quantitative Inferior T‐Wave Inversion as a Marker of High Pulmonary Vascular Resistance and All‐Cause Mortality in Patients Evaluated for Pulmonary Hypertension

ABSTRACT Right heart catheterization defines pulmonary hypertension (PH) hemodynamics, but simple markers of pulmonary vascular load remain useful. Inferior‐lead T‐wave inversion (TWI) is seen in right ventricular pressure overload; its association with pulmonary vascular resistance (PVR) and prognosis is uncertain. We retrospectively studied a cohort of 98 patients who underwent electrocardiography (ECG), echocardiography, and right heart catheterization within 48 h from 2021 to 2023. Inferior TWI amplitudes in leads II, III, and aVF were measured as absolute values and summed. Associations with PVR, performance for PVR > 5 Wood units, and all‐cause mortality were evaluated. Twenty‐five patients (26%) had PVR > 5 Wood units. The inferior TWI sum correlated with PVR ( ρ = 0.326, p = 0.001) and discriminated PVR > 5 Wood units better than conventional ECG markers (area under the curve, 0.78). A cutoff > 0.10 mV yielded 72% sensitivity, 84% specificity, and an odds ratio of 13.1 (95% confidence interval [CI], 4.5–38.1; p < 0.001). During a median follow‐up of 731 days, 19 patients died. Inferior TWI sum > 0.15 mV was associated with higher mortality (log‐rank p = 0.015) and remained associated after adjustment for age and log 2 N‐terminal pro‐B‐type natriuretic peptide (NT‐proBNP) (hazard ratio, 3.83; 95% CI, 1.48–9.90; p = 0.007). Adding this ECG marker increased the global chi‐square from 12.0 to 19.3. Quantitative inferior‐lead TWI was associated with high PVR and all‐cause mortality in patients evaluated for PH. It may complement non‐invasive assessment and right heart catheterization but requires external validation.