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

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 log2 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.