Electrocardiographic Prognostic Marker in Pulmonary Arterial Hypertension: RS Time

Background: Pulmonary hypertension is a condition that involves the remodeling of the right ventricle. Ongoing remodeling is also associated with disease prognosis. During the restructuring process, complex changes such as hypertrophy and dilatation may also be reflected in electrocardiographic parameters. Objectives: Our study aimed to investigate the relationship between prognosis and electrocardiographic parameters in patients with pulmonary arterial hypertension. Methods: The study was designed retrospectively and included patients diagnosed with pulmonary arterial hypertension between 2010 and 2022. The patients were divided into two groups based on their survival outcome. Various parameters, including electrocardiographic, demographic, echocardiographic, catheter, and blood parameters, were compared between the two groups. A p-value of <0.05 was considered statistically significant. Results: In the multivariate Cox analyses, the parameters that were found to be independently associated with survival were the 6-minute walk test, mean pulmonary artery pressure, presence of pericardial effusion, and time between the beginning of the QRS and the peak of the S wave (RS time) (p<0.05 for each). Of all the parameters, RS time demonstrated the best diagnostic performance (AUC:0.832). In the survival analysis, a significant correlation was found between RS time and survival when using a cut-off value of 59.5 ms (HR: 0.06 [0.02-0.17], p < 0.001). Conclusions: According to the results of our study, a longer RS time is associated with poor prognosis in patients with pulmonary arterial hypertension. We can obtain information about the course of the disease with a simple, non-invasive parameter.