The evolution of electrocardiographic signs of right ventricular overload after balloon pulmonary angioplasty in chronic thromboembolic pulmonary hypertension.

Balloon pulmonary angioplasty (BPA) is a treatment option for a patient with chronic thromboembolic pulmonary hypertension. We aimed to investigate the evolution of electrocardiographic (ECG) markers of right ventricular hypertrophy (RVH) after BPA. Standard 12‑lead ECG was performed in 41 patients with chronic thromboembolic pulmonary hypertension before the first BPA and after completion of treatment. In the whole study group, the percentage change in the pulmonary vascular resistance (PVR) after BPA correlated with the percentage change in the values of the following ECG parameters (P <0.05): axis of the QRS (rho = 0.530) and T wave (rho = 0.372); P wave in leads II (rho = 0.340) and III (rho = 0.430); S wave in lead V5 (rho = 0.634); R/S ratio in lead V5 (rho = -0.636); S wave in lead V6 (rho = 0.508); S wave in lead I (rho = 0.496). Then, the group was divided into 2 subgroups: group A, defined as a drop in PVR greater than the median value (49%) for the whole study population; and group B, defined as a drop in PVR below the median value. In group A, the following parameters changed after BPA: T‑wave axis (P <0.001), P wave in lead II (P <0.001), S wave in lead V5 (P <0.001), R/S ratio in lead V5 (P <0.001). In group B, despite some hemodynamic and functional improvement, there were no differences in ECG mark ers of RVH after BPA. An improvement in RVH parameters can be observed on ECG after a hemodynamically effective BPA.