Presystolic wave as a predictor of interatrial block in patients with supraventricular tachycardia.

The identification of interatrial block (IAB) through electrocardiography (ECG) has been correlated with an elevated likelihood of developing atrial fibrillation (AF) and stroke. IAB is diagnosed by evaluating P-wave prolongation on a surface ECG. The presystolic wave (PSW) is an echocardiographic marker determined by pulse-wave examination of the aortic root during late diastole. As IAB and PSW share similar pathophysiological mechanisms, we speculated that PSW, as a component of the P wave, might be useful in predicting IAB. In the present study, we aimed to determine the relationship between PSW and IAB. Patients with pre-diagnosis of supraventricular tachycardia (SVT) on electrocardiography or rhythm Holter monitoring between January 2021 and December 2022 were included in the study. Surface 12-lead ECG and transthoracic echocardiography (TTE) were performed for the diagnosis of IAB and PSW. Patients were divided into two groups based on the presence of IAB, and PSW was compared between the groups. In total, 104 patients were enrolled in this study. IAB was diagnosed in 16 patients (15.3%) and PSW was detected in 33 patients (31.7%). The PSW was higher in the IAB ( +) group than in the IAB ( -) group (10 patients (71.4%) vs. 23 patients (32.4%), p = 0.008). PSW may be a useful tool for predicting IAB in patients with SVT. Further studies are needed to determine the clinical utility of PSW in the diagnosis and management of IAB.