PR Interval in Hypertrophic Cardiomyopathy patients: an easy and worthy risk factor?

Abstract

PR interval in hypertrophic cardiomyopathy patients: an easy and worthy risk factor? Background: Hypertrophic cardiomyopathy (HCM) has atrial fibrillation (AF) as one of the most feared complications. Recently, the presence of 1st-grade atrioventricular block (FGAVB) or PR interval higher than 200 ms was independently associated with HCM-related death. Methods: From cohort of HCM patients (pts) of the university hospital center São João, from 2000 to 2023. we analyzed those in sinus rhythm at first appointment, seeking relationships of PR interval duration with different clinical and image variables and with the occurrence of events. When testing a hypothesis about continuous variables, nonparametric tests and chi-square test were used as appropriate. Multivariate regression modeling was used in order to find predictive factors of FGAVB. Statistical level of significance used was 5%. Results: A total of 97 pts was included - 58,8% men, mean age of 51±19 years; 14 patients (14,4%) from total population had PR > 200 ms. During median 4,3 (IQR 5,8) years of follow-up 35 cardiovascular events occurred. Presence of FGAVB was not associated with the occurrence of the composite of events (p=0.751). After multivariable analysis, we found association between PR duration and echo parameter E/e´ ratio (p = 0.039) (or =1.588). Conclusions: In our cohort of sinus rhythm HCM patients, FGAVB was present in minority of patients and was not associated with events. We found association between FGAVB and higher E/e ratio. Key words: HCM, AF, FGAVB