A Clinical Score for Predicting the Paroxysmal Supraventricular Tachycardia's Recurrence Risk; a Retrospective Cross-sectional Study.

Abstract

Identifying prognostic variables associated with the probability of recurrent paroxysmal supraventricular tachycardia (PSVT) would aid decision-making regarding disposition of the patients. This study aims to develop a clinical scoring system to predict PSVT recurrence after adenosine administration in the emergency department (ED). This retrospective cross-sectional study was conducted on patients who were referred to the emergency department of Ramathibodi Hospital, a university-affiliated super-tertiary care hospital in Bangkok, Thailand, with diagnosis of PSVT during a 10-year period from 01 January 2010 until 31 December 2020. The cases were divided into recurrent and non-recurrent PSVT based on the response to standard treatment and the independent predictors of recurrence were studied using multivariable logistic regression analysis. 264 patients were diagnosed with PSVT and successfully converted by adenosine. 24 (9.1%) had recurrent PSVT, and 240 (90.9%) had no recurrent PSVT in the same ED visit. The risk of PSVT recurrence in ED corresponded with the history of hypertension (p = 0.059), valvular heart disease (p = 0.052), heart rate ≥ 100 (p = 0.012), and systolic blood pressure < 100 after electrocardiogram (ECG) converted to sinus rhythm (p = 0.022) and total dose of adenosine (p = 0.002). We developed a clinical prediction score of PSVT recurrence with an accuracy of 79.5%. A score of 0 (low risk), 1-2 (moderate risk), and > 2 (high risk) had a positive likelihood ratio (LR+) of 0.31, 0.56 and 2.33, respectively. It seems that, using the PSVT recurrence score we could screen the high-risk patients for PSVT recurrence (score>2) who need to be observed for at least 6-12 hours and receive cardiologist consultation in ED. In addition, the moderate and low-risk group (score 0-2) need to be observed for 1 hour and can be discharged from ED.