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

Identifying prognostic variables associated with the probability of recurrent paroxysmalsupraventricular tachycardia (PSVT) would aid decision-making regarding disposition of the patients. Thisstudy aims to develop a clinical scoring system to predict PSVT recurrence after adenosine administration inthe emergency department (ED).

This retrospective cross-sectional study was conducted on patientswho were referred to the emergency department of Ramathibodi Hospital, a university-affiliated super-tertiarycare hospital in Bangkok, Thailand, with diagnosis of PSVT during a 10-year period from 01 January 2010 un-til 31 December 2020. The cases were divided into recurrent and non-recurrent PSVT based on the responseto standard treatment and the independent predictors of recurrence were studied using multivariable logisticregression 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 PSVTrecurrence 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 sinusrhythm (p = 0.022) and total dose of adenosine (p = 0.002). We developed a clinical prediction score of PSVT re-currence with an accuracy of 79.5%. A score of 0 (low risk), 1–2 (moderate risk), and > 2 (high risk) had a positivelikelihood ratio (LR+) of 0.31, 0.56 and 2.33, respectively.

It seems that, using the PSVT recurrencescore we could screen the high-risk patients for PSVT recurrence (score>2) who need to be observed for at least6-12 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.