Characterising paroxysmal supraventricular tachycardia episodes by patient-perceived episode duration, symptoms, and severity: longitudinal patient-reported outcomes

Abstract

Abstract Background/Information Paroxysmal supraventricular tachycardia (PSVT) encompasses a range of heart rhythms that are often associated with clinical symptoms. The duration and symptoms a patient experiences during a PSVT episode are variable. The impact of episode duration and symptom type on a patient’s perceived severity of an episode of PSVT has not been well defined. Purpose To characterise the relationship between duration, symptom type, and patient-perceived episode severity in a longitudinal study of patient-reported outcomes in the US and UK. Methods The survey included patients >18 years of age with a self-reported diagnosis of PSVT, without a history of ablation. Surveys included a 30-minute baseline survey (Mar 2019), 5-minute weekly tracking surveys (Mar 2019 to Dec 2019), and a 15-minute closing survey (Dec 2019). Patients were asked during the baseline survey to rate the severity of their PSVT (mild/moderate/severe). Weekly episode surveys assessed patient-reported episode duration, symptoms, severity, and interventions. If multiple episodes occurred, characteristics of the most recent episode were assessed. Results Among 117,252 patients screened, 368 met the inclusion criteria and completed the baseline survey, while 247 patients in the final cohort met the quality control checks. Most patients were White (92%), female (70%), and from the US (80%) and had a mean age of 52 years. At baseline, 47% of patients described their PSVT as moderate severity, while 39% reported mild and 14% reported severe. Overall, 5277 longitudinal weekly surveys were completed, of which 48% captured a PSVT episode (n=2518). Median reported duration of an episode was 15 minutes, with severe episodes having numerically longer duration (71 minutes) than moderate (20 minutes) or mild (6 minutes) episodes. Among severe episodes, 57% lasted 1 hour or longer; only 9% of mild episodes lasted 1 hour or longer (Figure 1). Among all assessed episodes of PSVT, 89% had palpitations, 35% shortness of breath, 26% dizziness, and 17% chest pain; mean number of symptoms per episode was 3.1, while numerically more symptoms were reported with severe episodes (mean 6.0) than with moderate (mean 3.5) or mild (mean 2.1) episodes. Shortness of breath was more frequently reported with severe episodes (81%) than with moderate (43%) or mild (17%) episodes. Similar findings were seen with dizziness and chest pain (Figure 2). Overall, approximately half of the reported episodes during follow-up were classified as moderate severity (47%), followed by mild (44%) and severe (9%). Conclusions Episodes of PSVT of longer duration and/or accompanied by a greater number of symptoms are reported by patients to be more severe. However, heterogeneity of symptoms and episode duration is substantial within a given classification of PSVT severity. Additional studies are needed to better understand how the optimal treatment of patients with PSVT may vary by duration, symptoms, and severity.