Adenosine and other interventions show variable success in adult paroxysmal supraventricular tachycardia patients.
This retrospective observational study assessed treatment responses in 427 adult patients with paroxysmal supraventricular tachycardia at King Hamad University Hospital in Bahrain. The analysis included pharmacologic and non-pharmacologic interventions such as adenosine, vagal maneuvers, cardioversion, and electrical cardioversion. Symptom presentation data indicated that palpitations were the most common symptom reported in this cohort.
Regarding adenosine efficacy, 80.8% of patients (177 of 219) achieved cardioversion with the first dose. Success rates decreased with additional doses, with 11.4% (25 of 219) responding to a second dose and 7.8% (17 of 219) responding to a third dose. Electrical cardioversion was required in 4.2% of the total population (18 of 427), while pacemaker implantation was documented in 0.7% (3 of 427) for co-existing conduction disease.
Subgroup analyses suggested that patients with structural heart disease and diabetes mellitus experienced reduced success with vagal maneuvers. Conversely, hypertension was associated with a favorable response. Patients with heart failure or ischemic heart disease demonstrated poor response across all management modalities. The study noted that sex-based and age-related response differences were descriptive and require multivariable validation. Kaplan–Meier analyses for the cardioversion subgroup (n = 18) were presented as exploratory and descriptive only. Safety data, including adverse events and tolerability, were not reported.