Under-utilization of pacemaker therapy for sinus node dysfunction - Real world data from South Asia

Chronic symptomatic sinus node dysfunction (SND), the most common bradyarrhythmia, can be effectively managed by permanent cardiac pacing. Yet the care pathway and barriers to adoption of pacing therapy are not well understood - particularly in low volume implanting countries. The IMPROVE Brady study is a quality improvement initiative being conducted at centers in South Asia, Latin America, and Russia. We assessed the rates of SND diagnosis and pacemaker treatment for SND in the South Asia cohort.

The prospective study enrolled patients with heart rate of  ≤50 beats per minute presenting with symptoms including syncope, dizziness, and/or dyspnea from ten centers in India and Bangladesh. Patients were followed to identify the proportion diagnosed with SND and subsequently treated with pacemaker therapy.

A total of 508 patients meeting criteria were enrolled and followed on average for 8.3±8.0months. Patients were on average 58 years of age, 77% were male, and 91% had completed at least primary education. An SND diagnosis was made in 368 (72%) of patients, with the majority (80%) of diagnoses occurring within 1 month of enrollment. Of the patients with an SND diagnosis, 63 (17%) were treated with a pacemaker. Reasons for not receiving treatment were: subject refusal or deferred decision (45%), unaffordability (34%), physician determined - not-indicated (20%), and other (1%). Older age, female gender, history of hypertension, lower resting heart rate, and syncopal or pre-syncopal symptoms were associated with a higher probability of implant.

In a care pathway assessment for the diagnosis and treatment of symptomatic SND in South Asia only 1 in 6 patients received pacemaker indicated therapy, largely due to patient refusal and physician decision. Phase II of the study will be aimed to improve this treatment rate.