Cardiac Device Complication Rate Holds at 5.5% in Indian Tertiary Care Study

Cardiac pacemakers, implantable cardioverter-defibrillators, and cardiac resynchronization therapy devices collectively save and extend millions of lives each year. They also carry procedural and post-implant risks: infection, lead displacement, device malfunction. How those risks compare across different healthcare settings - and whether they differ between male and female patients - are questions that national-level data alone cannot answer. Local, prospective studies from specific care environments are needed.

A team at a tertiary care center in India enrolled 183 patients receiving cardiac implantable electronic devices between February 2023 and January 2024 and tracked them for two years. Their findings, published in the journal Cureus, document a 5.5% adverse event rate that aligns closely with both international registries and existing Indian data - and found no statistically significant differences in complication rates between men and women.

Who Got What Device

Of the 183 patients, 95% received conventional cardiac pacemakers, 3% cardiac resynchronization therapy (CRT) devices, and 2% implantable cardioverter-defibrillators (ICDs). The patient group was 58% male with a mean age of 63 years. The most common indication for device implantation was atrioventricular block, followed by sick sinus syndrome - both arrhythmic conditions in which the heart's electrical conduction system fails to maintain an adequate rhythm.

The heavy preponderance of pacemakers over ICDs and CRT devices reflects the device mix typical of Indian tertiary centers, where the complexity of cases and resource availability differ from high-income country referral centers where ICDs and CRT make up a larger share of implants.

Ten Adverse Events Over Two Years

Ten patients experienced device-related adverse events during the two-year follow-up period, for an overall rate of 5.5%. Device infection was the most common complication, occurring in seven patients (3.8% of the total). Lead dislodgement - where the electrode shifts from its intended position in the heart - affected two patients (1.09%). One patient (0.54%) experienced generator dysfunction.

The Kaplan-Meier survival analysis revealed that adverse events clustered in the first six months after implantation, followed by a stable period with minimal new events. This early-risk pattern matches what is seen internationally: the post-procedural wound healing phase and initial lead maturation period carry the highest risk, after which complication rates fall substantially.

No statistically significant differences in adverse event rates appeared when patients were stratified by sex, age group, indication for implantation, or comorbidity burden (P greater than 0.05 for all comparisons). A Cox proportional hazards model tested multiple potential predictors of adverse events and found none reached significance.

Are These Results Reassuring?

A 5.5% adverse event rate over two years sits within the range reported by both large international device registries and earlier Indian studies. The European Heart Rhythm Association registry, for comparison, reports pacemaker complication rates in the 4 to 7% range depending on patient population and device type. The alignment suggests that outcomes at this Indian center are not an outlier - a meaningful finding for healthcare quality assessment in a setting where device implantation volumes are growing rapidly.

The finding of no sex-based differences is notable given that women are historically underrepresented in cardiac device trials and sometimes experience different outcomes than men in large registry analyses, partly because of anatomical differences in vascular access and lead positioning. The absence of a significant difference here may reflect genuine equivalence in outcomes, or may reflect the study's limited statistical power to detect modest sex-based effects.

Important Limitations

The study's authors are direct about its constraints. The 183-patient sample is modest for drawing firm statistical conclusions about subgroup comparisons. The two-year follow-up, while adequate for capturing early complications, does not address later device-related issues such as lead failure from long-term fatigue or battery depletion management. The single-center design limits generalizability to other Indian institutions with different patient mixes, surgical volumes, and post-procedural care protocols.

The observation that adverse events were most common in patients older than 50 years warrants attention, even though it did not reach statistical significance in the Cox model. With a larger sample, age might emerge as a meaningful predictor - and since the vast majority of device recipients are older adults, this is a clinically relevant question.

Adverse events were documented and reported to the Indian Pharmacopoeia Commission as part of the country's pharmacovigilance framework, contributing to national safety surveillance data. That regulatory reporting function, independent of the study's scientific conclusions, represents a practical value of the prospective design.