Reoperation is not uncommon in the years after getting an implantable cardioverter defibrillator (ICD) — whether for complications or battery replacement, a registry study showed.
After adjustment for the competing risk of mortality, there were 6.1 ICD-related complications per 100 patient-years requiring rehospitalization. These complications — mainly infection and device malfunction — required 2.61 reoperations per 100 patient-years during the median 2.7 years of follow-up.
In addition, there were 3.9 reoperations per 100 patient-years for reasons beyond ICD complications, such as device upgrades and generator replacements, Isuru Ranasinghe, MBChB, MMed, PhD, of Queen Elizabeth Hospital in Adelaide, Australia, and colleagues reported in the Annals of Internal Medicine.
“Patients have a high rate of device-related complications and reoperation for other causes after ICD implantation. Risks of ICD implantation and strategies to reduce them should be actively considered before implantation,” the researchers wrote.
ICD-related complications were most likely with the following:
- Age 65 to 69 (hazard ratio [HR] 1.55 versus over 85, 95% confidence interval [CI] 1.43-1.69)
- Cardiac resynchronization therapy (CRT) devices versus single-chamber alternatives (HR 1.38, 95% CI 1.31-1.45)
- Female sex (HR 1.16, 95% CI 1.12-1.21)
- Black race (HR 1.14, 95% CI 1.05-1.23)
To reduce the long-term risk of ICD reoperation, Ranasinghe’s group suggested minimizing ICD implantation in patients with a marginal indication and, when opting for the device placement, choosing a single-chamber device unless there is a strong indication for a more complex device.
Sean Pokorney, MD, of Duke University School of Medicine in Durham, N.C., agreed.
“Clinicians need to continue to be thoughtful about patient selection, as well as the type of device that is implanted, particularly when deciding between a single chamber and dual chamber device,” he told MedPage Today.
The authors also noted that “assessment of the current of injury at lead implantation may reduce lead complications, and avoiding bridging anticoagulation may minimize hematoma formation. Furthermore, optimizing device settings may also reduce the risk for nonfatal events.
“For example, antitachycardia pacing may diminish the risk for inappropriate shocks, and lowering the rate threshold for right ventricular pacing may maximize battery life, which would delay the need for generator replacement.”
“Even risks from expected reoperations, such as generator replacement for battery depletion, are modiﬁable because battery life varies among manufacturers. Choosing a generator with a longer battery life may substantially delay the need for reoperation for generator replacement,” they wrote.
The observational study included 114,484 patients who received their first ICD between 2006 and 2010. Data were submitted to the National Cardiovascular Data Registry ICD registry from 1,437 participating U.S. hospitals and linked to Medicare fee-for-service claims.
With 12.6 deaths per 100 patient-years, there was a 35% mortality rate during follow-up.
Pokorney, who was not involved in the study, agreed that it is “important to understand the risks associated with device implantation,” although he expressed some caution in interpreting the study.
“The highest risk patients for complications were the CRT-D patients. The authors point out that two-thirds of ICD patients may never receive an appropriate therapy, but CRT patients have symptom improvement and/or reductions of heart failure hospitalizations in approximately two-thirds of cases. These patients are at higher risk for post-procedure complications, but they stand to have meaningful morbidity and mortality benefit, shifting the risk versus benefit equation,” he emphasized.
“Unfortunately, there are limited details available on the complications, since this was claims data based research, and it remains unclear how how many of these complications were modifiable versus unmodifiable complications related to the underlying health of a patient population with multiple comorbidities.
“Another important point is that the authors do not evaluate complications based on the volume of device implantations by provider or by hospital, and device implantation volume may play an important role in the rates of complications,” Pokorney commented.
Ranasinghe reported grants from the American College of Cardiology Foundation, the National Health and Medical Research Council of Australia, and the National Heart Foundation of Australia during the conduct of the study.
Pokorney disclosed receiving research grant support from Boston Scientific and consultant support from Medtronic and Boston Scientific.
Annals of Internal Medicine
Ranasinghe I, et al “Long-term risk for device-related complication and reoperations after implantable cardioverter-defibrilator implantation” Ann Intern Med 2016; DOI:10.7326/M15-2732.