Upgrades from Previous Cardiac Implantable Electronic Devices Compared to De Novo Cardiac Resynchronization Therapy Implantations: Results from CRT Survey-II in the Turkish Population

OBJECTIVE
Cardiac resynchronization therapy is the guideline-directed treatment option in selected heart failure with reduced left ventricular ejection fraction patients. Data regarding the contemporary clinical practice of cardiac resynchronization therapy in Turkey have been published recently. This sub-study aims to compare clinical and periprocedural characteristics between cardiac resynchronization therapy upgrade and de novo implantations.

METHODS
Turkish arm of the Cardiac Resynchronization Therapy Survey-II was conducted between October 1, 2015, and December 31, 2016, at 16 centers. All consecutive patients who underwent an upgrade to cardiac resynchronization therapy system (n=60) or de novo cardiac resynchronization therapy implantation (n=335) were eligible.

RESULTS
Distribution of age, gender, and heart failure etiology were similar in the 2 groups. Atrial fibrillation, valvular heart disease, and chronic kidney disease were more common in car- diac resynchronization therapy upgrade patients. Narrow intrinsic QRS duration and left ven- tricular ejection fraction being <25% were more common in cardiac resynchronization therapy upgrade patients. Successful first attempt rates were 100% and 98.8% in upgrade and de novo implantation groups. Rates of periprocedural complications were similar between the 2 groups (8.3% vs. 5.9%), but postprocedural adverse events during hospitalization were more common in cardiac resynchronization therapy upgrade patients (18.3% vs. 9.0%), with worsening heart failure being the most common reason. Prescription rates of angiotensin-converting enzyme inhibitors/angiotensin-II receptor blockers, mineralocorticoid receptor antagonists, and beta- blockers were >75% in both groups, and only beta-blockers were prescribed at rates of >90% in both groups.

CONCLUSION
Cardiac resynchronization therapy upgrades are performed with high procedural success rates and without excess periprocedural complication risk. Feared complications of cardiac resynchronization therapy upgrades due to the pre-existing device should not delay the procedure if indicated.