Use of Cardiac Resynchronization Therapy Defibrillator in US Hospitals.

This population-based study describes use of the cardiac resynchronization therapy defibrillator when the 2012 American College of Cardiology/American Heart Association/Heart Rhythm Society guidelines for device-based therapy of cardiac rhythm abnormalities were revised. Key PointsQuestionHas use of cardiac resynchronization therapy defibrillator (CRT-D) changed with the American College of Cardiology/American Heart Association/Heart Rhythm Society guideline update in 2012? FindingsIn this study of more than 85000 new CRT-D implants from 2012 to 2015 through the National Cardiovascular Data Registry for implantable cardioverter-defibrillators, there was an increase in guideline-concordant implantation during the period. The major fraction of guideline-discordant implants were clustered at a minority of hospitals. MeaningNationally, an increase in guideline-concordant CRT-D implantation was noted, suggesting improved patient selection in those most likely to benefit from this therapy; continued, focused opportunities for improvement in the use of CRT-D may be useful in addressing guideline-discordant implants at a minority of hospitals. ImportanceCardiac resynchronization therapy (CRT) provides significant reduction in morbidity and mortality in select patients with left ventricular systolic dysfunction and specific parameters of electrocardiographic evidence of dyssynchrony. Relative to the 2012 American College of Cardiology/American Heart Association/Heart Rhythm Society guideline update for patient selection, little is known about the contemporary use of CRT in the United States. ObjectiveTo describe the use of CRT defibrillator (CRT-D) in the period around guideline revision. Design, Setting, and ParticipantsAll patients undergoing new CRT-D implantations in the National Cardiovascular Data Registry for implantable cardioverter-defibrillators from January 1, 2012, to December 31, 2015, at 1710 participating hospitals were identified for this population-based study. Rates of CRT-D implantation that were concordant and discordant with the 2012 American College of Cardiology/American Heart Association/Heart Rhythm Society update of the 2008 guidelines for device-based therapy were determined. Analysis began in January 2012. Main Outcomes and MeasuresIncrease in guideline-concordant CRT-D implantation. ResultsAmong 135253 patients undergoing initial CRT-D implantation, 88923 were included in the study cohort, of which 73859 implants (83.1%) were guideline concordant. The proportion of guideline-concordant devices increased from 81.2% (16710 of 20481) in 2012 to 84.2% (20515 of 24356) in 2015 (P for trend<.001). Significant clustering was noted with 33% (565 of 1710) of hospitals accounting for greater than 70% (10 545 of 15 065) of guideline-discordant CRT-D implants. Conduction abnormalities, in particular, underlying right bundle branch block (3597 [23.9%] vs 7425 [10.1%]; P<.001) and nonspecific intraventricular conduction delay (3341 [22.2%] vs 4769 [6.5%]; P<.001) were more common in those who received guideline-discordant devices. Conclusions and RelevanceRates of guideline-concordant CRT-D implantation increased during the study. The major fraction of guideline-discordant implants were clustered at a minority of hospitals. Conduction abnormalities, particularly non-left bundle branch block and nonspecific intraventricular conduction delay, correlated with guideline-discordant implants indicating continued opportunity for dissemination and understanding of guideline updates.