Prevalence of guideline-directed medical therapy among patients receiving cardiac resynchronization therapy defibrillator implantation in the National Cardiovascular Data Registry during the years 2006 to 2008.

Cardiac resynchronization therapy (CRT) reduces morbidity and mortality among selected patients with left ventricular systolic dysfunction and severe heart failure symptoms despite guideline-directed medical therapy (GDMT). Contemporaneous guidelines provided clear recommendations regarding selection of patients for CRT, including that all patients should first receive GDMT with ß blockers and renin-angiotensin axis antagonists. Prevalence of GDMT among real-world patients receiving CRT defibrillators (CRT-D) has not been well studied. We identified 45,392 patients in the National Cardiovascular Data Registry Implantable Cardioverter-Defibrillator Registry who underwent first CRT-D implantation for primary prevention of sudden death from January 2006 to June 2008. We calculated the proportion of patients with contemporaneous class I guideline indications for CRT-D, the proportion receiving GDMT for heart failure, and the proportion receiving GDMT who had class I guideline indications for CRT-D. Among patients without contraindications, 87% were prescribed ß blockers, 78% an angiotensin-converting enzyme inhibitor or an angiotensin II receptor inhibitor, and 70% both a ß blocker and an angiotensin-converting enzyme or angiotensin II receptor inhibitor at discharge. Finally, 50% of patients met class I guideline indications and were prescribed GDMT at discharge; 9% neither met class I indications nor were prescribed GDMT at discharge. The major limitation of this study is the lack of dosage information in the Implantable Cardioverter-Defibrillator Registry and lack of prescribing information at times other than discharge. In conclusion, many patients receiving CRT-D are not receiving GDMT at discharge. Ensuring that all patients receiving CRT-D are also receiving GDMT appears to be a quality improvement target.

Treatment of obstructive sleep apnea reduces the risk of atrial fibrillation recurrence after catheter ablation.

OBJECTIVES: The aim of this study was to examine the effect of continuous positive airway pressure (CPAP) therapy on atrial fibrillation (AF) recurrence in patients with obstructive sleep apnea (OSA) undergoing pulmonary vein isolation (PVI). BACKGROUND: OSA is a predictor of AF recurrence following PVI. However, the impact of CPAP therapy on PVI outcome in patients with OSA is poorly known. METHODS: Among 426 patients who underwent PVI between 2007 and 2010, 62 patients had a polysomnography-confirmed diagnosis of OSA. While 32 patients were "CPAP users" the remaining 30 patients were "CPAP nonusers." The recurrence of any atrial tachyarrhythmia, use of antiarrhythmic drugs, and need for repeat ablations were compared between the groups during a follow-up period of 12 months. Additionally, the outcome of patients with OSA was compared to a group of patients from the same PVI cohort without OSA. RESULTS: CPAP therapy resulted in higher AF-free survival rate (71.9% vs. 36.7%; p = 0.01) and AF-free survival off antiarrhythmic drugs or repeat ablation following PVI (65.6% vs. 33.3%; p = 0.02). AF recurrence rate of CPAP-treated patients was similar to a group of patients without OSA (HR: 0.7, p = 0.46). AF recurrence following PVI in CPAP nonuser patients was significantly higher (HR: 2.4, p < 0.02) and similar to that of OSA patients managed medically without ablation (HR: 2.1, p = 0.68). CONCLUSIONS: CPAP is an important therapy in OSA patients undergoing PVI that improves arrhythmia free survival. PVI offers limited value to OSA patients not treated with CPAP.

Prevalence and predictors of off-label use of cardiac resynchronization therapy in patients enrolled in the National Cardiovascular Data Registry Implantable Cardiac-Defibrillator Registry.

OBJECTIVES: The purpose of the study was to define the extent and nature of cardiac resynchronization therapy (CRT) device usage outside consensus guidelines using national data. BACKGROUND: Recent literature has shown that the application of CRT in clinical practice frequently does not adhere to evidence-based consensus guidelines. Factors underlying these practices have not been fully explored. METHODS: From the National Cardiovascular Data Registry's Implantable Cardiac-Defibrillator Registry, we defined a cohort of 45,392 cardiac resynchronization therapy-defibrillator (CRT-D) implants between January 2006 and June 2008 with a primary prevention indication. We defined "off-label" implants as those in which the ejection fraction was >35%, the New York Heart Association functional class was below III, or the QRS interval duration was <120 ms in the absence of a documented need for ventricular pacing. The relationships between patient, implanting physician, and hospital characteristics with off-label use were explored with multivariable hierarchical logistic regression models. RESULTS: Overall, 23.7% of devices were placed without meeting all 3 implant criteria, most often due to New York Heart Association functional class below III (13.1% of implants) or QRS interval duration <120 ms (12.0%). Atrial fibrillation/flutter, previous percutaneous coronary intervention, and the performance of an electrophysiology study before implant were independently associated with increased odds of off-label use, whereas diabetes mellitus, increasing age, and female sex were associated with decreased odds. Physician training and insurance payer were weakly associated with the likelihood of off-label use. CONCLUSIONS: Nearly 1 in 4 patients receiving CRT devices in the study time frame did not meet guideline-based indications. Given the evolving evidence base supporting the use of CRT, these practices require careful scrutiny.