Permanent pacemaker use among patients with heart failure and preserved ejection fraction: Findings from the Acute Decompensated Heart Failure National Registry (ADHERE) National Registry.

BACKGROUND: Heart failure with preserved ejection fraction may be associated with chronotropic incompetence, but little is known about the incidence and prevalence of permanent pacemaker use in this population or factors associated with its use. METHODS: We analyzed patients with heart failure with preserved ejection fraction (ie, left ventricular ejection fraction greater than 40%) from the ADHERE registry (2001-2006) linked with Medicare claims. We described the use of both prevalent and incident permanent pacemakers in heart failure with preserved ejection fraction and determined factors associated with pacemaker use with logistic regression models. RESULTS: Among 13,881 patients with heart failure with preserved ejection fraction, 3136 (22.6%) had a permanent pacemaker, and of these patients, 636 had a permanent pacemaker implanted during hospitalization. Permanent pacemaker use was more common among older patients (81 vs 79 years; P < .001), men (38% vs 34%; P < .001), patients with atrial fibrillation (58% vs 36%; P < .001), and patients with wider QRS duration (140 ms vs 94 ms; P < .001). Rates of digoxin, aldosterone antagonist, and loop diuretic use were slightly higher in patients with a permanent pacemaker compared with patients with no permanent pacemaker. Factors associated with both prevalent and incident pacemaker use included age, fast or slow heart rate, atrial fibrillation, and lower body mass index. CONCLUSIONS: Use of permanent pacemakers is relatively common among patients with heart failure with preserved ejection fraction.

Outcomes According to Cardiac Catheterization Referral and Clopidogrel Use Among Medicare Patients With Non-ST-Segment Elevation Myocardial Infarction Discharged Without In-hospital Revascularization.

BACKGROUND: While use of P2Y12 receptor inhibitor is recommended by guidelines, few studies have examined its effectiveness among older non-ST-segment elevation myocardial infarction patients who did not undergo coronary revascularization. METHODS AND RESULTS: We included unrevascularized non-ST-segment elevation myocardial infarction patients ≥65 years discharged home from 463 ACTION Registry-GWTG hospitals from 2007 to 2010. Rates of discharge clopidogrel use were described for patients with no angiography, angiography without obstructive coronary artery disease (CAD; ≥50% stenosis in ≥1 vessel), and angiography with obstructive CAD. Two-year outcomes were ascertained from linked Medicare data and included composite major adverse cardiac events (defined as all-cause death, myocardial infarction readmission, or revascularization), and individual components. Outcomes associated with clopidogrel use were adjusted using inverse probability-weighted propensity modeling. Of 14 154 unrevascularized patients, 54.7% (n=7745) did not undergo angiography, 10.6% (n=1494) had angiography without CAD, and 34.7% (n=4915) had angiography with CAD. Discharge clopidogrel was prescribed for 42.2% of all unrevascularized patients: 37.8% without angiography, 34.1% without obstructive CAD at angiography, and 51.6% with obstructive CAD at angiography. Discharge clopidogrel use was not associated with major adverse cardiac events in any group: without angiography (adjusted hazard ratio [95% CI]: 0.99 [0.93-1.06]), angiography without CAD (1.04 [0.74-1.47]), and angiography with CAD (1.12 [1.00-1.25], Pinteraction=0.20). CONCLUSIONS: We found no association between discharge clopidogrel use and long-term risk of major adverse cardiac events among older, unrevascularized non-ST-segment elevation myocardial infarction patients. Clopidogrel use in this population requires further prospective evaluation.

Impact of global geographic region on time in therapeutic range on warfarin anticoagulant therapy: data from the ROCKET AF clinical trial.

BACKGROUND: Vitamin K antagonist (VKA) therapy remains the most common method of stroke prevention in patients with atrial fibrillation. Time in therapeutic range (TTR) is a widely cited measure of the quality of VKA therapy. We sought to identify factors associated with TTR in a large, international clinical trial. METHODS AND RESULTS: TTR (international normalized ratio [INR] 2.0 to 3.0) was determined using standard linear interpolation in patients randomized to warfarin in the ROCKET AF trial. Factors associated with TTR at the individual patient level (i-TTR) were determined via multivariable linear regression. Among 6983 patients taking warfarin, recruited from 45 countries grouped into 7 regions, the mean i-TTR was 55.2% (SD 21.3%) and the median i-TTR was 57.9% (interquartile range 43.0% to 70.6%). The mean time with INR <2 was 29.1% and the mean time with an INR >3 was 15.7%. While multiple clinical features were associated with i-TTR, dominant determinants were previous warfarin use (mean i-TTR of 61.1% for warfarin-experienced versus 47.4% in VKA-naïve patients) and geographic region where patients were managed (mean i-TTR varied from 64.1% to 35.9%). These effects persisted in multivariable analysis. Regions with the lowest i-TTRs had INR distributions shifted toward lower INR values and had longer inter-INR test intervals. CONCLUSIONS: Independent of patient clinical features, the regional location of medical care is a dominant determinant of variation in i-TTR in global studies of warfarin. Regional differences in mean i-TTR are heavily influenced by subtherapeutic INR values and are associated with reduced frequency of INR testing. CLINICAL TRIAL REGISTRATION: URL: ClinicalTrials.gov. Unique identifier: NCT00403767.