Objectives The purpose of this study was to estimate rates and identify predictors of inpatient complications and 30-day readmissions, as well as repeat hospitalization rates for arrhythmia ...recurrence following atrial fibrillation (AF) ablation. Background AF is the most common clinically significant arrhythmia and is associated with increased morbidity and mortality. Radiofrequency or cryotherapy ablation of AF is a relatively new treatment option, and data on post-procedural outcomes in large general populations are limited. Methods Using data from the California State Inpatient Database, we identified all adult patients who underwent their first AF ablation from 2005 to 2008. We used multivariable logistic regression to identify predictors of complications and/or 30-day readmissions and Kaplan-Meier analyses to estimate rates of all-cause and arrhythmia readmissions. Results Among 4,156 patients who underwent an initial AF ablation, 5% had periprocedural complications, most commonly vascular, and 9% were readmitted within 30 days. Older age, female, prior AF hospitalizations, and less hospital experience with AF ablation were associated with higher adjusted risk of complications and/or 30-day readmissions. The rate of all-cause hospitalization was 38.5% by 1 year. The rate of readmission for recurrent AF, atrial flutter, and/or repeat ablation was 21.7% by 1 year and 29.6% by 2 years. Conclusions Periprocedural complications occurred in 1 of 20 patients undergoing AF ablation, and all-cause and arrhythmia-related rehospitalizations were common. Older age, female sex, prior AF hospitalizations, and recent hospital procedure experience were associated with a higher risk of complications and/or 30-day readmission after AF ablation.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Abstract Background The effectiveness of beta-blockers for preventing cardiac events has been questioned for patients who have coronary heart disease (CHD) without a prior myocardial infarction (MI). ...Objectives The purpose of this study was to assess the association of beta-blockers with outcomes among patients with new-onset CHD. Methods We studied consecutive patients discharged after the first CHD event (acute coronary syndrome or coronary revascularization) between 2000 and 2008 in an integrated healthcare delivery system who did not use beta-blockers in the year before entry. We used time-varying Cox regression models to determine the hazard ratio (HR) associated with beta-blocker treatment and used treatment-by-covariate interaction tests (pint ) to determine whether the association differed for patients with or without a recent MI. Results A total of 26,793 patients were included, 19,843 of whom initiated beta-blocker treatment within 7 days of discharge from their initial CHD event. Over an average of 3.7 years of follow-up, 6,968 patients had an MI or died. Use of beta-blockers was associated with an adjusted HR for mortality of 0.90 (95% confidence limits CL: 0.84 to 0.96), and an adjusted HR for death or MI of 0.92 (CL: 0.87 to 0.97). The association between beta-blockers and outcomes differed significantly between patients with and without a recent MI (HR for death: 0.85 vs. 1.02, pint = 0.007; and HR for death or MI: 0.87 vs. 1.03, pint = 0.005). Conclusions Use of beta-blockers among patients with new-onset CHD was associated with a lower risk of cardiac events only among patients with a recent MI.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Objectives The goal of this study was to compare the economic outcomes of patients undergoing different noninvasive tests to evaluate suspected coronary artery disease (CAD). Background Evaluation of ...noninvasive tests is shifting to an assessment of their effect on clinical outcomes rather than on their diagnostic accuracy. Economic outcomes of testing are particularly important in light of rising medical care costs. Methods We used an observational registry of 1,703 patients who underwent coronary computed tomography angiography (CTA) (n = 590), positron emission tomography (PET) (n = 548), or single-photon emission computed tomography (SPECT) (n = 565) for diagnosis of suspected CAD at 1 of 41 centers. We followed patients for 2 years, and documented resource use, medical costs for CAD, and clinical outcomes. We used multivariable analysis and propensity score matching to control for differences in baseline characteristics. Results Two-year costs were highest after PET ($6,647, 95% confidence interval CI: $5,896 to $7,397), intermediate after CTA ($4,909, 95% CI: $4,378 to $5,440), and lowest after SPECT ($3,965, 95% CI: $3,520 to $4,411). After multivariable adjustment, CTA costs were 15% higher than SPECT (p < 0.01), and PET costs were 22% higher than SPECT (p < 0.0001). Two-year mortality was 0.7% after CTA, 1.6% after SPECT, and 5.5% after PET. The incremental cost-effectiveness ratio for CTA compared with SPECT was $11,700 per life-year added, but was uncertain, with higher costs and higher mortality in 13% of bootstrap replications. Patients undergoing PET had higher costs and higher mortality than patients undergoing SPECT in 98% of bootstrap replications. Conclusions Costs were significantly lower after using SPECT rather than CTA or PET in the evaluation of suspected coronary disease. SPECT was economically attractive compared with PET, whereas CTA was associated with higher costs and no significant difference in mortality compared with SPECT.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Objectives The aim of this study was to assess the pattern of the adoption of internal mammary artery (IMA) grafting in the United States, test its association with clinical outcomes, and assess ...whether its effectiveness differs in key clinical subgroups. Background The effect of IMA grafting on major clinical outcomes has never been tested in a large randomized trial, yet it is now a quality standard for coronary artery bypass graft (CABG) surgery. Methods We identified Medicare beneficiaries ≥66 years of age who underwent isolated multivessel CABG between 1988 and 2008, and we documented patterns of IMA use over time. We used a multivariable propensity score to match patients with and without an IMA and compared rates of death, myocardial infarction (MI), and repeat revascularization. We tested for variations in IMA effectiveness with treatment × covariate interaction tests. Results The IMA use in CABG rose slowly from 31% in 1988 to 91% in 2008, with persistent wide geographic variations. Among 60,896 propensity score-matched patients over a median 6.8-year follow-up, IMA use was associated with lower all-cause mortality (adjusted hazard ratio: 0.77, p < 0.001), lower death or MI (adjusted hazard ratio: 0.77, p < 0.001), and fewer repeat revascularizations over 5 years (8% vs. 9%, p < 0.001). The association between IMA use and lower mortality was significantly weaker (p ≤ 0.008) for older patients, women, and patients with diabetes or peripheral arterial disease. Conclusions Internal mammary artery grafting was adopted slowly and still shows substantial geographic variation. IMA use is associated with lower rates of death, MI, and repeat coronary revascularization.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Objectives This study sought to examine the effectiveness of clopidogrel in real-world, medically managed patients with unstable angina (UA) or non–ST-segment elevation myocardial infarction ...(NSTEMI). Background Although clinical trials have demonstrated the efficacy of clopidogrel to reduce cardiovascular (CV) morbidity and mortality in medically managed patients with UA or NSTEMI, the effectiveness of clopidogrel in actual clinical practice is less certain. Methods A retrospective cohort study was conducted of Kaiser Permanente Northern California members without known coronary artery disease or prior clopidogrel use who presented with UA or NSTEMI between 2003 and 2008 and were medically managed (i.e., no percutaneous coronary intervention or coronary artery bypass grafting during the index hospitalization or within 7 days post-discharge). Over 2 years of follow-up, we measured the association between clopidogrel use and all-cause mortality, hospital stay for MI, and a composite endpoint of death or MI using propensity-matched multivariable Cox analyses. Results We identified 16,365 patients with incident UA (35%) or NSTEMI (65%); 36% of these patients were prescribed clopidogrel within 7 days of discharge. In 8,562 propensity score–matched patients, clopidogrel users had lower rates of all-cause mortality (8.3% vs. 13.0%; p < 0.01; adjusted hazard ratio HR: 0.63; 95% confidence interval CI: 0.54 to 0.72) and the composite of death or MI (13.5% vs. 17.4%; p < 0.01; HR: 0.74, CI: 0.66 to 0.84), but not MI alone (6.7% vs. 7.2%; p = 0.30; HR: 0.93, CI: 0.78 to 1.11), compared with nonusers of clopidogrel. The association between clopidogrel use and the composite of death or MI was significant only among patients presenting with NSTEMI (HR: 0.67; CI: 0.59 to 0.76; pint < 0.01), not among those presenting with UA (HR: 1.25; CI: 0.94 to 1.67). Conclusions In a large, community-based cohort of patients who were medically managed after UA/NSTEMI, clopidogrel use was associated with a lower risk of death and MI, particularly among patients with NSTEMI.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Objectives We sought to compare long-term outcomes after coronary bypass surgery with and without an internal thoracic artery graft. Methods We analyzed clinical outcomes over a median follow-up of ...6.7 years among 3,087 patients who received coronary bypass surgery as participants in one of 8 clinical trials comparing surgical intervention with angioplasty. We used 2 statistical methods (covariate adjustment and propensity score matching) to adjust for the nonrandomized selection of internal thoracic artery grafts. Results Internal thoracic artery grafting was associated with lower mortality, with hazard ratios of 0.77 (confidence interval, 0.62–0.97; P = .02) for covariate adjustment and 0.77 (confidence interval, 0.57–1.05; P = .10) for propensity score matching. The composite end point of death or myocardial infarction was reduced to a similar extent, with hazard ratios of 0.83 (confidence interval, 0.69–1.00; P = .05) for covariate adjustment to 0.78 (confidence interval, 0.61–1.00; P = .05) for propensity score matching. There was a trend toward less angina at 1 year, with odds ratios of 0.81 (confidence interval, 0.61–1.09; P = .16) in the covariate-adjusted model and 0.81 (confidence interval, 0.55–1.19; P = .28) in the propensity score–adjusted model. Conclusions Use of an internal thoracic artery graft during coronary bypass surgery seems to improve long-term clinical outcomes.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Aldosterone receptor antagonists have been shown in randomized trials to reduce morbidity and mortality in adults with symptomatic systolic heart failure. We studied the effectiveness and safety of ...spironolactone in adults with newly diagnosed systolic heart failure in clinical practice. We identified all adults with newly diagnosed heart failure, left ventricular ejection fraction of <40%, and no previous spironolactone use from 2006 to 2008 in Kaiser Permanente Northern California. We excluded patients with baseline serum creatinine level of >2.5 mg/dl or a serum potassium level of >5.0 mEq/L. We used Cox regression with time-varying covariates to evaluate the independent association between spironolactone use and death, hospitalization, severe hyperkalemia, and acute kidney injury. Among 2,538 eligible patients with a median follow-up of 2.5 years, 521 patients (22%) initiated spironolactone, which was not associated with risk of hospitalization (adjusted hazard ratio 0.91, 95% confidence interval 0.77 to 1.08) or death (adjusted hazard ratio 0.93, confidence interval 0.60 to 1.44). Crude rates of severe hyperkalemia and acute kidney injury during spironolactone use were similar to that seen in clinical trials. Spironolactone was independently associated with a 3.5-fold increased risk of hyperkalemia but not with acute kidney injury. Within a diverse community-based cohort with incident systolic heart failure, use of spironolactone was not independently associated with risks of hospitalization or death. Our findings suggest that the benefits of spironolactone in clinical practice may be reduced compared with other guideline-recommended medications.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Background Persons with end-stage renal disease (ESRD) on hemodialysis carry an exceptionally high burden of cardiovascular disease. Angiotensin-converting enzyme inhibitors (ACEIs) are recommended ...for patients on dialysis, but there are few data regarding their effectiveness in ESRD. Methods We conducted a secondary analysis of results of the HEMO study, a randomized trial of dialysis dose and membrane flux in patients on maintenance hemodialysis. We focused on the nonrandomized exposure of ACEI use, using proportional hazards regression and a propensity score analysis. The primary outcome was all-cause mortality. Secondary outcomes examined in the present analysis were cardiovascular hospitalization, heart failure hospitalization, and the composite outcomes of death or cardiovascular hospitalization and death or heart failure hospitalization. Results In multivariable-adjusted analyses, there were no significant associations among ACEI use and mortality (hazard ratio 0.97, 95% CI 0.82-1.14), cardiovascular hospitalization, and either composite outcome. Angiotensin-converting enzyme inhibitor use was associated with a higher risk of heart failure hospitalization (hazard ratio 1.41, 95% CI 1.11-1.80). In the propensity score–matched cohort, ACEI use was not significantly associated with any outcomes, including heart failure hospitalization. Conclusions In a well-characterized cohort of patients on maintenance hemodialysis, ACEI use was not significantly associated with mortality or cardiovascular morbidity. The higher risk of heart failure hospitalization associated with ACEI use may not only reflect residual confounding but also highlights gaps in evidence when applying treatments proven effective in the general population to patients with ESRD. Our results underscore the need for definitive trials in ESRD to inform the treatment of cardiovascular disease.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Background Prognostic factors are usually evaluated by their statistical significance rather than by their clinical utility. Risk reclassification measures the extent to which a novel marker adds ...useful information to a prognostic model. The extent to which estimated glomerular filtration rate (eGFR) adds information about prognosis among patients with coronary heart disease is uncertain. Methods We studied patients in an integrated health care delivery system with newly diagnosed coronary heart disease. We developed a model of the risk of death over 2 years of follow-up and then added eGFR to the model and measured changes in C-index, net reclassification improvement, and integrated discrimination improvement. Results Almost half of the 31,533 study patients had reduced eGFR (<60 mL/min per 1.73 m2 ). Mortality was significantly higher among patients who had lower levels of eGFR, even after adjustment for baseline characteristics ( P < .0001). The addition of eGFR to the prognostic model increased the C-index from 0.837 to 0.843, the net reclassification improvement by 3.2% ( P < .0001), and integrated discrimination improvement by 1.3% ( P = .007). Conclusion Estimated glomerular filtration rate is an informative prognostic factor among patients with incident coronary heart disease, independent of other clinical characteristics.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK