Downstream clinical implications of abnormal myocardial perfusion single-photon emission computed tomography based on appropriate use criteria.

BACKGROUND: Appropriate use criteria (AUC) for single-photon emission computed tomography myocardial perfusion images (SPECT-MPI) were developed to address the growth of cardiac imaging studies. However, these criteria have not been vigorously validated. We sought to determine the rate of abnormal stress SPECT-MPI studies and subsequent revascularization procedures as categorized by AUC. METHODS: We retrospectively examined 280 patients who underwent stress SPECT-MPI and categorized these studies as appropriate, inappropriate, or uncertain based on AUC. Data regarding subsequent angiography and revascularization within 6 months after stress SPECT-MPI were collected from the electronic medical record. RESULTS: 280 patients met the inclusion criteria (mean age 67.3 ± 11.4 years, 36 % female). When categorized by AUC, 62.9 % (N = 176) of stress SPECT-MPI were considered appropriate, 13.6 % (N = 38) uncertain, and 23.6 % (N = 66) inappropriate. Appropriate stress SPECT-MPI studies were more likely to have intermediate or high risk results than uncertain or inappropriate studies [40 % (N = 71) vs. 21 % (N = 8) and 18 % (N = 12), respectively; P = 0.008)]. Appropriate studies were associated with an increased rate of coronary angiography [14 % (N = 25)] compared to the uncertain (0 %) and inappropriate [3 % (N = 2)] studies (P = 0.003). There was also an increased rate of revascularization after appropriate studies [9 % (N = 16)] compared to the uncertain (0 %) and inappropriate (0 %) studies (P = 0.006). CONCLUSIONS: Appropriate stress SPECT-MPI studies are more likely to result in abnormal results requiring subsequent revascularization compared to inappropriate and uncertain stress studies. Inappropriate and uncertain stress SPECT-MPI did not lead to subsequent revascularization.

Implantable cardioverter defibrillators in patients with valvular cardiomyopathy.

BACKGROUND: Implantable cardioverter-defibrillators (ICDs) are beneficial for preventing sudden cardiac death (SCD) in patients with previous SCD or left ventricular dysfunction. OBJECTIVE: The objective was to investigate the outcomes of ICD implantation in patients who have surgery for valvular cardiomyopathy (VCM). METHODS: We identified patients with VCM who had ICD implantation after valve surgery. Age- and sex-matched patients who received an ICD for ischemic cardiomyopathy (ICM) and dilated cardiomyopathy (DCM) served as controls. Patients with VCM who had valve surgery but did not receive an ICD served as an additional control group. We compared mortality and appropriate ICD discharges between the study group and control groups. RESULTS: Mean (SD) age (31 patients with VCM with ICD, 30 with ICM, 26 with DCM, and 62 patients with VCM without ICD) was 60 (15) years, 73% were men. Ejection fraction at ICD implantation was 34%, 26%, and 23% for the VCM with ICD, ICM, and DCM groups, respectively (P = 0.03). After a median follow-up of 4.1 years, survival was not significantly different among ICD groups (P = 0.06). The annual appropriate shock rate was 5%, 10%, and 4% for the VCM with ICD, ICM, and DCM groups, respectively (P = 0.71). Compared to VCM without ICD, patients with VCM and ICD had comparable survival (P = 0.82) despite a reduced LVEF following valve surgery. CONCLUSION: Patients with VCM who undergo ICD implantation for SCD prevention have similar appropriate ICD discharge rates and mortality as do those with ICM and DCM. These data are hypothesis generating and deserve confirmation with large-scale prospective studies.

Association of novel risk factors with the ankle brachial index in African American and non-Hispanic white populations.

OBJECTIVES: To investigate whether novel risk factors, including C-reactive protein (CRP), fibrinogen, lipoprotein(a) [Lp(a)], and homocysteine levels, are associated with the ankle brachial index (ABI) in African American and non-Hispanic white populations and whether novel risk factors account for ethnic differences in peripheral arterial disease (PAD). PARTICIPANTS AND METHODS: Between December 2000 and October 2004, original participants in the Genetic Epidemiology Network of Arteriopathy study returned for a second study visit to undergo measurement of risk factors and ABI. The CRP, Lp(a), and homocysteine levels were log transformed to reduce skewness. Multivariable regression analyses were used to assess whether a novel risk factor was associated with ABI after adjustment for conventional risk factors and whether ethnicity was associated with PAD (ABI,

Factors associated with 30-day readmission rates after percutaneous coronary intervention.

BACKGROUND: Thirty-day readmission rates have become a publicly reported quality performance measure for congestive heart failure, acute myocardial infarction, and percutaneous coronary intervention (PCI). However, little is known regarding the factors associated with 30-day readmission after PCI. METHODS: To assess the demographic, clinical, and procedural factors associated with 30-day readmission rates after PCI, we identified 15, 498 PCI hospitalizations (elective or for acute coronary syndromes) from January 1998 through June 2008 at Saint Marys Hospital, Rochester, Minnesota. All were included in this analysis. Multivariate logistic regression models were used to estimate the adjusted association between demographic, clinical, and procedural variables and 30-day readmission. The association between 30-day readmission and 1-year mortality was estimated using Cox proportional hazards models with readmission as a time-dependent covariate and by using landmark analysis. The main outcome measures were all-cause 30-day readmission to any hospital following PCI and 1-year mortality. RESULTS: Overall, 9.4% of PCIs (n = 1459) were readmitted, and 0.68% of PCIs (n = 106) resulted in death within 30 days after discharge. After multivariate analysis, female sex, Medicare insurance, having less than a high school education, unstable angina, cerebrovascular accident or transient ischemic attack, moderate to severe renal disease, chronic obstructive pulmonary disease, peptic ulcer disease, metastatic cancer, and a length of stay of more than 3 days were associated with an increased risk of 30-day readmission after PCI. Thirty-day readmission after PCI was associated with a higher risk of 1-year mortality (adjusted hazard ratio, 1.38; 95% CI, 1.08-1.75; P = .009). CONCLUSIONS: Nearly 1 in 10 patients undergoing PCI were readmitted within 30 days. Thirty-day readmission after PCI was associated with a higher risk of 1-year mortality.

Temporal trends (over 30 years), clinical characteristics, outcomes, and gender in patients ≤50 years of age having percutaneous coronary intervention.

Little is known regarding temporal trends in characteristics and outcomes of young (≤50 years) patients who develop symptomatic premature coronary artery disease (CAD). The aim of this study was to describe temporal trends in clinical characteristics and outcomes and gender differences in patients with premature CAD undergoing percutaneous coronary intervention (PCI) over 3 decades. A retrospective analysis of 2,922 consecutive patients ≤50 years of age undergoing PCI from 1980 through 2007 was conducted. Baseline characteristics and in-hospital and long-term outcomes were compared by decade. Gender differences and predictors of mortality were analyzed in the most recent cohort. Although most patients were men (80%), there was an increasing proportion of women over time. An increasing prevalence of diabetes mellitus (10% in 1980 to 1989, 16% in 1990 to 1999, 20% in 2000 to 2007, p <0.001), hypertension (29%, 41%, 57%, p <0.001), and hyperlipidemia (39%, 55%, 73%, p <0.001) coincided with increasing body mass index (28.2 ± 4.6, 29.9 ± 5.8, 30.9 ± 6.7 kg/m(2), p <0.001). The proportion of smokers decreased (84%, 76%, 74%, p <0.001). In-hospital mortality (1.0%, 0.8%, 0.9%, p = 0.93) and long-term mortality at 5 years (6%, 6%, 7%, p = 0.97) did not change over time. In contemporary PCI practice, women with premature CAD were more likely to have diabetes mellitus (25% vs 19%, p = 0.02), single-vessel disease (56% vs 41%, p <0.001), and a bleeding complication. In conclusion, there is an increasing burden of cardiovascular risk factors, related mostly to obesity, in patients with premature CAD requiring PCI. Long-term morbidity or mortality in these patients has not improved over the previous 3 decades.

Novel markers of peripheral arterial disease.

Peripheral arterial disease (PAD), a relatively common manifestation of atherosclerotic vascular disease, is associated with significant morbidity and mortality. Although conventional risk factors contribute to the onset and progression of PAD, the role of 'novel' biomarkers in pathways of inflammation, thrombosis, lipoprotein metabolism, and oxidative stress in determining susceptibility to PAD is being increasingly recognized. Validation of novel risk factors for PAD may allow earlier detection, an improved understanding of disease etiology and progression, and the development of new therapies. In this review, we discuss available evidence for associations between novel circulating markers and several aspects of PAD including disease susceptibility, progression, functional limitation, and adverse outcomes.