Impact of myocardial viability and left ventricular lead location on clinical outcome in cardiac resynchronization therapy recipients with ischemic cardiomyopathy.

INTRODUCTION: Cardiac resynchronization therapy (CRT) recipients with ischemic cardiomyopathy (ICM) have scar segments that may limit ventricular resynchronization and clinical response. The impact of myocardial viability at the left ventricular (LV) pacing site on CRT response is poorly elucidated. METHODS AND RESULTS: A retrospective cohort of 160 ICM patients with single photon emission computed tomography-myocardial perfusion imaging before device implantation were included. Coronary venous angiography and chest radiographs helped classify segmental location of LV lead (LVL). The primary outcome was a composite of heart failure (HF) hospitalization and mortality at 3 years, and secondary outcome was change in systolic function at 6 months. The patients were divided into groups based on the myocardial substrate at the site of LVL: LVL on or adjacent to (1) normal myocardium (LVL-N, n = 64), (2) segmental scar (LVL-S, n = 62), and (3) scar and ischemia (LVL-SI, n = 34). Upon follow-up, 75 (47%) patients reached primary endpoint with a higher incidence noted in LVL-S (60%), and LVL-SI (53%), compared to 31% in LVL-N (P = 0.004). Kaplan Meier method demonstrated poor event free survival for primary outcome in LVL-S (P = 0.002), and LVL-SI (P = 0.03). In Cox proportional hazard model, LVL-S (HR: 2.26, P = 0.004), and LVL-SI (1.9, P = 0.047) were independent predictors of primary outcome. CONCLUSION: In CRT recipients with ICM, scar and reversible ischemia in or adjacent to LV pacing site were independent predictors of HF hospitalization and death.

Long term outcomes in octogenarians undergoing percutaneous coronary intervention: comparison of bare metal versus drug eluting stent.

BACKGROUND: Octogenarians have been under-represented in percutaneous coronary intervention (PCI) trials, thus making difficult to choose the best type of stent in this patient population. We compared the outcomes of drug eluting (DES) and bare metal stent (BMS) at one year after implantation in this special population. METHODS: A total of 320 consecutive patients over 80 years undergoing PCI with BMS (n=218) or DES (n=102) were retrospectively studied. One year major adverse cardiac events (MACEs) defined as cardiac death, non-fatal myocardial infarction and target vessel revascularization (TVR) were compared between the two groups. Cox regression analysis was used for data analysis. RESULTS: The one year incidence of MACE was higher in the BMS group (18.8% vs 9.8%, adjusted hazard ratio [HR] 2.33; 95% confidence interval [C.I.]: 1.12 to 4.86 p=0.02). Diabetes mellitus was an independent predictor for increased MACE (adjusted HR: 1.99; C.I. 1.06 to 3.77, p=0.03). One year incidence of TVR was higher in the BMS group (10.0% vs 3.9% adjusted HR: 2.94; C.I. 1.01 to 8.59 p=0.045). There was no difference in cardiac death between the two groups. CONCLUSION: During one year follow-up, octogenarians treated with BMS had an increased risk of MACE compared with those treated with DES. DES should be preferred in indications recognized from current PCI guidelines.

Outcome of patients with regadenoson-induced ST-segment depression but normal perfusion on single-photon emission computed tomography.

The prognostic significance of ischemic electrocardiographic (ECG) changes during Regadenoson vasodilator stress in patients with normal single-photon emission computed tomographic myocardial perfusion imaging (SPECT-MPI) is not well described. Of 2473 patients who underwent Regadenoson vasodilator stress testing, 43 (77% women, mean age 72 ± 10 years) patients were included in the study. During a mean follow-up of 14 ± 7 months, cardiac death occurred in 1 patient; 5 patients underwent coronary revascularization and none had myocardial infarction. The annual rate of cardiac death and coronary revascularization was 1.9% and 9.9%, respectively. The finding of ischemic ECG changes with normal SPECT-MPI during regadenoson vasodilator stress testing is uncommon, occurs primarily in older women, and is associated with moderately higher subsequent cardiac event rate.

Exercise-induced ST-segment elevation in ECG lead aVR is a useful indicator of significant left main or ostial LAD coronary artery stenosis.

OBJECTIVES: The authors tested the hypothesis that exercise treadmill testing (ETT)-induced ST-segment elevation (STE) in electrocardiographic lead aVR is an important indicator of significant left main coronary artery (LMCA) or ostial left anterior descending coronary artery (LAD) stenosis. BACKGROUND: Although STE in lead aVR is an indicator of LMCA or very proximal LAD occlusion in acute coronary syndromes, its predictive power in the setting of ETT is uncertain. METHODS: Rest and stress electrocardiograms, clinical and stress test parameters, and single photon-emission computed tomographic myocardial perfusion imaging (MPI) data, when available, were obtained in 454 subjects (378 with MPI) who underwent cardiac catheterization and standard Bruce ETT ≤ 6 months before catheterization. Patients were selected for LMCA or ostial LAD disease (≥ 50% stenosis) with or without other coronary artery disease (CAD), CAD (≥ 70% stenosis) without significant LMCA or ostial LAD, or no significant CAD. Univariate followed by multivariate logistic regression analyses of clinical, electrocardiographic, stress test, and single photon-emission computed tomographic MPI variables were used to identify significant correlates of LMCA or ostial LAD stenosis. Bayesian analysis of the data also was performed. RESULTS: LMCA (n = 38) or ostial LAD (n = 42) stenosis occurred in 75 patients (5 patients had both). The remainder had CAD without LMCA or ostial LAD stenosis (n = 276) or no CAD (n = 103). In multivariate analysis, the strongest predictor was stress-induced STE in lead aVR (p < 0.0001, area under the curve 0.82). Both left ventricular ejection fraction (after stress) and percent reversible LAD ischemia on single photon-emission computed tomographic MPI also contributed significantly in multivariate analysis (p < 0.005 and p < 0.05, respectively, areas under the curve 0.60 and 0.64, respectively). Although additional electrocardiographic, stress test, and MPI variables were significant univariate predictors, none was statistically significant in multivariate analysis. At 1-mm STE in lead aVR, sensitivity for LMCA or ostial LAD stenosis was 75%, specificity was 81%, overall predictive accuracy was 80%, and post-test probability increased nearly 3 times from 17% to 45%. CONCLUSIONS: Stress (ETT)-induced STE in lead aVR is an important indicator of significant LMCA or ostial LAD stenosis and should not be ignored.

Increased prevalence of primary biliary cirrhosis near Superfund toxic waste sites.

Primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC) are uncommon liver diseases of unknown etiology. Reported clustering of PBC cases may be due to environmental factors. Individuals with PBC have a high prevalence of thyroid disease and thyroid disease is reportedly more prevalent near Superfund toxic waste sites (SFS). The objective of this study was to examine the prevalence and potential clustering of individuals with PBC and PSC near SFS. De-identified clinical and demographic data were used to determine the observed prevalence for each New York City zip code (n = 174) and borough (n = 5) of patients with PBC (PBC-OLT) or PSC (PSC-OLT) who were listed for liver transplantation. The expected prevalence was calculated using Organ Procurement and Transfer Network (OPTN) and U.S. Census data. Both PBC-OLT patients and patients not listed for liver transplantation (PBC-MSSM) were included in the cluster analysis. Prevalence ratios of PBC-OLT and PSC-OLT cases were compared for each zip code and for each borough with regard to the proximity or density of SFS, respectively. SaTScan software was used to identify clusters of PBC-OLT cases and PBC-MSSM cases. Prevalence ratio of PBC-OLT, not PSC-OLT, was significantly higher in zip codes containing or adjacent to SFS (1.225 vs. 0.670, respectively, P = .025). The borough of Staten Island had the highest prevalence ratio of PBC-OLT cases and density of SFS. Significant clusters of both PBC-OLT and PBC-MSSM were identified surrounding SFS. In conclusion, toxin exposure may be a risk factor influencing the clustering of PBC cases.