Relative importance of patient, procedural and anatomic risk factors for early vein graft thrombosis after coronary artery bypass graft surgery.

AIM: The aim of the present study was to investigate the relative importance of a wide array of patient demographic, procedural, anatomic and perioperative variables as potential risk factors for early saphenous vein graft (SVG) thrombosis after coronary artery bypass graft (CABG) surgery. METHODS: The patency of 611 SVGs in 291 patients operated on at four different hospitals enrolled in the Reduction in Graft Occlusion Rates (RIGOR) study was assessed six months after CABG surgery by multidetector computed tomography coronary angiography or clinically-indicated coronary angiography. The odds of graft occlusion versus patency were analyzed using multilevel multivariate logistic regression with clustering on patient. RESULTS: SVG failure within six months of CABG surgery was predominantly an all-or-none phenomenon with 126 (20.1%) SVGs totally occluded, 485 (77.3%) widely patent and only 16 (2.5%) containing high-grade stenoses. Target vessel diameter ≤ 1.5 mm (adjusted OR 2.37, P=0.003) and female gender (adjusted OR 2.46, P=0.01) were strongly associated with early SVG occlusion. In a subgroup analysis of 354 SVGs in which intraoperative graft blood flow was measured, lower mean flow was also significantly associated with SVG occlusion when analyzed as a continuous variable (adjusted OR 0.984, P=0.006) though not when analyzed dichotomously, <40 mL/min versus ≥ 40 mL/min (adjusted OR 1.86, P=0.08). CONCLUSION: Small target vessel diameter, female gender and low mean graft blood flow are significant risk factors for SVG thrombosis within six months of CABG surgery in patients on postoperative aspirin therapy. This information may be useful in guiding revascularization strategies in selected patients.

Specialty of principal care physician and Medicare expenditures in patients with coronary artery disease: impact of comorbidity and severity.

OBJECTIVE: To explore differences in expenditures for elderly patients with acute and chronic coronary artery disease according to the specialty of the principal care physician. STUDY DESIGN: Retrospective analysis of Medicare claims. PATIENTS AND METHODS: A total of 250,514 patients with coronary artery disease (International Classification of Diseases, Ninth Revision, Clinical Modification [ICD-9-CM] codes 410-414) were drawn from a national random sample of 1992 Medicare expenditures. Patients were classified by the physician type with the highest number of Medicare Part B outpatient claims into a cardiologist group and a generalist group. The outcome was mean total expenditures, stratifying (1) by comorbidity as measured by the modified Charlson Index and (2) by severity defined as the proportion of patients with acute myocardial infarction or unstable angina. RESULTS: Those patients in the cardiologist group had lower comorbidity and higher severity than those in the generalist group. Overall mean expenditures were significantly higher for the cardiologist group than for the generalist group ($7658 vs $6047; P < .001). These differences in mean expenditures were evident at each level of comorbidity. However, when stratified by severity of diagnosis, differences were seen predominantly in those with acute diagnoses. For those with either acute myocardial infarction or unstable angina, the mean expenditures were higher for the cardiologist group than for the combined generalist group ($15,378 vs $12,260; P < .001); however, the mean expenditures for those with only chronic conditions were similar ($4856 vs $4745; P = .53). CONCLUSION: Expenditures were higher when cardiologists were the principal care physicians treating patients with acute disease but not chronic disease.

Spot urinary albumin-creatinine ratio predicts left ventricular hypertrophy in young hypertensive African-American men.

Hypertensive patients with target organ damage are at increased cardiovascular risk, and should be treated most aggressively. The association between urinary albumin excretion and left ventricular hypertrophy (LVH) in prior studies is inconsistent, and has not been described using a single, random spot urine specimen. Therefore, we evaluated the association between the urinary albumin creatinine ratio (ACR) and left ventricular (LV) mass and also tested the hypothesis that a simple random, single-void urine ACR would identify high risk young, hypertensive, African-American men. We measured echocardiographic LV mass and a random spot urinary ACR in 109 untreated, hypertensive, young, inner city, African-American men. The mean age was 41 +/- 6 years and the mean blood pressure (BP) was 157 +/- 19/107 +/- 13 mm Hg. Microalbuminuria (ACR 30 to 300 mg/g) was present in 22% of subjects. The ACR is higher in the men with LVH than in the men without LVH (P < .05). Increased ACR is a predictor of increased LV mass index (P < .003) using multiple linear regression. An ACR >30 mg/g has a sensitivity of 33% and a specificity of 82% for the diagnosis of echocardiographic LVH. In conclusion, elevated random spot ACR is a marker of increased LV mass, independent of BP, in young urban African-American men with hypertension, and may help to determine the aggressiveness of antihypertensive therapy in this high-risk group.

Myocarditis and long-term survival in peripartum cardiomyopathy.

BACKGROUND: The reported mortality rate of peripartum cardiomyopathy (PPCM) is high, although the potential for spontaneous recovery of ventricular function is well established. The prevalence of myocarditis in PPCM has varied widely between studies. The purposes of this study were to define the long-term prognosis in a referral population of patients with PPCM, to determine the prevalence of myocarditis on endomyocardial biopsy in this population, and to identify clinical variables associated with poor outcome. METHODS: We analyzed clinical, echocardiographic, hemodynamic, and histologic features of 42 women with PPCM evaluated at our institution over a 15-year period. Each patient underwent an extensive evaluation, including echocardiography, endomyocardial biopsy, and right heart catheterization. Data were analyzed to identify features at initial examination associated with the combined end point of death or cardiac transplantation by the use of Kaplan-Meier survival curves and a Cox proportional hazards model. RESULTS: Three (7%) patients died and 3 (7%) patients underwent heart transplantation during a median follow-up of 8.6 years. Endomyocardial biopsy demonstrated a high prevalence of myocarditis (62%), but the presence or absence of myocarditis was not associated with survival. Of the prespecified variables assessed, only decreased left ventricular stroke work index was associated with worsened outcome. CONCLUSIONS: In patients with PPCM, (1) long-term survival is better than has been historically reported, (2) the prevalence of myocarditis is high, and (3) decreased left ventricular stroke work index is associated with worse clinical outcomes.

Lack of benefit for intravenous thrombolysis in patients with myocardial infarction who are older than 75 years.

BACKGROUND: The benefit of intravenous thrombolytic therapy in elderly patients with myocardial infarction is uncertain. There are no randomized trials of thrombolytic efficacy or observational studies of clinical effectiveness that focus specifically on the elderly. METHODS AND RESULTS: To determine whether thrombolytic therapy for elderly patients is associated with a survival advantage in a large observational database, we conducted a retrospective cohort study of 7864 Medicare fee-for-service patients aged 65 to 86 years with the primary discharge diagnosis of acute myocardial infarction who were admitted with clinical and ECG indications for thrombolytic therapy and no absolute contraindications. The study included all US acute care nongovernment hospitals without on-site angioplasty capability. Using proportional-hazards methods, we found that in a comprehensive multivariate model, there was a significant interaction (P<0.001) between age and the effect of thrombolytic therapy on 30-day mortality rates. For patients 65 to 75 years old, thrombolytic therapy was associated with a survival benefit, consistent with randomized trials. Among patients aged 76 to 86 years, thrombolytic therapy was associated with a survival disadvantage, with a 30-day mortality hazard ratio of 1.38 (95% CI 1. 12 to 1.71, P=0.003). For these patients, there was no benefit from thrombolytic therapy in any clinical subgroup. CONCLUSIONS: In nationwide clinical practice, thrombolytic therapy for patients >75 years old is unlikely to confer survival benefit and may have a significant survival disadvantage. Reperfusion research that is focused on elderly patients is urgently needed.

Inducible nitric oxide synthase protection against coxsackievirus pancreatitis.

Coxsackievirus infection causes myocarditis and pancreatitis in humans. In certain strains of mice, Coxsackievirus causes a severe pancreatitis. We explored the role of NO in the host immune response to viral pancreatitis. Coxsackievirus replicates to higher titers in mice lacking NO synthase 2 (NOS2) than in wild-type mice, with particularly high viral titers and viral RNA levels in the pancreas. Mice lacking NOS have a severe, necrotizing pancreatitis, with elevated pancreatic enzymes in the blood and necrotic acinar cells. Lack of NOS2 leads to a rapid increase in the mortality of infected mice. Thus, NOS2 is a critical component in the immune response to Coxsackievirus infection.

Contrasting views of physicians and nurses about an inpatient computer-based provider order-entry system.

OBJECTIVE: Many hospitals are investing in computer-based provider order-entry (POE) systems, and providers' evaluations have proved important for the success of the systems. The authors assessed how physicians and nurses viewed the effects of one modified commercial POE system on time spent patients, resource utilization, errors with orders, and overall quality of care. DESIGN: Survey. MEASUREMENTS: Opinions of 271 POE users on medicine wards of an urban teaching hospital: 96 medical house officers, 49 attending physicians, 19 clinical fellows with heavy inpatient loads, and 107 nurses. RESULTS: Responses were received from 85 percent of the sample. Most physicians and nurses agreed that orders were executed faster under POE. About 30 percent of house officers and attendings or fellows, compared with 56 percent of nurses, reported improvement in overall quality of care with POE. Forty-four percent of house officers and 34 percent of attendings/fellows reported that their time with patients decreased, whereas 56 percent of nurses indicated that their time with patients increased (P < 0.001). Sixty percent of house officers and 41 percent of attendings/fellows indicated that order errors increased, whereas 69 percent of nurses indicated a decrease or no change in errors. Although most nurses reported no change in the frequency of ordering tests and medications with POE, 61 percent of house officers reported an increased frequency. CONCLUSION: Physicians and nurses had markedly different views about effects of a POE system on patient care, highlighting the need to consider both perspectives when assessing the impact of POE. With this POE system, most nurses saw beneficial effects, whereas many physicians saw negative effects.

The association between hospital volume and survival after acute myocardial infarction in elderly patients.

BACKGROUND: Patients with chest pain thought to be due to acute coronary ischemia are typically taken by ambulance to the nearest hospital. The potential benefit of field triage directly to a hospital that treats a large number of patients with myocardial infarction is unknown. METHODS: We conducted a retrospective cohort study of the relation between the number of Medicare patients with myocardial infarction that each hospital in the study treated (hospital volume) and long-term survival among 98,898 Medicare patients 65 years of age or older. We used proportional-hazards methods to adjust for clinical, demographic, and health-system-related variables, including the availability of invasive procedures, the specialty of the attending physician, and the area of residence of the patient (rural, urban, or metropolitan). RESULTS: The patients in the quartile admitted to hospitals with the lowest volume were 17 percent more likely to die within 30 days after admission than patients in the quartile admitted to hospitals with the highest volume (hazard ratio, 1.17; 95 percent confidence interval, 1.09 to 1.26; P<0.001), which resulted in 2.3 more deaths per 100 patients. The crude mortality rate at one year was 29.8 percent among the patients admitted to the lowest-volume hospitals, as compared with 27.0 percent among those admitted to the highest-volume hospitals. There was a continuous inverse dose-response relation between hospital volume and the risk of death. In an analysis of subgroups defined according to age, history of cardiac disease, Killip class of infarction, presence or absence of contraindications to thrombolytic therapy, and time from the onset of symptoms, survival at high-volume hospitals was consistently better than at low-volume hospitals. The availability of technology for angioplasty and bypass surgery was not independently associated with overall mortality. CONCLUSIONS: Patients with acute myocardial infarction who are admitted directly to hospitals that have more experience treating myocardial infarction, as reflected by their case volume, are more likely to survive than are patients admitted to low-volume hospitals.

Usefulness of transesophageal echocardiography in predicting mortality and morbidity in stroke patients without clinically known cardiac sources of embolus.

This study tested the hypothesis that stroke patients without a cardiac source of embolism suspected by clinical examination can be risk stratified by transesophageal echocardiography. Forty ischemic stroke patients without atrial fibrillation, prosthetic valves, ejection fraction < 20%, or recent myocardial infarction underwent multiplane transesophageal echocardiography: 24 (designated high risk) had > or = 1 of the following: left heart thrombus, vegetation, mass or spontaneous echo contrast, mobile ascending aortic or arch debris, patent foramen ovale, atrial septal defect or aneurysm, mitral annular calcification, mitral valve thickening, prolapse or mitral valve strands. End points were death, recurrent stroke, transient ischemic attack, myocardial infarction or peripheral embolism. Thirty-eight patients (95%) (23 high, 15 low risk) were followed for 14 +/- 8 months: 9 (24%) died of vascular causes including 4 who had a cardiac cause of death and 5 who had fatal strokes. Eight had recurrent strokes (4 nonfatal) and 1 nonfatal myocardial infarction occurred. Cardiovascular survival was predicted by transesophageal echocardiography: survival rates were 92% (low risk) and 63% (high risk) at 24 months (p = 0.036). Left atrial enlargement was independently associated with death from stroke (fatal stroke occurred in 25% of those with atrial enlargement compared to 8% of those with normal atrial dimension, p < or = 0.03), as was left atrial spontaneous echo contrast (50% died vs 9% without contrast, p < or = 0.03). Left ventricular hypertrophy and aortic atherosclerosis were both associated with the risk of recurrent stroke (30% of patients with ventricular hypertrophy had recurrent stroke compared to 10% with normal wall thickness (p < or = 0.05); 30% with aortic atherosclerosis had a recurrent stroke compared to none with a normal aorta (p < or = 0.05). Thus, transesophageal echocardiography clearly identifies patients at a high risk for cardiovascular mortality and morbidity after stroke despite an unsuspected source of embolism by clinical examination.