Geographic, demographic, and socioeconomic variations in the investigation and management of coronary heart disease in Scotland.
OBJECTIVE: To determine whether age, sex, level of deprivation, and area of residence affect the likelihood of investigation and treatment of patients with coronary heart disease. DESIGN, PATIENTS, AND INTERVENTIONS: Routine discharge data were used to identify patients admitted with acute myocardial infarction (AMI) between 1991 and 1993 inclusive. Record linkage provided the proportion undergoing angiography, percutaneous transluminal coronary angioplasty (PTCA), and coronary artery bypass grafting (CABG) over the following two years. Multiple logistic regression analysis was used to determine whether age, sex, deprivation, and area of residence were independently associated with progression to investigation and revascularisation. SETTING: Mainland Scotland 1991 to 1995 inclusive. MAIN OUTCOME MEASURES: Two year incidence of angiography, PTCA, and CABG. Results-36 838 patients were admitted with AMI. 4831 (13%) underwent angiography, 587 (2%) PTCA, and 1825 (5%) CABG. Women were significantly less likely to undergo angiography (p < 0.001) and CABG (p < 0.001) but more likely to undergo PTCA (p < 0.05). Older patients were less likely to undergo all three procedures (p < 0.001). Socioeconomic deprivation was associated with a reduced likelihood of both angiography and CABG (p < 0.001). There were significant geographic variations in all three modalities (p < 0.001). CONCLUSION: Variations in investigation and management were demonstrated by age, sex, geography, and socioeconomic deprivation. These are unlikely to be accounted for by differences in need; differences in clinical practice are, therefore, likely. (+info)
Detection of Chlamydia pneumoniae but not cytomegalovirus in occluded saphenous vein coronary artery bypass grafts.
BACKGROUND: A causal relation between atherosclerosis and chronic infection with Chlamydia pneumoniae and/or cytomegalovirus (CMV) has been suggested. Whether the unresolved problem of venous coronary artery bypass graft occlusion is related to infection with C pneumoniae and/or CMV has not been addressed. METHODS AND RESUTLS: Thirty-eight occluded coronary artery vein grafts and 20 native saphenous veins were examined. Detection of C pneumoniae DNA was performed by use of nested polymerase chain reaction (PCR). Homogenisates from the specimen were cultured for identification of viable C pneumoniae. Both conventional PCR and quantitative PCR for detection of CMV DNA were applied. Differential pathological changes (degree of inflammation, smooth muscle cell proliferation [MIB-1]) were determined and correlated to the detection of both microorganisms. C pneumoniae DNA could be detected in 25% of occluded vein grafts. Viable C pneumoniae was recovered from 16% of occluded vein grafts. Except for 1 native saphenous vein, all control vessels were negative for both C pneumoniae detection and culture. All pathological and control specimens were negative for CMV DNA detection. Pathological changes did not correlate with C pneumoniae detection. CONCLUSIONS: Occluded aorto-coronary venous grafts harbor C pneumoniae but not CMV. The detection of C pneumoniae in occluded vein grafts warrants further investigation. (+info)
New-onset sustained ventricular tachycardia after cardiac surgery.
BACKGROUND: The de novo occurrence of sustained ventricular tachycardia (VT) after CABG has been described, but the incidence, mortality rate, long-term follow-up, and mechanism are not well defined. METHODS AND RESULTS: This prospective study enrolled consecutive patients undergoing CABG at a single institution. Patients were followed up for the development of sustained VT, and a detailed analysis of clinical, angiographic, and surgical variables associated with the occurrence of VT was performed. A total of 382 patients participated, and 12 patients (3.1%) experienced >/=1 episode of sustained VT 4.1+/-4.8 days after CABG. In 11 of 12 patients, no postoperative complication explained the VT; 1 patient had a perioperative myocardial infarction. The in-hospital mortality rate was 25%. Patients with VT were more likely to have prior myocardial infarction (92% versus 50%, P<0.01), severe congestive heart failure (56% versus 21%, P<0.01), and ejection fraction <0.40 (70% versus 29%, P<0.01). When all 3 factors were present, the risk of VT was 30%, a 14-fold increase. Patients with VT had more noncollateralized totally occluded vessels on angiogram (1.4+/-0.97 versus 0.54+/-0.7, P<0.01), a bypass graft across a noncollateralized occluded vessel (1.50+/-1.0 versus 0.42+/-0.62, P<0.01), and a bypass graft across a noncollateralized occluded vessel to an infarct zone (1.50+/-1.0 versus 0.17+/-0.38, P<0.01). By multivariate analysis, the number of bypass grafts across a noncollateralized occluded vessel to an infarct zone was the only independent factor predicting VT. CONCLUSIONS: The first presentation of sustained monomorphic VT in the recovery period after CABG is uncommon, but the incidence is high in specific clinical subsets. Placement of a bypass graft across a noncollateralized total occlusion in a vessel supplying an infarct zone was strongly and independently associated with the development of VT. (+info)
Renal failure predisposes patients to adverse outcome after coronary artery bypass surgery. VA Cooperative Study #5.
BACKGROUND: More than 600,000 coronary artery bypass graft (CABG) procedures are done annually in the United States. Some data indicate that 10 to 20% of patients who are undergoing a CABG procedure have a serum creatinine of more than 1.5 mg/dl. There are few data on the impact of a mild increase in serum creatinine concentration on CABG outcome. METHODS: We analyzed a Veterans Affairs database obtained prospectively from 1992 through 1996 at 14 of 43 centers performing heart surgery. We compared the outcome after CABG in patients with a baseline serum creatinine of less than 1.5 mg/dl (median 1.1 mg/dl, N = 3271) to patients with a baseline serum creatinine of 1.5 to 3.0 mg/dl (median 1.7, N = 631). RESULTS: Univariate analysis revealed that patients with a serum creatinine of 1.5 to 3.0 mg/dl had a higher 30-day mortality (7% vs. 3%, P < 0.001) requirement for prolonged mechanical ventilation (15% vs. 8%, P = 0.001), stroke (7% vs. 2%, P < 0.001), renal failure requiring dialysis at discharge (3% vs. 1%, P < 0.001), and bleeding complications (8% vs. 3%, P < 0.001) than patients with a baseline serum creatinine of less than 1.5 mg/dl. Multiple logistic regression analyses found that patients with a baseline serum creatinine of less than 1.5 mg/dl had significantly lower (P < 0.02) 30-day mortality and postoperative bleeding and ventilatory complications than patients with a serum creatinine of 1.5 to 3.0 mg/dl when controlling for all other variables. CONCLUSION: These results demonstrate that mild renal failure is an independent risk factor for adverse outcome after CABG. (+info)
Combined carotid endarterectomy and coronary artery bypass graft.
Atherosclerosis is a generalized disease which afflicts a considerable number of patients in both the carotid and coronary arteries. Although the risk of stroke or death use to combined carotid endarterectomy (CEA) and coronary artery bypass graft (CABG) is thought to be higher than that of each individual operation, the combined procedure is generally preferred over staged operations to treat such patients. We performed the combined procedure safely with the aid of intraoperative portable digital subtraction angiography (DSA). This report describes our experience with the operative strategy of simultaneous CEA and CABG. Ninety CEA and 404 CABG were carried out between January 1989 and December 1997. A total of six patients received the combined procedure with the aid of intraoperative DSA; they were studied retrospectively. Postoperative mortality and morbidity after the combined procedure was 0%. In the combined procedure, neurological complications are difficult to detect after CEA because the patient must be maintained under general anesthesia and extracorporeal circulation during the subsequent CABG. However, intraoperative DSA can confirm patency of the internal carotid artery and absence of flap formation after CEA, and the CABG can be performed safely. Intraoperative portable DSA between CEA and CABG is helpful in preventing perioperative stroke in the combined procedure. (+info)
Cyclooxygenase-2 is widely expressed in atherosclerotic lesions affecting native and transplanted human coronary arteries and colocalizes with inducible nitric oxide synthase and nitrotyrosine particularly in macrophages.
Inflammation appears to have a major role in the development of atherosclerotic lesions affecting native and transplanted coronary arteries. The subsequent risk of plaque rupture and acute ischemic events correlates with the degree of inflammation and may be modified by aspirin, an anti-inflammatory cyclooxygenase inhibitor. Cyclooxygenase-2 (Cox-2) and inducible nitric oxide synthase (iNOS) are involved in the inflammatory response via the rapid and exaggerated production of prostanoids and nitric oxide, both of which may have proatherosclerotic effects. These effects may be mediated by the formation of peroxynitrite in the case of nitric oxide and involve "cross talk" between the two enzyme systems. This study aimed to investigate native and transplant atherosclerosis for the presence and distribution of Cox-2 and iNOS. Immunocytochemical studies were performed on atherosclerotic lesions from patients with native (n=12) and transplant (n=5) coronary disease by using antibodies to Cox-2, iNOS, and nitrotyrosine (an indicator of peroxynitrite production). Control tissue was obtained from unused donor hearts and at the time of autopsy. Cox-2 and iNOS colocalized predominantly in macrophages/foam cells in both types of atherosclerosis. Cox-2 expression was also detected in medial smooth muscle cells and endothelial cells, including those of the vasa vasorum. Nitrotyrosine was found in the same distribution as that of iNOS and was colocalized with Cox-2 in macrophages. Cox-2 and iNOS are coexpressed in native and transplant atherosclerosis, possibly allowing for interaction between the enzymes and suggesting an alternative mechanism for the benefits of aspirin via inhibition of Cox-2 activity. (+info)
Contraction-relaxation coupling and impaired left ventricular performance in coronary surgery patients.
BACKGROUND: Dependence of left ventricular (LV) relaxation on cardiac systolic load is a function of myocardial contractility. The authors hypothesized that, if a tight coupling would exist between LV contraction and relaxation, the changes in relaxation rate with an increase in cardiac systolic load would be related to the changes in LV contraction. METHODS: Coronary surgery patients (n = 120) with preoperative ejection fraction >40% were included. High-fidelity LV pressure tracings (n = 120) and transgastric transesophageal echocardiographic data (n = 40) were obtained. Hearts were paced at a fixed rate of 90 beats/min. Effects on contraction were evaluated by analysis of changes in dP/dt(max) and stroke area. Effects on relaxation were assessed by analysis of R (slope of the relation between tau and end-systolic pressure). Correlations were calculated with linear regression analysis using Pearson's coefficient r. RESULTS: Baseline LV end-diastolic pressure was 10+/-3 mm Hg (mean +/- SD). During leg raising, systolic LV pressure increased from 93+/-9 to 107+/-11 mm Hg. The change in dP/dt(max) was variable and ranged from -181 to +254 mm Hg/s. A similar variability was observed with the changes in stroke area, which ranged from -2.0 to +5.5 cm2. Changes in dP/dt(max) and in stroke area were closely related to individual R values (r = 0.87, P<0.001; and r = 0.81, P<0.001, respectively) and to corresponding changes in LV end-diastolic pressure (r = 0.81, P< 0.001; and r = 0.74, P<0.001, respectively). CONCLUSIONS: A tight coupling was observed between contraction and relaxation. Leg raising identified patients who developed a load-dependent impairment of LV performance and increased load dependence of LV relaxation. (+info)
Prognostic value of dobutamine stress echocardiography in predicting cardiac events in patients with known or suspected coronary artery disease.
OBJECTIVES: The study sought to determine the utility of dobutamine stress echocardiography (DSE) in predicting cardiac events in the year after testing. BACKGROUND: Increasingly, DSE has been applied to risk stratification of patients. METHODS: Medical records of 1,183 consecutive patients who underwent DSE were reviewed. The cardiac events that occurred during the 12 months after DSE were tabulated: myocardial infarction (MI), cardiac death, percutaneous transluminal coronary angioplasty (PTCA), and coronary artery bypass surgery (CABG). Patient exclusions included organ transplant receipt or evaluation, recent PTCA, noncardiac death, and lack of follow-up. A positive stress echocardiogram (SE) was defined as new or worsened wall-motion abnormalities (WMAs) consistent with ischemia during DSE. Classification and regression tree (CART) analysis identified variables that best predicted future cardiac events. RESULTS: The average age was 68+/-12 years, with 338 women and 220 men. The overall cardiac event rate was 34% if SE was positive, and 10% if it was negative. The event rates for MI and death were 10% and 8%, respectively, if SE was positive, and 3% and 3%, respectively, if SE was negative. If an ischemic electrocardiogram (ECG) and a positive SE were present, the overall event rate was 42%, versus a 7% rate when ECG and SE were negative for ischemia. Rest WMA was the most useful variable in predicting future cardiac events using CART: 25% of patients with and 6% without a rest WMA had an event. Other important variables were a dobutamine EF <52.5%, a positive SE, an ischemic ECG response, history of hypertension and age. CONCLUSIONS: A positive SE provides useful prognostic information that is enhanced by also considering rest-wall motion, stress ECG response, and dobutamine EF. (+info)