Comparison of coronary artery bypass surgery and medical therapy in patients with exercised-induced silent myocardial ischemia: a report from the Coronary Artery Surgery Study (CASS) registry

To determine whether coronary artery bypass surgery would prolong survival in patients with silent myocardial ischemia during exercise testing, the data on 692 such patients from the Coronary Artery Surgery Study (CASS) registry were analyzed. The patients were followed up for up to 7 years after medical (n = 424) or surgical (n = 268) therapy. Stratification of patients into subsets was based on the results of cardiac catheterization. Surgical benefit was greatest in the patients with three vessel coronary artery disease or abnormal left ventricular function. Among the 75 patients with three vessel coronary disease and left ventricular dysfunction, the 7 year survival rate was 37% for the medical group and 90% for the surgical group (p less than 0.0001). Thus, among patients with silent myocardial ischemia during exercise testing in this nonrandomized study, survival appeared to be enhanced by coronary artery bypass surgery in subsets of patients with severe coronary artery disease and abnormal left ventricular function.     

Early mortality of acute myocardial infarction in patients with and without prior coronary revascularization surgery. A Coronary Artery Surgery Study Registry Study.

BACKGROUND. The Coronary Artery Surgery Study (CASS) Registry is used to evaluate the effect of various baseline clinical and angiographic factors on mortality after acute out-of-hospital myocardial infarction (MI) in patients with and without prior coronary bypass surgery. METHODS AND RESULTS. Among the CASS Registry patients, there were 985 medical and 369 surgical patients who had an MI out of the hospital within 3 years after enrollment. In the medical group, 20% died before hospitalization. Medical patients with baseline three-vessel disease or left ventricular (LV) dysfunction were at high risk of immediate death. For medical patients who were hospitalized with MI, mortality was higher for older patients and those with severe angina as well as for those with extensive disease and LV dysfunction. The total 30-day mortality for medical patients was 36%. In the surgical group, 12% died before hospitalization. Surgical patients with LV dysfunction or prior MI were at highest risk of immediate death. For surgical patients hospitalized with MI, mortality was significantly increased only for patients with baseline LV dysfunction. Mortality was not significantly higher for surgical patients with multivessel disease. The total 30-day mortality for surgical patients was 21%. The prior use of aspirin or beta-blockers was not associated with reduced mortality from subsequent MI for either medical or surgical patients. Although the prevalence of cigarette smoking was high among patients who had an MI, cigarette smoking did not alter the infarct-related mortality rate. CONCLUSIONS. The surgical group had lower mortality rates than the medical group both immediately (p = 0.001), after hospitalization (p less than 0.0001), and at 30 days (p less than 0.0001).     

Clinical implications of internal mammary artery bypass grafts: the Coronary Artery Surgery Study experience

From the Coronary Artery Surgery Study Registry, all patients undergoing initial bypass surgery procedures with independent vein grafts were identified. The 950 patients receiving an internal mammary artery bypass graft were compared with the 6027 patients receiving vein graft alone. Improved survival rates with internal mammary artery grafts were noted at hospitals in which these grafts were performed infrequently as well as those in which the internal mammary artery graft was used frequently. The improved survival was noted in patients with normal (p = .004) as well as impaired (p = .004) ventricular function, in men (p = .0001) as well as women (p = .005), in patients over age 65 (p = .01) as well as younger patients (p less than .0001), and in those with (p = .05) or without (p less than .0001) critical stenosis of the left main coronary artery. The internal mammary artery bypass graft was an independent predictor of survival (p = .0004) and reduced the risk of dying by a factor of 0.64. It was concluded that the internal mammary artery graft is the bypass vessel of choice and should not be denied any subgroup.     

The influence of surgery on the natural history of angiographically documented left ventricular aneurysm: the Coronary Artery Surgery Study

Coronary artery bypass surgery with or without aneurysmectomy has been used to treat patients with angiographically defined left ventricular aneurysm. To evaluate whether surgery benefits such patients, we analyzed the data from 1131 patients who were enrolled in the registry of the Coronary Artery Surgery Study. Four hundred sixty-seven patients underwent bypass surgery, of which 238 also had left ventricular resection, and 30 had resection alone. The overall operative mortality was 7.9%; the operative mortality was 7% for bypass alone compared with 9% for bypass surgery plus left ventricular resection (NS). Long-term survival by life-table analysis was similar for both medically and surgically treated patients (69% vs 67%, respectively). Cox survival analysis identified congestive heart failure score, duration of chest pain, extent of coronary disease, left ventricular end-diastolic pressure, age, and surgical therapy as important predictors of outcome. Patient subsets that showed improved survival with surgical therapy after adjustment for inequities in baseline characteristics were patients with three-vessel disease and those patients in moderate- and high-risk subgroups. Surgical therapy significantly reduced symptoms of angina and use of cardiac medications but the incidence of recurrent infarction was similar for both therapies.     

The role of exercise-induced silent myocardial ischemia in patients with abnormal left ventricular function. A report from the Coronary Artery Surgery Study (CASS) registry

To evaluate the significance of ischemic ST depression without anginal chest pain (silent ischemia) during exercise testing among patients with abnormal left ventricular function, the data on 121 such patients with proven coronary artery disease (CAD) from the Coronary Artery Surgery Study (CASS) registry were analyzed. The patients with silent ischemia (group 1) were compared to: 124 CAD patients with both ST depression and angina (symptomatic ischemia, group 2); 159 CAD patients with neither ST depression nor angina (no ischemia, group 3); and 37 patients without CAD (controls). Survival at 7 years with medical therapy was similar for groups 1 (55%) and 2 (60%), but was substantially better for group 3 (73%, p = 0.001). Among group 1 patients with silent ischemia, survival was related to the severity of CAD (p = 0.001). Patients with silent ischemia and three-vessel CAD had a poor 7-year survival rate (37%) when treated medically. A comparable but non-randomized group of patients with silent ischemia and three-vessel CAD who underwent coronary artery bypass surgery had a much better 7-year survival rate (83%, p less than 0.0001). These results suggest that among patients with CAD and abnormal left ventricular function, silent ischemia adversely affects survival and can identify a higher risk subset of patients whose survival might be improved after coronary bypass surgery.     

Prevalence and prognostic significance of silent and symptomatic ischemia after coronary bypass surgery: a report from the Coronary Artery Surgery Study (CASS) randomized population

The prevalence and prognostic significance of postoperative myocardial ischemia, as detected by exercise testing, were prospectively assessed in 174 patients from the Coronary Artery Surgery Study (CASS) randomized surgical population who had exercise testing before and 6 months after coronary artery bypass graft surgery. Whereas the prevalence of symptomatic ischemia significantly decreased postoperatively (52% vs. 6%, p less than 0.001), the frequency of silent myocardial ischemia did not change (30% vs. 29%). Survival at 12 years after bypass surgery based on the 6-month postoperative exercise test results was significantly better for the 112 patients with no ischemia (80%) than for the 51 patients with silent ischemia (68%) or the 11 patients with symptomatic ischemia (45%). These data show that coronary artery bypass graft surgery diminishes the overall prevalence of symptomatic but not silent ischemia and that both silent and symptomatic ischemia adversely affect the postoperative prognosis of these patients.     

CASS in retrospect: lessons from the randomized cohort and registry. Coronary Artery Surgery Study

The Coronary Artery Surgery Study (CASS) was a prospective, randomized evaluation of the value of coronary artery bypass grafting compared with medical therapy for stable, mildly symptomatic coronary artery disease. Also, the CASS registry collected clinic information and follow-up data from 24,959 nonconsecutive patients undergoing cardiac catheterization from 1974 to 1979. CASS has had a major impact on current management of the coronary disease patient and represents an important contribution to the cardiovascular knowledge base. Despite the large size and valuable contributions of CASS, its findings have been widely misinterpreted, especially regarding indications for coronary artery bypass surgery. This review examines CASS from the viewpoint of its methodology and some of its many published reports. A full understanding of CASS is requisite to avoid clinical misapplication of the findings of this study.     

Effects of smoking on survival and morbidity in patients randomized to medical or surgical therapy in the Coronary Artery Surgery Study (CASS): 10-year follow-up. CASS Investigators.

OBJECTIVES. The goal of this study was to ascertain how continued cigarette smoking or smoking cessation related to long-term survival and morbidity in patients with established coronary artery disease managed with medical therapy or coronary bypass surgery. BACKGROUND. Although the association of cigarette smoking with coronary artery disease is well established, the morbidity and mortality associated with smoking behavior in patients with such disease receiving medical or surgical therapy are less well established. METHODS. The 780 patients randomized to medical therapy or coronary bypass surgery in the Coronary Artery Surgery Study (CASS) were subgrouped according to smoking behavior during a mean 11.2-year follow-up interval. Comparisons between smokers and nonsmokers were accomplished by univariate and Cox time-dependent multivariate analyses. RESULTS. Survival at 10 years after entry into the study was 82% among 468 patients who reported no smoking during follow-up (nonsmokers) compared with 77% among the 312 smokers (p = 0.025). Survival was 80% among those who smoked at entry but stopped (quitters) versus 69% among those who continued smoking (p = 0.025). For patients who smoked at baseline and were randomized to bypass surgery, survival at 10 years was 84% among quitters and 68% among nonquitters (p = 0.018); the difference in survival between quitters (75%) and nonquitters (71%) was less among those randomized to medical therapy (p = NS). Among those who smoked at baseline, continued smoking increased the relative risk of death by 1.73. After 10 years, smokers, in comparison with nonsmokers, were less likely to be angina free and more likely to be unemployed and had more activity limitation and more hospital admissions (primarily for chest pain, heart attack, cardiac catheterization, peripheral vascular surgery and stroke). CONCLUSIONS. Thus, among patients with documented coronary artery disease, continued cigarette smoking may result in decreased survival--especially among those undergoing bypass surgery. Moreover, smokers have more angina, more unemployment, a greater limitation of physical activity and more hospital admissions.     

Arterial switch repair to transposition of great arteries: So far so good

The Evaluation of Xience Prime or Xience V versus Coronary Artery Bypass Surgery for Effectiveness of Left Main Revascularization (EXCEL) trial is a multicenter, ongoing trial conducted in patients with left main disease and SYNTAX score ≤ 32 to establish the presumptive advantage of percutaneous coronary intervention (PCI) versus bypass surgery in patients with less complex coronary artery disease than those enrolled in the Synergy between PCI with Taxus and Cardiac Surgery (SYNTAX) trial. In this article, we aimed at critically discussing key features and issues relevant to design and clinical interpretation of this new contemporary trial of left main PCI.     

New-Onset Atrial Fibrillation After PCI or CABG for Left Main Disease: The EXCEL Trial

Background

There is limited information on the incidence and prognostic impact of new-onset atrial fibrillation (NOAF) following percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) for left main coronary artery disease (LMCAD).

Off-pump coronary artery bypass grafting does not reduce lymphocyte activation

OBJECTIVE: In this study, we test the hypothesis that off-pump coronary bypass surgery might result in less lymphocyte activation than on-pump coronary surgery. We also study the behavior of lymphocyte activation markers during and after surgery. BACKGROUND: Coronary artery bypass surgery is known to be associated with changes of inflammatory mediators, immune function, and early phase lymphocyte activation, which could cause postoperative lymphopenia and lymphocyte unresponsiveness. METHODS: We studied lymphocyte activation response in 28 patients randomized to off-pump (n = 13) or on-pump (n = 15) coronary artery bypass surgery. Expression of CD25, CD26, CD69, and DR on T (CD3+) and B (CD19+) lymphocytes on peripheral blood was assessed through flow cytometry. RESULTS: The response of T lymphocytes and their activation markers, as well as B lymphocytes and their activation markers, was similar after on- and off-pump surgery. Overall, T lymphocytes decreased to the lowest level 9 h after surgery and tended to increase later. For B lymphocytes, there was early reduction with increase on the 1st postoperative day. There was early activation of CD69+ and late activation of CD25+ on T lymphocytes. For B lymphocytes, there was early activation of CD69+ and late activation of DR+. CONCLUSIONS: (1) Compared to on-pump cardiopulmonary bypass, off-pump surgery does not reduce lymphocyte activation. (2) Coronary bypass surgery causes the early activation of lymphocytes, as evidenced by the increased expression of lymphocyte activation markers.     

Incidence, imaging analysis, and early and late outcomes of stroke after cardiac valve operation

The aim of this study was to analyze the incidence, topography, and mechanisms of stroke, independent predictors, and late outcome after cardiac valve operations. We retrospectively analyzed prospectively collected data from 2,808 patients (mean age 63 +/- 15 years, n = 1,610, 55% men) who underwent valve surgery with or without concomitant coronary artery bypass grafting from January 1998 to December 2006. Stroke was defined as any new permanent focal neurologic deficit. Overall incidence of stroke was 2.2% (n = 63) and decreased during the study period from 3.3% (1998 to 2002) to 1.3% (2003 to 2006; p = 0.001). The highest stroke rate was observed after double aortic/mitral valve replacement (5.4%) and valve/coronary artery bypass grafting procedures (3.6%). Brain imaging was positive in 74% (n = 43 of 58) and showed ischemic stroke in all patients and hemorrhagic conversion in 28%. Distribution of acute stroke was large territory embolic artery (n = 33, 77%), watershed (n = 7, 16%), and mixed pattern (n = 3, 7%). Multivariate analysis revealed calcified ascending aorta (odds ratio [OR] 2.7), female gender (OR 2.6), ejection fraction <30% (OR 2.3), diabetes (OR 2.2), age >70 years (OR 2.0), and cardiopulmonary bypass time >120 minutes (OR 3.7) as predictors of stroke. Hospital mortality was 24% and 4.6% in patients with and without stroke, respectively. Survival of stroke patients was 78% and 54% at 1 year and 5 years, respectively, and was significantly decreased compared with patients without stroke. Valve pathology including endocarditis did not influence the incidence of stroke. Intraoperative epiaortic scanning may contribute in decreasing the incidence of this complication and may be warranted in all patients undergoing valvular surgery. In conclusion, stroke after valvular surgery is associated with an increased hospital mortality and morbidity and decreased long-term survival.     

Long-term effects of spinal cord stimulation and coronary artery bypass grafting on quality of life and survival in the ESBY study.

AIMS: To assess the long-term outcome regarding quality of life and survival in patients who were included in the ESBY study 1992-1995. The ESBY study (Electrical Stimulation versus Coronary Artery Bypass Surgery in Severe Angina Pectoris) included 104 patients-with severe angina, increased surgical risk and no prognostic benefits from revascularization-randomized to coronary artery bypass grafting or spinal cord stimulation. METHODS AND RESULTS: The ESBY patients' quality of life was analysed using two questionnaires, and 5-year mortality was assessed. Quality of life improved significantly 6 months after spinal cord stimulation and coronary artery bypass grafting, respectively, compared to run-in (P<0.001). The results were consistent after 4.8 years. The 5-year mortality was 27.9%. There were no significant differences between the groups. CONCLUSIONS: Spinal cord stimulation as well as coronary artery bypass grafting offered long-lasting improvement in quality of life. Survival up to 5 years was comparable between the groups. Both methods can be considered as effective treatment options for patients with severe angina, increased surgical risks and estimated to have no prognostic benefits from coronary artery bypass grafting.     

Ten-year outcome after coronary angioplasty in patients with single-vessel coronary artery disease and comparison with the results of the Coronary Artery Surgery Study (CASS)

The 10-year results of randomized trials comparing percutaneous transluminal coronary angioplasty (PTCA) in patients with single-vessel coronary artery disease (CAD) with coronary artery bypass grafting (CABG) and medical treatment are not available yet. The aim of this evaluation was to compare our 10-year follow-up results after PTCA in patients with single-vessel CAD with the 10-year follow-up results after CABG and medical treatment in the Coronary Artery Surgery Study (CASS) trial. We evaluated the clinical outcome of 509 patients with single-vessel CAD 10 years after coronary angioplasty. The data were compared with the results of 214 patients with single-vessel CAD after CABG or medical treatment from the CASS trial. End points were defined as death and myocardial infarction. Statistical evaluation was performed by life-table analysis and 2-sided Fisher's exact test. The rate of survival was 86% 10 years after PTCA compared with 85% after CABG and 82% after medical treatment in patients from the CASS trial (p = NS). Survival free from myocardial infarction was 77% after coronary angioplasty, 70% after CABG, and 72% after medical treatment (p = NS). Thus, in patients with single-vessel CAD, infarct-free survival 10 years after coronary angioplasty compared favorably with the results after bypass surgery or medical treatment from the CASS trial.     

Effect of coronary bypass surgery on survival patterns in subsets of patients with left main coronary artery disease: Report of the collaborative study in coronary artery surgery (CASS)

The 3 year cumulative survival rate of 1,492 patients with left main coronary artery disease (50 percent or greater stenosis of luminal diameter) enrolled in the Collaborative Study in Coronary Artery Surgery (CASS) was 91 percent for the surgical group and 69 percent for patients treated medically (p <0.0001). Mortality was significantly greater in patients with impaired left ventricular function. The difference between medical and surgical therapy was significant for patients who had normal, moderately abnormal and severely impaired left ventricular function and for patients with stenosis of the left main coronary artery of 50 to 59, 60 to 69, 70 to 79 and 80 percent or greater. Aortocoronary bypass surgery did not significantly improve survival in patient subgroups who had (1) a nonstenotic dominant right or balanced coronary circulation, (2) a stenotic dominant right coronary artery and normal left ventricular function, and (3) left main coronary stenosis of 50 to 59 percent and normal or mildly abnormal left ventricular function.The Cox proportional hazards model was used to select baseline variables that were independent predictors of long-term mortality. The model selected left ventricular score, age, congestive heart failure score, hypertension, percent left main coronary arterial stenosis and coronary arterial dominance as the baseline variables most predictive of long-term survival. A clinical and angiographic prognostic risk index developed from these six baseline variables showed significantly improved survival for the surgical cohort in each of four risk categories. In the best and worst risk category, the 3 year survival rate was 97 and 82 percent, respectively, for the surgical group and 85 and 34 percent, respectively, for the medical group (p?0.0002).The data from this observational study show that coronary bypass surgery prolongs life in most patients with left main coronary artery disease, particularly those who have severe narrowing of the left main coronary artery or impaired left ventricular function. The results permit a better understanding of the natural history of left main coronary artery disease and permit a more accurate estimate of long-time survival for individual patients through the use of a clinical-angiographic risk index.     

Usefulness of revascularization of patients with multivessel coronary artery disease before elective vascular surgery for abdominal aortic and peripheral occlusive disease

The Coronary Artery Revascularization Prophylaxis (CARP) study showed no survival benefit with preoperative coronary artery revascularization before elective vascular surgery. The generalizability of the trial results to all patients with multivessel coronary artery disease (CAD) has been questioned. The objective of this study was to determine the impact of prophylactic coronary revascularization on long-term survival in patients with multivessel CAD. Over a 4-year period, 1,048 patients underwent coronary angiography before vascular surgery during screening into the CARP trial. The cohort was composed of registry (n = 586) and randomized (n = 462) patients, and their survival was determined at 2.5 years after vascular surgery. High-risk coronary anatomy without previous bypass surgery included 2-vessel disease (n = 204 [19.5%]), 3-vessel disease (n = 130 [12.4%]), and left main coronary artery stenosis >/=50% (n = 48 [4.6%]). By log-rank test, preoperative revascularization was associated with improved survival in patients with a left main coronary artery stenoses (0.84 vs 0.52, p <0.01) but not those with either 2-vessel (0.80 vs 0.79, p = 0.83) or 3-vessel (0.79 vs 0.71, p = 0.15) disease. In conclusion, unprotected left main coronary artery disease was present in 4.6% of patients who underwent coronary angiography before vascular surgery, and this was the only subset of patients showing a benefit with preoperative coronary artery revascularization.     

Does off-pump coronary revascularization reduce the release of the cerebral markers, S-100beta and NSE?

OBJECTIVES: The aims of this study were to (1) compare the release of S-100 beta and NSE in off-pump coronary artery bypass grafting (CABG) versus on-pump surgery; (2) investigate whether the S-100 beta and NSE serum concentrations correlate with cardiopulmonary bypass (CPB) duration. MATERIALS AND METHODS: Between October 2002 and May 2004, 42 patients undergoing first time CABG surgery were enrolled in the study. The exclusion criteria were: LVEF<35%, age>70 years, previous myocardial infarction, REDO surgery, the presence of valvular heart disease and/or cerebrovascular disease, abnormal preoperative carotid vessels angiography, coronary artery disease involving the distal circumflex artery, renal dysfunction, coagulopathy. The patients were randomly assigned either to undergo on-pump CABG surgery [group I, n=24 patients] or off-pump CABG [group II, n=18 patients]. Blood was not re-transfused from the cardiotomy suction. All patients presenting haemolysis were excluded from the study. RESULTS: The preoperative S-100beta was 0.13+/-0.08 (microg/l) and NSE 7+/-1.5 (microg/l) in group I and 0.12+/-0.1 (microg/l) and 6.9+/-2.7 (microg/l), respectively in group II. Six hours after the surgery, S-100beta in patients of group I reached a maximum level of 1.38+/-0.4 (microg/l) and NSE of 17.7+/-6.5 (microg/l) compared to 0.5+/-0.11 (microg/l) [S-100B] and NSE 8.6+/-4.2 (microg/l) in group II (p=0.001). Three (12%) patients in group I and none (0%) in group II suffered postoperative delirium, p=0.247. No strokes occurred linear regression analysis revealed a strong correlation between cardiopulmonary bypass duration and S-100beta and NSE peak levels, p<0.0021 (r(2)=0.36) and p<0.0001 (r=0.81), respectively. CONCLUSION: Coronary artery bypass surgery with CPB causes a significantly greater increase in NSE and S-100beta serum levels than off-pump surgery and correlates with CPB duration.     

Coronary Artery Surgery Study (CASS): comparability of 10 year survival in randomized and randomizable patients

The Coronary Artery Surgery Study (CASS) includes 780 patients with mild or moderate stable angina pectoris or asymptomatic survivors of a myocardial infarction who were randomized to either medical or surgical therapy and 1,319 patients who were eligible for randomization but were not randomized (randomizable patients). There were no substantial aggregate differences observed in any of the survival comparisons after 10 years of follow-up study between the randomized and randomizable patients assigned to the medical (79% versus 80%) or surgical (82% versus 81%) groups or in patient subgroups stratified according to coronary artery disease extent and left ventricular ejection fraction. Cox regression analyses were done with independent variables known to be predictors of survival, including surgical versus medical therapy and randomized versus randomizable group, to test the null hypothesis of a mortality difference between medical versus surgical assignment according to group assignment (randomized versus randomizable). In no case did the initial group category enter as a significant predictor of survival. The results in the randomizable group reinforce those in the randomized group with respect to the medical versus surgical comparison. Two subgroups are identified with a significant surgical advantage: 1) patients with proximal left anterior descending coronary artery stenosis greater than or equal to 70% and an ejection fraction less than 0.50, and 2) patients with three vessel coronary artery disease and an ejection fraction less than 0.50. In both groups, coronary bypass surgery had a statistically significant beneficial effect on survival (p less than 0.05). After a decade of follow-up, the CASS randomizable patients confirm conclusions reached on the basis of the CASS randomized trial.     

Diabetes in patients undergoing coronary artery bypass grafting. Impact on perioperative outcome

Summary Diabetes mellitus is an established risk factor related to significant morbidity and mortality after coronary artery bypass grafting. Data on 9682 patients undergoing coronary artery bypass grafting either with (n=8917) or without cardiopulmonary bypass (off-pump coronary artery bypass grafting; n=765) were subjected to an univariate analysis to identify potential associations between diabetes mellitus and 26 a priori selected perioperative outcome variables. Those having a significant association with diabetes were then subjected to a stepwise logistic regression model to identify the impact of diabetes as compared to additional 22 different a priori chosen patient related risk factors and treatment variables. Prevalence of outcome variables independently associated with diabetes has been determined in the subgroup of diabetics undergoing coronary artery bypass grafting with cardiopulmonary bypass or off-pump coronary artery bypass grafting surgery to evaluate the effect of avoiding cardiopulmonary bypass on perioperative patient outcome. Diabetes mellitus was defined as glucose intolerance either treated dietary, with oral hypoglycemics or with insulin. According to this definition of diabetes mellitus we found an overall prevalence of 37.1% (coronary artery bypass grafting with cardiopulmonary bypass: 37.5%; off-pump coronary artery bypass grafting: 32.5%). Eleven outcome variables having a significant association with diabetes were identified. Diabetes could be identified as an independent predictor of postoperative delirium, renal dysfunction and respiratory insufficiency. Prevalence of these three variables was lower in diabetics undergoing offpump coronary artery bypass grafting as in those undergoing coronary artery bypass grafting with cardiopulmonary bypass surgery reaching statistical significance with regard to postoperative delirium and respiratory insufficiency. In conclusion, diabetes mellitus is a significant independent predictor for three postoperative outcome variables in coronary artery bypass surgery. Avoiding cardiopulmonary bypass in diabetics seems to have a beneficial effect.     

Adherence to statin therapy in elderly patients after hospitalization for coronary revascularization

Low levels of statin adherence have been documented in patients with coronary artery disease (CAD), but whether coronary revascularization is associated with improved adherence rates has yet to be evaluated. We identified all Medicare beneficiaries enrolled in 2 statewide pharmacy assistance programs who were ≥65 years old, who had been hospitalized for CAD from 1995 through 2004, and who had been prescribed statin therapy within 90 days of discharge (n = 13,130). Statin adherence was measured based on the proportion of days covered with statin therapy after hospital discharge, and full adherence was defined as proportion of days covered ≥80%. Statin adherence was compared in patients with CAD treated with medical therapy (n = 3,714), percutaneous coronary intervention (n = 6,309), or coronary artery bypass graft surgery (n = 3,107). Statin adherence significantly increased over the period of the study from 70.5% to 75.4% (p <0.0001). After hospitalization for CAD, patients treated with percutaneous coronary intervention and coronary artery bypass graft surgery had full adherence rates of 70.6% and 70.2%, respectively. Full adherence rates were significantly lower for patients treated with coronary revascularization compared to patients treated with medical therapy (79.4%, p <0.0001). Independent predictors of higher statin adherence included treatment with medical therapy, later year of hospital admission, white race, previous statin use, and use of other cardiac medications after CAD hospitalization (p <0.01 for all comparisons). In conclusion, in patients receiving invasive coronary treatment, statin adherence remains suboptimal, despite strong evidence supporting their use. Given the health and economic consequences of nonadherence, these findings highlight the need for developing cost-effective strategies to improve medication adherence after coronary revascularization.