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Diederik van Dijk

Publications and source records attributed to Diederik van Dijk.

10 recordsLinked to original sources
PubMed2006

Determinants and prognostic significance of collaterals in patients undergoing coronary revascularization.

There is evidence that coronary collaterals improve the prognosis in patients with acute myocardial infarction (MI). However, there is limited clinical information on the protective role of collaterals in patients with stable coronary artery disease. This information may help risk stratification and the development of novel therapies, such as arteriogenesis and angiogenesis. The relation between collaterals and cardiac death or MI at 1 year after coronary revascularization was studied in 561 patients who were enrolled in a randomized study that compared stent implantation with bypass grafting. Collaterals were assessed on an angiogram using Rentrop's classification and considered present with a Rentrop grade >1. Unadjusted and adjusted odds ratios for cardiac death or MI at 1 year were calculated using univariate and multivariate regression analyses. In addition, determinants of collaterals were assessed using univariate and multivariate analyses. Collaterals were present in 176 patients (31%). The adjusted odds ratio of cardiac death or infarction was 0.18 (95% confidence interval 0.04 to 0.78) in the presence of collaterals. Independent determinants of collaterals were age (odds ratio 0.97, 95% confidence interval 0.95 to 0.99), multivessel disease (odds ratio 1.60, 95% confidence interval 1.02 to 2.51), impaired ventricular function (odds ratio 1.85, 95% confidence interval 1.04 to 3.29), type C lesion (odds ratio 3.72, 95% confidence interval 2.33 to 5.95), and stenosis severity >90% (odds ratio 9.08, 95% confidence interval 4.65 to 17.73). In conclusion, in patients with a low risk profile, the presence of collaterals protects against cardiac death and MI at 1 year after coronary revascularization. Variables that reflect the duration and severity of the atherosclerotic and ischemic burden determine their presence.

Angioplasty, Balloon, Coronary↗
PubMed2006

Risk and determinants of myocardial injury during off-pump coronary artery bypass grafting.

Perioperative myocardial injury (PMI) after coronary revascularization (bypass surgery using cardiopulmonary bypass or percutaneous intervention) is strongly associated with future adverse events, such as death, myocardial infarction, and coronary intervention. The incidence, determinants, and prognostic significance of PMI after bypass surgery without cardiopulmonary bypass (off-pump surgery) are unknown. The study population comprised the patients who were randomized to off-pump surgery in the Octopus Study. PMI was defined by a creatine kinase isoenzyme-MB/total creatine kinase ratio of >5% during the first 48 hours, postoperatively. PMI occurred in 137 of 260 patients (52%). Using multivariate regression analysis, age, female gender, previous myocardial infarction, preoperative nitrate use, preoperative diuretic use, and number of grafts were independently associated with an increased risk of PMI during off-pump surgery. The presence of preoperative coronary collaterals showed a negative association with PMI. The occurrence of PMI had a crude odds ratio of 7.53 (95% confidence interval 1.59 to 35.63) for an adverse cardiac event at 1 year after off-pump surgery. This odds ratio changed little after adjustment for confounders (odds ratio 6.39, 95% confidence interval 1.41 to 28.93). In conclusion, more severe atherosclerotic disease and female gender were associated with an increased risk of perioperative myocardial injury during off-pump bypass surgery, although the presence of coronary collaterals appeared to be protective. Patients with perioperative myocardial injury during off-pump surgery were at a higher risk of adverse cardiac outcomes at 1 year.

Age Factors↗
PubMed2006

Beating heart versus conventional cardiopulmonary bypass: the octopus experience: a randomized comparison of 281 patients undergoing coronary artery bypass surgery with or without cardiopulmonary bypass.

In the Octopus Study, 281 coronary artery bypass surgery patients were randomized to surgery with or without cardiopulmonary bypass. The primary objective was to compare cognitive outcome between off-pump and on-pump coronary artery bypass surgery. Before and after surgery, psychologists administered a battery of 10 neuropsychological tests to the patients. Cognitive decline was defined as a decrease in an individual's performance of at least 20% from baseline, in at least 20% of the main variables. According to this definition, cognitive decline was present in 21% in the off-pump group and 29% in the on-pump group, 3 months after the procedure (P = .15). At 12 months, cognitive decline was present in 31% in the off-pump group and 34% in the on-pump group (P = .69). These results indicated that patients undergoing coronary artery bypass surgery without cardiopulmonary bypass had improved cognitive outcomes 3 months after the procedure, but the effects were limited and became negligible at 12 months. The same definition of cognitive decline was also applied to 112 volunteers not undergoing surgery. The definition labeled 28% of the control subjects as suffering from cognitive decline, 3 months after their first assessment. This suggests that the natural fluctuations in performance during repeated neuropsychological testing should be included in the statistical analysis of cognitive decline. Using an alternative definition of cognitive decline that takes these natural fluctuations in performance into account, the proportions of coronary artery bypass surgery patients displaying cognitive decline were substantially lower. This indicates that the incidence of cognitive decline after coronary artery bypass surgery has been overestimated.

Cardiopulmonary Bypass↗
PubMed2004

Role of coronary collaterals in off-pump and on-pump coronary bypass surgery.

BACKGROUND: Collaterals limit infarct size, preserve viability, and reduce mortality in patients with acute myocardial infarction. In patients with stable coronary disease, collaterals are associated with less angina and ischemia during angioplasty and fewer ischemic events during follow-up. The role of collaterals has not been studied in patients undergoing off-pump or on-pump bypass surgery. METHODS AND RESULTS: The population consisted of the 281 patients randomized to off-pump or on-pump CABG in the Octopus Study. Collaterals were defined on the baseline angiogram with the Rentrop score and were present in 49% and 51% of the patients in the off-pump and on-pump group, respectively. Perioperative myocardial infarction was defined by a creatine kinase-MB to CK ratio >10% and occurred in 18.2% in the off-pump group and 32.5% in the on-pump group. The unadjusted OR of perioperative myocardial infarction in the presence of collaterals was 0.31 (95% CI 0.17 to 0.84) in the off-pump group and 1.06 (95% CI 0.29 to 3.85) in the on-pump group After adjustment for age, gender, hypertension, hypercholesterolemia, diabetes, multivessel disease, ventricular dysfunction, incomplete revascularization, and ischemic time, the OR was 0.34 (95% CI 0.14 to 0.84) in the off-pump group and 1.28 (95% CI 0.30 to 5.40) in the on-pump group, respectively. Kaplan-Meier estimates of event-free survival at 1 year were 87% in patients with and 69% in those without collaterals after off-pump CABG. These estimates were 66% and 63%, respectively, after on-pump CABG. CONCLUSIONS: Collaterals protect against perioperative myocardial infarction during off-pump surgery but not during on-pump surgery and are associated with a better 1-year event-free survival.

Aged↗
PubMed2003

Randomized comparison between stenting and off-pump bypass surgery in patients referred for angioplasty.

BACKGROUND: Stenting improves cardiac outcome in comparison with balloon angioplasty. Compared with conventional surgery, off-pump bypass surgery on the beating heart without cardiopulmonary bypass may reduce morbidity, hospital stay, and costs. The purpose, therefore, was to compare cardiac outcome, quality of life, and cost-effectiveness 1 year after stenting and after off-pump surgery. METHODS AND RESULTS: Patients referred for angioplasty (n=280) were randomly assigned to stenting (n=138) or off-pump bypass surgery. At 1 year, survival free from stroke, myocardial infarction, and repeat revascularization was 85.5% after stenting and 91.5% after off-pump surgery (relative risk, 0.93; 95% CI, 0.86 to 1.02). Freedom from angina was 78.3% after stenting and 87.0% after off-pump surgery (P=0.06). Quality-adjusted lifetime was 0.82 year after stenting and 0.79 year after off-pump surgery (P=0.09). Hospital stay after the initial procedure was 1.43 and 5.77 days, respectively (P<0.01). Stenting reduced overall costs by 2933 dollars (26.2%) per patient (8276 dollars versus 11 209 dollars; P<0.01). Stenting was more cost-effective in 95% of the bootstrap estimates. CONCLUSIONS: At 1 year, stenting was more cost-effective than off-pump surgery while maintaining comparable cardiac outcome and quality of life. Stenting rather than off-pump surgery, therefore, can be recommended as a first-choice revascularization strategy in selected patients.

Aged↗
PubMed2003

A comparison of on-pump and off-pump coronary bypass surgery in low-risk patients.

BACKGROUND: The performance of coronary bypass surgery without cardiopulmonary bypass ("off pump") may reduce perioperative morbidity and costs, but it is uncertain whether the outcome is similar to that involving the use of cardiopulmonary bypass ("on pump"). METHODS: In a multicenter, randomized trial, we randomly assigned 139 patients with predominantly single- or double-vessel coronary disease to on-pump surgery and 142 to off-pump surgery. Cardiac outcome and cost effectiveness were determined one year after surgery. The uncertainty surrounding the cost-effectiveness ratio (cost differences per quality-adjusted year of life gained) was addressed by bootstrapping. RESULTS: At one year, the rate of freedom from death, stroke, myocardial infarction, and coronary reintervention was 90.6 percent after on-pump surgery and 88.0 percent after off-pump surgery (absolute difference, 2.6 percent; 95 percent confidence interval, - 4.6 to 9.8). Graft patency in a randomized subgroup of patients was 93 percent after on-pump surgery and 91 percent after off-pump surgery (absolute difference, 2.0 percent; 95 percent confidence interval, - 6.5 to 10.4). On-pump surgery was associated with $1,839 in additional direct costs per patient ($14,908 vs. $13,069--a difference of 14.1 percent) and an increase in quality-adjusted years of life of 0.83 as compared with 0.82 (difference, 0.01 year; 95 percent confidence interval, - 0.03 to 0.04). Off-pump surgery was more cost effective than on-pump surgery in 95 percent of bootstrap estimates. CONCLUSIONS: In low-risk patients, there was no difference in cardiac outcome at one year between those who underwent on-pump bypass surgery and those who underwent off-pump surgery. Off-pump surgery was more cost effective.

Cardiopulmonary Bypass↗
PubMed2003

Cognitive self-assessment one year after on-pump and off-pump coronary artery bypass grafting.

BACKGROUND: Coronary artery bypass grafting (CABG) is associated with significant cerebral morbidity. This is usually manifested as cognitive decline and may be caused by cardiopulmonary bypass. The primary objective of this study was to explore whether patients report more cognitive failures 1 year after CABG than preoperatively. Secondary objectives were to evaluate whether there is a difference in reported cognitive failures between patients undergoing on-pump and off-pump CABG and whether a difference between CABG patients and healthy control subjects exists. Finally the relation between objective and subjective cognitive functioning was quantified. METHODS: In this prospective study, the Cognitive Failures Questionnaire (CFQ) was assigned preoperatively and 1 year postoperatively to 81 patients who were randomly assigned to undergo off-pump (n = 45) or on-pump (n = 36) CABG. A control sample of 112 age-matched healthy subjects was included who were administered the CFQ once. RESULTS: No difference was found in the total CFQ score (p = 0.222) and CFQ worry score (p = 0.207) between 1 year after CABG and before CABG. There was no difference between on-pump and off-pump CABG (total score, p = 0.458; worry score, p = 0.563). A significant difference was found in CFQ total score between CABG patients and control subjects (p < 0.001), with control subjects reporting more cognitive failures than CABG patients. Finally, patients who showed cognitive decline in the Octopus trial did not have a higher CFQ total score (p = 0.671) and CFQ worry score (p = 0.772) than patients without cognitive decline 1 year after CABG. CONCLUSIONS: The present findings suggest that CABG does not result in a substantial proportion of patients with subjectively experienced cognitive decline 1 year after the procedure, irrespective of the type of surgical technique (on-pump versus off-pump).

Activities of Daily Living↗