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Don Poldermans

Publications and source records attributed to Don Poldermans.

150 records · Page 9Linked to original sources
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Predicting perioperative cardiac risk.

Cardiovascular complications are the major cause of perioperative morbidity and mortality of patients undergoing major vascular surgery. This is related to the frequent presence of an underlying coronary artery disease. This paper reviews the pathology of perioperative cardiac complications and cardiac risk assessment and risk reduction strategies. Guidelines of the American College of Cardiology and American Heart Association for the evaluation of cardiac risk for noncardiac surgery may provide the necessary framework for the assessment and management of patients undergoing major vascular surgery. Based on the American College of Cardiology and American Heart Association guidelines and data from contemporary studies, patients without risk factors are considered to be at low risk and do not require additional evaluations for coronary artery disease. Patients with 1 or 2 cardiac risk factors represent an intermediate-risk group for perioperative cardiac complications. If beta-blockers are prescribed, the probability of cardiac complications is low and there is no need for further noninvasive testing. Patients with 3 or more risk factors are at high risk for cardiac complications and the use of noninvasive testing may help further refine cardiac risk based on the presence and absence of test-induced myocardial ischemia. beta-Blockers should be prescribed to all patients, and coronary revascularization should be reserved for high-risk patients who have a clearly defined need for revascularization independent of the need for major vascular surgery.

Adrenergic alpha-Agonists↗
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Long-term prognosis after a normal exercise stress Tc-99m sestamibi SPECT study.

BACKGROUND: Patients with a normal stress technetium 99m sestamibi study were shown to have a favorable outcome at intermediate-term follow-up. However, long-term survival has not been studied. The aim of this study was to evaluate the incidence and predictors of mortality and cardiac events at long-term follow-up after a normal exercise stress sestamibi study. Methods and results We studied 218 patients (mean age, 53 +/- 10 years, 108 men) who had normal myocardial perfusion assessed by Tc-99m sestamibi single photon emission computed tomography at rest and during symptom-limited bicycle exercise stress test. Endpoints during a follow-up period of 7.4 +/- 1.8 years were hard cardiac events (cardiac death and nonfatal myocardial infarction) and all-cause mortality. During follow-up, 13 patients died of various causes (cardiac death in 1 patient). Ten patients had nonfatal myocardial infarction (a total of 11 hard cardiac events). By multivariate analysis, independent predictors of cardiac events were history of coronary artery disease (chi(2) = 5, P =.03) and lower exercise heart rate (chi(2) = 12, P =.001). Independent predictors of all-cause mortality were age (chi(2) = 4, P =.05) and exercise heart rate (chi(2) = 5, P =.03). The annual mortality rate was 0.6% in the first 5 years and 1.8% between the sixth and eighth years. The annual hard cardiac event rate was 0.7% in the first 5 years and 1.5% between the sixth and eighth years. Receiver operating characteristic curves identified an exercise heart rate lower than 130 beats/min as the cutoff value that separated patients with regard to their risk for mortality and hard cardiac events. CONCLUSIONS: It is concluded that the annual mortality and cardiac event rate is less than 1% during 5-year follow-up after a normal exercise sestamibi study. Therefore repeated testing would not be required unless there is a change in symptoms. Follow-up should be closer in patients with a history of coronary artery disease and in those who fail to achieve an exercise heart rate of 130 beats/min or greater.

Adult↗
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Risk stratification of patients after myocardial revascularization by stress Tc-99m tetrofosmin myocardial perfusion tomography.

BACKGROUND: The aim of this study was to assess the incremental prognostic value of stress technetium 99m tetrofosmin imaging after myocardial revascularization. METHODS AND RESULTS: We studied 381 patients (aged 60 +/- 10 years, 270 men), 4.5 +/- 3.2 years after myocardial revascularization (coronary artery bypass grafting in 201 patients and percutaneous coronary intervention in 180 patients), who underwent exercise or dobutamine stress tetrofosmin single photon emission computed tomography. Events during a mean follow-up period of 3.5 +/- 1.4 years were cardiac death in 22 patients, nonfatal myocardial infarction in 11 patients (33 hard cardiac events), and late revascularization in 50 patients. There was no incidence of hard cardiac events in the 100 patients with normal perfusion. Hard cardiac events occurred in 19% of patients with reversible perfusion abnormalities and in 4% of patients without them (P <.01). The incidence of hard cardiac events was similar in patients with and without angina before stress testing (17/197 [8.6%] vs 16/184 [8.7%]). In a multivariate analysis model, predictors of cardiac death were stress rate pressure product and abnormal perfusion. Reversible perfusion abnormalities were independently associated with the composite endpoints of cardiac death, nonfatal myocardial infarction, and late revascularization. In an incremental multivariate analysis model, an abnormal scan was additive to clinical data in the prediction of hard cardiac events (model chi(2) = 17 vs 11, P <.01). CONCLUSION: Stress Tc-99m tetrofosmin myocardial perfusion imaging provides independent prognostic information for the prediction of cardiac events after myocardial revascularization. Symptoms are not predictive of outcome, and therefore asymptomatic patients should not be deferred from stress testing. A normal study identifies a very low-risk population in whom no further intervention is required.

Atropine↗
PubMedDate not supplied

Safety and feasibility of cardiac FDG SPECT following oral administration of Acipimox, a nicotinic acid derivative: Comparison of image quality with hyperinsulinemic euglycemic clamping in nondiabetic patients.

BACKGROUND: Image quality of cardiac fluorine-18-deoxyglucose (FDG) studies is highly dependent on the metabolic conditions during the study; hyperinsulinemic euglycemic clamping ensures adequate image quality. However, the approach is time-consuming. Data in a small number of patients suggest that oral administration of a nicotinic acid derivative (Acipimox, 250 mg; Byk, The Netherlands) results in good image quality. METHODS AND RESULTS: The safety and image quality of cardiac FDG single photon emission computed tomography studies after Acipimox administration were evaluated (21 patients, group 2); the results were compared with studies performed during hyperinsulinemic euglycemic clamping (69 patients, group 1). Image quality was assessed visually and quantitatively with use of heart-to-lung, heart-to-liver, and myocardium-to-background ratios. Blood samples were drawn at baseline and at the time of FDG injection to determine levels of glucose, free fatty acids, and insulin. Baseline characteristics of group 1 and 2 patients were comparable. No side effects occurred in group 1. Four patients in group 2 (19%) had paroxysmal flushing. Image quality, assessed visually, was good in 100% of group 1 patients and in 86% of group 2 patients. Images were uninterpretable in only 1 patient in group 2 (5%). All quantitative parameters of image quality (heart-to-lung, heart-to-liver, and myocardium-to-background ratios) were comparable between group 1 and 2 patients. Baseline plasma levels of all substrates were comparable between groups. At the time of FDG injection, plasma levels of glucose and free fatty acids were comparable between groups; insulin was higher in group 1 patients. CONCLUSIONS: Cardiac FDG single photon emission computed tomography after Acipimox is a simple and safe approach that renders comparable image quality to that obtained during hyperinsulinemic euglycemic clamping.

Administration, Oral↗
PubMedDate not supplied

Validation of two risk models for perioperative mortality in patients undergoing elective abdominal aortic aneurysm surgery.

The authors validated 2 clinical risk models for perioperative mortality in patients scheduled for elective open abdominal aortic aneurysm surgery (AAA surgery). They studied 361 patients who underwent elective AAA surgery between 1991 and 1999 (validation population). Two clinical risk models were validated. The first was developed in 238 patients from Leiden University Hospital (Leiden risk model). The Leiden risk model was modified to provide predictions for the validation population based on 6 predictors including age, gender, a history of previous myocardial infarction, congestive heart failure, renal disease, and pulmonary disease. The second was a recently published simpler risk model developed in 820 patients in the UK Small Aneurysm Trial (UK risk model) and included 3 predictors (age and renal and pulmonary comorbidity). Logistic regression was used to quantify the relationship between predictors and outcome (mortality within 30 days of surgery). Validation further included the concordance statistic (c-statistic) for discriminative ability and the Hosmer-Lemeshow test for model reliability. The perioperative mortality in the validation population was 6.6% (24/361). Predictors had similar odds ratios, with particularly strong effects of congestive heart failure, pulmonary disease, and renal impairment. The Leiden risk model had reasonable good ability (c-statistic 0.72) and showed adequate calibration (chi(2)=3.3, p=0.97). It could particularly identify a low-risk group. The UK risk model did not perform well (c-statistic 0.60), showing statistically significant lack of fit (chi(2)=64.9, p<0.001). This study showed similar predictive ability of previously identified predictors for perioperative mortality. The Leiden risk model could identify a low-risk group, while the UK risk model showed a relatively poor performance. The current study supports the use of the Leiden model for preoperative risk assessment.

Aged↗