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Don Poldermans

Publications and source records attributed to Don Poldermans.

At least 127 records · Page 7Linked to original sources
PubMed2003

Relation between QT dispersion and myocardial viability in ischemic cardiomyopathy.

The aim of this study was to evaluate the relation between QT dispersion and myocardial viability as assessed by single-photon emission computed tomography. The study population included 97 consecutive patients with severely impaired left ventricular function secondary to chronic coronary artery disease. Patients with a low QT dispersion had a substantial amount of viable myocardium, whereas patients with a high QT dispersion had predominantly nonviable scar tissue.

Aged↗
PubMed2003

Early versus delayed revascularization in patients with ischemic cardiomyopathy and substantial viability: impact on outcome.

BACKGROUND: Patients with ischemic cardiomyopathy and viable myocardium may improve in function and prognosis following revascularization. Delayed revascularization may result in less favorable outcome, and therefore the impact of timing of revascularization on long-term outcome was evaluated. METHODS AND RESULTS: Patients (n=85) with ischemic cardiomyopathy and substantial viability (>or=25% of the left ventricle) on dobutamine stress echocardiography underwent surgical revascularization. Based on the waiting time for revascularization, patients were divided into 2 groups: early ( 1 month) revascularization. Left ventricular ejection fraction (LVEF) was assessed before and 9 to 12 months after revascularization; follow-up data were acquired up to 2 years after revascularization. Hence, 40 patients underwent early (20+/-12 days) and 45 late (85+/-47 days) revascularization. Baseline characteristics of the two groups were comparable. Preoperative deaths were 0 in the early and 2 in the late group. Patients with early revascularization remained shorter time in the intensive care unit (2.4+/-1.5 days versus 5.9+/-2.1 days for the late group, P<0.05). Low output syndrome was observed more frequently in the late group (8% versus 22%, P=0.06). On long-term follow-up, mortality (5% versus 20%, P<0.05) and re-hospitalization for heart failure (10% versus 24%, NS) were higher in the late group. LVEF improved from 28+/-9% to 40+/-12% (P<0.05) in the early group and remained unchanged in the late group (27+/-10% versus 25+/-7%, NS). CONCLUSIONS: Patients with ischemic cardiomyopathy and viable myocardium benefit from early revascularization (with improvement in LVEF and favorable prognosis), whereas delayed revascularization of these patients is associated with worse outcome.

Cardiac Output, Low↗
PubMed2003

Effect of atorvastatin on myocardial contractile reserve assessed by tissue Doppler imaging in moderately hypercholesterolemic patients without heart disease.

An improvement in myocardial longitudinal systolic velocities, assessed by pulsed-wave tissue Doppler imaging during low-dose dobutamine infusion, was observed at 6-month follow-up after 6 months of treatment with atorvastatin. Our findings indicate a favorable effect of atorvastatin on contractile reserve, possibly through an enhancement of flow-dependent coronary dilatation during stress.

Aged↗
PubMed2003

Preoperative comparison of different noninvasive strategies for predicting improvement in left ventricular function after coronary artery bypass grafting.

Thallium-201 (Tl-201) imaging and dobutamine stress echocardiography (DSE) are the most frequently used tests in the clinical setting for assessing viability. However, Tl-201 has a suboptimal specificity and DSE a suboptimal sensitivity to predict functional improvement after revascularization. F18-fluorodeoxyglucose (FDG) imaging is considered highly accurate, but availability is limited. Sequential imaging of Tl-201 and DSE may improve accuracy for assessing viability and may be comparable to FDG. Forty-seven patients with ischemic cardiomyopathy underwent Tl-201 single-photon emission computed tomography (SPECT) at rest (4-hour delayed imaging), DSE, and FDG SPECT before bypass surgery. Sensitivity, specificity, and accuracy of 2 sequential strategies were compared with those of FDG SPECT. Strategy 1 considered Tl-201 imaging as the first step, followed by DSE in patients with an intermediate likelihood of viability on Tl-201. Strategy 2 considered DSE as the first step, followed by Tl-201 imaging. Left ventricular ejection fraction was assessed before and 6 months after revascularization, and improvement of >/=5% was considered significant. Tl-201 had a high sensitivity (95%, p <0.05 vs DSE) with a low specificity (57%, p <0.05 vs DSE). DSE had a low sensitivity (63%, p <0.05 vs Tl-201) with a high specificity (89%, p <0.05 vs Tl-201). Both strategies 1 and 2 resulted in high sensitivities (89% and 89%, respectively) and high specificities (89% and 86%, respectively), compared with FDG SPECT (sensitivity 89%, specificity 86%). Sequential testing by Tl-201 SPECT and DSE has a comparable accuracy to FDG SPECT to predict improvement in left ventricular ejection fraction after revascularization. In centers without access to FDG, sequential imaging with Tl-201 and DSE offers an accurate alternative for assessing myocardial viability.

Aged↗
PubMed2003

Individual prediction of functional recovery after coronary revascularization in patients with ischemic cardiomyopathy: the scar-to-biphasic model.

Currently, the prediction of improvement of left ventricular (LV) ejection fraction (EF) after revascularization in patients with ischemic cardiomyopathy relies only on viable myocardium extent, whereas both the amount of viable and scar tissue may be important. A model was developed, based on the amount of viable and nonviable myocardium, to predict functional recovery. Viable and scarred myocardium was defined by dobutamine stress echocardiography (DSE) in 108 consecutive patients. LVEF before and 9 to 12 months after revascularization was assessed by radionuclide ventriculography; an improvement of > or =5% was considered significant. In the 1,089 dysfunctional segments (63%), DSE elicited biphasic response in 216 segments (20%), sustained improvement in 205 (19%), worsening in 43 (4%), and no change in 625 (57%). LVEF improved in 39 patients (36%). Only the numbers of biphasic and scar segments were predictors of improvement or no improvement of LVEF (odds ratio 1.5, 95% confidence interval 1.2 to 1.7, p <0.0001 for biphasic segments; odds ratio 0.8, 95% confidence interval 0.7 to 0.9, p <0.0005 for scarred segments). The sustained improvement and worsening pattern were not predictive of improvement or no improvement. A regression function, based on the number of scar and biphasic segments, showed that the likelihood of recovery was 85% in patients with extensive biphasic tissue and no scars and 11% in patients with extensive scars and no biphasic myocardium. Patients with a mixture of scar and biphasic tissue had an intermediate likelihood of improvement (50%). In patients with ischemic cardiomyopathy and a mixture of viable and nonviable tissue, both numbers of viable and nonviable segments should be considered to accurately predict functional recovery after revascularization.

Aged↗
PubMed2003

Statins are associated with a reduced incidence of perioperative mortality in patients undergoing major noncardiac vascular surgery.

BACKGROUND: Patients undergoing major vascular surgery are at increased risk of perioperative mortality due to underlying coronary artery disease. Inhibitors of the 3-hydroxy-3-methylglutaryl coenzyme A (statins) may reduce perioperative mortality through the improvement of lipid profile, but also through the stabilization of coronary plaques on the vascular wall. METHODS AND RESULTS: To evaluate the association between statin use and perioperative mortality, we performed a case-controlled study among the 2816 patients who underwent major vascular surgery from 1991 to 2000 at the Erasmus Medical Center. Case subjects were all 160 (5.8%) patients who died during the hospital stay after surgery. From the remaining patients, 2 controls were selected for each case and were stratified according to calendar year and type of surgery. For cases and controls, information was obtained regarding statin use before surgery, the presence of cardiac risk factors, and the use of other cardiovascular medication. A vascular complication during the perioperative phase was the primary cause of death in 104 (65%) case subjects. Statin therapy was significantly less common in cases than in controls (8% versus 25%; P<0.001). The adjusted odds ratio for perioperative mortality among statin users as compared with nonusers was 0.22 (95% confidence interval 0.10 to 0.47). Similar results were obtained in subgroups of patients according to the use of cardiovascular therapy and the presence of cardiac risk factors. CONCLUSIONS: This case-controlled study provides evidence that statin use reduces perioperative mortality in patients undergoing major vascular surgery.

Adolescent↗
PubMed2003

Acute myocardial infarction.

Acute myocardial infarction is a common disease with serious consequences in mortality, morbidity, and cost to the society. Coronary atherosclerosis plays a pivotal part as the underlying substrate in many patients. In addition, a new definition of myocardial infarction has recently been introduced that has major implications from the epidemiological, societal, and patient points of view. The advent of coronary-care units and the results of randomised clinical trials on reperfusion therapy, lytic or percutaneous coronary intervention, and chronic medical treatment with various pharmacological agents have substantially changed the therapeutic approach, decreased in-hospital mortality, and improved the long-term outlook in survivors of the acute phase. New treatments will continue to emerge, but the greatest challenge will be to effectively implement preventive actions in all high-risk individuals and to expand delivery of acute treatment in a timely fashion for all eligible patients.

Angioplasty, Balloon, Coronary↗
PubMed2003

Incremental value of exercise technetium-99m tetrofosmin myocardial perfusion single-photon emission computed tomography for the prediction of cardiac events.

Technetium-99m (Tc-99m) tetrofosmin single-photon emission computed tomography (SPECT) is a useful alternative to thallium-201 scintigraphy for the assessment of myocardial perfusion. This study assessed the incremental value of exercise Tc-99m tetrofosmin SPECT for the prediction of cardiac events in patients with known or suspected coronary artery disease. Exercise Tc-99m tetrofosmin SPECT imaging was performed in 655 consecutive patients. Follow-up was successful in 648 patients (98.9%). Ten patients underwent early coronary revascularization and were excluded. End points were cardiac death, nonfatal infarction, and late (>60 days) coronary revascularization. An abnormal study was defined as the presence of fixed and/or reversible perfusion defects. A summed stress score (SSS) was derived to estimate the extent and severity of perfusion defects. An abnormal scan was detected in 344 patients (54%). During a mean follow-up period of 4 +/- 1.3 years, 56 patients (9%) died (22 cardiac deaths). Nonfatal myocardial infarction occurred in 19 patients (3%), and 89 patients (14%) underwent late coronary revascularization. An abnormal scan was an independent predictor of cardiac death (hazard ratio 3.5, confidence intervals [CI] 1.1 to 12.2) and provided incremental information over clinical and exercise test data (log-likelihood -133 to -125, p <0.05). The SSS provided incremental prognostic information over clinical data as well (log-likelihood -133 to -127, p <0.05) (hazard ratio 1.23, CI 1.10 to 1.38). An abnormal scan (hazard ratio 3.3, CI 1.1 to 12.2)) and the SSS (hazard ratio 1.25, CI 1.07 to 1.45)) were powerful independent predictors of the combined end point of any cardiac event. Thus, exercise Tc-99m tetrofosmin myocardial perfusion SPECT provides information incremental to clinical data for the prediction of cardiac events in patients with known or suspected coronary artery disease.

Aged↗
PubMed2003

Comparison of late outcome in patients with versus without angina pectoris having reversible perfusion abnormalities during dobutamine stress technetium-99m sestamibi single-photon emission computed tomography.

The aim of this study was to assess the prognostic significance of reversible perfusion abnormalities in patients without angina during dobutamine stress technetium-99m sestamibi single-photon emission computed tomography (SPECT). The study comprised 224 patients (age 60 +/- 11 years, 144 men) with completely or partially reversible perfusion abnormalities during dobutamine stress sestamibi SPECT. Follow-up end points were hard cardiac events (cardiac death and nonfatal myocardial infarction). Angina occurred in 93 patients (42%) during the dobutamine stress test (symptomatic ischemia group). The 131 patients without dobutamine-induced angina represented the silent ischemia group. There was no significant difference between patients with and without angina with regard to summed stress perfusion score (5.3 +/- 2.5 vs 5.2 +/- 2.2, p = 0.9) or summed ischemic score (3.1 +/- 1.7 vs 3.2 +/- 1.4, p = 0.7). During a median follow-up of 7.2 years, cardiac death occurred in 14 patients (15%) with and in 21 patients (16%) without angina. Nonfatal myocardial infarction occurred in 8 patients (9%) with and in 13 patients (10%) without angina. In a multivariate analysis model of clinical and perfusion data, independent predictors of cardiac events were age (hazard ratio 1.02, confidence intervals [CI] 1.01 to 1.05 per year increment), diabetes mellitus (hazard ratio 1.9, CI 1.2 to 3.4), and ischemic perfusion score (hazard ratio 2.1, CI 1.3 to 3.8). Patients with silent ischemia defined as reversible perfusion abnormalities without associated angina during dobutamine stress sestamibi SPECT imaging had similar incidences of ischemia and similar cardiac event rates compared with patients with symptomatic ischemia. Therefore, the absence of angina in association with reversible perfusion abnormalities should not be interpreted as a sign of a more benign prognosis.

Angina Pectoris↗
PubMed2003

Hemodynamic response to lower body negative pressure in hemodialysis patients.

BACKGROUND: Hypovolemia is thought to have an important role in the pathogenesis of dialysis-related hypotension. METHODS: We studied the effect of hypovolemia simulated by lower body negative pressure (LBNP) in 11 hypotension-prone (HP) and 11 hypotension-resistant (HR) hemodialysis patients. LBNP was applied stepwise from 0 to -20 to -40 mm Hg. Systolic arterial pressure, heart rate, and central venous pressure (CVP) were recorded continuously after cannulation of the right jugular vein. Stroke volume index was measured at each step echocardiographically. At the end of each level of LBNP, blood samples were obtained to measure norepinephrine (NE), epinephrine (E), and atrial natriuretic peptide (ANP) levels. RESULTS: At baseline, CVP (12 +/- 5 and 16 +/- 7 mm Hg), heart rate (72 +/- 9 and 70 +/- 13 beats/min), cardiac index (2.3 +/- 0.6 and 2.5 +/- 0.9 L/min), NE (median, 341 pg/mL [range,198 to 789 pg/mL] and 365 pg/mL [range, 177 to 675 pg/mL] or 2.02 nmol/L [range, 1.17 to 4.66 nmol/L] and 2.16 nmol/L [range, 1.05 to 4.00 nmol/L]), E (median, 46 pg/mL [range, 18 to 339 pg/mL] and 58 pg/mL [range, 21 to 122 pg/mL] or 251 pmol/L [range, 98 to 1,951 pmol/L] and 317 pmol/L [range, 115 to 666 pmol/L]) were similar, whereas systolic arterial pressure (141 +/- 26 versus 164 +/- 22 mm Hg) and ANP (median, 441 pg/mL [range, 152 to 1,330 pg/mL] versus 804 pg/mL [range, 517 to 3,560 pg/mL] ng/L) were lower (P < 0.05) in HP patients. In response to LBNP (-40 mm Hg), CVP decreased by 6.5 +/- 4.0 mm Hg in the HP group and 4.9 +/- 4.9 mm Hg in the HR group. In HP patients, this decrease was associated with a greater decrease in SI (37% +/- 16% versus 27% +/- 16%) and systolic arterial pressure (19% +/- 21% versus 4% +/- 14%) than in HR patients. Plasma ANP levels did not change, whereas increases in NE and E levels were similar in HP and HR patients. CONCLUSION: Patients who frequently experience episodes of hypotension during dialysis also are prone to develop hypotension during LBNP, which results from reduced myocardial contractile reserve and/or inadequate sympathetic tone.

Aged↗
PubMed2003

Screening for left ventricular dysfunction using a hand-carried cardiac ultrasound device.

BACKGROUND: The hand-carried cardiac ultrasound (HCU) device is a recently introduced imaging device, which may be potentially useful in the primary care setting. AIM: To test the screening potential of a HCU for the detection of left ventricular (LV) dysfunction by evaluating LV ejection fraction (LVEF) and inferior vena cava (IVC) collapse. Standard echocardiographic system (SE) and plasma brain natriuretic peptide (BNP) measurements were used as a reference. METHODS: Eighty-eight consecutive patients (56 male, aged 59+/-12 years) with suspected LV dysfunction were enrolled in the study. The HCU-LVEF was visually estimated and the SE-LVEF was derived by the Simpson's biplane method. A LVEF <40% represented LV dysfunction. An IVC collapse of <50% and BNP levels > or =15 pmol/l were considered abnormal. The correlation of HCU-LVEF, HCU-IVC and BNP to the SE-LVEF and SE-IVC was analysed independently using 2x2 tables. RESULTS: Six patients were excluded because of poor echo images. 19/82 patients had LV dysfunction. The HCU and BNP could identify 17 and 18 out of these 19 patients, respectively. The agreement for LVEF and IVC collapse between SE and HCU was 96% for both parameters. The sensitivity of IVC collapse, HCU-LVEF and BNP in identifying patients with LV dysfunction was 26, 89 and 94%, respectively. CONCLUSION: A HCU device can reliably be used as a screening tool for LV dysfunction.

Echocardiography↗
PubMed2003

Blood pressure is insufficiently controlled in European patients with established coronary heart disease.

BACKGROUND: Elevated blood pressure is associated with an impaired prognosis in patients with established coronary heart disease. Adequate blood pressure control is therefore of utmost importance. We report on two successive European surveys that evaluated whether the goals given in recommendations on secondary prevention are achieved. METHODS: The first European Action on Secondary Prevention through Intervention to Reduce Events (EUROASPIRE I) survey was conducted during 1995-1996 in 21 hospitals in nine European countries. The second survey (EUROASPIRE II) was conducted during 1999-2000 in 47 hospitals (including 20 hospitals that participated in EUROASPIRE I) in 15 Europeans countries. Consecutive patients (aged < 71 years) were identified from hospital records after coronary artery bypass grafting, percutaneous coronary intervention, myocardial infarction, or myocardial ischaemia. Patients were invited for an interview and examination at least 6 months after hospitalization. During the interview, blood pressure was measured in a standardized fashion. Systolic blood pressure >/= 140 mmHg and/or a diastolic blood pressure >/= 90 mmHg were considered as elevated blood pressure. EUROASPIRE II provides a more comprehensive view on the actual management of patients with established coronary disease. Therefore, we decided to concentrate mainly on the EUROASPIRE II data, and to use EUROASPIRE I for the evaluation of time trends. RESULTS: In EUROASPIRE II, 5556 patients were interviewed, and 51% were diagnosed with elevated blood pressure. Large regional variations in the prevalence of elevated blood pressure were observed, with values ranging from 37 to 64%. Twenty-five per cent (1401) of patients were on a diet to reduce blood pressure, and among these 61% had elevated blood pressure. The prevalence of elevated blood pressure among the 4827 (87%) patients taking blood pressure-lowering medication (which was not necessarily taken as an antihypertensive treatment) was 51%. Patients with elevated blood pressure were more likely to be diabetic, hypercholesterolemic, and obese than normotensive patients. The proportion of patients who reported being aware of their hypertensive status was somewhat higher in EUROASPIRE II than in EUROASPIRE I (71 versus 67%), and the use of blood pressure-lowering medication was intensified (91 versus 85%). However, these changes were not accompanied by a decrease in the prevalence of elevated blood pressure (54 versus 55% in centres that participated in both surveys). CONCLUSION: During 1995-2000 the prevalence of elevated blood pressure in patients with established coronary heart disease remained at an unacceptably high level. Throughout Europe, still about half of coronary patients require more intensive blood pressure management.

Aged↗
PubMed2003

Prediction of cardiac death in hypertensive patients with suspected or known coronary artery disease by stress technetium-99m tetrofosmin myocardial perfusion imaging.

BACKGROUND: There are currently insufficient data to indicate a role for stress myocardial perfusion imaging as a prognostic tool in hypertensive patients. OBJECTIVES: To assess the incremental value of stress myocardial perfusion imaging for the prediction of cardiac death in hypertensive patients relative to clinical data. PATIENTS: We studied 601 hypertensive patients (aged 59 +/- 10 years, 387 men) who underwent exercise bicycle or dobutamine (up to 40 microg/kg per min) stress technetium-99m tetrofosmin single photon emission computed tomography (SPECT) for evaluation of coronary artery disease. OUTCOME: Cardiac death during follow-up. RESULTS; An abnormal scan (reversible or fixed perfusion abnormalities) was detected in 293 (49%) patients (134 had reversible abnormalities). During a mean follow-up period of 3.1 +/- 1.3 years, 109 (18%) patients died; of whom, 42 patients (39%) died due to cardiac causes. Independent predictors of cardiac death were age [hazard ratio = 1.04, 95% confidence interval (CI) 1.01-1.08], history of previous myocardial infarction (hazard ratio = 2, CI 1.1-3.7), stress rate-pressure product (hazard ratio = 0.94, CI 0.87-0.98) and abnormal scan (hazard ratio = 4.7 CI 1.9-11.4). Both reversible and fixed abnormalities were predictive of death. The annual cardiac death rate was 5.3% in patients with an abnormal and 0.5% in patients with a normal perfusion scan. CONCLUSION: Stress technetium-99m tetrofosmin myocardial perfusion imaging provides prognostic information incremental to clinical data for the prediction of cardiac death in hypertensive patients with known or suspected coronary artery disease.

Adrenergic beta-Agonists↗
PubMed2003

Prognostic value of dobutamine stress echocardiography in patients with diabetes.

OBJECTIVE: The aim of this study was to assess the incremental value of dobutamine stress echocardiography (DSE) for the risk stratification of diabetic patients who are unable to perform an adequate exercise stress test. Exercise capacity is frequently impaired in patients with diabetes. The role of pharmacologic stress echocardiography in the risk stratification of diabetic patients has not been well defined. RESEARCH DESIGN AND METHODS: We studied 396 diabetic patients (mean age 61 +/- 11 years, 252 men [64%]) with limited exercise capacity who underwent DSE for evaluation of known or suspected coronary artery disease (CAD). End points were hard cardiac events (cardiac death and nonfatal myocardial infarction) and all causes of mortality. RESULTS: During a median follow-up of 3 years, 97 patients (24%) died (55 cardiac deaths), and 27 patients had nonfatal myocardial infarction. In an incremental multivariate analysis model, clinical predictors of hard cardiac events were history of congestive heart failure, previous myocardial infarction, hypercholesterolemia, and ejection fraction at rest. The percentage of ischemic segments was incremental to the clinical model in the prediction of hard cardiac events (chi(2) = 37 vs. 18, P < 0.05). Clinical predictors of all causes of mortality were history of congestive heart failure, age, hypercholesterolemia, and ejection fraction at rest. Wall motion score index at peak stress was incremental to the clinical model in the prediction of mortality (chi(2) = 52 vs. 43, P < 0.05). CONCLUSIONS: DSE provides incremental data for the prediction of mortality and hard cardiac events in patients with diabetes who are unable to perform an adequate exercise stress test.

Adrenergic beta-Agonists↗