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D Poldermans

Publications and source records attributed to D Poldermans.

At least 109 records · Page 6Linked to original sources
PubMed1998

Myocardial viability: known and unknown.

The assessment of myocardial viability has gained a lot of attention over the past few years. Various imaging techniques, mainly nuclear and echocardiographic approaches, have been developed for this purpose. From the existing data, it has become clear that the presence of dysfunctional yet viable myocardium can predict improvement of regional and global left ventricular (LV) function after revascularization. This issue is most relevant in patients with severely depressed LV function, since in these patients revascularization carries a high (peri-)procedural risk on the one hand, but may substantially improve LV function in some patients. Besides the improvement of resting LV function after revascularization, other end-points may also be clinically relevant, including the response during stress, improvement of exercise capacity, the quality of life and the prevention of LV remodeling. These issues have not been studied extensively thusfar. Finally, several retrospective studies have shown the prognostic value of viability assessment; patients with viable but jeopardized myocardium were significantly more prone to experience cardiac events than patients with viability who underwent revascularization. The different aspects of viability assessment (including pathophysiology, available techniques, current implications and unresolved issues) will be addressed in this manuscript.

Cardiomyopathies↗
PubMed1997

Gender differences in the accuracy of dobutamine stress echocardiography for the diagnosis of coronary artery disease.

The accuracy of dobutamine stress echocardiography (DSE) for the diagnosis of coronary artery disease (CAD) has not been yet evaluated in women. We studied the effect of gender on the accuracy of DSE for the diagnosis of CAD in 306 consecutive patients (210 men and 96 women) with limited exercise capacity and suspected myocardial ischemia who underwent coronary angiography within 3 months of DSE. There were no serious complications during DSE. Men had a higher prevalence of nonsustained ventricular tachycardia (7% vs 0.03%, p <0.05) and supraventricular tachycardia (9% vs 0.03%, p <0.05) during the test compared with women. Peak stress rate-pressure product was not different in men and women (18,140 +/- 4,187 vs 18,543 +/- 4,223). Significant CAD (> or =50% luminal diameter stenosis) was present in 171 men (81%) and in 62 women (65%, p <0.005). The sensitivity, specificity, and accuracy of ischemic pattern at DSE for the diagnosis of significant CAD were 76% (confidence interval [CI] 67 to 84), 94% (CI 89 to 99), and 82% (CI 75 to 90) in women and 73% (CI 67 to 79), 77% (CI 71 to 83), and 74% (CI 68 to 80) in men, respectively. Overall specificity was higher in women than in men (p <0.05). Regional accuracy of DSE was significantly higher in women than in men in the 3 arterial regions (84% [CI 79 to 88] vs 75% [CI 72 to 79], p <0.005). It is concluded that DSE is a safe and feasible method for the diagnosis of CAD in women. The overall specificity and the regional accuracy of DSE are higher in women than in men. Further studies are required to evaluate the functional significance of these findings and their reproducibility in different patient populations.

Cardiotonic Agents↗
PubMed1997

Sustained prognostic value of dobutamine stress echocardiography for late cardiac events after major noncardiac vascular surgery.

BACKGROUND: Late cardiac events after major noncardiac vascular surgery are an important cause of morbidity and mortality. We studied the prognostic value of preoperative dobutamine stress echocardiography, relative to clinical risk assessment, in predicting late cardiac events. METHODS AND RESULTS: Three hundred sixteen patients undergoing major vascular surgery were studied. All patients underwent clinical evaluation for the presence of cardiac risk factors (smoking, hypertension, angina, diabetes, history of heart failure, previous infarction, and age > 70 years) and dobutamine stress echocardiography. Left ventricular wall motion was evaluated at rest, and the extent and severity of stress-induced new wall motion abnormalities were quantified. The heart rate threshold at which new wall motion abnormalities occurred was noted. Patients were followed perioperatively and for 19 +/- 11 months postoperatively, and the occurrence of cardiac events was noted. Univariate and multivariate Cox proportional hazards regression models were used to identify predictors of late cardiac events. Thirty-two cardiac events occurred (11 cardiac deaths, 11 nonfatal myocardial infarctions, and 10 incidents of unstable angina). By multivariate regression analysis, the occurrence of extensive (three or more segments) or limited (one or two segments) stress-induced new wall motion abnormalities and previous infarction independently predicted late cardiac events, elevating the risk by 6.5-, 2.9-, and 3.8-fold, respectively. The severity of ischemia during stress and the heart rate threshold for ischemia were not independently predictive. CONCLUSIONS: Patients with a history of myocardial infarction or stress-induced ischemia have a high risk of fatal and nonfatal cardiac events after vascular surgery. Patients with both a history of infarction and extensive stress-induced ischemia are at especially high risk and deserve intensive management.

Adult↗
PubMed1997

FDG SPECT in the assessment of myocardial viability. Comparison with dobutamine echo.

The use of 18F-fluorodeoxyglucose (FDG) imaging with single photon emission computed tomography (SPECT) has been introduced recently to assess myocardial viability. Several centres have now gained experience with cardiac FDG SPECT imaging, and this report is a summary of the currently available FDG SPECT data. Three studies have compared FDG SPECT with FDG positron emission tomography and demonstrated good agreement between them. Initial results in patients undergoing revascularization suggest that FDG SPECT can predict improvement in contractile function after revascularization. Although the initial results are promising, larger studies are needed to determine the precise role of FDG SPECT in the assessment of myocardial viability.

Cardiotonic Agents↗
PubMed1997

Prognostic value of dobutamine-atropine stress echocardiography for peri-operative and late cardiac events in patients scheduled for vascular surgery.

Cardiac events in the peri-operative phase and late after non-cardiac vascular surgery are a major cause of morbidity and mortality. Numerous tests and diagnostic strategies--usually consisting of a combination of analysis of clinical risk factors and additional non-exercise dependent stress testing, such as thallium scintigraphy, or stress echocardiography--have been developed to preoperatively identify patients with increased risk. The tests ideally should identify three subpopulations in a group with a high prevalence of coronary artery disease; (1) low-risk patients who can be referred for surgery without extra cardiac intervention. (2) patients whose peri-operative cardiac risk outweighs the potential benefits of vascular surgery, (3) patients whose risk may be reduced by peri-operative therapeutic interventions. This review will discuss the prognostic value of dobutamine stress echocardiography for risk stratification in patients scheduled for non-cardiac vascular surgery and discuss guidelines for future management.

Atropine↗
PubMed1997

Hemodynamic changes, plasma catecholamine responses, and echocardiographically detected contractile reserve during two different dobutamine-infusion protocols.

We studied hemodynamic changes, catecholamine responses, and the occurrence of improved wall thickening by echocardiography during two different dobutamine-infusion protocols. Forty-three patients were studied by using a stepwise incremental dobutamine dose-infusion protocol (10-40 microg/kg/min, 3-min intervals); a subgroup of 11 patients also underwent a continuous dobutamine-infusion protocol (10 microg/kg/min for 12 min) in random order. No patient used beta-blockers. At 3-min intervals, blood pressure, heart rate, and plasma concentrations of dobutamine, epinephrine, and norepinephrine were measured. The echocardiographic improvement of wall thickening was analyzed only in paired protocols by visual assessment in left ventricular regions with normal wall motion at rest. The mean heart rate increased in the continuous and stepwise protocols from 73 to 99 and 74 to 132 beats/min. There was no significant change in blood pressure response between the two protocols. The mean plasma dobutamine concentrations during the continuous and stepwise protocols at 0, 3, 6, 9, and 12 min were 0/0; 31/38; 80/203; 106/448; and 120/692 ng/ml, respectively. In each patient, a response curve was constructed for the plasma dobutamine concentration versus heart rate. The heart rate increment and dobutamine concentration at which wall thickening was detected were similar with both protocols (14 +/- 5 vs. 12 +/- 7 beats/min) and (80 +/- 40 vs. 92 +/- 48 ng/ml; mean +/- SD). Wall thickening was noted in two of 11 patients between 0 and 3 min and 11 of 11 patients between 3 and 6 min in both protocols. Catecholamine responses during the continuous and stepwise protocols were epinephrine, 23 versus 28/28 versus 36, and norepinephrine 301 versus 323/347 versus 519. Only norepinephrine plasma concentrations increased significantly during the stepwise protocol. A 6-min dobutamine infusion was sufficient during both protocols to reach an adequate plasma dobutamine concentration, which induced a detectable increase of wall thickening in all patients. There is a significant differences between the two protocols with regard to the plasma catecholamine changes, so some of the hemodynamic effects during the stepwise dobutamine-infusion protocol may be mediated through release of endogenous catecholamines.

Adrenergic beta-Agonists↗
PubMed1997

Doppler tissue imaging in the new era of digital echocardiography.

Doppler tissue imaging is one of the most recent technical achievements of clinical echocardiography. Different Doppler modes are encompassed by Doppler tissue imaging: tissues velocity, pulsed wave-doppler, acceleration, phase, synchronicity and energy modes. With the exception of the energy mode, all modes are based on the Doppler shift, according to the strength of the Doppler signals from the tissues. The most widely used mode is tissue velocity, in which the velocity of moving tissue is calculated in relation to the transducer from the Doppler shift and is displayed as colour-encoded velocity maps in M-mode and two-dimensional imaging formats. Both curved M-mode, applied on two-dimensional images, and three-dimensional reconstruction appear among the most promising applications of velocity mode for the quantitative assessment of regional left ventricular function. A second Doppler mode, pulsed wave-doppler tissue imaging, displays the velocity profile of a region of interest versus time. The velocity data are displayed with a high temporal resolution, but with the disadvantage of a low spatial resolution. A third Doppler mode, tissue acceleration, displays the differences in velocity between subsequent frames in colour-encoded maps. A clinical application has been found in the electrophysiologic field. Other Doppler modes, phase and synchronicity, still require clinical assessment. Lastly, the tissue energy or power mode displays the strength of the Doppler signal from the tissues as gradations of the colour intensity in colour-encoded maps. One of its fields of application appears to be the study of myocardial perfusion with contrast agents. The development of new dedicated algorithms for colour quantification, along with the beginning of the new era of digital echocardiography, should help bring Doppler tissue imaging into the clinical arena.

Echocardiography, Doppler, Color↗
PubMed1997

Detection of myocardial viability with F-18-fluorodeoxyglucose and single photon emission computed tomography.

The application of 18-F-fluorodeoxyglucose (FDG) imaging with single photon emission computed tomography (SPECT) to detect tissue viability has been introduced recently in several centers, both in Europe and the USA. This paper summarizes the available data on FDG SPECT. Three studies have performed a direct comparison between FDG SPECT and FDG PET, showing good agreement between these techniques. Preliminary data in patients with poor left ventricular function undergoing revascularization suggest that FDG SPECT can predict improvement of ventricular function after revascularization. Comparative studies between FDG SPECT and low-dose dobutamine echocardiography also showed close agreement. Although the initial results are promising, larger studies are needed to determine the precise role of FDG SPECT in the assessment of myocardial viability.

Cardiotonic Agents↗
PubMed1995

Cardiac chronotropic responsiveness to beta-adrenoceptor stimulation is not reduced in the elderly.

OBJECTIVES: This study evaluated cardiac beta-adrenoceptor responsiveness in the elderly. BACKGROUND: The hypothesis of reduced cardiac beta-adrenoceptor responsiveness in the elderly is based on a smaller increase in heart rate after administration of isoproterenol, a nonselective beta 1- and beta 2-adrenoceptor agonist. By means of dobutamine-stress-echocardiography we were able to retest the hypothesis more accurately because dobutamine is a relatively selective beta 1-adrenoceptor agonist with weak beta 2- and alpha-adrenoceptor stimulant activity that prevents baroreflex-mediated changes in heart rate. METHODS: After administration of stepwise incremental infusions of dobutamine, we measured heart rate and blood pressure responses in 360 patients who had no beta-adrenergic blocking agent therapy and no side effects during the stress test. For each patient we calculated the dose of dobutamine required to increase heart rate by 50% of the maximal heart rate during the highest dose of dobutamine. RESULTS: No relation was found between age and sensitivity to dobutamine (n = 293). Power analysis revealed that this negative finding was not the result of inadequate sample size. In contrast to the prevailing hypothesis, an increased heart rate response to dobutamine was found even in a subgroup of "healthy" elderly subjects (i.e., those without concomitant disease or acute myocardial ischemia, n = 67) that was not related to changes in blood pressure during stress. However, in subjects with acute ischemia (n = 109), smokers (n = 151) or patients with a history of a previous myocardial infarction (n = 148), dobutamine sensitivity was reduced in the elderly despite a diminished change in systolic blood pressure with advanced age during dobutamine infusion. This phenomenon could be explained by a decrease in efferent cardiac baroreflex sensitivity, as has been observed during acute myocardial ischemia. There were no age-related differences in plasma concentrations of dobutamine. CONCLUSIONS: No evidence for reduced beta-adrenoceptor responsiveness to dobutamine was found in "healthy" elderly subjects.

Aged↗
PubMed1995

Improved cardiac risk stratification in major vascular surgery with dobutamine-atropine stress echocardiography.

OBJECTIVES: This study sought to optimize preoperative cardiac risk stratification in a large group of consecutive candidates for vascular surgery by combining clinical risk assessment and semiquantitative dobutamine-atropine stress echocardiography. BACKGROUND: Dobutamine-atropine stress echocardiography has been used for the prediction of perioperative cardiac risk in a small group of patients scheduled for elective major vascular surgery on the basis of the presence or absence of stress-induced regional left ventricular wall motion abnormalities. METHODS: Clinical risk assessment and dobutamine-atropine stress echocardiography were performed in 302 consecutive patients presenting for major vascular surgery. The extent and severity of stress wall motion abnormalities and the heart rate at which they occurred, in addition to the presence of wall motion abnormalities at rest, were assessed. RESULTS: The absence of clinical risk factors (angina, diabetes, Q waves on the electrocardiogram, symptomatic ventricular tachyarrhythmias, age > 70 years) identified a low risk group of 100 patients with a 1% cardiac event rate (unstable angina). Dobutamine-atropine stress echocardiographic findings were positive in 72 patients. Twenty-seven patients had a perioperative cardiac event (cardiac death in 5, nonfatal infarction in 12, unstable angina pectoris in 10); all 27 patients had positive stress test results (positive predictive value 38%, negative predictive value 100%). The semiquantitative assessment of the extent and severity of ischemia did not provide additional prognostic information in patients with positive test results. In contrast, the heart rate at which ischemia occurred defined a high risk group with a low ischemic threshold (38 patients with 20 events [53%]) and an intermediate risk group with a high ischemic threshold (34 patients with 7 events [21%]). All 5 patients with a fatal outcome and 8 of 12 with a nonfatal myocardial infarction were in the high risk group with a low ischemic threshold. CONCLUSIONS: Clinical variables identify 33% of patients at very low risk for perioperative complications of vascular surgery in whom further testing is redundant. In all other candidates, dobutamine-atropine stress echocardiography is a powerful tool that identifies those patients at intermediate risk and a small group at very high risk. Risk stratification with a combination of clinical assessment and pharmacologic stress echocardiography has the potential to facilitate clinical decision making and conserve resources.

Adult↗
PubMed1994

Safety of dobutamine-atropine stress echocardiography in patients with suspected or proven coronary artery disease.

The purpose of this study was to establish the safety of high-dose dobutamine-atropine stress echocardiography in patients with suspected or proven coronary artery disease. Six hundred fifty consecutive examinations were completed. Mean age of patients was 61 years; 300 had a previous myocardial infarction. Heart rate increased from 73 to 129 beats/min during stress testing, blood pressure did not change significantly (from 140/81 to 150/80 mm Hg). Atropine was added to dobutamine in 239 patients when no ischemia was induced with dobutamine alone and the peak heart rate was < 85% of the theoretical maximal heart rate. Atropine was more frequently administered to patients taking beta blockers (77 vs 27%, p < 0.001). New wall motion abnormalities developed in 243 patients (37%). Significant or symptomatic cardiac tachyarrhythmias, or both, developed during 24 examinations: 1 patient developed ventricular fibrillation, 3 patients developed sustained ventricular tachycardia, 12 patients experienced nonsustained ventricular tachycardia (< 10 beats) and 8 patients had paroxysmal atrial fibrillation. Cardiac arrhythmias were more frequent in patients with a history of ventricular arrhythmias (ventricular tachycardia and fibrillation) (odds ratio 9.9, 2.0 to 45) or left ventricular dysfunction at rest (wall motion score > 1.12) (odds ratio 2.9, 1.1-7.6), but not associated with atropine addition. No death or myocardial infarction occurred. The full dose was not given to 13 patients despite absence of signs or markers of ischemia for limiting side effect, yielding an overall feasibility of the stress test of 98%.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Dobutamine-atropine stress echocardiography and clinical data for predicting late cardiac events in patients with suspected coronary artery disease.

PURPOSE: To compare the relative value of clinical variables with dobutamine-atropine stress echocardiography to predict cardiac events during long-term follow-up. Dobutamine stress echocardiography is increasingly used for the detection of coronary artery disease, but little is known of its prognostic value. PATIENTS AND METHODS: A total of 430 patients (310 men; mean age 61 years, range 22 to 90) were enrolled in the study. Patients were referred for chest pain complaints and were unable to perform an adequate exercise stress test. All patients underwent dobutamine-atropine stress test (incremental dobutamine infusion: 10 to 40 micrograms/kg/minute, continued with atropine 0.25 to 1 mg intravenously if necessary to achieve 85% of the age predicted maximal heart rate, without symptoms or signs of ischemia) and clinical cardiac evaluation. Follow-up was 17 +/- 5 months, with a minimum of 6 months; 3 patients were lost to follow-up. Cardiac events were defined as cardiac death, nonfatal myocardial infarction, and coronary revascularization. RESULTS: Seventy-nine cardiac events occurred in 76 patients: cardiac death (n = 11), nonfatal myocardial infarction (n = 18), and coronary revascularization (n = 50). By multivariate regression analysis, the prognostic value of the stress test in addition to common clinical variables was assessed. (1) Cardiac death was predicted by age greater than 70 years (odds ratio 5.6, 1.5 to 20) or new wall motion abnormalities in a study that is normal at rest (odds ratio 4.1, 1.1 to 15). (2) Death or myocardial infarction was predicted by a history of myocardial infarction (odds ratio 4.8, 1.8 to 13) or age greater than 70 years (odds ratio 2.3, 1.1 to 5.4), and the stress test outcome provided no additional information. (3) If all events were combined, only stress test results were prognostic: new wall motion abnormalities in a study that is normal at rest (odds ratio 3.1, 1.9 to 5.1), wall motion abnormalities at rest (wall motion score at rest > or = 1.12) (odds ratio 2.5, 1.4 to 4.0), or any new wall motion abnormalities during stress (odds ratio 2.0, 1.4 to 3.8). The positive predictive value of any new wall motion abnormality during stress for all late cardiac events was 25% (95% confidence interval [CI] 19 to 31) with a negative predictive value of 87% (95% CI 83 to 91). CONCLUSION: In a large cohort of unselected patients with chest pain syndromes, new wall motion abnormalities induced by dobutamine provide additional information for late cardiac events, independent of clinical variables.

Adult↗
PubMed1994

Dobutamine-atropine stress echocardiography for assessment of perioperative and late cardiac risk in patients undergoing major vascular surgery.

OBJECTIVE: To determine the value of dobutamine-atropine stress echocardiography and clinical variables to predict perioperative and late cardiac events in patients scheduled for elective major non-cardiac vascular surgery. DESIGN: Blinded prospective study. PATIENTS: Patients (n = 187 mean age 69 yrs). MEASUREMENTS: Dobutamine-atropine stress test was performed preoperatively. Results were not used for clinical management. The clinical risk profile was evaluated by Detsky's score. RESULTS: Technically adequate images were obtained in 185/187 patients, one major complication occurred (ventricular fibrillation) and four tests were prematurely stopped due to side effects. Data from 181 patients were analysed. The stress test was positive (new or worsened wall motion abnormality) in 56/181 patients. Perioperative cardiac events were: five fatal myocardial infarctions, three non-fatal myocardial infarctions, nine unstable angina pectoris and one pulmonary edema. All patients with a cardiac event had a positive stress test (18/56). No event occurred in patients with a negative stress test. By multivariate analysis only a new wall motion abnormality during the stress test (odds ratio 45.0, 6-369) was a significant predictor of cardiac events. Patients (n = 154) were followed after operation for 16 +/- 9 months. Twenty-four cardiac events occurred in 21 patients: six fatal myocardial infarctions, three non-fatal myocardial infarctions, six unstable angina pectoris, three ventricular arrhythmias and six congestive heart failures. The stress echo was positive in 19/21 patients with late cardiac events. The cardiac events correlated by multivariate analysis with a history of myocardial infarction (odds ratio 9.6, 1.9-47.7) and new wall motion abnormalities (odds ratio 6.2, 1.5-25.1). CONCLUSION: Dobutamine-atropine stress echocardiography is a relatively safe and useful test to identify patients at risk of perioperative and late postoperative cardiac events.

Aged↗
PubMed1994

Atropine increases the accuracy of dobutamine stress echocardiography in patients taking beta-blockers.

Dobutamine-atropine stress echocardiography is used for the non-invasive diagnosis of coronary artery disease, but stress test results may be influenced by beta-blockers. The aim of this study was to assess if the addition of atropine can compensate for the presence of beta-blockers in dobutamine stress echocardiography. Twenty-six patients referred for evaluation of chest pain were studied twice, on and off metoprolol 100 mg b.i.d. (in random order sequence) with a wash-out period of at least 48 h. Dobutamine stress echocardiography was performed using up to 40 micrograms.kg-1.min-1, followed, if necessary, by the addition of atropine to achieve 85% of the age-predicted maximal heart rate, unless symptoms or markers of ischaemia appeared. Atropine was given to patients on beta-blockers more often [(22/26) vs (6/26)] than to those off beta-blockers (P < 0.001). Heart rate at every stage of the test was lower on beta-blockers. Chest pain occurred in patients on beta-blockers significantly less than in those off beta-blockers (8% vs 46%), and the addition of atropine made no significant difference (31% vs 46%). During dobutamine stress, new wall motion abnormalities occurred in three patients on beta-blockers (12%); this number increased to 15 after the addition of atropine (57%). New or worsened wall motion abnormalities occurred in 12 patients (46%) off beta-blockers with dobutamine alone and in 14 patients after adding atropine (53%).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1994

[Stress echocardiography: 4 years of experience at the Thoraxcenter].

In this article, we report the experience on stress echocardiography at the Thoraxcenter of Erasmus University of Rotterdam in the years 1990-1994. Different types of stress have been used in conjunction with ultrasound techniques. The results have been compared with other non-invasive methods (exercise ECG testing, myocardial perfusion scintigraphy with single photon emission computed tomography) and with coronary arteriography. Both the diagnostic and prognostic value of stress echocardiography have been assessed in different clinical situations, as in patients with chest pain and suspected or proven coronary artery disease, patients referred for percutaneous transluminal coronary angioplasty, patients referred for major non cardiac vascular surgery. After this period of validation, stress echocardiography has now a definite role in the clinical decision making for the evaluation of myocardial ischemia. The assessment of viable myocardium, especially in patients with advanced left ventricular dysfunction, is one of the major topic currently under investigation. Practical aspects of the interpretation of the tests, costs and organization of the stress echo laboratory, indications and newest research applications are also discussed.

Angioplasty, Balloon, Coronary↗