Showing papers by "Don Poldermans published in 2000"

The Effect of Bisoprolol on Perioperative Mortality and Myocardial Infarction in High-Risk Patients Undergoing Vascular Surgery

Abstract: A BSTRACT Background Cardiovascular complications are the most important causes of perioperative morbidity and mortality among patients undergoing major vascular surgery. Methods We performed a randomized, multicenter trial to assess the effect of perioperative blockade of beta-adrenergic receptors on the incidence of death from cardiac causes and nonfatal myocardial infarction within 30 days after major vascular surgery in patients at high risk for these events. High-risk patients were identified by the presence of both clinical risk factors and positive results on dobutamine echocardiography. Eligible patients were randomly assigned to receive standard perioperative care or standard care plus perioperative beta-blockade with bisoprolol. Results A total of 1351 patients were screened, and 846 were found to have one or more cardiac risk factors. Of these 846 patients, 173 had positive results on dobutamine echocardiography. Fifty-nine patients were randomly assigned to receive bisoprolol, and 53 to receive standard care. Fifty-three patients were excluded from randomization because they were already taking a beta-blocker, and eight were excluded because they had extensive wall-motion abnormalities either at rest or during stress testing. Two patients in the bisoprolol group died of cardiac causes (3.4 percent), as compared with nine patients in the standard-care group (17 percent, P=0.02). Nonfatal myocardial infarction occurred in nine patients given standard care only (17 percent) and in none of those given standard care plus bisoprolol (P<0.001). Thus, the primary study end point of death from cardiac causes or nonfatal myocardial infarction occurred in 2 patients in the bisoprolol group (3.4 percent) and 18 patients in the standard-care group (34 percent, P<0.001). Conclusions Bisoprolol reduces the perioperative incidence of death from cardiac causes and nonfatal myocardial infarction in high-risk patients who are undergoing major vascular surgery. (N Engl J Med 1999;341:1789-94.)

Does second harmonic imaging improve left ventricular endocardial border identification at higher heart rates during dobutamine stress echocardiography

Abstract: Background: The increased heart rate during dobutamine stress echocardiography (DSE) may impair endocardial border visualization. Second harmonic imaging (SHI) enhances left ventricular (LV) border visualization compared with conventional fundamental imaging (FI) at rest. However, its role during DSE is not well established yet. Objective: Our objective was to compare the additional value of SHI to FI for the LV endocardial border visualization during various stages of DSE. Methods: Eighty patients underwent DSE. Imaging was performed with both FI and SHI at rest and at low-and peak-dose dobutamine infusion. Endocardial border visualization was assessed by using a 16-segment/3-point score (0 = well visualized; 1=poorly visualized; 2=not visualized). Results: Heart rate increased from rest (70 ± 13 bpm) to low-dose dobutamine (77 ± 17, P P P P P P =.0001), whereas the difference was less significant for SHI ( P =.07). Conclusion: Second harmonic imaging improves visualization of the LV endocardial border compared with FI during DSE. The advantage of SHI over FI is more marked at higher heart rates than at rest. (J Am Soc Echocardiogr 2000;13:1019-24.)

Usefulness of the ejection fraction response to dobutamine infusion in predicting functional recovery after coronary artery bypass grafting in patients with left ventricular dysfunction.

Abstract: Quantification of dysfunctional but viable myocardium has high prognostic value for improvement of left ventricular (LV) function after coronary artery bypass grafting (CABG). Dobutamine stress echocardiography (DSE) can assess viable myocardium by segmental wall motion changes during stress. However, analysis of wall motion is subjective with only moderate interinstitutional agreement (70%) and frequently overestimates functional improvement after CABG. In contrast, calculation of ejection fraction (EF) is less subjective and allows a more precise quantification of global contractile reserve. The aim of the study was to compare the prognostic value of EF response and segmental wall motion changes during DSE for the prediction of LV functional recovery after CABG. Forty patients underwent DSE before CABG. EF responses were assessed at rest, low-dose dobutamine, and at peak stress using the biplane disk method. Wall motion was scored using a 16-segment 5-point model. Resting radionuclide ventriculography (RNV-LVEF), performed before and 8 ± 2 months after CABG, was used as an independent reference. Five patients were excluded because of perioperative infarction or poor echo images. In 11 of 35 patients, RNV-LVEF recovered >5%. Improvement in EF during dobutamine infusion predicted RNV-LVEF recovery after CABG significantly better than segmental wall motion changes (72% vs 53%, p = 0.03). A biphasic EF response (i.e., improvement in ≥10% at low dose and subsequent worsening at peak stress) had the highest predictive value (80%) for late functional recovery. In conclusion, EF response to dobutamine infusion was superior to segmental wall motion changes in predicting RNV-LVEF recovery after CABG.