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Bernhard Meier

Publications and source records attributed to Bernhard Meier.

At least 19 recordsLinked to original sources

Early exercise after coronary stenting is safe.

OBJECTIVES: In this study, we sought to assess safety of symptom-limited exercise stress tests the day after coronary stenting. BACKGROUND: Isolated cases of coronary stent thrombosis have been linked to early exercise stress testing, thereby questioning the safety of unrestricted physical activity after the coronary procedure. METHODS: At a single center, 1,000 patients were randomized to a symptom-limited stress test the day after coronary stenting or no stress test. The antiplatelet regimen consisted of acetylsalicylic acid and postprocedural ticlopidine or clopidogrel. The primary end point of the study was the incidence of clinical stent thrombosis at 14 days. The secondary end point was the occurrence of access site complications. RESULTS: Clinical stent thrombosis occurred in five patients (1%) undergoing stress test and in five patients (1%) randomized to no stress test (p = 1.0). Access site complications were detected in 4% and 5.2% of cases, respectively (p = 0.37). CONCLUSIONS: Symptom-limited exercise stress testing the day after coronary stenting does not increase the risk of clinical stent thrombosis or access site complications. Further investigations on safety of early vigorous exercise after coronary stenting in a non-supervised setting are warranted.

Aged↗

Effect of abciximab versus tirofiban on activated clotting time during percutaneous intervention and its relation to clinical outcomes--observations from the TARGET trial.

Previous evidence suggests that the monoclonal antibody abciximab may have a more potent anticoagulant effect than small-molecule glycoprotein (GP) IIb/IIIa inhibitors. We prospectively reviewed collected heparin dose, activated clotting time (ACT), and corresponding clinical outcome data from The Do Tirofiban and ReoPro Give Similar Efficacy Outcome Trial (TARGET), a direct comparison of tirofiban versus abciximab in patients who underwent percutaneous intervention. Of the 4,809 patients enrolled in the trial, 3,739 patients (78%) had an ACT measured after the administration of GP IIb/IIIa and heparin (peak procedural ACT); this formed the population for the present study. Mean total heparin dose was 75 +/- 32 and 76 +/- 31 U/kg in the tirofiban and abciximab groups, respectively. The resultant mean peak ACTs were 296 +/- 91 and 299 +/- 89 seconds (p = 0.09). In a subset of patients with both baseline ACT (before any heparin or GP IIb/IIIa therapy) and peak procedural ACT measurements, the difference in ACT between these time points was 80 +/- 97 vs 82 +/- 101 seconds (p = 0.44) for the tirofiban and abciximab groups, respectively. After adjusting for patients' weight, weight-adjusted heparin dose, and method of ACT measurement in a multiple linear regression analysis, the type of GP IIb/IIIa inhibitor was not predictive of the peak ACT (p = 0.24). When stratified by ACT quartile, no statistically significant difference in bleeding or ischemic end points between the tirofiban and abciximab cohorts was observed. In this large contemporary percutaneous coronary intervention trial, there was no observed difference in the anticoagulant effect of tirofiban and abciximab, as measured by the ACT, or in the incidence of bleeding or ischemic complications in each ACT quartile.

Abciximab↗

Is there functional collateral flow during vascular occlusion in angiographically normal coronary arteries?

BACKGROUND: Thus far, it is unknown whether there is functional collateral flow through preexisting anastomoses in patients with angiographically normal coronary arteries. Such preformed coronary collateral vessels could form the basis for subsequently developing protective natural bypasses in the presence of coronary artery disease. METHODS AND RESULTS: Among 100 patients, the collateral flow index (CFI) was measured in coronary arteries without stenotic lesions. The CFI was determined by simultaneous measurement of mean aortic pressure, central venous pressure, and coronary wedge pressure via a sensor-tipped guidewire at the end of a 1-minute balloon occlusion. Patients were divided in 2 groups according to complete angiographic absence (51 patients) or partial presence (49 patients) of stenotic lesions in coronary arteries other than that undergoing collateral measurement. CFI in all patients (61+/-10 years; men/women, 69/31) amounted to 0.18+/-0.08 (range, 0.04 to 0.36). It showed a normal Gaussian frequency distribution; 22 individuals had a CFI > or =0.25, a value that was empirically found to represent well-developed collaterals protective against myocardial ischemia during coronary occlusion. Accordingly, 17 patients did not reveal signs of myocardial ischemia during coronary balloon occlusion, as assessed from an intracoronary ECG, and 26 patients did not experience angina pectoris during occlusion. CONCLUSIONS: In humans with angiographically normal coronary arteries, there are functional collateral vessels to the extent that one fifth to one quarter of them do not show signs of myocardial ischemia during brief vascular occlusions.

Angioplasty, Balloon, Coronary↗

Low pro-brain natriuretic peptide levels predict benign clinical outcome in acute pulmonary embolism.

BACKGROUND: The role of pro-brain natriuretic peptide (proBNP) for the prediction of clinical outcome has not been examined in patients with acute pulmonary embolism (PE). METHODS AND RESULTS: ProBNP levels were measured in 73 patients with acute PE within 4 hours of admission. Adverse clinical outcome was defined as in-hospital death or the need for at least 1 of the following: cardiopulmonary resuscitation, mechanical ventilation, pressors, thrombolysis, catheter fragmentation, or surgical embolectomy. In the 53 patients with a benign clinical outcome, proBNP (median 121, range 16 to 34 802 pg/mL) was lower than in 20 patients with adverse clinical outcome (median 4250, range 92 to 49 607 pg/mL; P<0.0001). The negative predictive value of proBNP levels <500 pg/mL to predict adverse clinical outcome was 97% (95% confidence interval 84 to 99). ProBNP remained an independent predictor for adverse clinical outcome (odds ratio 14.6; 95% confidence interval 1.5 to 139.0; P=0.02) after adjusting for severity of PE (submassive/massive), troponin T levels >0.01 ng/mL, age >70 years, gender, and history of congestive heart failure. CONCLUSIONS: Low proBNP levels predict an uneventful hospital course in patients with acute PE. A proBNP level <500 pg/mL identifies patients who will be potential candidates for an abbreviated hospital length of stay or care on a completely outpatient basis.

Acute Disease↗

Four French catheters for diagnostic coronary angiography.

A randomized study was conducted to assess the feasibility of 4 Fr catheters for diagnostic coronary angiograms. A total of 1,114 consecutive patients were randomized to 4 or 5 Fr catheters. Ease of use of catheters was subjectively assessed by the primary operator and the picture quality was assessed by two independent observers with a good interobserver variability (r = 0.94; P < 0.001). Predischarge local complications were recorded by the attending physician. No statistically significant difference was observed in the picture quality for the left coronary artery, right coronary artery, aorta, left ventricle, venous grafts, or renal arteries between the two groups. Fluoroscopy time (7.1 +/- 5.6 for 4 Fr vs. 6.7 +/- 5.7 min for 5 Fr) and contrast quantity (140 +/- 58 vs. 144 +/- 57 ml) were comparable between the two groups. There was a statistically significant difference in favor of the 5 Fr group as regards maneuverability of catheters (93% vs. 79%; P < 0.001), and 5 Fr pigtail catheters crossed the aortic valve easier than the 4 Fr pigtail catheters (91% vs. 81%; P < 0.001). Crossover to the other catheter size or a larger sheath was more frequent with 4 Fr catheters (33/522 vs. 3/592; P < 0.001). Median time to hemostasis was 9 min for 4 Fr and 14 min for 5 Fr (P < 0.001). Of the 4 Fr patients, 84% could be mobilized at 1 hr and 86% of 5 Fr patients at 2 hr. Significant hematomas were observed in 2% with 4 Fr or 5 Fr and small hematomas in 10% and 16%, respectively (P = NS). Time to discharge was comparable in both groups (4.0 +/- 3.2 with 4 Fr vs. 4.3 +/- 3.7 hr with 5 Fr). The 4 Fr catheters are a good alternative for diagnostic coronary angiograms. The increased difficulty in maneuverability and a need for catheter changes in 70% are compensated for in part by easier hemostasis. With increasing use and finesse of these catheters, the difficulty in maneuverability are likely to be overcome.

Aged↗

Successful repositioning of an Amplatzer duct occluder immediately after inadvertent embolization in the descending aorta.

A case is described of the inadvertent embolization of an Amplatzer duct occluder in the descending aorta in a 10-year-old girl. It was possible to snare the device and bring it in its normal position in the aortic ductus ampulla. With a second snare, the recessed screw of the device could be caught and the device was successfully pulled back into the ductus.

Aorta, Thoracic↗

Pacman sign during device closure of the patent foramen ovale.

The Pacman Sign during devise closure of the patent foramen ovale refers to the aspect of the device on fluoroscopy that should be achieved before release. In an orthograde view, the cranial halves of the left and right atrial disks should appear like open jaws biting into the thick septum secundum reminding of arcade game figure Pacman about to gobble up a dot.

Adult↗

Transcatheter left atrial appendage occlusion with Amplatzer devices to obviate anticoagulation in patients with atrial fibrillation.

It is assumed that over 90% of clinically apparent embolisms in atrial fibrillation originate from the left atrial appendage. Recently, a percutaneous method (PLAATO technique) to occlude the left atrial appendage to the end of preventing thromboembolic complications of atrial fibrillation has been introduced into clinical practice. This technique is quite intricate and requires general anesthesia. The Amplatzer atrial septal occluder lends itself for a more simple approach to this intervention. The first 16 patients treated at four centers are described. Their age varied from 58 to 83 years. All suffered from atrial fibrillation but eight of them were in sinus rhythm at the time of implantation. All but two procedures were done under local anesthesia of the groin only. There was one technical failure (device embolization) requiring surgery. All other patients left the hospital a day after the procedure without complications. There were no problems or embolic events during an overall follow-up of 5 patient-years and all left atrial appendages were completely occluded without evidence of thrombosis at the atrial side of the device at the latest follow-up echocardiography. With the Amplatzer technique, the left atrial appendage can be percutaneously occluded with a venous puncture under local anesthesia, without echocardiographic guidance, and at a reasonable risk. It remains to be evaluated in larger series or randomized trials how the simpler Amplatzer technique compares with the complex PLAATO technique, and whether left atrial appendage closure is competitive with oral anticoagulation with warfarin or the novel ximelagatran to prevent thromboembolism in atrial fibrillation.

Aged↗

Pitfalls and key lessons with the symmetry proximal anastomotic device in coronary artery bypass surgery.

BACKGROUND: Increasing practice of less-invasive coronary artery bypass surgery has generated a revival of automated methods to facilitate the creation of vascular connections during coronary artery bypass grafting procedures. METHODS: We have reviewed our clinical experience with 107 patients who received at least one proximal Symmetry aortic connector from St. Jude Medical Anastomotic Technology Group (St. Paul, MN) to connect a saphenous vein graft to the ascending aorta, in whom the minimal follow-up is 6 months. Seventy-five patients were part of an observational study, and 32 patients were enrolled in a prospective randomized study to compare the anastomotic device with the conventional suture technique. Key lessons and pitfalls observed during loading and deployment as well angiographic findings are presented. RESULTS: Hospital mortality was 0.9% (1/107); a 76-year-old woman suffered from cerebral complications and died after combined coronary artery bypass grafting and aortic valve replacement. Two connectors had to be removed because of leakage and one because of incomplete deployment. The residual 104 grafts connected to the ascending aorta were patent at the end of the operation (mean flow, 72 +/- 29 mL/min). Fourteen patients from the prospective study have received 6 months of angiographic assessment so far. Forty-two grafts have been evaluated: all IMA grafts (n = 14) are patent. Four radial artery grafts have been studied: three are patent and one is occluded. Twenty-four vein grafts have been assessed: 11 were hand-sewn and 13 were connected to the aorta with the proximal connector system. Patency rate is not different between the two techniques, but there is an incidence of 38% (5/13) stenosis in the proximal vein graft segment in those patients with a proximal connector. No proximal hand-sewn anastomosis shows any significant stenosis. CONCLUSIONS: The use of proximal devices allows ultrafast connection of a bypass graft to the aorta. The handling of this device is simple, manipulations on the ascending aorta are minimized, and hemostasis is perfect. However, because stenoses have been observed in the vein graft close to the connector site, mid- and long-term patency rates have to be assessed in large prospective trials.

Anastomosis, Surgical↗

Interventional cardiology in Europe 1999.

AIMS: The purpose of this registry is to collect data on trends in interventional cardiology within Europe. Special interest focuses on relative increases and ratios in newer revascularization approaches and its distribution in different regions in Europe. METHODS AND RESULTS: Questionnaires distributed to delegates of the national societies of cardiology represented in the European Society of Cardiology to be completed by local institutions and operators yielded that 1,452,751 angiograms and 452,019 PTCAs were performed in 1999. This is an increase of 28% and 16%, respectively, compared with 1998. Most of these increases are due to high relative increases in eastern European countries. The number of PTCAs per 106 inhabitants rose to 714 in 1999. Coronary stenting increased by 31% to about 313,000 stents implanted in 1999. Complication rates remained stable, the need for emergency coronary artery bypass grafting showing a further slight decrease to currently 0.3%. CONCLUSION: Interventional cardiology in Europe is still growing, mainly due to rapid growth in countries with lower socio-economical levels. In some central European countries a saturation seemed to be reached with only minor increases in procedures performed. Coronary stenting remains the only noteworthy and growing complement or alternative to balloon angioplasty.

Angioplasty, Balloon, Coronary↗

Incremental prognostic value of troponin I and echocardiography in patients with acute pulmonary embolism.

BACKGROUND: To test the hypothesis that troponin I and echocardiography have an incremental prognostic value in patients with pulmonary embolism (PE). METHODS AND RESULTS: In 91 patients with acute PE, echocardiography was performed within 4h of admission. Troponin I levels were obtained on admission and 12h thereafter. The 0.06 microg/l troponin I cut-off level was identified as the most useful, high-sensitivity cut-off level for the prediction of adverse outcome by receiver operating characteristic analysis with a sensitivity and specificity of 86%, respectively. Twenty-eight (31%) patients had elevated troponin I levels (4.9+/-3.8 microg/l). Twenty-one (23%) patients had adverse clinical outcomes including in-hospital death in five, cardiopulmonary resuscitation in four, mechanical ventilation in six, pressors in 14, thrombolysis in 14, catheter fragmentation in three, and surgical embolectomy in three. The area under the receiver operating characteristic curve from multivariate regression models for predicting adverse outcome without troponin I and echocardiography (0.765), with troponin I (0.890) or echocardiography alone (0.858), and the combination of both tests (0.900) was incremental. Three-month survival rate was highest in patients with both a normal troponin I level and a normal echocardiogram (98%). Positive predictive value for adverse clinical outcomes of the combination of echocardiography and troponin I was higher (75% (95%CI 55-88%)) compared with each test alone (echocardiography: 41%, 95% CI 28-56%; troponin I: 64%, 95% CI 46-79%). CONCLUSIONS: While troponin I measurements added most of the prognostic information for identifying high-risk patients, a normal echocardiogram combined with a negative troponin I level was most useful to identify patients at lowest risk for early death.

Acute Disease↗

Exercise-induced human coronary collateral function: quantitative assessment during acute coronary occlusions.

In 50 patients undergoing percutaneous transluminal coronary angioplasty because of chronic angina pectoris, a collateral flow index (CFI) was determined at the start and the end of two 1-min coronary occlusions, randomly accompanied by a resting state or a 3-min dynamic handgrip exercise (DHE). CFI expressing collateral flow relative to normal antegrade flow was determined by simultaneous coronary occlusive pressure, mean aortic pressure and central venous pressure measurements. When comparing CFI without and with DHE at the start as well as at the end of balloon occlusions, a significant increase was observed with DHE (overall p < 0.0001); start: 0.18 +/- 0.12 vs. 0.22 +/- 0.13, respectively (p = 0.01); end of occlusion: 0.21 +/- 0.14 vs. 0.25 +/- 0.14, respectively (p = 0.007).

Acute Disease↗

Sirolimus eluting stent: a new era in interventional cardiology?

Coronary artery stents have emerged as the preferred tool for percutaneous coronary interventions during the past decade by eliminating abrupt vessel closure and reducing restenosis compared with balloon angioplasty. While coronary artery stents prevent constrictive arterial remodeling and elastic recoil, the implantation is associated with more severe arterial vascular injury than balloon angioplasty alone. The arterial injury initiates a vasculoproliferative response with smooth muscle cell proliferation and migration as well as extracellular matrix formation, which may lead to severe neointimal hyperplasia with in-stent restenosis in 10-30% of cases. Sirolimus, a naturally occurring macrocyclic lactone, has been identified as a pharmacological cell cycle inhibitor with potent antiproliferative and antimigratory effects on vascular smooth muscle cells in vitro. The systemic administration of sirolimus has been shown to effectively reduce neointimal hyperplasia in experimental restenosis models. Subsequently, sirolimus has been incorporated at therapeutically important doses into biocompatible polymers, which made it suitable for stent-based drug elution. Investigation of sirolimus eluting stents in both experimental and clinical restenosis studies have demonstrated dramatic reductions in neointimal hyperplasia. Accordingly, sirolimus eluting stents offer an attractive mode of local drug delivery by minimizing systemic toxicity and maximizing local dose requirements. In addition, sirolimus eluting stents hold great promise to effectively prevent restenosis.

Angioplasty, Balloon, Coronary↗

The smaller they come.

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Angioplasty, Balloon, Coronary↗