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S Silber

Publications and source records attributed to S Silber.

At least 37 records · Page 2Linked to original sources
PubMed2003

[Detection of coronary calcifications by electron beam tomography and multislice spiral CT: clinical relevance].

Coronary calcifications can be detected and quantified using electron beam tomography (EBT) or newer generation multi-slice spiral CT (MSCT) scanners. An abundance of data has been acquired by EBT. It could be shown that the amount of coronary calcium correlates to the coronary plaque burden. The detection of coronary calcium with CT imaging methods therefore provides a unique opportunity to detect and quantify coronary atherosclerosis in a subclinical stage. Consequently, the presence and amount of coronary calcium has been shown to be indicative for an increased coronary event risk in symptomatic and asymptomatic individuals. Several clinical studies found a predictive value that was superior to conventional risk factors. Clinically, the use of coronary calcification assessment may therefore be beneficial in patients who, based on traditional risk factors, seem to be at "intermediate risk" for coronary events (10-year event risk 10-20%) in order to decide on the aggressiveness of risk factor modification. The role of coronary calcium quantification to monitor the progression of disease has not been clarified yet. Large, ongoing trials will provide further data as to the relative merit of coronary calcium assessment for risk stratification and will help to more clearly define its clinical role. The relationship between coronary calcium and coronary stenoses is more complex. While the absence of coronary calcifications makes significant coronary stenoses unlikely, even large amounts of coronary calcium do not necessarily indicate the presence of coronary artery stenoses. Pronounced coronary calcifications as an isolated finding should therefore not be the motivation for invasive diagnostic procedures in the absence of other evidence of ischemic heart disease.

Calcinosis↗
PubMed2003

A multicentre European registry of intraluminal coronary beta brachytherapy.

AIMS: To assess the feasibility, safety and effectiveness of intravascular brachytherapy (VBT) in routine clinical practice. METHODS AND RESULTS: Between April 1999 and September 2000, 1098 consecutive patients treated in 46 European centres by intraluminal irradiation using a Sr/Y(90)source train (BetaCath, Novoste, GA) were included in a registry, and follow-up data were obtained for 98.8% of them after 6.3+/-2.4 months. Eight hundred and forty (76.5%) patients were males, and mean age was 62.0+/-10.2 years. Two hundred and seventy-one (26.9%) had unstable angina, and 256 (23.5%) were diabetics. Nine hundred and thirteen lesions (77.7%) were the result of in-stent restenosis, 208 (17.7%) were de novo lesions and 48 (4.1%) non-stented restenotic lesions. Mean estimated reference diameter was 3.2+/-0.5mm and mean estimated lesion length was 19.0+/-11.8mm. The prescribed radiation dose was 18.8+/-3.2Gy. Multivessel irradiation was done in 6.2% of cases, and a new stent was implanted in 29.6% of cases. Most patients received 6 or 12 months of combined aspirin and thienopyridin treatment after the procedure. Technical success was obtained in 95.9% of treated lesions, and the in-hospital major adverse cardiac event (MACE) rate was 1.8%. At follow-up, the MACE rate was 18.7% (1.9% deaths from any cause, 2.6% AMI, 13.3% TVR by PCI and 3.3% TVR by CABG). CONCLUSION: The major current application of VBT is the treatment of in-stent restenosis. The good results of VBT observed in recent randomized controlled trials can be reproduced in clinical practice.

Aged↗
PubMed2003

Clinical and angiographic acute and follow up results of intracoronary beta brachytherapy in saphenous vein bypass grafts: a subgroup analysis of the multicentre European registry of intraluminal coronary beta brachytherapy (RENO).

OBJECTIVE: To assess clinically and angiographically the feasibility, safety, and effectiveness of vascular brachytherapy (VBT) in saphenous vein bypass grafts (SVG). PATIENTS AND METHODS: 67 of 1098 (6.1%) consecutive patients of the European registry of intraluminal coronary beta brachytherapy underwent treatment for 68 SVG lesions by VBT using a Sr/Y(90) source train (BetaCath). Clinical follow up data were obtained for all of them after a mean (SD) of 6.3 (2.4) months and angiographic follow up was performed in 61 patients (91.0%) after 6.9 (2.0) months. RESULTS: 58 (86.6%) patients were men, their mean (SD) age was 66 (10) years, 28 (41.8%) had unstable angina, and 21 (31.3%) had diabetes. Fifty three (77.9%) lesions were in-stent restenosis, 13 (19.1%) de novo lesions, and 2 (3.0%) non-stented restenotic lesions. Mean (SD) reference diameter before the intervention was 4.19 (0.52) mm, mean (SD) lesion length was 23.56 (20.38) mm, and mean (SD) minimum lumen diameter measured 0.73 (0.62) mm. Mean (SD) acute gain was 3.02 (0.88) mm. The prescribed radiation dose was 20.1 (3.2) Gy. Pullback manoeuvres were performed in 17 (25.0%) of cases. Most patients received combined aspirin and thienopyridin treatment for 6 or 12 months after the procedure. Technical success was obtained in 62 (91.2%) treated lesions and in-hospital major adverse cardiac events occurred in 4.5%. At follow up, mean (SD) reference diameter was 4.20 (0.53) mm, minimum lumen diameter 2.94 (1.50) mm, and late loss 0.86 (1.25) mm. The overall major adverse cardiac events rate was 26.7%. CONCLUSION: VBT of SVG is feasible and safe. At follow up the reintervention rate and cardiac morbidity and mortality seem to be favourable, considering that interventions in SVG usually are associated with the highest risks.

Aged↗
PubMed2002

Intracoronary beta-radiation to reduce restenosis after balloon angioplasty and stenting; the Beta Radiation In Europe (BRIE) study.

AIMS: The BRIE trial is a registry evaluating the safety and performance of (90)Sr delivered locally (Beta-Cath TM system of Novoste) to de-novo and restenotic lesions in patients with up to two discrete lesions in different vessels. METHODS AND RESULTS: In total, 149 patients (175 lesions) were enrolled; 62 treated with balloons and 113 with stents. The restenosis rate, the minimal luminal diameter and the late loss were determined in three regions of interest: (a) in a subsegment of 5mm containing the original minimal luminal diameter pre-intervention termed target segment; (b) the irradiated segment, 28 mm in length, and (c) the entire analysed segment, 42 mm in length, termed the vessel segment. Binary restenosis was 9.9% for the target segment, 28.9% for the irradiated segment, and 33.6% for the vessel segment. These angiographic results include 5.3% total occlusions. Excluding total occlusions binary restenosis was 4.9%, 25% and 29.9%, respectively. At 1 year the incidence of major adverse cardiac events placed in a hierarchical ranking were: death 2%, myocardial infarction 10.1%, CABG 2%, and target vessel revascularization 20.1%. The event-free survival rate was 65.8%. Non-appropriate coverage of the injured segment by the radioactive source termed geographical miss affected 67.9% of the vessels, and increased edge restenosis significantly (16.3% vs 4.3%, P=0.004). It accounted for 40% of the treatment failures. CONCLUSION: The results of this registry reflect the learning process of the practitioner. The full therapeutic potential of this new technology is reflected by the restenosis rate at the site of the target segment. It can only be unravelled once the incidence of late vessel occlusion and geographical miss has been eliminated by the prolonged use of thienopyridine, the appropriate training of the operator applying this new treatment for restenosis prevention, and the use of longer sources.

Adult↗
PubMed2001

ACC/AHA/ESC Guidelines for the Management of Patients With Atrial Fibrillation: Executive Summary A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines and the European Society of Cardiology Committee for Practice Guidelines and Policy Conferences (Committee to Develop Guidelines for the Management of Patients With Atrial Fibrillation) Developed in Collaboration With the North American Society of Pacing and Electrophysiology.

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Aged↗
PubMed2001

[2d Report on increasing volume of diagnostic and interventional heart catheterization in hospitals and private practice in Germany 1990-1999].

Despite all warnings from the German Ministry of Health, the healthcare insurances and the media, the number of diagnostic (DIAG) and therapeutic (PCI) cardiac catheterizations is continuously growing in hospitals and in private practices. From 1997 to 1999, the number of DIAG increased from 478837 to 561623 and PCI from 135925 to 166132. The average number of DIAG per institution decreased from 1482 in 1997 to 1324 in 1999 and the average number of PCI from 535 to 479. The number of DIAG-performing hospitals increased from 256 to 315 and that of DIAG-performing private practices from 67 to 109. The number of PCI-performing hospitals increased from 211 to 278 and the corresponding private practice locations from 43 to 69. In 1999, 18% of all DIAG and 15% of all PCI in Germany was performed in private practice. Since 1994, the average number of DIAG per private practice continuously decreased as well as the average number of PCI per private practice since 1997. This decrease was more pronounced in private practice (DIAG 378/lab and PCI 111/lab) than in hospitals (DIAG 68/lab and PCI 35/lab). Possible reasons for this trend are an increasing number of low volume centers, a more rigid indication for DIAG and PCI due to quality control programs, and the reduction of reimbursement incentives for social healthcare insured patients in private practice. The real optimal need for DIAG and PCI in Germany, however, has to be determined.

Cardiac Catheterization↗
PubMed2001

[Importance of ECG-triggering with the multi-slice CT for ruling out coronary calcification in individuals without diagnosed coronary disease].

BACKGROUND: To avoid unnecessary cardiac catheterization, ruling out coronary calcification has become increasingly important. On the other hand, the detection of coronary calcification is proof of coronary atherosclerosis and therefore requires a reduction of the LDL-cholesterol < 100 mg/ml according to the NCEP guidelines. The "gold standard" for calcium scanning is traditionally ECG-triggered electron beam tomography (EBT). In addition, mechanical multi-slice CTs (MSCT) have been used without ECG-triggering for more than 6 years for calcium scanning. PATIENTS AND METHODS: The importance of ECG-triggering was assessed by examining apparently healthy subjects referred by their physicians (n = 1,206, 57 +/- 10 years, 75% male) using an Mx-8000 four-slice CT (Marconi, USA). Data were obtained from the MUNICH-Registry (MUltislice Normal Incidence of Coronary Health). Image acquisition without ECG-triggering was performed in spiral mode at 120 kV and 249 mAs using a collimation of 2.5 mm, resulting in an effective slice width of 3.2 mm. Prospective ECG-triggering was achieved in sequential ("axial") mode at 120 kV and 165 mAs using an effective collimation of 2.5 mm. The trigger was set at 333 ms prior to 90% of the expected RR-interval. RESULTS: With both groups well comparable regarding age, sex and risk factors, calcium was ruled out in 51.5% of the individuals without and in 34% of the persons with ECG-triggering (p < 0.001). An Agatston score > 100 was detected in 14.2% without and in 33.1% with ECG-trigger. The loge-transformed calcium scores were 1.7 +/- 2.2 for persons without and 2.9 +/- 2.6 with ECG-trigger (p < 0.001). Multivariate linear regression analysis showed that the application of ECG-triggering was an independent and the strongest predictor for the proof of calcium. With ECG-triggering, calcium was detected in 1.51 +/- 1.42 major coronary arteries (median 1.0), whereas without ECG-triggering, calcium was detected in 1.03 +/- 1.33 major coronary arteries (median 0.0, p < 0.001). CONCLUSION: Since without ECG-triggering every fifth patient with coronary atherosclerosis is erroneously classified as "healthy" and only the sensitive exclusion of coronary calcium is helpful in avoiding unnecessary cardiac catheterizations, the use of ECG-triggering for calcium scanning with MSCT is mandatory.

Aged↗
PubMed2001

ACC/AHA/ESC guidelines for the management of patients with atrial fibrillation: executive summary. A Report of the American College of Cardiology/ American Heart Association Task Force on Practice Guidelines and the European Society of Cardiology Committee for Practice Guidelines and Policy Conferences (Committee to Develop Guidelines for the Management of Patients With Atrial Fibrillation): developed in Collaboration With the North American Society of Pacing and Electrophysiology.

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Algorithms↗
PubMed2001

The AZFc region of the Y chromosome features massive palindromes and uniform recurrent deletions in infertile men.

Deletions of the AZFc (azoospermia factor c) region of the Y chromosome are the most common known cause of spermatogenic failure. We determined the complete nucleotide sequence of AZFc by identifying and distinguishing between near-identical amplicons (massive repeat units) using an iterative mapping-sequencing process. A complex of three palindromes, the largest spanning 3 Mb with 99.97% identity between its arms, encompasses the AZFc region. The palindromes are constructed from six distinct families of amplicons, with unit lengths of 115-678 kb, and may have resulted from tandem duplication and inversion during primate evolution. The palindromic complex contains 11 families of transcription units, all expressed in testis. Deletions of AZFc that cause infertility are remarkably uniform, spanning a 3.5-Mb segment and bounded by 229-kb direct repeats that probably served as substrates for homologous recombination.

Base Sequence↗
PubMed2001

Dedicated asthma center improves the quality of care and resource utilization for pediatric asthma: a multicenter study.

OBJECTIVES: To determine the relative effectiveness of pediatric asthma care among patients treated by a dedicated asthma center (AC) vs children who use the emergency department (ED) as a site of primary asthma care. METHODS: A retrospective case-control design was used. A random sample of AC cases was selected from a designated comprehensive AC over a 12-month period. Concurrent ED control patients were identified from all cases of pediatric asthma from five urban hospitals based on two or more ED visits. Cases and controls were matched (1:2) based on age and National Heart, Lung, and Blood Institute (NHLBI) asthma severity of illness classification. A telephone survey was administered to the caregivers of all enrolled patients in the study sample. RESULTS: Four elements of pediatric asthma care were examined: quality, access, hospital utilization, and functional impact of disease. Demographic data were similar between the ED cases and the AC controls. In terms of quality of care, the AC patients were more likely to use maintenance antiinflammatory medications, 60.2% vs 22.5% (OR = 5.3; 95% CI = 2.9 to 9.7) and more likely to be taking medications at school, 71.4% vs 48.1% (OR = 2.7; 95% CI = 1.5 to 4.7). In terms of access to care, the AC families were more likely to have a physician to call to assist with outpatient management, 98.2% vs 65.0% (OR = 25.3; 95% CI = 9.0 to 76.9). Frequent ED utilization (> or = 1 visit/month) was less likely in the AC patients, 9.2% vs 22.0% (OR = 0.35; 95% CI = 0.16 to 0.79) and school absenteeism was lower as well (9.5 +/- 6.7 days vs 16.6 +/- 10.3, p < 0.001). Additionally, the caregivers of the AC patients missed fewer workdays (4.7 +/- 2.8 vs 7.4 +/- 4.1; p = 0.03). CONCLUSIONS: Significant disparities in quality, access, resource utilization, and functional impact exist between AC and ED patients. Emergency physicians have a unique opportunity to improve the public health by directing ED patients toward pediatric AC treatment.

Absenteeism↗
PubMed2000

[Undertreatment in secondary prevention of patients with coronary heart disease after revascularization].

Coronary artery disease is still the no. 1 killer in the developed countries and must thus be detected and treated at an earlier stage. If coronary artery disease is advanced, patients have to be examined regarding the need for revascularization. For secondary prevention, of course, an optimal change of life style and optimal medical treatment of risk factors is mandatory. Independent of the optimal risk factor modification, all of these patients (according to the rules of evidence-based medicine) should take ASA, statins, beta blockers and ACE-inhibitors, if no contraindications or intolerance are present. Therefore, the problem in secondary prevention is not how to identify these patients, but rather how to fulfill their needs. In our own survey in patients with known coronary artery disease referred for PTCA (including patients with post myocardial infarction previous PTCA or bypass surgery), only 89% were on ASA (or clopidogrel), 51% on lipid lowering drugs (46% on statins), 65% on beta blockers, and only 43% had an ACE-inhibitor (MUNICH data in Figures 1 to 4). The analysis of published literature is also depicted in Figures 1 to 4. Until 1996, patients with known coronary artery disease took ASA in only 26% of the cases but later on it was 77 to 100% (Figure 1). Lipid lowering drugs (especially statins) are prescribed in only 13 to 77% (Figure 2), beta blockers in only 30 to 80% (Figure 3) and ACE-inhibitors in only 10 to 72% (Figure 4). In 2 major studies, a decrease in the rate of intake of these drugs during the follow-up years has been documented. The "ideal tablet" for secondary prevention contains ASA (100 mg), a statin (e.g. for most statins 40 to 80 mg), a beta blocker (e.g. metoprolol 100 mg or bisoprolol 10 mg) and an ACE-inhibitor (e.g. ramipril 10 mg). So this ideal "SPM" ("secondary prevention mix") tablet contains 160 to 300 mg of drugs. In conclusion, the analysis of published data for Europe and the USA shows that--in contrast to the statements of politicians and health care insurance companies--we are not overtreating but rather undertreating our patients regarding medications for secondary prevention.

Adrenergic beta-Antagonists↗
PubMed2000

[Safety and feasibility of intracoronary brachytherapy with the Novoste system within the scope of international multicenter studies].

UNLABELLED: Clinical trials are increasingly investigating the effects of intracoronary radiation for the treatment of de-novo lesions, restenosis (without stents), and in-stent restenosis. As the first group in Germany, we had the opportunity to use the Novoste system within the international multicenter studies BETA-CATH, START and BRIE and report our preliminary experience regarding safety and feasibility of intracoronary brachytherapy with this afterloader. A total of 95 patients were enrolled. The Novoste system was used in 92 patients (104 lesions). Ischemic complications were not observed; therefore, radiation was performed as planned. The mean applied dose was 16 +/- 2 Gy (14-20 Gy, at 2 mm distance) and mean exposure time was 202 +/- 27 s (165-261 s). The addition of brachytherapy increased the total duration of the intervention for 17 +/- 8 min. At the body surface of the patients, the following dose rates were measured: left chest wall: 99 +/- 52 microSv/h; groin 3 +/- 3 microSv/h. All patients received ASS 300 mg/d o.d. Patients with stent implantation in the same session received 250 mg b.i.d. Ticlopidin or 75 mg Clopidogrel o.d. for at least three months. Total mortality and infarct rate was 0. There was no acute, subacute or late stent thrombosis. CONCLUSION: Our first experience with the Novoste Beta-Cath system showed that intracoronary brachytherapy can be safely and simply performed in the cath lab. There were no acute complications. To avoid the possible risk of late stent thrombosis, Ticlopidin or Clopidogrel must be administered for at least three months.

Aged↗