[Heart catheter in angina pectoris: must we set stricter indications?].
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Publications and source records attributed to Sigmund Silber.
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BACKGROUND AND PURPOSE: The primary care sector is of key importance for the management of patients with diabetes mellitus. The authors investigated (a) the prevalence of diabetes mellitus type 1 and type 2, (b) the type and frequency of non-drug and drug treatment and its association with the presence of diabetic complications, and (c) the quality of metabolic control by HbA1c. METHODS: Using a nationwide probability sample of 3,188 general practices (response rate [RR] 50.6%), a total of 55,518 (RR 93.5%) patients were assessed in a prospective cross-sectional study by their physicians in September 2003 in a standardized manner using questionnaires, physician interview, and laboratory assessments. In addition to diabetes mellitus, 28 diseases were explicitly screened for, among them typical macrovascular (coronary heart disease, cerebrovascular disease, peripheral arterial disease) and microvascular disease (neuropathy, nephropathy, retinopathy, diabetic foot) complications. RESULTS: The prevalence of diabetes mellitus was 0.5% (type 1) and 14.7% (type 2), respectively. 49.5% (type 1) and 50.2% (type 2) of patients had micro- or macrovascular complications. 6.8% did not receive any treatment, 13.5% received non-drug treatment, and 75.3% received oral antidiabetic drugs and/or insulin (26.6% a combination of two or more). Compared to diabetics without any complications, treatment intensity was significantly higher in patients with microvascular complications (odds ratio [OR] 3.02), but not in those with macrovascular complications only (OR 0.98). An HbA1c value>or=7.0% was recorded in 39.6% of patients. CONCLUSION: Compared to previous studies in this setting, the proportion of diabetics with drug treatment has increased. More patients receive antidiabetic drug combinations. Quality of blood sugar control appears to have improved as well.
AIMS: The DETECT study was performed to obtain representative data about the frequency, distribution, and treatment of patients with coronary artery disease (CAD) in the primary care setting in Germany. METHODS AND RESULTS: The DETECT study was a cross-sectional clinical- epidemiological survey of a nationally representative sample of 3795 primary care offices and 55,518 patients. Overall, 12.4% of patients were diagnosed with CAD. Stable angina pectoris and myocardial infarction were the most frequent (4.2%) subgroups, followed by status post (s/p) percutaneous coronary interventions (PCI, 3.0%) and s/p coronary bypass surgery (2.2%). Patients with CAD were prescribed AT1 receptor antagonists (in 19.4% of cases), beta blockers (57.2%), ACE inhibitors (49.9%), antiplatelet agents (52.7%), statins (43.0%), and long-term nitrates (24.5%). When comparing all CAD patients with social health care insurance to those who had private insurance, private patients had significantly higher rates of revascularisation procedures and use of preventive medications. CONCLUSION: Great potential remains for improving secondary prevention in primary care in Germany to reduce the risk of further coronary or vascular events, especially in patients with social health care insurance.
The European Society of Cardiology (ESC) for the first time issued guidelines for percutaneous coronary interventions (PCI) in spring 2005. The strengths of recommendations stated in the ESC guidelines (as in those of the AHA/ACC [American Heart Association/American College of Cardiology]) are traditionally a combination of recommendation classes (I, IIa, and IIb) and a level of evidence (A, B, or C). This paper explains and discusses selected focal points of the ESC PCI guidelines based on three representative cases from daily practice. 1. Stable coronary artery disease (CAD): PCI in a 53-year-old patient without angina pectoris and proof of myocardial ischemia. With a clear indication of ischemia in the anterior myocardial wall, the ESC PCI guidelines indicated coronary angiography with possible PCI, even without angina pectoris symptoms. Cardiac catheterization showed a 99% proximal LAD stenosis, which was immediately dilated and stented based on the indicated ischemia. According to the ESC PCI guidelines, an intervention is indicated for CAD when a larger ischemic area is clearly evident even in the absence of typical angina (recommendation class I A). 2. ST segment elevation myocardial infarction (STEMI): PCI even after successful thrombolysis. A 70-year-old patient experienced acute substernal pain and immediately went to his nearby hospital. The ECG clearly showed anterior myocardial wall STEMI, which in this hospital without a cardiac cath lab indicated thrombolysis, since it could be initiated within 3 h after the onset of chest pain. Pain relief was evident soon after thrombolysis, combined with a resolution of the ST segment elevations. As suggested by the ESC PCI guidelines, a transfer to a cardiac cath lab took place the next day, where the 50% residual stenosis of the LAD was stented. The ESC PCI guidelines suggest coronary angiography with possible PCI within 1-2 days following successful thrombolysis (recommendation class I A). Thus, even "successful" thrombolysis is not regarded as the final treatment for STEMI. 3. Premature termination of clopidogrel after stent implantation: stent thrombosis with acute myocardial infarction. A 46-year-old patient visited the practice due to increasing dyspnea. 4 months earlier, a Taxus stent had been implanted at a heart center into the second RPLS of the RCX; 3 days later, a Cypher stent was implanted in the LAD. Upon being discharged on a Friday at noon, the patient was advised to see his general practitioner soon to attain a prescription for clopidogrel. The patient was given an appointment at his general practitioner for the following Wednesday afternoon. But on that Wednesday morning the patient went into cardiogenic shock. Although the occluded LAD (stent thrombosis) could be quickly reopened, left ventricular myocardium became severely damaged. Until a cardiac transplantation will be performed, a defibrillator was implanted. This "organizational" gap in clopidogrel administration did not conform to the ESC PCI guidelines: after implantation of any coronary stent, dual antiplatelet treatment (acetylsalicylic acid and clopidogrel) must be consistently administered for at least 4 weeks. After implantation of drug-eluting stents (DES), the ESC PCI guidelines call for clopidogrel administration for at least 6 months; when small vessels, long lesions or a complex anatomy (e. g., bifurcation stenting) are involved, a duration of 1 year or even longer is recommended. The optimal duration of platelet aggregation inhibition following PCI with DES of unprotected left main stem stenoses is unknown at this time. The traditional levels of evidence according to ESC, AHA and ACC criteria (levels A, B, or C) do no longer meet the actual requirements to assess the scientific evidence of randomized PCI trials and registry studies. For example, only two small randomized studies with few patients and insufficient statistical power utilizing a clinically insignificant surrogate endpoint would be enough to attain level of evidence A. Consequently, a new scoring system will be proposed, which considers criteria such as the importance of a primary clinical endpoint, the statistical power achieved, and the presence of an independent external data review and safety monitoring board.
BACKGROUND: Preclinical data suggest beneficial effects of angiotensin II receptor blockers (ARBs) on neointima formation after vascular injury. Preliminary clinical data, however, revealed conflicting results. The AACHEN trial was a double-blind, randomized, placebo-controlled clinical multicenter trial to evaluate the effects of candesartan cilexetil on intimal hyperplasia after coronary stent implantation. METHODS: A total of 120 patients (61 +/- 9 years, 83% male) were randomized to receive either 32 mg candesartan cilexetil (active) or placebo starting 7 to 14 days before elective coronary stent implantation. A follow-up angiography including intravascular ultrasound assessment of the target lesion was performed 24 +/- 2 weeks after stent implantation. The primary end point was defined as the difference in neointimal area between groups as assessed by intravascular ultrasound. Secondary end points included differences in angiographic parameters (ie, restenosis rate) and incidence of major cardiac events. RESULTS: The mean stent length measured 15.0 +/- 4.9 mm in the active and 14.6 +/- 5.7 mm in the placebo group (P = .81). There was no significant difference in neointimal area between groups (2.1 +/- 1.0 vs 2.1 +/- 1.5 mm2, P = 1.00), nor were there differences in angiographic end point parameters. Major cardiac event rates were not significantly different between treatment groups (8% vs 11%, P = .75). CONCLUSIONS: High-dose candesartan cilexetil therapy in patients with symptomatic coronary artery disease undergoing coronary stent implantation does not reduce clinical event rates, restenosis rates, or neointimal proliferation after elective stent implantation.
Guidelines are based on a scientific analysis from existing data of randomized controlled trials (RCTs), registry trials, simple registries, case reports, and the personal experience of the task force members. Furthermore, meta-analyses and subgroup analyses are used to derive the strengths of recommendations. Fortunately, the major cardiac societies, i.e., the American College of Cardiology (ACC), the American Heart Association (AHA), and the European Society of Cardiology (ESC), are essentially using the same definitions for the levels of recommendations. In the expanding field of cardiology, however, the overwhelming and increasing number of clinical studies reveals the limitations of the traditional ranking of these studies: Applying the standard definitions of the ACC/AHA/ESC criteria for the levels of recommendation, almost every PCI procedure would easily reach the level of evidence A, even with two small, underpowered studies and a surrogate endpoint. Although meta-analyses are important tools for creating an overview of major diagnostic or treatment modalities, they are bound to severe limitations. The compilation of several underpowered, small trials can generate a statistically artificial "significant" result. This is especially important because only two meta-analyses containing almost identical studies could easily yield an evidence level A. RCTs are usually designed and conducted according to a power calculation, for which a primary clinical or surrogate endpoint can be chosen. Surrogate endpoints, however, do not necessarily correlate with the clinical outcome. The history of medicine is full of errors introduced by underpowered studies with surrogate endpoints. Many investigators and companies attempt to tease out treatment effects in specific subpopulations of patients. These subgroup analyses are usually underpowered. Another major limitation of the ACC/AHA/ESC scoring system is that neither the power of a study nor the choice of a primary clinical endpoint is included in their definitions. Yet another limitation of the ACC/AHA/ESC grading system is that two "simple" registries may already lead to a level of evidence B. A new scoring system is presented addressing most of these limitations: a primary clinical endpoint receives three points, whereas all of the following receive one point: double-blind design, evaluation interval of primary endpoint > or = 6 months, multicenter (at least three centers), independent data and safety monitoring, power of > or = 80% for primary endpoint achieved, and follow-up > or = 80% for a surrogate primary endpoint or follow-up of > or = 95% for a clinical primary endpoint. Thus, the maximum achievable points is 10. This scoring system can also be applied for high-quality registry controlled trials using a predefined control group and power calculation. For simple registry studies and subgroup analyses, a modified scoring system has been developed (maximum achievable points is 5). The advantage of the suggested new scoring system is its transparency, reproducibility, and ease of use by quickly answering the key quality questions for clinical trials. The new scoring system suggested here should help make decisions regarding which treatment to use and stimulate discussions.
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Reperfusion therapy in ST-segment elevation myocardial infarction (STEMI) is the most important component of treatment, as it strongly influences short- and long-term patient outcome. The main objective of healthcare providers should be to achieve at least 75% of reperfusion therapy applied to patients suffering from STEMI in a timely manner, and preferably within the first 3 h after onset of symptoms. Establishing networks of reperfusion at regional and national level, implying close collaboration between all the actors involved in reperfusion therapy, namely hospitals, departments of cardiology, PCI centres, emergency medical systems (EMS), (para)medically staffed ambulances, private cardiologists, primary care physicians, etc., is a key issue. All forms of reperfusion, depending on local facilities, need to be available to patients. Protocols must be written and agreed for the strategy of reperfusion to be applied within a network. Early diagnosis of STEMI is essential and is best achieved by rapid ECG recording and interpretation at first medical contact, wherever this contact takes place (hospital or ambulance). Tele-transmission of ECG for immediate interpretation by experienced cardiologists is an alternative. Primary PCI is the preferred reperfusion option if it can be performed by experienced staff within 90 min after first medical contact. Thrombolytic treatment, administered if possible in the pre-hospital setting, is a valid option if PCI cannot be performed in a timely manner, particularly within the first 3 h following onset of symptoms. Thrombolysis is not the end of the reperfusion therapy. Rescue PCI must be performed in the case of thrombolysis failure. Next-day PCI after successful thrombolysis has been proven efficacious. Quality control is important for monitoring the efficacy of networks of reperfusion. All elements that influence time to reperfusion must be taken into account, particularly transfer delays, in-hospital delays, and door-to-balloon or door-to-needle times. The rate of reperfusion achieved must also be taken into consideration. Professional organizations such as the European Society of Cardiology (ESC) have the responsibility to impart this message to the cardiology community, and inform politicians and health authorities about the best possible strategy to achieve reperfusion therapy.
Early results with polymer-based paclitaxel-eluting stents have shown significant improvements in the clinical and angiographic parameters of restenosis, as well as excellent safety outcomes. However, the duration of these beneficial effects is unknown. Therefore, the clinical outcomes of the TAXUS I study population were evaluated at 2- and 3-year follow-up. In TAXUS I, 61 patients with single, focal coronary lesions were randomly assigned to receive either a paclitaxel-eluting TAXUS stent (n = 31) or a bare metal control stent (n = 30). Low rates of composite major adverse cardiac events (MACEs) reported at 1-year follow-up (3.2% TAXUS vs 10.0% control) were maintained at 2 and 3 years, with no additional MACEs in either treatment group 1 year after implantation. The single target vessel revascularization in the TAXUS group was remote from the target lesion in contrast to 3 target lesion revascularizations in the control group.
In patients with stable CAD, PCI can be considered a valuable initial mode of revascularization in all patients with objective large ischaemia in the presence of almost every lesion subset, with only one exception: chronic total occlusions that cannot be crossed. In early studies, there was a small survival advantage with CABG surgery compared with PCI without stenting. The addition of stents and newer adjunctive medications improved the outcome for PCI. The decision to recommend PCI or CABG surgery will be guided by technical improvements in cardiology or surgery, local expertise, and patients' preference. However, until proved otherwise, PCI should be used only with reservation in diabetics with multi-vessel disease and in patients with unprotected left main stenosis. The use of drug-eluting stents might change this situation. Patients presenting with NSTE-ACS (UA or NSTEMI) have to be stratified first for their risk of acute thrombotic complications. A clear benefit from early angiography (<48 h) and, when needed, PCI or CABG surgery has been reported only in the high-risk groups. Deferral of intervention does not improve outcome. Routine stenting is recommended on the basis of the predictability of the result and its immediate safety. In patients with STEMI, primary PCI should be the treatment of choice in patients presenting in a hospital with PCI facility and an experienced team. Patients with contra-indications to thrombolysis should be immediately transferred for primary PCI, because this might be their only chance for quickly opening the coronary artery. In cardiogenic shock, emergency PCI for complete revascularization may be life-saving and should be considered at an early stage. Compared with thrombolysis, randomized trials that transferred the patients for primary PCI to a 'heart attack centre' observed a better clinical outcome, despite transport times leading to a significantly longer delay between randomization and start of the treatment. The superiority of primary PCI over thrombolysis seems to be especially clinically relevant for the time interval between 3 and 12 h after onset of chest pain or other symptoms on the basis of its superior preservation of myocardium. Furthermore, with increasing time to presentation, major-adverse-cardiac-event rates increase after thrombolysis, but appear to remain relatively stable after primary PCI. Within the first 3 h after onset of chest pain or other symptoms, both reperfusion strategies seem equally effective in reducing infarct size and mortality. Therefore, thrombolysis is still a viable alternative to primary PCI, if it can be delivered within 3 h after onset of chest pain or other symptoms. Primary PCI compared with thrombolysis significantly reduced stroke. Overall, we prefer primary PCI over thrombolysis in the first 3 h of chest pain to prevent stroke, and in patients presenting 3-12 h after the onset of chest pain, to salvage myocardium and also to prevent stroke. At the moment, there is no evidence to recommend facilitated PCI. Rescue PCI is recommended, if thrombolysis failed within 45-60 min after starting the administration. After successful thrombolysis, the use of routine coronary angiography within 24 h and PCI, if applicable, is recommended even in asymptomatic patients without demonstrable ischaemia to improve patients' outcome. If a PCI centre is not available within 24 h, patients who have received successful thrombolysis with evidence of spontaneous or inducible ischaemia before discharge should be referred to coronary angiography and revascularized accordingly--independent of 'maximal' medical therapy.
BACKGROUND AND PURPOSE: It is generally known and accepted that percutaneous coronary intervention (PCI) has undergone a patient-relevant innovation with the introduction of drug-eluting stents (DES): prospective, randomized, controlled studies with a primary clinical endpoint have shown that DES, especially those releasing sirolimus from a polymer (SES) or those releasing paclitaxel from a polymer (PES), significantly and relevantly reduce the restenosis rate and hence the number of needed reinterventions in the target vessel (target vessel revascularization [TVR]) as compared to bare metal stents (BMS). For this improvement of quality of life, cost-effectiveness analyses comparing DES and BMS in the US and German health care systems have been reported. For the comparison of DES and coronary artery bypass graft surgery (CABG), no economic data regarding the German health care system have been published. The goal of the present study is to provide such an economic analysis investigating the question whether DES can reduce costs as compared to CABG within the German health care system. METHODS: Based on the clinical data for PCI with a PES for long and complex lesions (TAXUS VI) and for CABG (ARTS I), the comparison was calculated for the time interval of 1 year. The analysis of the PCI group was derived from a TVR of 11% including a CABG rate of 1%; the CABG group analysis was based on a TVR of 3.8% including a PCI rate of 3.1% and a re-CABG rate of 0.7%. At a stent factor of 2.75, the costs per stent were calculated to be 250 Euro for the BMS and 1,500 Euro for the PES. The total costs for 12 months included the follow-up costs for reinterventions. The results were tested for stability according to a sensitivity analysis. RESULTS: Patients' demographics were well comparable between the PCI and the CABG groups. The primary costs, including the reinterventions, were 7,841 Euro for PCI and 12,415 Euro for CABG. The sensitivity analysis revealed that only at more than eight stents per patient and a need for reintervention of ca. 10% did the cost of PCI with PES reach the level of the cost for CABG. CONCLUSION: Within the German health care system, in patients with a social insurance, PCI of long and complex lesions with PES significantly reduces costs as compared to CABG to the amount of 4,574 Euro per patient. The cost-effectiveness analyses of currently ongoing prospective, randomized trials (SYNTAX und FREEDOM) will provide more insight into the economic comparison of PCI with DES and CABG.
BACKGROUND: It is an ongoing concern that intracoronary brachytherapy may possibly just delay the problem of in-stent restenosis ("late catch up"). For gamma-radiation, 3 placebo-controlled studies have shown the maintenance of the initially positive effect after 2 years, but similar data do not exist for beta-radiation. STents And Restenosis Trial (START) was the first placebo-controlled randomized trial for in-stent restenosis with beta-radiation; herein, we report the 2-year clinical follow-up. METHODS AND RESULTS: Two hundred and forty-four patients were randomized to active treatment, 232 patients to placebo (nonactive source train) treatment. The primary end point of efficacy was target vessel revascularization (TVR); primary safety end point was any major adverse cardiac event (MACE) at 8 months and 2 years. Two-year clinical outcome in patients receiving brachytherapy was based on 195 of 244 original patients (79.9%) and in the placebo arm on 183 of 232 original patients (78.9%). TVR was significantly reduced by 25%; from 36.6% (placebo) to 27.5% (brachytherapy) remained significant after 2 years (RR .7 [.57-.98], 95% CI -9.2 [-17.5-0.8]). The Kaplan-Meier analysis for TVR and MACE showed improvement beginning approximately 90 days after radiation and remained almost constant for the 2 following years. Freedom from TVR was significantly increased from 62.4% +/- 3.8% to 71.6% +/- 3.3% (P = .027) and freedom from MACE from 58.9% +/- 3.7% to 68.0% +/- 3.4% (P = .035). CONCLUSIONS: The START trial shows for the first time that the initial beneficial effects of intracoronary brachytherapy with beta-radiation using 90 Sr/ 90 Y are maintained at 2-year clinical follow-up period.
Today, drug-eluting stents (DES) are the standard stenting procedure in the USA and in Switzerland. The objective of this analysis is to answer the two questions: what clinically relevant data regarding DES have been published, and is there a clinically relevant difference between the Cypher and the Taxus stents? Twenty-two randomized, controlled studies with a total of 11,118 patients were identified: 18 randomized studies compared a DES to a bare metal stent of identical design in 8,301 patients, and 4 randomized studies compared the Cypher and the Taxus stents in 2,817 patients. Three studies regarding Paclitaxel-releasing stents without polymer (1,235 pats) and five studies regarding Paclitaxel released from a polymer (3,513 pats) were analyzed. Sirolimus released from a polymer was investigated in five studies (2,070 pats). Everolimus released from a polymer was investigated in three studies (166 pats), Biolimus A9 released from a polymer in one (120 pats), and Zotarolimus (ABT-578) released from a polymer in also one (1,197 pats) trial. Thirteen studies chose either a surrogate primary endpoint (angiographic or IVUS) or a clinical endpoint insufficient for a power calculation. A primary clinical endpoint with an adequate sample size for a power calculation was chosen in three trials for the Taxus stent (TAXUS-IV, TAXUS-V, TAXUS-VI; 2,916 patients), in one trial for the Cypher stent (SIRIUS; 1,058 patients), and in one trial for the Endeavor stent (ENDEAVOR-II; 1,197 patients). In all these trials, the primary clinical endpoint was reached. Of the four studies comparing Cypher stents to Taxus stents, one did not define the primary endpoint (TAXi), two assumed superiority of the Cypher stent (REALITY with a surrogate endpoint and SIRTAX, a single-center study), and one was designed as a non-inferiority trial (ISAR-Diabetes, single-center study with a surrogate endpoint). Based on the European Society of Cardiology established strict criteria with a clinical primary endpoint as a prerequisite to recommend a DES, only three DES have thus far had proven positive effects on clinical outcome: the Cypher-stents, Taxus-stents, and Endeavor-stents. A trial proving the superiority of one DES over another would require a multicenter study with a clinical primary endpoint at an adequate power. As long as such a trial does not exist, Cypher and Taxus are regarded as being equivalent.
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OBJECTIVES: The Study to COmpare REstenosis Rate between QueST and QuaDDS-QP2 (SCORE) trial was a multicenter, randomized, open-label trial comparing the safety and performance of 13- and 17-mm QuaDDS stents (n = 126) (Quanam Medical Corp., Santa Clara, California/Boston Scientific Corp., Natick, Massachusetts) versus uncoated control stents (n = 140) in focal, de novo coronary lesions. BACKGROUND: The pioneering drug-delivery QuaDDS stent used four to six acrylate polymer sleeves, each loaded with 800 microg of the paclitaxel derivative 7-hexanoyltaxol. METHODS: Clinical end points were assessed at 1, 6, and 12 months post procedure. Quantitative coronary angiography and intravascular ultrasound were performed post procedure and at six-month follow-up. RESULTS: In the QuaDDS group, early stent thrombosis and myocardial infarction (MI) rates were significantly higher, leading to premature cessation of enrollment. For the QuaDDS group, the stent thrombosis rate increased from 3.2% to 10.3% between 1 and 12 months, associated with increased non-Q-wave MI and death rates. The angiographic restenosis rate at six months was reduced from 32.7% (control) to 7.4% (p < 0.0001). However, the primary end point was not met with six-month target vessel revascularization (TVR) rate as well as the composite major adverse cardiac event rates (cardiac death, MI, and TVR) comparable between groups. CONCLUSIONS: Despite angiographic indications of potential anti-restenotic benefit, increased rates of stent thrombosis, MI, and cardiac death associated with the QuaDDS stent show an unacceptable safety profile.
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