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Peter B Berger

Publications and source records attributed to Peter B Berger.

90 records · Page 5Linked to original sources
PubMed2002

The impact of renal insufficiency on clinical outcomes in patients undergoing percutaneous coronary interventions.

OBJECTIVES: We sought to determine the effect of varying degrees of renal insufficiency on death and cardiac events during and after a percutaneous coronary intervention (PCI). BACKGROUND: Patients with end-stage renal disease have a high mortality from coronary artery disease. Little is known about the impact of mild and moderate renal insufficiency on clinical outcomes after PCI. METHODS: Cardiac mortality and all-cause mortality were determined for 5,327 patients undergoing PCI from January 1, 1994, to August 31, 1999, at the Mayo Clinic, based on the estimated creatinine clearance or whether the patient was on dialysis. RESULTS: In-hospital mortality was significantly associated with renal insufficiency (p = 0.001). Even after successful PCI, one-year mortality was 1.5% when the creatinine clearance was > or =70 ml/min (n = 2,558), 3.6% when it was 50 to 69 ml/min (n = 1,458), 7.8% when it was 30 to 49 ml/min (n = 828) and 18.3% when it was < 30 ml/min (n = 141). The 18.3% mortality rate for the group with < 30 ml/min creatinine clearance was similar to the 19.9% mortality rate in patients on dialysis (n = 46). The mortality risk was largely independent of all other factors. CONCLUSIONS: Renal insufficiency is a strong predictor of death and subsequent cardiac events in a dose-dependent fashion during and after PCI. Patients with renal insufficiency have more baseline cardiovascular risk factors, but renal insufficiency is associated with an increased risk of death and other adverse cardiovascular events, independent of all other measured variables.

Aged↗
PubMed2002

Meta-analysis of randomized and registry comparisons of ticlopidine with clopidogrel after stenting.

OBJECTIVES: We sought to determine whether clopidogrel is at least as efficacious as ticlopidine. BACKGROUND: Several trials have supported the enhanced safety and tolerability of clopidogrel compared with ticlopidine after coronary stent deployment. However, none of these individual trials were powered to detect possible differences in the efficacy for reducing ischemic end points. METHODS: Published data from trials and registries that compared clopidogrel with ticlopidine in patients receiving coronary stents were pooled, and a formal meta-analysis was performed. The rate of 30-day major adverse cardiac events (MACE), as defined in each trial, was used as the primary end point. RESULTS: There were a total of 13,955 patients. The pooled rate of major adverse cardiac events was 2.10% in the clopidogrel group and 4.04% in the ticlopidine group. After adjustment for heterogeneity in the trials, the odds ratio (OR) of having an ischemic event with clopidogrel, as compared with ticlopidine, was 0.72 (95% confidence interval [CI] 0.59 to 0.89, p = 0.002). Mortality was also lower in the clopidogrel group compared with the ticlopidine group-0.48% versus 1.09% (OR 0.55, 95% CI 0.37 to 0.82; p = 0.003). CONCLUSIONS: Based on all available evidence from randomized clinical trials or registries, clopidogrel, in addition to better tolerability and fewer side effects, is at least as efficacious as ticlopidine in reducing MACE. This finding may be due to the more rapid onset of an antiplatelet effect seen with the loading dose of clopidogrel, which was used in most of these studies, or to better patient compliance with clopidogrel therapy. Therefore, clopidogrel plus aspirin should replace ticlopidine plus aspirin as the standard antiplatelet regimen after stent deployment.

Aspirin↗
PubMed2002

Lack of association between plasma homocysteine and angiographic coronary artery disease in the era of fortification of cereal grain flour with folic acid.

Homocysteine is associated with coronary disease (CAD). However, the strength of the association after accounting for traditional and emerging risk factors is unclear, particularly since flour fortification with folate was mandated in the USA. We analyzed the association between traditional and emerging risk factors and CAD in 504 patients undergoing clinically-indicated angiography between July 1998 and January 1999. Significant CAD (> or =50% stenosis in > or =1 artery) was present in 271 patients (54%). Mean homocysteine (micromol/l) was 9.36+/-3.07; hyperhomocysteinemia (>13 micromol/l) was present in 7.9% of patients. Mean homocysteine was 9.29+/-3.02 in patients with no disease (no stenoses or stenoses <10%), 9.09+/-2.47 in patients with mild disease (stenoses 10-50%), 9.12+/-2.39 in patients with one vessel disease (VD) (>50% stenosis in one coronary artery), 9.28+/-3.19 in patients with two VD, and 10.1+/-3.89 in patients with three VD (P=0.0793). Multivariate analysis that included age, gender, smoking, LDL, HDL, Lp(a), apo A1, and apo B revealed no independent association between quartile of homocysteine and odds ratio (OR) for CAD. In summary, we found no association between homocysteine and CAD on angiography. The homocysteine-lowering effect of folate-fortified flour, or the inclusion of many traditional and emerging risk factors in multivariate analysis, are potential explanations.

Adult↗
PubMed2002

Safety and efficacy of only 2 weeks of ticlopidine therapy in patients at increased risk of coronary stent thrombosis: results from the Antiplatelet Therapy alone versus Lovenox plus Antiplatelet therapy in patients at increased risk of Stent Thrombosis (ATLAST) trial.

BACKGROUND: Controversy exists regarding the frequency of late stent thrombosis among patients treated with intracoronary stents and the most appropriate duration of treatment with a thienopyridine that is required to prevent this complication. METHODS: We analyzed the frequency of stent thrombosis and other ischemic events in the Antiplatelet Therapy alone versus Lovenox plus Antiplatelet therapy in patients at increased risk of Stent Thrombosis (ATLAST) trial. In the ATLAST trial, 1102 patients at increased risk of stent thrombosis (ST-elevation myocardial infarction within 48 hours, diffuse distal disease, a large amount of thrombus, acute closure, residual dissection, etc) were randomly assigned to receive either enoxaparin (40 or 60 mg given every 12 hours for 14 days) or placebo; all patients received aspirin (325 mg daily) and ticlopidine (250 mg twice daily) for only 14 days. RESULTS: The primary end point, the 30-day combined incidence of death, nonfatal myocardial infarction, and urgent revascularization, was reached in 2.3% of patients (1.8% of patients taking enoxaparin vs 2.7% of patients taking placebo; P =.295). However, during the 15th through 30th days, the frequency of ischemic events was only 0.73%, and only 0.27% (3/1102) of patients had possible stent thrombosis (95% CI 0.06, 0.77). CONCLUSION: The frequency of stent thrombosis and other adverse ischemic events in the 15th through 30th days after stent placement in even high-risk stent patients treated with ticlopidine for only 2 weeks is low whether or not enoxaparin is administered.

Coronary Thrombosis↗
PubMed2002

The thienopyridines.

Platelet adhesion, activation, and aggregation are key processes in the pathogenesis of coronary disease. Inhibition of these processes forms the cornerstone of therapy for coronary artery disease and particularly of acute coronary syndromes (ACS). Aspirin was the only available antiplatelet therapy for over 100 years, and it improves clinical outcome in a wide range of clinical situations. However, aspirin only inhibits platelet activation mediated by thromboxane A2, allowing platelet activation to occur through innumerable other pathways. As a result, adverse ischemic events are common when aspirin alone is used for the treatment of coronary disease, including ACS, during coronary interventions (particularly during stent implantation), and following coronary vascular brachytherapy (VBT). In these clinical situations, the presence of either thrombus, deep injury to the vessel wall, or delayed vascular reendothelialization leads to intense and often prolonged platelet activation, overwhelming the relatively weak effects of aspirin. The development of the thienopyridines, a class of antiplatelet drugs that reduce adenosine diphosphate-(ADP) mediated platelet activation, has significantly improved clinical outcomes in many coronary conditions. Widespread use of ticlopidine, the first available thienopyridine, was limited by frequent side-effects, including life-threatening neutropenia and thrombotic thrombocytopenic purpura. Following the introduction of clopidogrel, a thienopyridine with an excellent safety profile, dual antiplatelet therapy with aspirin and clopidogrel has become standard therapy following coronary stent implantation and coronary VBT. In patients presenting with ACS, the addition of clopidogrel to aspirin has now been proven to reduce ischemic events. The most important limitation of dual antiplatelet therapy is the increased bleeding risk as compared with aspirin alone, particularly in patients undergoing coronary artery bypass grafting during the index hospitalization. However, for many patients with ACS, combination therapy is appropriate.

Clopidogrel↗
PubMed2002

Safety and efficacy of cutting balloon angioplasty: the Mayo Clinic experience.

UNLABELLED: A number of evolving clinical indications for cutting balloon angioplasty (CBA) have been described in the clinical literature, including angioplasty-resistant stenoses, in-stent restenosis, ostial lesions and small vessel disease. METHODS: We analyzed the Mayo Clinic PTCA registry and report procedural and in-hospital clinical outcomes in 100 patients (103 procedures, 114 lesions) undergoing CBA. RESULTS: CBA was successfully completed in 109 lesions (96%). The majority of lesions (73%) required additional treatment with either balloon angioplasty (39%) or stent implantation (34%). Severe intimal dissection resulting in at least 50% luminal obstruction occurred in 13 lesions (11%). A single incident of branch occlusion was documented, resulting in ST elevation myocardial infarction. There were no incidents of vessel perforation, urgent percutaneous or surgical target vessel revascularization, or in-hospital death. CONCLUSION: CBA is feasible and safe, with a low incidence of procedural complications and in-hospital adverse cardiac events when used primarily for in-stent restenosis.

Academic Medical Centers↗
PubMed2001

Distal protection devices during percutaneous coronary and carotid interventions.

Distal embolization of particulate matter complicates percutaneous coronary and peripheral interventions more often than had been recognized until recently. A number of distal protection devices are under development. The PercuSurge GuardWiretrade mark is a balloon occlusion thrombectomy device approved by the United States Food and Drug Administration for saphenous vein graft intervention. A number of filter devices utilize an expandable filter mounted on the angioplasty guidewire to facilitate entrapment of particles and safe removal. The Parodi Anti-Emboli Systemtrade mark is an example of a catheter occlusion device that establishes protection by reversing blood flow in the target vessel.

Journal Article↗
PubMed2000

Results of the Ticlid or Plavix Post-Stents (TOPPS) trial: do they justify the switch from ticlopidine to clopidogrel after coronary stent placement?

In the Ticlid or Plavix Post-Stents (TOPPS) trial, 1016 patients undergoing successful coronary stent placement were randomized to receive aspirin and either ticlopidine or clopidogrel. In this trial, the dosages and regimens of ticlopidine and clopidogrel resembled more closely those used in most catheterization laboratories than did the two previous randomized trials comparing ticlopidine and clopidogrel. The results of the TOPPS trial support the current practice of substituting ticlopidine for clopidogrel in stent patients.

Journal Article↗