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Roswitha Wolfram

Publications and source records attributed to Roswitha Wolfram.

At least 19 recordsLinked to original sources
PubMed2006

Role of prophylactic intra-aortic balloon pump in high-risk patients undergoing percutaneous coronary intervention.

Intra-aortic balloon pump (IABP) has been shown to support patients who are at high risk for percutaneous coronary interventions (PCIs) or becoming hemodynamically unstable during PCI, but the longer term outcomes of these strategies are unknown. This study investigated the outcomes of high-risk patients who received a prophylactic IABP (P-IABP) versus patients who required rescue IABP (R-IABP) because of intraprocedural complications. Clinical outcomes of 68 consecutive patients (69 procedures) who underwent high-risk PCI with P-IABP support were compared with those of 46 patients who required R-IABP. Patients who presented with cardiogenic shock or acute ST-segment elevation myocardial infarction, and those who were on mechanical ventilators were excluded. Clinical baseline characteristics were similar between groups except for more diabetics and patients with hypercholesterolemia in the P-IABP group. The procedural success was higher in the P-IABP group, with lower in-hospital mortality and major complications, than in the R-IABP group. At 6 months, the mortality and major adverse cardiac event rates were lower in the P-IABP group (8% vs 29%, p < 0.01, and 12% vs 32%, p = 0.02, respectively). Multivariate analysis showed that prophylactic insertion of an IABP is the only independent predictor of survival at 6 months. The incidence of vascular complications was low and comparable except for more major bleeding (15% vs 3%, p = 0.03) in the R-IABP group. In conclusion, patients who undergo high-risk PCI and then receive P-IABP support have favorable outcomes compared with those who require R-IABP for intraprocedural complications. Therefore, in high-risk patients undergoing PCI, liberal use of a P-IABP should be considered.

Aged↗
PubMed2006

Sirolimus-eluting stents versus Paclitaxel-eluting stents in the treatment of coronary artery disease in patients with diabetes mellitus.

This study was performed to compare the safety and efficacy of sirolimus-eluting stents (SESs) and paclitaxel-eluting stents (PESs) on the outcomes of diabetic patients. Recent data with drug-eluting stents have shown improved clinical outcomes in diabetic patients. This study compared outcomes between the 2 available drug-eluting stents, SESs and PESs. From the prospective drug-eluting stent registries at the investigators' institution, 1,320 consecutive diabetic patients treated with SESs (n=873, 1,293 lesions) and PESs (n=447, 733 lesions) were identified and their in-hospital and 1- and 6-month clinical outcomes compared. Baseline characteristics showed more men, more patients with previous coronary bypass surgery, and smaller ejection fractions in the PES group and more obese patients in the SES group. Procedural characteristics were similar except for more left anterior descending artery and proximal lesions and the greater use of glycoprotein IIb/IIIa inhibitors in the SES group and more type C lesions, direct stenting, and stents per patient in the PES group. In-hospital complications were similar. Clinical follow-up at 1 month was also similar between the 2 groups, including subacute stent thrombosis. At 6 months, the 2 groups had similar mortality (7% vs 7%), myocardial infarctions (18% vs 21%), target lesion revascularization, target vessel revascularization, major adverse cardiac events (11% vs 12%), and late thrombosis (0.3% vs 0%). Subanalysis of insulin-treated diabetic patients showed no significant differences in outcomes in the 2 groups. No significant differences were found between SESs and PESs on Cox regression analysis for hazard ratios. In conclusion, SESs and PESs are associated with similar efficacy and safety with regard to repeat revascularization rates, major adverse cardiac events, and stent thrombosis up to 6 months for the treatment of coronary artery disease in patients with diabetes mellitus regardless of insulin therapy.

Aged↗
PubMed2005

Enhanced oxidative stress in coronary heart disease and chronic heart failure as indicated by an increased 8-epi-PGF(2alpha).

The role of oxidation injury as an important factor in the pathophysiology of cardiomyopathy (CMP) has recently gained increasing interest. Semiquantitative analysis for isoprostane, 8-epi-prostaglandin F(2alpha) (8-epi-PGF(2alpha)), and oxidised low-density lipoprotein (ox-LDL) of coronary vascular tissue samples derived from CMP patients revealed an increased extent and intensity of uptake as compared to the respective controls. To evaluate oxidative stress in vivo, we examined plasma, serum, salivary, and urinary 8-epi-PGF(2alpha) in patients with dilated CMP (n=20) and ischemic CMP (n=20) with decreased left ventricular ejection fraction (LVEF). Patients with coronary heart disease (CHD) (n=20) and 20 healthy, age-matched, and sex-matched controls were investigated in parallel. 8-Epi-PGF(2alpha) levels were correlated with the functional severity of heart failure [New York Heart Association (NYHA) classification] and LVEF. 8-Epi-PGF(2alpha) levels were matched according to risk factors (smoking and hypercholesterolemia) and were significantly higher in patients with CMP as compared to healthy controls and patients with CHD in all investigated compartments. A positive correlation between NYHA stages and 8-epi-PGF(2alpha), as well as a negative correlation to LVEF, could be demonstrated in a subgroup analysis. These findings reflect the enhanced oxidation injury in patients with CMP and, to a lesser extent, in CHD as compared to healthy controls, thus highly indicating the relevance of oxidative stress for the pathogenesis and progression of cardiovascular disease.

Adult↗
PubMed2005

Novel site-specific systemic delivery of Rapamycin with perfluorobutane gas microbubble carrier reduced neointimal formation in a porcine coronary restenosis model.

Earlier studies demonstrated that perfluorobutane gas microbubble carrier (PGMC) adheres to injured arteries and enhances the drug uptake specifically into the cells of the denuded vessel segment. The purpose of this study was to investigate the effect of PGMC-based systemic delivery of Rapamycin on expression of p27 in vascular tissue and restenosis in porcine coronary arteries after stent implantation. Eight pigs underwent coronary stent implantation (three stents per animal). Five pigs were treated with i.v. injection of PGMC with 2 mg of Rapamycin and three animals served as control. Four hours postprocedure, three pigs were sacrificed and stented segments were analyzed by high-performance liquid chromatography (HPLC) and Western blot. In chronic experiments, five pigs (15 stent sites) were sacrificed at 28 days following intervention and vessels were perfusion-fixed. HPLC of the treated arteries demonstrated high drug concentration in the vessel tissue, and Western blot analysis showed elevated expression of p27 at 4 hr postprocedure. Histomorphometry revealed significantly reduced (by 40%) neointimal formation in the PGMC/Rapamycin group compared with controls (1.84 +/- 0.84 vs. 4.77 +/- 1.71 mm2, respectively; P < 0.001). In the porcine coronary model, site-specific systemic delivery of Rapamycin utilizing PGMC resulted in overexpression of p27 and a significant reduction of neointimal formation within the stented segments.

Animals↗
PubMed2005

Brachytherapy and bivalirudin evaluation study.

BACKGROUND: Bivalirudin is shown to be a competent substitute for heparin in percutaneous coronary intervention (PCI). The safety and efficacy of bivalirudin in patients undergoing PCI and vascular brachytherapy (VBT) are not known. This study aimed to assess the safety and efficacy of bivalirudin as a single antithrombotic agent in patients undergoing PCI and VBT. METHODS: A total of 152 patients enrolled in the Brachytherapy and Bivalirudin Evaluation Study underwent PCI and VBT with either gamma (n = 8) or beta radiation (n = 144). The main outcome measures were in-hospital events and 30-day clinical outcomes. All patients were treated with bivalirudin (0.75 mg/kg bolus and 1.75 mg/kg per hour infusion for beta radiation, 1 mg/kg bolus and 2.5 mg/kg per hour infusion for gamma radiation) as a single antithrombotic agent during the entire procedure. RESULTS: Baseline clinical and angiographic characteristics were similar between the 2 groups. More than 90% of the patients received beta radiation. In-hospital events showed a higher prevalence of acute procedural intracoronary thrombosis in patients treated with gamma- vs beta radiation (25% vs. 0.7%, P < .001). Thirty-day outcomes including death, Q-wave, and non-Q-wave myocardial infarctions, subacute stent thromboses, and repeat revascularizations were similar in both groups. CONCLUSION: Bivalirudin, as a single antithrombotic agent during PCI and VBT with beta emitters, may be used safely, but its use in the setting of PCI and gamma radiation may not be acceptable due to an increased incidence of acute procedural intracoronary thrombosis.

Angioplasty, Balloon, Coronary↗
PubMed2004

Angiographic and clinical outcomes of late total occlusion versus treatment failure without late total occlusion in patients after intracoronary radiation therapy for in-stent restenosis.

This study aimed to compare the outcomes of patients with late total occlusion (LTO) versus patients with recurrence in the absence of LTO after intracoronary radiation therapy for in-stent restenosis. LTO, especially in the context of acute myocardial infarction, after intracoronary radiation therapy for in-stent restenosis, is associated with negative clinical outcomes after 6 and 12 months compared with in-stent restenosis without LTO.

Brachytherapy↗
PubMed2004

Comparison of baseline characteristics and one-year outcomes between African-Americans and Caucasians undergoing percutaneous coronary intervention.

The objectives of this study were to determine whether there are race-based differences in baseline characteristics and in short- or long-term outcomes after percutaneous coronary intervention (PCI). African-Americans have a higher incidence of coronary artery disease but are less likely to undergo coronary revascularization than Caucasians. Little is known about the profiles and outcomes of African-Americans who undergo PCI. Consecutive series of 1,268 African-Americans and 10,561 Caucasians with symptomatic coronary artery disease who underwent PCI between January 1994 and June 2001 were analyzed. Patients hospitalized for acute myocardial infarction were excluded. African-Americans were older, were more likely to be women, and had more co-morbid baseline conditions compared with Caucasians. Preprocedure lesion characteristics were similar with regard to vessel size, length, and complexity. The rate of clinical success did not differ between the groups. African-Americans experienced more in-hospital combined events of death and Q-wave myocardial infarction (p = 0.03). After propensity score adjustment, African-American race was not an independent predictor for in-hospital events. At 1 year, African-Americans had a slightly lower rate of target lesion revascularization and a 50% higher rate of death (9.8% vs. 6.4%, p <0.001), with a relative risk of 1.52 (95% confidence interval 1.22 to 1.89). In multivariate analysis, African-American race remained a significant predictor of increased 1-year mortality (hazard ratio 1.35, 95% confidence interval 1.06 to 1.71, p = 0.01). African-Americans undergoing angioplasty have more co-morbid baseline conditions than Caucasians. Despite similar clinical success, 1-year outcomes are impaired in African-Americans.

Aged↗
PubMed2004

Effects of gamma radiation on the noninjured and unprotected left main.

The aim of this study was to evaluate the effect of gamma radiation on the noninjured, unprotected left main coronary artery. Noninjured vessel segments are often radiated during treatment of in-stent restenosis with PCI and gamma radiation. Angiographic analysis using QCA methods was performed on 55 left main arteries of patients (32 with radiation of the left main compared to 23 controls) who participated in the Washington Radiation for In-Stent Restenosis Trials (WRIST). Baseline demographics and follow-up were comparable between the two groups, concluding that gamma radiation with long radiation safety margins is feasible and safe. Gamma radiation of noninjured irradiated left main vessels when used to facilitate wide radiation margins for proximal irradiated injured LAD and LCx is safe and does not compromise the vessel integrity and its lumen.

Aged↗
PubMed2004

Effects of contrast media on porcine bone marrow-derived mononuclear cells and calf myoblast viability and secretion of VEGF and MCP-1.

We investigated the effect of contrast media on bone marrow-derived cell viability, growth factor secretion, and myoblast viability. Bone marrow was exposed to contrast media, mononuclear cells were isolated, viability was assessed by Trypan blue exclusion or cultured for 4 weeks, and conditioned medium was assayed for vascular endothelial growth factor (VEGF) and monocyte chemoattractant protein-1 (MCP-1). Skeletal myoblasts viability was assessed after exposing them to contrast media. In separate experiments, bone marrow or bone marrow-derived mononuclear cells were exposed to contrast media, cultured for 40 hr, then assessed for viability. None of the contrast media tested had any effect on bone marrow-derived cell viability. Hypaque or Hexabrix increased myoblasts viability by 8-10%. VEGF and MCP-1 concentrations in the conditioned medium increased in a time-related manner. These findings support the concept that for cell therapy, bone marrow cells or myoblasts may be mixed with contrast media and injected into ischemic myocardium without compromise in viability or function.

Animals↗
PubMed2003

Comparison of effectiveness and safety of three different antithrombotic regimens (bivalirudin, eptifibatide, and heparin) in preventing myocardial ischemia during percutaneous coronary intervention.

The aim of this retrospective, observational analysis was to compare the efficacy and safety of 3 antithrombotic regimens: bivalirudin, eptifibatide plus heparin, and heparin alone, with emphasis on preventing interventional procedural creatinine kinase-MB fraction (CK-MB) release, and consequently, myocardial necrosis.

Aged↗
PubMed2003

Comparison of creatine kinase elevation and outcome of comparison of percutaneous coronary intervention for saphenous vein graft in-stent restenosis versus de novo stenosis.

Percutaneous coronary intervention of saphenous vein grafts is associated with distal embolization. We aimed to compare potential differences in patients undergoing percutaneous coronary intervention for in-stent restenosis with de novo saphenous vein graft lesions. Myocardial necrosis was associated with higher mortality regardless of lesion type.

Age Factors↗
PubMed2003

Repeat intracoronary radiation for recurrent in-stent restenosis in patients who failed intracoronary radiation.

BACKGROUND: Intracoronary radiation therapy (IRT) is the only proven treatment for in-stent restenosis (ISR). It is, however, associated with a significant failure rate. The present study evaluated the outcomes of patients who underwent repeat intracoronary radiation for recurrent ISR. METHODS AND RESULTS: Fifty-one consecutive patients who failed a previous radiation treatment, presented with angina and angiographic evidence of ISR, and were treated with percutaneous coronary intervention (PCI) and repeat radiation to the same segment were studied. Twenty-five patients were treated with gamma radiation in a dose of 15 Gy, and 26 were treated with beta radiation doses of 18.3 to 23 Gy. The mean cumulative dose for this cohort was 39.5+/-11.9 Gy (range, 29 to 75.6 Gy). The outcomes of those patients were compared with outcomes of 299 patients who also failed initial radiation but were treated with repeat conventional PCI to a previously irradiated segment without repeat radiation. At 9 months after treatment, the repeat-IRT group had lower rates of target lesion revascularization (23.5% versus 54.6%; P<0.001) and major adverse cardiac events, including target vessel revascularization (29.4% versus 61.3%; P<0.001). At 9 months, patients with repeat IRT were free of angiographic and clinical events related to the radiation therapy. CONCLUSIONS: Repeat gamma or beta radiation to treat failed IRT for ISR after conventional PCI is safe and effective at 9 months and should be considered as a therapeutic option for this difficult patient subset.

Angina Pectoris↗
PubMed2003

Use of restenting should be minimized with intracoronary radiation therapy for in-stent restenosis.

Restenting at the time of intracoronary radiation therapy (IRT) for in-stent restenosis (ISR) potentially increases the risk of late total occlusion (LTO) of the treated vessel. Prolonged antiplatelet therapy with clopidogrel (6 months) has been shown to be effective in reducing LTO risk. The purpose of this study was to assess the impact of restenting on clinical outcomes following IRT for ISR with 6 months of clopidogrel. We retrospectively evaluated 1,275 patients with 6-months clinical follow-up who were enrolled in radiation trials for ISR using gamma- and beta-emitters conducted at Washington Hospital Center. Patients were analyzed according to whether additional stents were deployed at the time of IRT. The predominant indication for restenting was to optimize the final angiographic result in the event of tissue prolapse or to cover edge dissections. All patients received a minimum of 6 months of clopidogrel. Baseline clinical and angiographic characteristics were similar between the restented and nonrestented groups. Radiation was delivered successfully in all cases. At 6 months, patients treated with additional stents and IRT had a significantly higher rate of target vessel revascularization than patients without additional stents (24.6% vs. 18.7%; P = 0.011). Restenting caused more frequent late thrombosis, late total occlusion, and Q-wave myocardial infarction than no restenting (4.0% vs. 2.2%, P = 0.09; 6.1% vs. 4.3%, P = 0.14; and 1.9% vs. 0.4%, P = 0.009, respectively). Restenting for the treatment of ISR is associated with increased adverse events and should be avoided after intracoronary radiation therapy for in-stent restenosis, as restenting results in a higher recurrence rate and the potential for increased late total occlusion.

Brachytherapy↗
PubMed2003

Endovascular Brachytherapy in Peripheral Arteries: Solution for Restenosis or False Hope?

Endovascular brachytherapy with gamma-radioactive source ((192)iridium ) significantly reduces the restenosis after femoropopliteal angioplasty for both de novo and recurrent lesions. Increased arterial patency after additional stenting and brachytherapy was also achieved with the same approach. This was found as a result of single-center studies performed in Frankfurt, Germany, Vienna, Austria, and Bern, Switzerland. However, until recently, only one multicenter investigation was published that also underlined this positive effect of brachytherapy. A definitive role of radiotherapy in restenosis prevention should be established after the results of three multicenter, phase III trials (ie, Paris, Vienna-3, and Swiss) are presented in early 2003. These investigations recruited approximately 630 patients with recurrent and de novo lesions without stent placement. Another important phase III study, the results of which are also expected at the beginning of 2003, is the Vienna-5 trial. This study had the same inclusion criteria as the Paris and Vienna-3 trials, but angioplasty was combined in all patients with stenting. The patients were then randomized for brachytherapy or sham irradiation. Endovascular brachytherapy has shown to be a safe treatment modality. The only clinically relevant impediment was the late sudden thrombosis or occlusion that occurred after stenting and radiation. These events can present up to 1 year after brachytherapy, and in some cases even later. Prolonged antiplatelet medication with clopidogrel (at least 12 months) has solved this problem completely. No other major adverse effects were seen. If gamma radiation is used, the patients must be transported after intervention to the brachytherapy suite, owing to radiation safety regulations. Although no negative consequences during transportation were observed in all performed studies, this represents an additional risk. To shorten the whole procedure, studies using beta sources ((32)phosphorus, (90)strontium) are ongoing, whereas those with beta-radioactive sources of brachytherapy can be performed in the catheterization laboratory. Emerging approaches using drug-eluting stents with antiproliferative substances such as rapamycin and paclitaxel are being investigated as well; however, the safety and efficacy for restenosis prophylaxis must be proven in large clinical trials.

Journal Article↗
PubMed2003

Understanding and preventing the edge effect.

Edge stenosis, combining neointimal proliferation and negative remodeling, remains a serious limitation of vascular brachytherapy. This review comprehensively presents terminology, definitions, mechanisms, and treatment strategies to better understand the complexities of edge narrowing. The major contributors to this phenomenon are known; understanding the practical solutions will enable us to further minimize the problem of the edge effect.

Brachytherapy↗
PubMed2003

Late thrombosis: a problem solved?

Late thrombosis (angiographic total occlusion associated with an acute coronary syndrome) is a potentially life-threatening complication after intracoronary radiation therapy. This review is intended to explore the preclinical and clinical evidence for late thrombosis, to discuss the etiology, and to provide guidelines for future management. Although we have gained a greater understanding of this complex entity, further research is required in a quest to curtail late thrombosis rates.

Animals↗