Preimplantation renal biopsy: structure does predict function.
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Glomerulosclerosis, Focal Segmental↗
Biomedical subjects
David J Cohen
Publications and source records attributed to David J Cohen.
Combination platelet glycoprotein IIb/IIIa receptor and lepirudin administration during percutaneous coronary intervention in patients with heparin-induced thrombocytopenia.
We evaluated a combination therapy using glycoprotein IIb/IIIa receptor antagonism and direct thrombin inhibition in nine patients with heparin-induced thrombocytopenia (HIT) undergoing 10 percutaneous coronary interventions (PCIs). In selected patients with HIT, the combination of a direct thrombin inhibitor, lepirudin, and abciximab, tirofiban, or eptifibatide appears to be a safe and effective anticoagulation strategy for PCI.
Abciximab↗
Comparison of analytic approaches for the economic evaluation of new technologies alongside multicenter clinical trials.
BACKGROUND: In reporting economic evaluations of clinical trials, results are often stated without a description of the methodology used to derive the cost estimates. We compared methods for measuring costs from multicenter clinical trials to determine the extent to which the methodology affects results. METHODS: Patient-level data (n = 1849) from 3 multicenter clinical trials of percutaneous coronary revascularization were used to compare 4 methods of estimating costs: 1) hospital charges; 2) hospital charges converted to costs by use of hospital-level cost-to-charge ratios; 3) hospital charges converted to costs by use of department-level cost-to-charge ratios; 4) itemized catheterization laboratory costs with nonprocedural hospital costs generated from department-level cost-to-charge ratios. RESULTS: The method used to approximate costs did not affect the main results of the economic comparisons for any of the trials. The magnitude of the cost estimates and the cost differences between treatment groups varied considerably by method, however. Charges were approximately twice as high as hospital cost estimates. At the patient level, costs generated by use of method 1 were within 10% of those generated by use of method 4 for only 5% of patients, compared with 34% and 22% of patients with methods 2 and 3, respectively. Only method 3 produced estimates of between-group cost differences that were consistently within $500 of the reference standard. CONCLUSION: Cost estimates derived from clinical trials in the cardiovascular arena vary substantially according to accounting methodology. Thus, in reporting the results of economic analyses, a detailed description of cost derivation is necessary, particularly when the absolute magnitude of the cost estimates is important to clinical decision-making or policy-level recommendations. For the purposes of group-level comparisons, conversion of hospital charges to costs on the basis of department-level cost-to-charge ratios appears to represent a reasonable compromise between accuracy and ease of implementation.
Angioplasty, Balloon, Coronary↗
Clinical and economic outcomes of multivessel coronary stenting compared with bypass surgery: a single-center US experience.
BACKGROUND: Randomized trials comparing multivessel stenting with coronary artery bypass surgery (CABG) have demonstrated similar rates of death and myocardial infarction but higher rates of repeat revascularization after stenting. The impact of these alternative strategies on overall medical care costs is uncertain, particularly within the US health care system. METHODS: We performed a retrospective, matched cohort study to compare the clinical and economic outcomes of multivessel stenting and bypass surgery. The stent group consisted of 100 consecutive patients who underwent stenting of >or=2 major native coronary arteries at our institution. The CABG group consisted of 200 patients who underwent nonemergent isolated bypass surgery during the same time frame, matched (2:1) for age, sex, ejection fraction, diabetes mellitus, and extent of coronary disease. Detailed clinical follow-up and resource utilization data were collected for a minimum of 2 years. Total costs were calculated by use of year 2000 unit prices. RESULTS: Over a median follow up period of 2.8 years, there were no significant differences in all-cause mortality rates (3.0% vs 3.0%), Q-wave myocardial infarction (5.1% vs 4.0%), or the composite of death or myocardial infarction (7.1% vs 7.0%) between the stent and CABG groups (P = not significant for all comparisons). However, at 2-year follow up, patients with stents were more likely to require >or=1 repeat revascularization procedure (32.0% vs 4.5%, P <.001). The initial cost of multivessel stenting was 43% less than the cost of CABG (11,810 dollars vs 20,574 dollars, P <.001) and remained 27% less (17,634 dollars vs 24,288 dollars, P =.005) at 2 years. CONCLUSIONS: Multivessel stenting and CABG result in comparable risks of death and myocardial infarction. Despite a higher rate of repeat revascularization, multivessel stenting was significantly less costly than CABG through the first 2 years of follow-up.
Angioplasty, Balloon, Coronary↗
Nephrogenic fibrosing dermopathy (scleromyxedema-like illness of renal disease).
Nephrogenic fibrosing dermopathy or scleromyxedema-like illness of renal disease is a recently reported disorder. It manifests as scleromyxedema-like skin lesions without associated paraproteinemia, occurring in the setting of renal disease. In the majority of cases skin lesions of nephrogenic fibrosing dermopathy develop after hemodialysis or renal transplantation; however, the origin is still unknown. We report 4 new cases of nephrogenic fibrosing dermopathy and review the literature. The clinical and histopathologic features, differential diagnosis, possible etiology, and treatment options are reviewed.
Adult↗
Upregulation of MHC class II, interferon-alpha and interferon-gamma receptor protein expression in HIV-associated nephropathy.
BACKGROUND: Renal cellular HIV infection has been linked to the pathogenesis of HIV-associated nephropathy (HIVAN), but mediators of its development are unknown. HIV infection is associated with disordered cytokine metabolism, and chemokine receptors are coreceptors for HIV immune cellular infection. Chemokines such as interleukin (IL)-8, monocyte chemoattractant protein-1 (MCP-1) and RANTES, and interferons (IFNs) have been implicated in the progression of nephropathy. Renal major histocompatibility complex (MHC) protein expression is involved in antigen presentation and modulating tissue cellular immune responses. Their relative importance in HIVAN pathogenesis is unknown. METHODS: We measured levels of chemokines, IFN-alpha, IFN-gamma receptor and non-polymorphic MHC Class II protein by high performance capillary electrophoresis, and incubation with antibodies for quantification by chemiluminesce in renal tissue of patients with HIVAN, compared with tissue without HIV infection, in the presence and absence of nephropathy. Renal biopsy tissue protein levels were correlated with the number and type of infiltrating tissue immune cells. RESULTS: Mean renal interstitial and glomerular MCP-1, RANTES and IL-8 tissue levels were higher in patients with HIV infection compared with tissue without HIV infection, regardless of the presence of renal disease. In contrast, mean renal interstitial and glomerular non-polymorphic MHC Class II, IFN-alpha and IFN-gamma receptor protein were higher in patients with HIVAN compared with all other groups. Tissue MHC Class II and IFN-gamma receptor protein levels did not correlate with immune cellular infiltration in patients with HIV infection and renal disease. CONCLUSIONS: The data suggest an upregulated renal immune microenvironment, capable of antigen presentation, exists in HIVAN. MHC Class II proteins and IFNs, and the capacity to present antigen may be crucial in HIVAN pathogenesis.
AIDS-Associated Nephropathy↗
Epidermodysplasia verruciformis.
Epidermodysplasia verruciformis is an uncommon cutaneous entity characterized by persistent human papillomavirus infection. A defect in cell-mediated immunity is the suggested causative factor. Numerous specific human papillomavirus types have been detected in this disease. Multiple nonmelanoma skin cancers are commonly seen in such patients; thus, early diagnosis is beneficial.
Epidermodysplasia Verruciformis↗
Practice and outcomes of percutaneous coronary intervention in the community before drug-eluting stents: a report from the HCA database.
BACKGROUND: Percutaneous coronary intervention (PCI) using balloon angioplasty and/or intracoronary stents has increasingly become the treatment choice for myocardial revascularization. While acute clinical outcomes of the community-based PCI procedures have been examined, much less is known about long-term revascularization rates, disease progression and other adverse outcomes. METHODS AND RESULTS: Information on patient demographics, coronary risk factors, lesion characteristics, procedures and outcomes were derived from an HCA, Inc. database on all patients undergoing a PCI procedure in one of four community cardiac catheterization laboratories. A total of 3,192 consecutive patients were enrolled from July 1, 1999 through September 30, 2000. Analysis was limited to those patients undergoing PCI of native vessels with stents or conventional balloon angioplasty; target lesions in bypass grafts or those treated with atherectomy were excluded. Approximately one-third of enrolled patients were surveyed concerning their utilization of cardiovascular services 1 year following their initial procedure. The 1-year target lesion revascularization (TLR) was 9.9% while target vessel revascularization was 13.5%. Overall, 27.6% of patients underwent repeat revascularization within 1 year; 24.7% underwent at least 1 additional PCI and 5.6% underwent coronary artery bypass graft surgery. A total of 4.5% of patients reported an interval acute myocardial infarction with a major adverse cardiac event rate of 30.3% at 1 year. CONCLUSION: While clinically significant restenosis remains a problem for 10 15% of patients undergoing PCI, progression of coronary artery disease elsewhere appears to be an equally powerful driver in the need for recurrent revascularization. This analysis of contemporary PCI practice prior to drug-eluting stent utilization suggests that while these novel devices will likely reduce the incidence of TLR, many patients with coronary artery disease will still require additional revascularization for disease progression.
Aged↗
The influence of diabetes mellitus on the practice and outcomes of percutaneous coronary intervention in the community: a report from the HCA database.
BACKGROUND: Diabetics remain a high-risk group for those undergoing percutaneous coronary intervention (PCI) using balloon angioplasty and/or intracoronary stents for myocardial revascularization. The objective of this study is to compare clinical characteristics, demographics, procedure indications, lesion characteristics, and acute and long-term outcomes between diabetic patients and non-diabetic patients in a community based PCI registry. METHODS AND RESULTS: Information on patient demographics, coronary risk factors, lesion characteristics, procedures, and outcomes were derived from an HCA, Inc. database on all patients undergoing a PCI procedure in one of four community cardiac catheterization laboratories (CCL). A total of 3,139 patients who underwent PCI procedures from July 1, 1999 through September 30, 2000 were enrolled in this study. Approximately one-third of these patients completed a follow-up survey one year after their initial encounter. Analysis was limited to those patients undergoing PCI of native vessels with stents or conventional balloon angioplasty; patients with target lesions in bypass grafts or those treated with atherectomy were excluded. Approximately 23.5% of the patients enrolled in the study were diabetic. This study found no significant difference in any acute outcome between diabetic and non-diabetic patients in the hospital episode associated with the index PCI procedure. However, data from the 1-year follow-up survey indicates diabetic patients tended to have more target lesion revascularization (TLR) (13.6% versus 8.9%; p = 0.07) and more target vessel revascularization (TVR) (17.6% versus 12.7%; p = 0.058) than non-diabetic patients. In addition, adjusted odds ratios indicate that diabetic patients were 1.6 times more likely to have a second PCI procedure in another vessel (p = 0.013), 2.4 times more likely to undergo bypass surgery (p = 0.003), 1.9 times more likely to undergo an additional revascularization procedure (p < 0.001) and 1.8 times more likely to experience any major adverse cardiac events (p < 0.001) than non-diabetic patients during the follow-up period. CONCLUSIONS: This study indicates that selected diabetic patients can be treated for myocardial revascularization using PCI procedures with acceptable acute outcomes. However, diabetic patients undergoing PCIs have significantly more disease progression and are more likely to experience the need for recurrent revascularization.
Aged↗
Clinical restenosis after coronary stenting: perspectives from multicenter clinical trials.
OBJECTIVES: We sought to evaluate clinical restenosis in a large population of patients who had undergone coronary stent placement. BACKGROUND: One-year success after coronary stenting is limited mainly by restenosis of and requirement for repeat revascularization of the treated lesion. We studied 6,186 patients (6,219 lesions) pooled from several recently completed coronary stent trials. Clinical restenosis was defined using three different definitions: target lesion revascularization (TLR) beyond 30 days, target vessel revascularization (TVR) beyond 30 days, and target vessel failure (TVF), defined as TVR, any death, or myocardial infarction (MI) of the target vessel territory after hospital discharge. RESULTS: By one year, 638 (12.2%) patients had TLR, 748 (14.3%) had TVR, and 848 (16.0%) had TVF, more than two-thirds higher than the rate of these end points at six months. The severity of angiographic restenosis (> or =50% follow-up diameter stenosis [DS]) in 419 of 1,437 (29%) patients undergoing routine angiographic follow-up correlated directly with the likelihood of TLR (73% vs. 26% for >70% DS compared with <60% DS). Smaller pretreatment minimum lumen diameter (MLD), smaller final MLD, longer stent length, diabetes mellitus, unstable angina, and hypertension were independent predictors of TLR. Prior MI and current smoking were negative predictors. CONCLUSIONS: At one year after stenting, most clinical restenosis reflected TLR, which was predicted by the same variables previously associated with an increased risk of angiographic restenosis. The lower absolute rate of clinical restenosis relative to angiographic restenosis was due to infrequent TLR in lesions with less severe (<60% DS) angiographic renarrowing.
Angioplasty, Balloon↗
Invasive vs conservative management of acute coronary syndromes: do the data support the guidelines?
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Acute Disease↗
Effectiveness of rheolytic coronary thrombectomy with the AngioJet catheter.
Thrombus-filled lesions are associated with a higher rate of acute complications and long-term restenosis following conventional coronary or saphenous vein graft (SVG) intervention. To evaluate the clinical effectiveness of rheolytic thrombectomy in a nonselected population in the glycoprotein IIb/IIIa blockade era, we reviewed clinical, angiographic, and procedural data on 119 patients who underwent 126 consecutive coronary AngioJet procedures (29% in SVGs, and 71% in native coronary arteries) from July 1998 to August 2000. Glycoprotein IIb/IIIa blockers were used in 88%. Most vessels (68% of SVGs, 74% of native coronary arteries) were occluded initially. Complete or substantial removal of filling defects was achieved in 76% of SVGs and 66% of native coronary cases. The AngioJet rheolytic thrombectomy device led to significant improvement in lumen diameter and Thrombolysis In Myocardial Infarction (TIMI) flow, with reduction in the thrombotic lesion length (p <0.05). Angiographic success (<30% residual stenosis, TIMI-3) was attained in 73% of SVGs and 87% of native coronary procedures. Distal embolization occurred in 13 cases, and was less likely to occur in patients treated with abciximab (0%) compared with patients treated with other glycoprotein IIb/IIIa blockers or heparin alone (17%, p = 0.02). A favorable response to the AngioJet (odds ratio 3.9) and freedom from embolization (odds ratio 14.6) were associated with a higher procedural success rate. In-hospital and long-term clinical outcomes were favorable. Thus, rheolytic thrombectomy resulted in significant reduction of the thrombus burden in most patients, restored TIMI-3 flow, and led to favorable short- and long-term outcomes.
Age Factors↗
The nondirected live-kidney donor: ethical considerations and practice guidelines: A National Conference Report.
BACKGROUND: The success of kidney transplantation from a genetically unrelated living spouse or friend has influenced transplant physicians to consider the requests of individuals wishing to volunteer to be a kidney donor who have no intended recipient specified. Representatives of the transplant community gathered in Boston, MA, on May 31, 2001, to deliberate on the experience of live kidney donation from such volunteers, currently termed nondirected donors (NDD). OBJECTIVE OF CONFERENCE PARTICIPANTS: The objective of the conference was to recommend ethical and practice guidelines for health care professionals considering the transplantation of a kidney from a live NDD. CONFERENCE PARTICIPANTS: This conference was convened under the sponsorship of The National Kidney Foundation, with representation from The American Society of Transplantation and The American Society of Transplant Surgeons, The American Society of Nephrology, The United Resource Networks, The United Network for Organ Sharing, The Association of Organ Procurement Organizations, The National Institutes of Health, and The Division of Transplantation of the Health Resources and Services Administration (see Appendix). CONFERENCE REPORT: The suggested content of screening interviews, which provide information regarding the donation process, elicits pertinent medical and psychosocial history, and assesses NDD motivation are presented in this report. Approaches to identifying the center that would evaluate the suitability of the NDD, to performing the kidney recovery, and to selecting the NDD recipient are also proposed. Other ethical issues such as the use of prisoners as an NDD, compensation for the NDD, media involvement, and communication between the NDD and recipient are discussed. CONCLUSION: The willingness of health care professionals to consider NDD volunteers is driven by the compelling need to provide organs for an ever-expanding list of patients awaiting a kidney transplant. However, the psychological impact and emotional reward of donation has yet to be determined for NDD who may not have any relationship to the recipient or knowledge of the recipient's outcome. Transplant centers that accept NDD should document an informed consent process that details donor risks, assures donor safety, and determines that the goals and expectations of the NDD and the recipient can be realized.
Communication↗
Cost-effectiveness of gamma radiation for treatment of in-stent restenosis: results from the Gamma-1 trial.
BACKGROUND: Recently, several randomized trials have demonstrated that intracoronary brachytherapy can reduce the rates of both angiographic and clinical restenosis in patients undergoing percutaneous coronary intervention (PCI) for in-stent restenosis. Whether this practice is cost-effective is unknown. METHODS AND RESULTS: Between December 1997 and July 1998, 252 patients with in-stent restenosis were randomized to receive brachytherapy or placebo after successful PCI as part of the Gamma-1 trial. We collected detailed resource utilization and cost data for each patient's initial hospitalization and for 1 year after randomization. Compared with conventional treatment, intracoronary brachytherapy increased procedure duration, physician services, and equipment costs. As a result, initial costs were increased by nearly $4100 per patient ($15 724 versus $11 675, P<0.001). Over the 1-year follow-up period, brachytherapy reduced the need for repeat revascularization by 21% and reduced the need for bypass surgery by 44%. Although follow-up medical care costs were $2200/patient lower with brachytherapy, total costs remained higher at 1 year ($28 543 versus $26 737, P=0.46). In a sensitivity analysis that incorporated recent technical modifications and the use of prolonged antiplatelet therapy to prevent late thrombotic occlusion, follow-up cost savings increased to $3600/patient, and 1-year costs were slightly lower with brachytherapy ($26 352 versus $26 729, P=0.87). Subgroup analysis demonstrated significant cost savings in patients with diabetes and patients who did not undergo repeat stenting. CONCLUSIONS: As performed in the Gamma-1 trial, coronary brachytherapy for in-stent restenosis improved clinical outcomes but increased 1-year costs compared with standard therapy. If late thrombosis can be eliminated, however, this technology has the potential to reduce overall medical care costs.
Angioplasty, Balloon, Coronary↗
Impact of clinical syndrome acuity on the differential response to 2 glycoprotein IIb/IIIa inhibitors in patients undergoing coronary stenting: the TARGET Trial.
BACKGROUND: Although glycoprotein IIb/IIIa inhibitors have been shown to reduce periprocedural and late ischemic events in patients undergoing stent implantation, the relative safety and efficacy of different agents in this class is less established. Also unknown is whether the acuity of the presenting clinical syndrome, which may affect the degree of platelet inhibition required or achieved, influences the response to different antiplatelet agents. METHODS AND RESULTS: A prospective, multicenter, double-blind, randomized trial was performed in which 4809 patients undergoing planned stenting were randomized to receive abciximab or tirofiban. In patients with acute coronary syndromes (ACS; n=3025), abciximab resulted in lower rates of myocardial infarction at 30 days (5.8% versus 8.5%; P=0.004) and 6 months (7.2% versus 9.8%; P=0.013), although 6-month mortality rates were identical (1.39% in both groups; P=0.99). Conversely, in patients without ACS (n=1784), myocardial infarction rates were not significantly lower with tirofiban, survival was similar, and target vessel revascularization was reduced, which translated into a trend toward enhanced 6-month event-free survival with tirofiban (89.7% versus 86.6%; P=0.056). CONCLUSIONS: In patients with ACS undergoing stent implantation, abciximab use compared with tirofiban results in greater suppression of periprocedural myonecrosis, although a survival benefit has not been demonstrated. Patients with stable coronary syndromes may have equivalent or better outcomes with tirofiban relative to abciximab, with fewer adverse hematologic and hemorrhagic events. These data raise important issues regarding the relative pharmacodynamic inhibition of platelet function required in varying clinical scenarios and have important implications for the cost-effective utilization of glycoprotein IIb/IIIa inhibitors.
Abciximab↗
Safety of subxyphoid pericardial access using a blunt-tip needle.
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Catheters, Indwelling↗
Angiotensin converting enzyme inhibition in chronic allograft nephropathy.
BACKGROUND: Although angiotensin-converting enzyme inhibition has been shown to slow progression of chronic allograft nephropathy in animal models, no studies have examined its efficacy in humans. METHODS: We retrospectively analyzed 63 patients with biopsy-proven chronic allograft nephropathy who had > or =6 months dialysis-free follow-up at our institution. A total of 32 patients treated for > or =6 consecutive months with angiotensin-converting enzyme inhibition and/or angiotensin-receptor blocker (ARB) therapy (group 1) were compared with 31 patients not on these agents (group 2). RESULTS: Except for a higher incidence of hypertension (100 vs. 78%, P=0.005) in group 1, there were no significant differences in baseline clinical characteristics at time of biopsy. With a mean follow-up time of 27 months in both groups, 6 of 32 (19%) group 1 patients vs. 12 of 31 (39%) group 2 reached the primary endpoint of > or =50% increase in serum creatinine (P=0.10). Mean time to primary endpoint was 46.6 months in group 1 vs. 32.7 months in group 2 (P=0.07). Three of 32 (9%) of group 1 patients vs. 8 of 31 (26%) of group 2 returned to dialysis during this time (P=0.11). Significantly fewer patients in group 1 reached the combined secondary endpoint of allograft failure or death (9.4 vs. 35.5%, P=0.01); in addition, group 1 had a longer mean time to this endpoint (51.2 vs. 37.6 months, P=0.03). On multivariate analysis, the only predictor of progression to primary endpoint was a high baseline serum creatinine (P=0.02). No significant differences in hyperkalemia or anemia were found between the two groups. CONCLUSIONS: Angiotensin-converting enzyme inhibition/angiotensin-receptor blocker therapy is well tolerated in renal allograft recipients with chronic allograft nephropathy. It is associated with a trend of slowing renal insufficiency as well as a significant survival benefit in the combined endpoint of allograft failure or death.
Adult↗
Long-term efficacy of platelet glycoprotein IIb/IIIa integrin blockade with eptifibatide in coronary stent intervention.
CONTEXT: In the Enhanced Suppression of the Platelet IIb/IIIa Receptor with Integrilin Therapy (ESPRIT) trial, treatment with eptifibatide, a platelet glycoprotein IIb/IIIa integrin blocker, was found to reduce the ischemic complications of nonurgent coronary stent implantation at 48 hours and 30 days. OBJECTIVE: To determine whether eptifibatide treatment continues to provide durable, long-term benefit after coronary stent intervention. DESIGN AND SETTING: The ESPRIT trial was a randomized, double-blind, placebo-controlled, parallel-group, crossover-permitted trial conducted from June 1999 through February 2000 at 92 tertiary care centers in the United States and Canada. PARTICIPANTS: A total of 2064 patients scheduled to undergo nonurgent percutaneous coronary intervention with stent implantation. INTERVENTION: Patients were randomly assigned to receive placebo (n = 1024) or eptifibatide (two 180-microg/kg boluses, 10 minutes apart, with a continuous infusion of 2.0 microg/kg per minute; n = 1040), started immediately before stent implantation and continued for 18 to 24 hours. Patients also received aspirin, heparin, and a thienopyridine. MAIN OUTCOME MEASURES: Composite rates of death or myocardial infarction (MI) and death, infarction, or target vessel revascularization during the 12 months after enrollment. RESULTS: Complete follow-up data were available for 988 patients given eptifibatide (95.0%) and 976 patients given placebo (95.3%). By 12 months, the composite of death or MI had occurred in 8.0% of eptifibatide-treated patients and in 12.4% of placebo-treated patients (hazard ratio [HR], 0.63; 95% confidence interval [CI], 0.48-0.83; P =.001). The composite rate of death, MI, or target vessel revascularization was 17.5% in eptifibatide-treated patients vs 22.1% in placebo-treated patients (HR, 0.76; 95% CI, 0.63-0.93; P =.007). CONCLUSIONS: Long-term outcomes of nonurgent coronary stent implantation appear to be improved through blockade of the platelet glycoprotein IIb/IIIa integrin with eptifibatide.
Aged↗