Thomas P. Gross

Association Between Endoscopic vs Open Vein-Graft Harvesting and Mortality, Wound Complications, and Cardiovascular Events in Patients Undergoing CABG Surgery

CONTEXT The safety and durability of endoscopic vein graft harvest in coronary artery bypass graft (CABG) surgery has recently been called into question. OBJECTIVE To compare the long-term outcomes of endoscopic vs open vein-graft harvesting for Medicare patients undergoing CABG surgery in the United States. DESIGN, SETTING, AND PATIENTS An observational study of 235,394 Medicare patients undergoing isolated CABG surgery between 2003 and 2008 at 934 surgical centers participating in the Society of Thoracic Surgeons (STS) national database. The STS records were linked to Medicare files to allow longitudinal assessment (median 3-year follow-up) through December 31, 2008. MAIN OUTCOME MEASURES All-cause mortality. Secondary outcome measures included wound complications and the composite of death, myocardial infarction, and revascularization. RESULTS Based on Medicare Part B coding, 52% of patients received endoscopic vein-graft harvesting during CABG surgery. After propensity score adjustment for clinical characteristics, there were no significant differences between long-term mortality rates (13.2% [12,429 events] vs 13.4% [13,096 events]) and the composite of death, myocardial infarction, and revascularization (19.5% [18,419 events] vs 19.7% [19,232 events]). Time-to-event analysis for those patients receiving endoscopic vs open vein-graft harvesting revealed adjusted hazard ratios [HRs] of 1.00 (95% CI, 0.97-1.04) for mortality and 1.00 (95% CI, 0.98-1.05) for the composite outcome. Endoscopic vein-graft harvesting was associated with lower harvest site wound complications relative to open vein-graft harvesting (3.0% [3654/122,899 events] vs 3.6% [4047/112,495 events]; adjusted HR, 0.83; 95% CI, 0.77-0.89; P < .001). CONCLUSION Among patients undergoing CABG surgery, the use of endoscopic vein-graft harvesting compared with open vein-graft harvesting was not associated with increased mortality.

The US Food and Drug Administration's Sentinel Initiative: Expanding the horizons of medical product safety

Office of Medical Policy, Center for Drug Evaluation and Research, Food and Drug Administration, Silver Spring, MD 20993, USA Office of Surveillance and Biometrics, Center for Devices and Radiological Health, Food and Drug Administration, Silver Spring, MD 20993, USA Office of Biostatistics and Epidemiology, Center for Biologics Evaluation and Research, Food and Drug Administration, Rockville, MD 20852, USA Office of Surveillance and Epidemiology, Center for Drug Evaluation and Research, Food and Drug Administration, Silver Spring, MD 20993 USA Center for Biologics Evaluation and Research, Food and Drug Administration, Rockville, MD 20852, USA Center for Drug Evaluation and Research, Food and Drug Administration, Silver Spring, MD 20993, USA

Prevalence of latex-specific IgE antibodies in hospital personnel

BACKGROUND Rubber latex hypersensitivity is an important concern for health care workers. PURPOSE The Center for Devices and Radiological Health, in collaboration with the Consumer Product Safety Commission, conducted a multicenter study of the prevalence of latex-specific IgE antibodies among United States hospital personnel. MATERIALS AND METHODS Nine hospitals participated in the cross-sectional study. A total of 504 hospital personnel completed questionnaires that provided an array of demographic, occupational, and clinical information, including a history, if any, of allergies and the use of latex and nonlatex gloves. More than three-quarters (76.5%) of the participants were tested for total IgE and latex specific IgE. RESULTS A total of 21 (5.5%, 95% CI = 3%-7%) of the tested participants were positive for the presence of latex specific IgE antibodies, defined as a latex IgE level of > or = 0.6 ng/mL. Latex specific IgE antibodies were more prevalent in participants who reported tachycardia, palpitations, flushing, or wheezing associated with latex gloves (Odds Ratio = 10.2, 95% CI = 3.7-28.6). CONCLUSION The studys results suggest that the prevalence of latex-specific IgE antibodies among hospital personnel is appreciable and these personnel and their health care providers should be aware of this entity.

Prevalence and treatment of asthma in the Michigan Medicaid patient population younger than 45 years, 1980-1986.

The prevalence and outpatient treatment of asthma were studied in the Michigan Medicaid patient population by use of computerized physician, hospital, and pharmacy reimbursement data to mark and track asthma-related medical transactions. Asthma cases were defined as patients with evidence of at least two diagnoses and prescription drug transactions consistent with asthma. More than 52,000 cases were thus identified. The period prevalence of asthma was estimated on a year-by-year basis. The prevalence of asthma in the population increased from 2.0 per 100 Medicaid patients in 1980 to 2.8 per 100 Medicaid patients in 1986. Prevalence decreased with age until the age of 20 years and increased thereafter, and was higher in male children than in female children. In contrast, asthma was more prevalent in female adults than in male adults. Prevalence was higher in black subjects than in other races and higher in urban residents than in rural residents. The total number of reimbursements for antiasthma medications increased from 60,000 per year to 120,000 per year, and the average number of antiasthma prescriptions per Michigan Medicaid asthma case increased at the rate of 6.6% per year during the study interval. Changes in the preferred types of asthma treatment consistent with changes that have occurred in the general population were observed. These data suggest that the relative and absolute occurrence of asthma and asthma treatment in the Michigan Medicaid population is increasing.

Automated Surveillance to Detect Postprocedure Safety Signals of Approved Cardiovascular Devices

CONTEXT Ensuring the safety of medical devices challenges current surveillance approaches, which rely heavily on voluntary reporting of adverse events. Automated surveillance of clinical registries may provide early warnings in the postmarket evaluation of medical device safety. OBJECTIVE To determine whether automated safety surveillance of clinical registries using a computerized tool can provide early warnings regarding the safety of new cardiovascular devices. DESIGN, SETTING, AND PATIENTS Prospective propensity-matched cohort analysis of 7 newly introduced cardiovascular devices, using clinical data captured in the Massachusetts implementation of the National Cardiovascular Data Repository CathPCI Registry for all adult patients undergoing percutaneous coronary intervention from April 2003 through September 2007 in Massachusetts. MAIN OUTCOME MEASURE Presence of any safety alert, triggered if the cumulative observed risk for a given device exceeded the upper 95% confidence interval (CI) of comparator control device. Predefined sensitivity analyses assessed robustness of alerts when triggered. RESULTS We evaluated 74,427 consecutive interventional coronary procedures. Three of 21 safety analyses triggered sustained alerts in 2 implantable devices. Patients receiving Taxus Express2 drug-eluting stents experienced a 1.28-fold increased risk of postprocedural myocardial infarction (2.87% vs 2.25%; absolute risk increase, 0.62% [95% CI, 0.25%-0.99%]) and a 1.21-fold increased risk of major adverse cardiac events (4.24% vs 3.50%; absolute increase, 0.74% [95% CI, 0.29%-1.19%]) compared with those receiving alternative drug-eluting stents. Patients receiving Angio-Seal STS vascular closure devices experienced a 1.51-fold increased risk of major vascular complications (1.09% vs 0.72%; absolute increased risk, 0.37% [95% CI, 0.03%-0.71%]) compared with those receiving alternative vascular closure devices. Sensitivity analyses confirmed increased risk following use of the Taxus Express2 stent but not the Angio-Seal STS device. CONCLUSION Automated prospective surveillance of clinical registries is feasible and can identify low-frequency safety signals for new cardiovascular devices.

A framework for evidence evaluation and methodological issues in implantable device studies.

Implantable medical devices (IMD) are frequently used in interventional medicine. There are a host of complex methodological issues to consider in conducting device studies. A general conceptual framework for evidence evaluation is needed to help investigators conduct comparative studies in this setting. It is known that clinical trials of implants require study design planning and creative execution that are quite different from those in pharmaceutical setting. Important study design issues such as randomization, masking and allocation concealment require unique approaches for each device. In addition, device comparative studies must cope with sources of variability different from pharmaceutical studies. These include operator learning curve effects, hospital-operator-patient interactions, and issues related to device technical characteristics. Observational studies of IMDs are particularly challenging. Selection of comparison groups, adjusting for confounding and addressing learning curve issues needs careful planning. We propose a general framework for IMD evaluation and provide an outline of the methodological issues that require further discussion. We hope this article will inspire and help to inform those interested in advancing comparative safety and effectiveness of IMDs and to plan and pursue future methodological work in this area.

Use and effectiveness of condoms during anal intercourse: a review.

Background and Objectives: Anal intercourse has been associated with a high risk of human immunodeficiency virus transmission. Survey data suggest that unprotected anal intercourse is practiced by a substantial proportion of the sexually active population, regardless of sexual orientation. Goal: To review the literature related to the use and effectiveness of condoms during anal intercourse, with emphasis on prevention of human immunodeficiency virus transmission. Study Design: Literature review. Results: Epidemiologic studies have shown that consistent, correct condom use reduces the overall risk of sexual transmission of human immunodeficiency virus. Evidence for the effectiveness of condoms used during anal intercourse is less definitive. Survey and clinical trials data indicate that condom breakage and slippage rates vary during anal intercourse and may be considerably higher than during vaginal intercourse. Although condoms designed for anal intercourse have been studied and marketed in Europe, data on their actual performance are scarce. In addition, no information exists on the effectiveness of polyurethane or other nonlatex condoms for use during anal intercourse. Conclusions: Development of newer and more effective condoms for use during anal intercourse requires consideration of the ethical issues involved in testing and marketing devices used during an activity that carries with it the potential for a substantial risk to health.

Sex and risk of hip implant failure: assessing total hip arthroplasty outcomes in the United States.

IMPORTANCE The role of sex in relationship to implant failure after total hip arthroplasty (THA) is important for patient management and device innovation. OBJECTIVE To evaluate the association of sex with short-term risk of THA revision after adjusting for patient, implant, surgery, surgeon, and hospital confounders. DESIGN AND SETTING A prospective cohort of patients enrolled in a total joint replacement registry from April 1, 2001, through December 31, 2010. PARTICIPANTS Patients undergoing primary, elective, unilateral THA. MAIN OUTCOME MEASURES Failure of THA, defined as revision procedure for (1) any reason, (2) septic reason, or (3) aseptic reason after the index procedure. RESULTS A total of 35,140 THAs with 3.0 years of median follow-up were identified. Women constituted 57.5% of the study sample, and the mean (SD) patient age was 65.7 (11.6) years. A higher proportion of women received 28-mm femoral heads (28.2% vs 13.1%) and had metal on highly cross-linked polyethylene-bearing surfaces (60.6% vs 53.7%) than men. Men had a higher proportion of 36-mm or larger heads (55.4% vs 32.8%) and metal on metal-bearing surfaces (19.4% vs 9.6%). At 5-year follow-up, implant survival was 97.4% (95% CI, 97.2%-97.6%). Device survival for men (97.7%; 95% CI, 97.4%-98.0%) vs women (97.1%; 95% CI, 96.8%-97.4%) was significantly different (P = .01). After adjustments, the hazards ratios for women were 1.29 (95% CI, 1.11-1.51) for all-cause revision, 1.32 (95% CI, 1.10-1.58) for aseptic revision, and 1.17 (95% CI, 0.81-1.68) for septic revision. CONCLUSIONS After considering patient-, surgery-, surgeon-, volume-, and implant-specific risk factors, women had a 29% higher risk of implant failure than men after THA in this community-based sample.

Risk of revision for fixed versus mobile-bearing primary total knee replacements.

BACKGROUND Mobile-bearing total knee arthroplasty prostheses were developed to reduce wear and revision rates; however, these benefits remain unproven. The purposes of this study were to compare the short-term survivorship and to determine risk factors for revision of mobile-bearing and fixed-bearing total knee replacements. METHODS A prospective cohort study of primary total knee arthroplasties performed from 2001 to 2009 was conducted with use of a community total joint replacement registry. Patient characteristics and procedure details were identified. Cox regression models were used. Bearing type was investigated as a risk factor for revision while adjusted for other risk factors such as age, American Society of Anesthesiologists (ASA) score, body mass index, sex, race, diagnosis, bilateral procedures, cruciate-retaining versus posterior-stabilized components, surgical approach, fixation, patellar resurfacing, hospital and surgeon volumes, and fellowship training. RESULTS The study cohort consisted of 47,339 total knee arthroplasties, with 62.6% of the procedures in women. Fixed bearings were used in 41,908 knees (88.5%) and mobile bearings in 4830 (10.2%). Rotating-platform designs were used in all mobile-bearing total knee arthroplasties (3112 had a Rotating-Platform Press-Fit Condylar posterior-stabilized design; 1053, a Low Contact Stress [LCS] design; and 665, a Rotating-Platform Press-Fit Condylar cruciate-retaining design). Patients who received fixed-bearing total knee arthroplasty systems were older (mean age, 68.1 years) than those who received mobile-bearing total knee arthroplasty systems (mean age, 62.2 years); the difference was significant (p < 0.001). Overall, 515 knees (1.1%) were revised for reasons other than infection. The survival rate was 97.8% (95% confidence interval [CI], 97.4% to 98.0%) at 6.7 years. The adjusted risk of aseptic revision for the LCS total knee replacements was 2.01 times (95% CI, 1.41 to 2.86) higher than that for fixed-bearing total knee replacements (p < 0.001).There was no significant revision risk for the other mobile-bearing total knee arthroplasty systems. There was no association with surgeon and hospital case volumes and the risk of revision total knee arthroplasty. CONCLUSIONS Our study suggests the benefit of potential long-term wear reduction with the LCS implant may not be realized in a community-based setting, where a variety of surgical skills, surgical experience, and diverse patient demographic factors may affect early outcomes. LEVEL OF EVIDENCE Therapeutic Level II.

Planning the Safety of Atrial Fibrillation Ablation Registry Initiative (SAFARI) as a Collaborative Pan-Stakeholder Critical Path Registry Model: A Cardiac Safety Research Consortium “Incubator” Think Tank

Atrial fibrillation (AF) is a major public health problem in the United States that is associated with increased mortality and morbidity. Of the therapeutic modalities available to treat AF, the use of percutaneous catheter ablation of AF is expanding rapidly. Randomized clinical trials examining the efficacy and safety of AF ablation are currently underway; however, such trials can only partially determine the safety and durability of the effect of the procedure in routine clinical practice, in more complex patients, and over a broader range of techniques and operator experience. These limitations of randomized trials of AF ablation, particularly with regard to safety issues, could be addressed using a synergistically structured national registry, which is the intention of the SAFARI. To facilitate discussions about objectives, challenges, and steps for such a registry, the Cardiac Safety Research Consortium and the Duke Clinical Research Institute, Durham, NC, in collaboration with the US Food and Drug Administration, the American College of Cardiology, and the Heart Rhythm Society, organized a Think Tank meeting of experts in the field. Other participants included the National Heart, Lung and Blood Institute, the Centers for Medicare and Medicaid Services, the Agency for Healthcare Research and Quality, the Society of Thoracic Surgeons, the AdvaMed AF working group, and additional industry representatives. The meeting took place on April 27 to 28, 2009, at the US Food and Drug Administration headquarters in Silver Spring, MD. This article summarizes the issues and directions presented and discussed at the meeting.