Early technology review: towards an expedited pathway.

OBJECTIVES: Evidence development for medical devices is often focused on satisfying regulatory requirements with the result that health professional and payer expectations may not be met, despite considerable investment in clinical trials. Early engagement with payers and health professionals could allow companies to understand these expectations and reflect them in clinical study design, increasing chances of positive coverage determination and adoption into clinical practice. METHODS: An example of early engagement through the EXCITE International model using an early technology review (ETR) is described which includes engagement with payers and health professionals to better inform companies to develop data that meet their expectations. ETR is based on an early evidence review, a framework of expectations that guides the process and identified gaps in evidence. The first fourteen ETRs were reviewed for examples of advice to companies that provided additional information from payers and health professionals that was thought likely to impact on downstream outcomes or strategic direction. Given that limitations were imposed by confidentiality, examples were genericized. RESULTS: Advice through early engagement can inform evidence development that coincides with expectations of payers and health professionals through a structured, objective, evidence-based approach. This could reduce the risk of business-related adverse outcomes such as failure to secure a positive coverage determination and/or acceptance by expert health professionals. CONCLUSIONS: Early engagement with key stakeholders exemplified by the ETR approach offers an alternative to the current approach of focusing on regulatory expectations. This could reduce the time to reimbursement and clinical adoption and benefit patient outcomes and/or health system efficiencies.

Transcatheter valve therapy registry is a model for medical device innovation and surveillance.

Heart valve diseases are increasingly prevalent, especially in people older than age seventy. Many of these elderly people have other comorbid conditions, making them poor candidates for surgical treatment of heart valve diseases. Since 2011 such patients have been eligible to receive new nonsurgical heart valve treatments approved by the Food and Drug Administration (FDA) and covered by Medicare. This article examines the Transcatheter Valve Therapy Registry, which captures clinical information on all US patients undergoing new nonsurgical heart valve treatments. The registry has patient-level data from more than 27,000 patients treated with the novel devices. Patient- and procedure-related data are gathered from hospitals, patient-reported outcomes are assessed pre- and postprocedure, and longer-term data on mortality and repeat hospitalization are provided by linking the registry's data to Medicare patient data. The registry is a model of collaboration among professional societies, the FDA, the Centers for Medicare and Medicaid Services, hospitals, patients, and the medical device industry. It has been used to support Medicare coverage decisions, expand device indications, provide comprehensive device surveillance, and establish national quality benchmarks. Beyond having it serve as a collaborative model, future goals for the registry include shortening the FDA-approval timeline for devices, providing data for decision-making tools for patients, and public reporting of hospital performance.

The reporting of blinding in physical medicine and rehabilitation randomized controlled trials: a systematic review.

OBJECTIVE: To conduct a systematic review evaluating the reporting of blinding in randomized controlled trials published in the field of Physical Medicine and Rehabilitation over two time periods. DATA SOURCES: We searched MEDLINE via PubMed for all randomized controlled trials published in American Journal of Physical Medicine and Rehabilitation, Archives of Physical Medicine and Rehabilitation, Clinical Rehabilitation, Disability and Rehabilitation and (Scandinavian) Journal of Rehabilitation Medicine in the years 2000 and 2010. STUDY SELECTION: We initially identified 222 articles, and 139 (62.6%) met our selection criteria. DATA EXTRACTION: Two independent investigators collected data regarding study characteristics and blinding from each article. Consistency of data extraction was evaluated. DATA SYNTHESIS: When comparing articles from 2010 and 2000, the former showed significantly higher rates for reporting of blinding, explicitly describing key persons' blinding status, and discussing the absence of blinding as a study limitation. There was a trend for lower reporting among trials with positive outcomes. No improvement was observed in other CONSORT-enforced parameters. CONCLUSIONS: Although the reporting of blinding in Physical Medicine and Rehabilitation randomized controlled trials shows some improvement over the past decade, it still does not fulfill current recommendations. Given its critical role in determining internal validity, stricter enforcement of CONSORT guidelines is needed.

Rationale and design of the MASS COMM trial: A randomized trial to compare percutaneous coronary intervention between MASSachusetts hospitals with cardiac surgery on-site and COMMunity hospitals without cardiac surgery on-site.

BACKGROUND: Emergency surgery has become an increasingly rare event after percutaneous coronary intervention (PCI). There have been no randomized trials evaluating whether cardiac surgery services on-site are essential for patient safety and optimal outcomes during and after PCI. STUDY DESIGN: The MASS COMM trial (ClinicalTrials.gov no. NCT01116882) is a randomized trial comparing the safety and effectiveness of nonemergency PCI at hospitals without surgery on-site (SOS) (non-SOS hospitals) and hospitals with SOS (SOS hospitals). A total of 3,690 subjects will be randomized in a 3:1 fashion to undergo PCI at non-SOS and SOS hospitals, with follow-up at hospital discharge, 30 days, and 12 months after PCI. The rate of major adverse cardiac events (all-cause mortality, myocardial infarction, repeat revascularization, and stroke) will serve as the primary safety end point at 30 days and the primary effectiveness end point at 12 months. The design is a 1-way randomized trial with a statistical hypothesis of noninferiority of nonemergency PCI at non-SOS hospitals for both safety and effectiveness end points. CONCLUSIONS: This multicenter, randomized trial will compare the relative safety and effectiveness of nonemergency PCI at sites with and without cardiac SOS.

Relative spatial distributions of coronary artery bypass graft insertion and acute thrombosis: a model for protection from acute myocardial infarction.

BACKGROUND: Randomized trials have demonstrated coronary artery bypass surgery (CABG) to be superior to percutaneous coronary intervention with respect to long-term mortality and morbidity from myocardial infarction within specific high-risk cohorts. The purpose of this study was to analyze the spatial distribution of coronary artery bypass graft anastomoses relative to acute thromboses in native coronary arteries. We hypothesized that insertion sites of bypass grafts are located distal to sites of acute thrombosis and consequently decrease cardiac morbidity and mortality associated with plaque rupture. METHODS: We analyzed 168 patients with prior CABG and 208 patients with ST-segment elevation myocardial infarctions (STEMI) presenting to the Brigham and Women's Hospital who underwent coronary angiography. We constructed a spatial map of the coronary arterial bypass graft insertion sites and compared these locations to sites of acute thrombosis leading to STEMI. RESULTS: Graft insertion sites were consistently located distal to acute thrombosis sites (left anterior descending artery median graft insertion versus median thrombosis site = 72 versus 34 mm, right coronary artery 91 versus 42 mm, left circumflex artery 44 versus 37 mm). Greater than 97% of thrombosis sites were located proximal to 75% of graft insertion sites. CONCLUSIONS: Coronary arterial bypass grafts provide the coverage of anatomic zones at risk for STEMI. The superior performance of CABG in high risk patients may be attributed to targeting of proximal coronary locations where thrombosis risk is clustered.

Lack of association between migraine headache and patent foramen ovale: results of a case-control study.

BACKGROUND: Clinical observations of migraine headache symptoms in patients with a patent foramen ovale (PFO), both of which conditions are highly prevalent, have raised the question of a possible pathophysiological relationship. We sought to evaluate the assumption of an association between migraine headaches and the presence of PFO by use of a large case-control study. METHODS AND RESULTS: We conducted a case-control study to assess the prevalence of PFO in subjects with and without migraine. Case subjects were those with a history of migraine (diagnosed by neurologists at a specialty academic headache clinic). Control subjects were healthy volunteers without migraine 1:1 matched on the basis of age and sex with case subjects. Presence of PFO was determined by transthoracic echocardiogram with second harmonic imaging and transcranial Doppler ultrasonography during a standardized procedure of infused agitated saline contrast with or without Valsalva maneuver and a review of the results by experts blinded to case-control status. PFO was considered present if both studies were positive. Odds ratios were calculated with conditional logistic regression in the matched cohort (n=288). In the matched analysis, the prevalence of PFO was similar in case and control subjects (26.4% versus 25.7%; odds ratio 1.04, 95% confidence interval 0.62 to 1.74, P=0.90). There was no difference in PFO prevalence in those with migraine with aura and those without (26.8% versus 26.1%; odds ratio 1.03, 95% confidence interval 0.48 to 2.21, P=0.93). CONCLUSIONS: We found no association between migraine headaches and the presence of PFO in this large case-control study.

Location of acute coronary artery thromboses in patients with and without chronic kidney disease.

Patients with chronic kidney disease have high rates of myocardial infarction and death following an initial attack. Proximal location of coronary atherosclerotic lesions has been linked to the risk of acute myocardial infarction and to infarction-associated mortality. To examine if the spatial distribution of lesions differs in patients with and without chronic kidney disease, we used quantitative coronary angiography to measure this in patients with acute coronary thromboses who were having angiography following acute myocardial infarction. Multivariable linear regression was used to adjust for differences in baseline characteristics. Among 82 patients with stage 3 or higher chronic kidney disease, 55.6% of lesions were located within 30 mm and 87.7% were within 50 mm of the coronary ostia. This compared to 34.7 and 71.8%, respectively, among 299 patients without significant kidney disease. Chronic kidney disease was independently and significantly associated with a 7.0 mm decrease in the distance from the coronary ostia to the problem lesion. Our study suggests that a causal link between a more proximal culprit lesion location in patients with chronic kidney disease and their high mortality rates after myocardial infarct is possible and may have important implications for interventions to prevent infarction.

Saphenous vein graft stenting and major adverse cardiac events: a predictive model derived from a pooled analysis of 3958 patients.

BACKGROUND: Treatment of saphenous vein graft (SVG) stenosis with percutaneous coronary intervention has a 15% to 20% incidence of major adverse cardiac events (MACE) within 30 days. Although MACE rates are reduced significantly by the use of embolic protection devices (EPDs), neither the level of baseline risk nor the benefit provided by EPDs has been well characterized. METHODS AND RESULTS: Data from 5 randomized controlled trials and 1 registry evaluating EPDs in SVG percutaneous coronary intervention (n=3958 patients) were pooled for analysis. MACE was defined as a composite of death, myocardial infarction, and target vessel revascularization. Baseline variables and 2 summary angiographic variables (an SVG degeneration score and an estimate of lesion plaque volume) were included in a multivariable logistic regression model to predict 30-day MACE, with adjustment for the type of device used and inter-study variation. The angiographic variables were potent predictors of MACE (increasing SVG degeneration score, P<0.0001; larger estimated plaque volume, P<0.0001), with significant contributions from the presence of thrombus (P<0.01), increasing patient age (P<0.01), glycoprotein IIb/IIIa inhibitor use (P=0.02), and current tobacco abuse (P=0.03). The treatment benefit of EPDs was preserved across all categories of risk as categorized by SVG degeneration or plaque volume. CONCLUSIONS: The strongest predictors of 30-day MACE in SVG percutaneous coronary intervention are angiographic estimates of plaque volume and SVG degeneration. Identification of these predictors of 30-day MACE allows reliable prediction of patient outcomes and confirms consistent treatment benefit with the use of EPDs across the range of patients tested in randomized trials.

Zotarolimus-eluting stents in patients with native coronary artery disease: clinical and angiographic outcomes in 1,317 patients.

Early studies of a cobalt-based alloy stent coated with the novel antiproliferative agent zotarolimus and a phosphorylcholine polymer have demonstrated significant reductions in angiographic restenosis and target vessel revascularization compared with bare metal stents. However, the generalizability of the angiographic outcomes and clinical benefit of zotarolimus-eluting stents (ZESs) to a more real-world patient population is undetermined. Clinical and angiographic outcomes in 1,317 patients treated with the ZES in the first 4 trials of the Endeavor ZES (Medtronic Vascular, Santa Rosa, CA) clinical trials program were pooled for systematic analysis. Protocol-specified follow-up angiography was performed at 8 or 12 months for a subset of 750 of these patients, and clinical follow-up was performed at 9 months after the index procedures in all patients. Diabetes mellitus was present in 22.5% of patients, the mean reference vessel diameter was 2.73 mm, and the mean lesion length was 14.59 mm. At 8 months (12 months for ENDEAVOR I), mean +/- SD in-stent late luminal loss was 0.61 +/- 0.49 mm. In-stent late luminal loss was greatest in larger caliber (>2.9 mm) vessels (0.65 +/- 0.49 mm) and longer (>16.3 mm) lesions (0.70 +/- 0.52 mm) but did not statistically vary according to diabetic status. At 9 months, overall rates of target lesion revascularization (TLR) and major adverse cardiac events (MACE) were 4.9% and 7.7%, respectively. The rate of TLR at 12 months was not significantly different relative to diabetes and lesion length >16.3 mm (7.2% and 7.7%, respectively), although TLR was significantly more common when reference vessel diameter was <2.5 mm (8.5%; p = 0.013). At 24 months, overall rates of TLR and MACE were 6.5% and 9.9%, respectively. The overall 24-month rate of stent thrombosis was 0.3%, with no events occurring >14 days after the procedure. Despite varied clinical and angiographic characteristics, treatment with the ZES is associated with consistently low rates of TLR and overall major adverse events, including stent thrombosis. Although these findings indicate the efficacy and safety of the ZES over the time course of the first 4 ENDEAVOR clinical trials, additional ongoing study with more open patient inclusion criteria (including long lesions, small vessels, bifurcations, etc) will be important for discerning whether comparable clinical outcomes can be extended to lesion subsets of higher complexity.

Understanding the drug-eluting stent trials.

The advent of intravascular stenting dramatically reduced the incidence of restenosis among patients undergoing percutaneous transluminal coronary angioplasty. However, a substantial percentage of patients, particularly those with risk factors such as diabetes mellitus or complicated lesions, remain at risk for restenosis. Drug-eluting stents overcome this problem by releasing bioactive agents from a polymeric coating directly into the vessel wall, inhibiting the cellular mechanisms of restenosis while avoiding systemic toxicity. Recent data indicate that local targeting of the proliferative process with drug-eluting stents dramatically reduces the risk for restenosis, even among high-risk patients. A range of bioactive coatings are currently available or in late clinical trials. Both sirolimus- and paclitaxel-eluting stents have demonstrated efficacy in a broad range of patient types; early data from clinical trials of second-generation stent coatings, such as everolimus and ABT-578 (zotarolimus), suggest that these agents are also effective in preventing restenosis. This article reviews the pathophysiology of in-stent restenosis and surveys recent key clinical trials of drug-eluting stents.

The SIRIUS-DIRECT trial: a multi-center study of direct stenting using the sirolimus-eluting stent in patients with de novo native coronary artery lesions.

OBJECTIVE: To assess the safety and efficacy of direct stenting using the sirolimus-eluting BX Velocitytrade mark stent in patients with coronary lesions. BACKGROUND: Although direct coronary stenting has become a widespread practice, there have been no systematic assessments of direct stenting with drug-eluting stents. METHODS: Total of 225 patients with identical inclusion and exclusion criteria as the original SIRIUS trial were enrolled in this prospective single-arm study. They were compared in a no-inferiority design with 412 similar patients from the SIRIUS trial who had sirolimus-eluting stents deployed after predilatation and were preassigned to angiographic follow-up evaluation. RESULTS: Direct stenting was successful in 85.8% of the patients. Compared with the predilatation group, direct stenting was associated with shorter median procedure duration (33 min vs. 45 min, P < 0.001). Angiographic follow-up at 8 months revealed similar late loss (in-stent-0.19 +/- 0.47 mm vs. 0.17 +/- 0.44 mm, and in-lesion-0.23 +/- 0.41 mm vs. 0.24 +/- 0.47 mm) and similar frequency of binary restenosis (in-stent-4.6% vs. 3.2% and in-lesion-6.1% vs. 8.9%) between the two treatment strategies. However, stent-edge restenosis was lower with direct stenting than in the predilatation control group (2.1% vs. 6.9%, P = 0.02). At 12-months, there were no significant differences in target lesion revascularization (3.7% vs. 5.1%, P = ns) or composite major adverse cardiac events (7.0% vs. 8.3%, P = ns). CONCLUSIONS: In patients similar to those treated in the SIRIUS trial, direct stenting using sirolimus-eluting stents achieves excellent short- and long-term clinical and angiographic results with shorter procedure time and less frequent stent edge restenosis compared with predilation stent implantation techniques.

Detailed intravascular ultrasound analysis of Zotarolimus-eluting phosphorylcholine-coated cobalt-chromium alloy stent in de novo coronary lesions (results from the ENDEAVOR II trial).

Zotarolimus-eluting phosphorylcholine-coated cobalt-chromium alloy Driver stents (ZES) demonstrated significant reductions in target lesion revascularization rate with few apparent adverse events compared with bare metal stents (BMS; uncoated Driver stents) in a prospective, multicenter, double-blind, randomized controlled trial in de novo coronary lesions. The aim of this study was to examine detailed vascular responses to ZES compared with BMS using serial intravascular ultrasound analysis. A total of 343 patients (ZES n = 178, BMS n = 165) were enrolled in this formal, prespecified intravascular ultrasound substudy of the Randomized Controlled Trial to Evaluate the Safety and Efficacy of the Medtronic AVE Zotarolimus-Eluting Driver Coronary Stent in de Novo Native Coronary Artery Lesions (ENDEAVOR II), a prospective, multicenter, double-blind, randomized controlled trial to compare ZES and BMS in de novo native coronary artery lesions. Quantitative and qualitative intravascular ultrasound analyses were performed postprocedurally and at 8-month follow-up in stented and reference segments. ZES showed significantly less neointima, with a larger lumen than BMS at 8 months (percentage neointimal volume 17.6 +/- 10.1% vs 29.4 +/- 17.2%, p <0.0001; maximum percentage neointimal area 32.9 +/- 13.0% vs 47.6 +/- 18.6%, p <0.0001; minimum luminal area 4.9 +/- 1.6 vs 4.0 +/- 1.7 mm(2), p <0.0001) and no unfavorable edge effect. In the 18-mm single stents, ZES showed evenly inhibited neointima compared with BMS. Neither persistent stent-edge dissection nor late-acquired incomplete stent apposition was observed in either group. In conclusion, ZES showed evenly inhibited neointima with no apparent adverse vascular response in stented and reference segments at 8 months compared with BMS.

Safety of sirolimus-eluting stenting and its effect on restenosis in patients with unstable angina pectoris (a SIRIUS substudy).

The SIRIUS study was a double-blinded, randomized trial of the sirolimus-eluting stent (SES) to evaluate its effect on the rate of restenosis. The present report is a retrospective analysis of short- and long-term outcomes of SESs compared with bare metal stents (BMSs) in a subgroup of patients with unstable angina enrolled in the trial. Of 1,058 patients randomized in SIRIUS, 533 (50.4%) had unstable angina pectoris and 490 had stable angina. In the unstable angina group, patients treated with SESs and BMSs had similar clinical and angiographic characteristics. The stenting procedure was highly successful in the 2 groups (95.9% and 97.4%, respectively) with similar immediate angiographic results and short-term (in-hospital) clinical event rates. At 1-year follow-up, compared with BMSs, patients with unstable angina treated with SESs had significantly lower rates of target lesion revascularization (5.5% vs 22.3%, p <0.0001), target vessel failure (10.9% vs 26.3%, p <0.0001), and major adverse cardiac events (8.4% vs 24.8%, p <0.0001). Stent thrombosis was a rare event, with only 1 patient (0.4%) in each group during the first 30 days. Late thrombosis occurred in 2 patients (0.7%) in the BMS group but in none of the SES group. In conclusion, in the higher risk subgroup of patients with unstable angina, SESs are as safe as BMSs in decreasing restenosis and the need for repeat revascularization. This is reflected by a significant decrease in major adverse cardiac events and target vessel failure. Patients with unstable angina undergoing percutaneous coronary intervention who meet the entry criteria of the SIRIUS study should be preferentially treated with SESs.

Regions of low endothelial shear stress are the sites where coronary plaque progresses and vascular remodelling occurs in humans: an in vivo serial study.

AIM: We performed serial intracoronary studies of patients with stable coronary artery disease (CAD) to investigate the relationships among baseline endothelial shear stress (ESS), CAD progression, and vascular remodelling. Local haemodynamic factors are critical determinants of plaque progression, vascular remodelling, and clinical CAD manifestations. METHODS AND RESULTS: The 3-D anatomy of coronary arteries with lumen obstruction <50% was determined by fusing intracoronary ultrasound and angiographic images in 13 patients at baseline and 8 +/- 2 months later. Cross-sectional area of plaque, lumen, and external elastic membrane (EEM), and coronary flow were measured. Local ESS was calculated. Subsegments with similar ESS were categorized based on low (<12 dynes/cm(2)) and moderate/higher ESS (> or =12 dynes/cm(2)). There were 47 subsegments of similar baseline ESS: nine with low ESS and 38 with moderate/higher ESS. Median subsegment length was 6.9 mm (25th-75th percentiles = 4.2-12.0), and median area of similar ESS of 52.6 mm(2) (25th-75th percentiles = 26.9-88.0). Subsegments with low ESS exhibited plaque progression when compared with subsegments with moderate/higher ESS (33.3% vs. 7.9%, respectively, P = 0.009 adjusted for clustering of lesions within patients) and constrictive remodelling (44.0% vs. 5.3%, respectively, P = 0.16 adjusted for clustering of lesions within patients). Expansive remodelling occurred with similar frequency in subsegments with low vs. moderate/higher baseline ESS. CONCLUSION: Plaque progresses in subsegments with low ESS, associated with either constrictive or expansive remodelling. Different mechanisms are likely responsible for expansive remodelling in different local vascular environments. Early in vivo identification of arterial subsegments likely to develop high-risk plaque characteristics may allow for selective interventions to avoid adverse cardiac outcomes.

Distribution of coronary artery disease and relation to mortality in asymptomatic hemodialysis patients.

BACKGROUND: Long-term dialysis patients have a high incidence of myocardial infarction and cardiovascular death, but the incidence of coronary artery disease (CAD) in asymptomatic patients, distribution of coronary obstruction, and relationship between lesion location and mortality are unknown. METHODS: We studied 67 asymptomatic hemodialysis patients who volunteered for coronary angiography. Coronary stenoses of 50% or greater were documented, and the location of each within the proximal, midportion, or distal segment of the coronary vessel was recorded. Patients were followed up until death or renal transplantation. Cox proportional hazards regression was performed to analyze the relationship of lesion location with mortality. RESULTS: Obstructive CAD was common. Twenty-eight subjects (41.7%) had 50% or greater stenosis in at least 1 epicardial vessel, and 19 subjects (28.5%) had evidence of CAD within the proximal third of an epicardial vessel. After a median follow-up of 2.7 years, the presence of proximal CAD was associated with a marked increase in risk of death (adjusted hazard ratio, 3.14; 95% confidence interval, 1.34 to 7.33; P = 0.008) and was associated more strongly with mortality than multivessel disease or left anterior descending disease. CONCLUSION: CAD is common in asymptomatic dialysis patients, and stenoses frequently are located within the proximal coronary arteries, where they are associated with markedly increased risks of death. Additional studies are needed to determine whether proximal disease is a modifiable risk factor for cardiovascular mortality in dialysis patients.

Risks of coronary artery bypass surgery in dialysis-dependent patients--analysis of the 2001 National Inpatient Sample.

BACKGROUND: Dialysis patients have a high risk of cardiovascular death but may under-use coronary artery bypass grafting (CABG) because of the risk of peri-operative death. Whether operative mortality in dialysis patients has declined with contemporary techniques is uncertain. We undertook this study in order to compare peri-operative mortality in chronic dialysis (CD) and non-dialysis patients following CABG and to determine whether high levels of comorbidity in CD patients account for identified differences in operative risk. METHODS: This study is a retrospective analysis of the 2001 National Inpatient Sample, a stratified probability sample of over seven million admissions in 33 states. Administrative data and ICD-9CM codes were used to identify dialysis patients, comorbidities, procedures and operative outcomes. Multivariable logistic regression was used to adjust for confounding. RESULTS: In this study, 77 323 non-dialysis patients and 635 dialysis patients underwent CABG. In-hospital death occurred in 11.1% of dialysis patients compared to 3.4% of non-dialysis patients. Rates of stroke, sepsis and pneumonia were also increased in dialysis patients. After adjustment for other surgical risk factors, the odds of in-hospital death were 3.38 (2.54-4.50, P < 0.001) times higher in dialysis than non-dialysis patients. CONCLUSIONS: Operative mortality in dialysis patients remains high despite recent advances in CABG surgery and is not explained by the high rates of comorbidity in dialysis patients. Because there is a very high risk of cardiovascular death without intervention, CABG may nevertheless be a life-saving therapy in CD patients. Randomized trials are needed to better define the optimal role of CABG in dialysis patients.