David J. Cohen

Hospital delays in reperfusion for ST-elevation myocardial infarction: implications when selecting a reperfusion strategy.

Background— It has been suggested that the survival benefit associated with primary percutaneous coronary intervention (PPCI) in ST-segment elevation myocardial infarction may be attenuated if door-to-balloon (DB) time is delayed by >1 hour beyond door-to-needle (DN) times for fibrinolytic therapy. Whereas DB times are rapid in randomized trials, they are often prolonged in routine practice. We hypothesized that in clinical practice, longer DB-DN times would be associated with higher mortality rates and reduced PPCI survival advantage. We also hypothesized that in addition to PPCI delays, patient risk factors would significantly modulate the relative survival advantage of PPCI over fibrinolysis. Methods and Results— DB-DN times were calculated by subtracting median DN time from median DB time at a hospital using data from 192 509 patients at 645 National Registry of Myocardial Infarction hospitals. Hierarchical models that adjusted simultaneously for both patient-level risk factors and hospital-level covariates were used to evaluate the relationship between PCI-related delay, patient risk factors, and in-hospital mortality. Longer DB-DN times were associated with increased mortality (P<0.0001). The DB-DN time at which mortality rates with PPCI were no better than that of fibrinolysis varied considerably depending on patient age, symptom duration, and infarct location. Conclusions— As DB-DN times increase, the mortality advantage of PPCI over fibrinolysis declines, and this advantage varies considerably depending on patient characteristics. As indicated in the American College of Cardiology/American Heart Association guidelines, both the hospital-based PPCI-related delay (DB-DN time) and patient characteristics should be considered when a reperfusion strategy is selected.

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.

Supervised Exercise Versus Primary Stenting for Claudication Resulting From Aortoiliac Peripheral Artery Disease Six-Month Outcomes From the Claudication: Exercise Versus Endoluminal Revascularization (CLEVER) Study

Background— Claudication is a common and disabling symptom of peripheral artery disease that can be treated with medication, supervised exercise (SE), or stent revascularization (ST). Methods and Results— We randomly assigned 111 patients with aortoiliac peripheral artery disease to receive 1 of 3 treatments: optimal medical care (OMC), OMC plus SE, or OMC plus ST. The primary end point was the change in peak walking time on a graded treadmill test at 6 months compared with baseline. Secondary end points included free-living step activity, quality of life with the Walking Impairment Questionnaire, Peripheral Artery Questionnaire, Medical Outcomes Study 12-Item Short Form, and cardiovascular risk factors. At the 6-month follow-up, change in peak walking time (the primary end point) was greatest for SE, intermediate for ST, and least with OMC (mean change versus baseline, 5.8±4.6, 3.7±4.9, and 1.2±2.6 minutes, respectively; P <0.001 for the comparison of SE versus OMC, P =0.02 for ST versus OMC, and P =0.04 for SE versus ST). Although disease-specific quality of life as assessed by the Walking Impairment Questionnaire and Peripheral Artery Questionnaire also improved with both SE and ST compared with OMC, for most scales, the extent of improvement was greater with ST than SE. Free-living step activity increased more with ST than with either SE or OMC alone (114±274 versus 73±139 versus −6±109 steps per hour), but these differences were not statistically significant. Conclusions— SE results in superior treadmill walking performance than ST, even for those with aortoiliac peripheral artery disease. The contrast between better walking performance for SE and better patient-reported quality of life for ST warrants further study. Clinical Trial Registration— URL: . Unique identifier: [NCT00132743][1]. # Clinical Perspective {#article-title-36} [1]: /lookup/external-ref?link_type=CLINTRIALGOV&access_num=NCT00132743&atom=%2Fcirculationaha%2F125%2F1%2F130.atomBackground Claudication is a common and disabling symptom of peripheral artery disease that can be treated with medication, supervised exercise or stent revascularization.Background— Claudication is a common and disabling symptom of peripheral artery disease that can be treated with medication, supervised exercise (SE), or stent revascularization (ST). Methods and Results— We randomly assigned 111 patients with aortoiliac peripheral artery disease to receive 1 of 3 treatments: optimal medical care (OMC), OMC plus SE, or OMC plus ST. The primary end point was the change in peak walking time on a graded treadmill test at 6 months compared with baseline. Secondary end points included free-living step activity, quality of life with the Walking Impairment Questionnaire, Peripheral Artery Questionnaire, Medical Outcomes Study 12-Item Short Form, and cardiovascular risk factors. At the 6-month follow-up, change in peak walking time (the primary end point) was greatest for SE, intermediate for ST, and least with OMC (mean change versus baseline, 5.8±4.6, 3.7±4.9, and 1.2±2.6 minutes, respectively; P<0.001 for the comparison of SE versus OMC, P=0.02 for ST versus OMC, and P=0.04 for SE versus ST). Although disease-specific quality of life as assessed by the Walking Impairment Questionnaire and Peripheral Artery Questionnaire also improved with both SE and ST compared with OMC, for most scales, the extent of improvement was greater with ST than SE. Free-living step activity increased more with ST than with either SE or OMC alone (114±274 versus 73±139 versus −6±109 steps per hour), but these differences were not statistically significant. Conclusions— SE results in superior treadmill walking performance than ST, even for those with aortoiliac peripheral artery disease. The contrast between better walking performance for SE and better patient-reported quality of life for ST warrants further study. Clinical Trial Registration— URL: http://clinicaltrials.gov/ct/show/NCT00132743?order=1. Unique identifier: NCT00132743.

Mechanisms of restenosis and redilation within coronary stents—Quantitative angiographic assessment

OBJECTIVES This study was designed to assess the relative contributions of intimal hyperplasia and stent compression to the lumen narrowing seen after intracoronary stenting and to determine whether the lumen enlargement produced by angioplasty of in-stent restenosis results primarily from compression or extrusion of intimal hyperplasia through the stent or from additional stent expansion. BACKGROUND Palmaz-Schatz stent placement outwardly displaces plaque and eliminates elastic vessel recoil to provide a large and smooth lumen. Some degree of late lumen narrowing occurs within each stent and causes significant restenosis (> or = 50% stenosis) in 25% to 30% of treated lesions. It has not been clear, however, whether this narrowing results from stent compression (crush) or from in-stent intimal hyperplasia. Because the Palmaz-Schatz stent has a distinct radiographic shadow, it is possible to determine the late diameter of both the stent and the enclosed vessel lumen to assess the relative contributions of these two processes. METHODS From cineangiograms, initial (after stenting) and late (follow-up) lumen and stent diameters were examined in 55 patients (59 stents, group I) who had both immediate and 6-month (192 +/- 117 days) angiography. Lumen and stent diameter were also examined before and after dilation in 30 patients (30 stents, group II) who underwent angioplasty of severe in-stent restenosis. RESULTS Late loss in minimal lumen diameter was 0.99 +/- 0.87 mm for group I despite only a slight (0.03 +/- 0.23-mm) reduction in the corresponding stent diameter. After redilation for in-stent restenosis, the acute gain in minimal lumen diameter was 1.51 +/- 0.82 mm for group II, again without appreciable increase (0.06 +/- 0.20 mm) in stent diameter. CONCLUSIONS Restenosis after intracoronary Palmaz-Schatz stenting appears to be due predominantly to lumen encroachment by intimal hyperplasia within the stent, with minimal contribution of stent compression. Lumen enlargement after coronary angioplasty of in-stent restenosis appears to be due primarily to compression or extrusion of intimal hyperplasia through the stent, or both, rather than to further stent expansion.

In-Hospital and One-Year Economic Outcomes After Coronary Stenting or Balloon Angioplasty Results From a Randomized Clinical Trial

BACKGROUND Coronary stenting has been shown to improve initial success, reduce angiographic restenosis, and reduce the need for repeat revascularization compared with conventional balloon angioplasty (PTCA). Although previous studies have demonstrated that initial hospital costs for stenting are considerably higher than those for conventional PTCA, the impact of coronary stenting on long-term medical care costs remains unknown. METHODS AND RESULTS Between January 1991 and June 1993, 207 consecutive patients with symptomatic coronary disease requiring revascularization of a single coronary lesion were randomized to receive initial treatment by either PTCA (n = 105) or Palmaz-Schatz coronary stent implantation (n = 102) in the multicenter STRESS trial. Detailed resource utilization and cost data were collected for each patients initial hospitalization and for any subsequent hospital visits for 1 year after randomization. Compared with conventional angioplasty, coronary stenting resulted in additional catheterization laboratory costs, increased vascular complications, and longer length of stay. Initial hospital costs were thus approximately

Palmaz-Schatz stenting for treatment of focal vein graft stenosis: Immediate results and long-term outcome

2200 higher for stenting than for PTCA (

Effect of Continuous Quality Improvement Analysis on the Delivery of Primary Percutaneous Transluminal Coronary Angioplasty for Acute Myocardial Infarction

9738 +/- 3248 versus

Diagnostic Yield and Optimal Duration of Continuous-Loop Event Monitoring for the Diagnosis of Palpitations: A Cost-Effectiveness Analysis

7505 +/- 5015; P < .001). Over the first year of follow-up, however, patients assigned to initial stenting were less likely to require rehospitalization for a cardiac condition and underwent fewer subsequent revascularization procedures. Follow-up medical care costs thus tended to be lower for stenting than for conventional angioplasty (

Impact of a practice guideline for patients with atrial fibrillation on medical resource utilization and costs

1918 +/- 4841 versus

Predicting Restenosis of Drug-Eluting Stents Placed in Real-World Clinical Practice Derivation and Validation of a Risk Model From the EVENT Registry

3359 +/- 7100, P = .21). Nonetheless, cumulative 1-year medical care costs remained higher for patients undergoing initial stenting (