Leif Thuesen

Randomized Study on Simple Versus Complex Stenting of Coronary Artery Bifurcation Lesions: The Nordic Bifurcation Study

Background— The optimal stenting strategy in coronary artery bifurcation lesions is unknown. In the present study, a strategy of stenting both the main vessel and the side branch (MV+SB) was compared with a strategy of stenting the main vessel only, with optional stenting of the side branch (MV), with sirolimus-eluting stents. Methods and Results— A total of 413 patients with a bifurcation lesion were randomized. The primary end point was a major adverse cardiac event: cardiac death, myocardial infarction, target-vessel revascularization, or stent thrombosis after 6 months. At 6 months, there were no significant differences in rates of major adverse cardiac events between the groups (MV+SB 3.4%, MV 2.9%; P=NS). In the MV+SB group, there were significantly longer procedure and fluoroscopy times, higher contrast volumes, and higher rates of procedure-related increases in biomarkers of myocardial injury. A total of 307 patients had a quantitative coronary assessment at the index procedure and after 8 months. The combined angiographic end point of diameter stenosis >50% of main vessel and occlusion of the side branch after 8 months was found in 5.3% in the MV group and 5.1% in the MV+SB group (P=NS). Conclusions— Independent of stenting strategy, excellent clinical and angiographic results were obtained with percutaneous treatment of de novo coronary artery bifurcation lesions with sirolimus-eluting stents. The simple stenting strategy used in the MV group was associated with reduced procedure and fluoroscopy times and lower rates of procedure-related biomarker elevation. Therefore, this strategy can be recommended as the routine bifurcation stenting technique.

System delay and mortality among patients with STEMI treated with primary percutaneous coronary intervention

CONTEXT Timely reperfusion therapy is recommended for patients with ST-segment elevation myocardial infarction (STEMI), and door-to-balloon delay has been proposed as a performance measure in triaging patients for primary percutaneous coronary intervention (PCI). However, focusing on the time from first contact with the health care system to the initiation of reperfusion therapy (system delay) may be more relevant, because it constitutes the total time to reperfusion modifiable by the health care system. No previous studies have focused on the association between system delay and outcome in patients with STEMI treated with primary PCI. OBJECTIVE To evaluate the associations between system, treatment, patient, and door-to-balloon delays and mortality in patients with STEMI. DESIGN, SETTING, AND PATIENTS Historical follow-up study based on population-based Danish medical registries of patients with STEMI transported by the emergency medical service and treated with primary PCI from January 1, 2002, to December 31, 2008, at 3 high-volume PCI centers in Western Denmark. Patients (N = 6209) underwent primary PCI within 12 hours of symptom onset. The median follow-up time was 3.4 (interquartile range, 1.8-5.2) years. MAIN OUTCOME MEASURES Crude and adjusted hazard ratios of mortality obtained by Cox proportional regression analysis. RESULTS A system delay of 0 through 60 minutes (n = 347) corresponded to a long-term mortality rate of 15.4% (n = 43); a delay of 61 through 120 minutes (n = 2643) to a rate of 23.3% (n = 380); a delay of 121 through 180 minutes (n = 2092) to a rate of 28.1% (n = 378); and a delay of 181 through 360 minutes (n = 1127) to a rate of 30.8% (n = 275) (P < .001). In multivariable analysis adjusted for other predictors of mortality, system delay was independently associated with mortality (adjusted hazard ratio, 1.10 [95% confidence interval, 1.04-1.16] per 1-hour delay), as was its components, prehospital system delay and door-to-balloon delay. CONCLUSION System delay was associated with mortality in patients with STEMI treated with primary PCI.

Exenatide reduces reperfusion injury in patients with ST-segment elevation myocardial infarction.

AIMS Exenatide, a glucagon-like-peptide-1 analogue, increases myocardial salvage in experimental settings with coronary occlusion and subsequent reperfusion. We evaluated the cardioprotective effect of exenatide at the time of reperfusion in patients with ST-segment elevation myocardial infarction (STEMI) treated with primary percutaneous coronary intervention (pPCI). METHODS AND RESULTS A total of 172 patients with STEMI and Thrombolysis in Myocardial Infarction flow 0/1 were randomly assigned to exenatide or placebo (saline) intravenously. Study treatment was commenced 15 min before intervention and maintained for 6 h after the procedure. The primary endpoint was salvage index calculated from myocardial area at risk (AAR), measured in the acute phase, and final infarct size measured 90 ± 21 days after pPCI by cardiac magnetic resonance (CMR). In 105 patients evaluated with CMR, a significantly larger salvage index was found in the exenatide group than in the placebo group (0.71 ± 0.13 vs. 0.62 ± 0.16; P= 0.003). Infarct size in relation to AAR was also smaller in the exenatide group (0.30 ± 0.15 vs. 0.39 ± 0.15; P= 0.003). In a regression analysis, there was a significant correlation between the infarct size and the AAR for both treatment groups and an analysis of covariance showed that datapoints in the exenatide group lay significantly lower than for the placebo group (P= 0.011). There was a trend towards smaller absolute infarct size in the exenatide group (13 ± 9 vs. 17 ± 14 g; P= 0.11). No difference was observed in left ventricular function or 30-day clinical events. No adverse effects of exenatide were observed. CONCLUSION In patients with STEMI undergoing pPCI, administration of exenatide at the time of reperfusion increases myocardial salvage.

Evaluation of the Second Generation of a Bioresorbable Everolimus Drug-Eluting Vascular Scaffold for Treatment of De Novo Coronary Artery StenosisClinical Perspective

Background— The first generation of the bioresorbable everolimus drug-eluting vascular scaffold showed signs of shrinkage at 6 months, which largely contributed to late luminal loss. Nevertheless, late luminal loss was less than that observed with bare metal stents. To maintain the mechanical integrity of the device up to 6 months, the scaffold design and manufacturing process of its polymer were modified. Methods and Results— Quantitative coronary angiography, intravascular ultrasound with analysis of radiofrequency backscattering, and as an optional assessment, optical coherence tomography (OCT) were performed at baseline and at a 6-month follow-up. Forty-five patients successfully received a single bioresorbable everolimus drug-eluting vascular scaffold. One patient had postprocedural release of myocardial enzyme without Q-wave occurrence; 1 patient with OCT-diagnosed disruption of the scaffold caused by excessive postdilatation was treated 1 month later with a metallic drug-eluting stent. At follow-up, 3 patients declined recatheterization, 42 patients had quantitative coronary angiography, 37 had quantitative intravascular ultrasound, and 25 had OCT. Quantitative coronary angiography disclosed 1 edge restenosis (1 of 42; in-segment binary restenosis, 2.4%). At variance with the ultrasonic changes seen with the first generation of bioresorbable everolimus drug-eluting vascular scaffold at 6 months, the backscattering of the polymeric struts did not decrease over time, the scaffold area was reduced by only 2.0% with intravascular ultrasound, and no change was noted with OCT. On an intention-to-treat basis, the late lumen loss amounted to 0.19±0.18 mm with a limited relative decrease in minimal luminal area of 5.4% on intravascular ultrasound. OCT showed at follow-up that 96.8% of the struts were covered and that malapposition of at least 1 strut, initially observed in 12 scaffolds, was detected at follow-up in only 3 scaffolds. Mean neointimal growth measured by OCT between and on top of the polymeric struts equaled 1.25 mm2, or 16.6% of the scaffold area. Conclusion— Modified manufacturing process of the polymer and geometric changes in the polymeric platform have substantially improved the medium-term performance of this new generation of drug-eluting scaffold to become comparable to those of current drug eluting stents. Clinical Trial Registration— URL: http://clinicaltrials.gov. Unique identifier: NCT00856856.

Percutaneous coronary angioplasty versus coronary artery bypass grafting in treatment of unprotected left main stenosis (NOBLE): a prospective, randomised, open-label, non-inferiority trial

BACKGROUND Coronary artery bypass grafting (CABG) is the standard treatment for revascularisation in patients with left main coronary artery disease, but use of percutaneous coronary intervention (PCI) for this indication is increasing. We aimed to compare PCI and CABG for treatment of left main coronary artery disease. METHODS In this prospective, randomised, open-label, non-inferiority trial, patients with left main coronary artery disease were enrolled in 36 centres in northern Europe and randomised 1:1 to treatment with PCI or CABG. Eligible patients had stable angina pectoris, unstable angina pectoris, or non-ST-elevation myocardial infarction. Exclusion criteria were ST-elevation myocardial infarction within 24 h, being considered too high risk for CABG or PCI, or expected survival of less than 1 year. The primary endpoint was major adverse cardiac or cerebrovascular events (MACCE), a composite of all-cause mortality, non-procedural myocardial infarction, any repeat coronary revascularisation, and stroke. Non-inferiority of PCI to CABG required the lower end of the 95% CI not to exceed a hazard ratio (HR) of 1·35 after up to 5 years of follow-up. The intention-to-treat principle was used in the analysis if not specified otherwise. This trial is registered with ClinicalTrials.gov identifier, number NCT01496651. FINDINGS Between Dec 9, 2008, and Jan 21, 2015, 1201 patients were randomly assigned, 598 to PCI and 603 to CABG, and 592 in each group entered analysis by intention to treat. Kaplan-Meier 5 year estimates of MACCE were 29% for PCI (121 events) and 19% for CABG (81 events), HR 1·48 (95% CI 1·11-1·96), exceeding the limit for non-inferiority, and CABG was significantly better than PCI (p=0·0066). As-treated estimates were 28% versus 19% (1·55, 1·18-2·04, p=0·0015). Comparing PCI with CABG, 5 year estimates were 12% versus 9% (1·07, 0·67-1·72, p=0·77) for all-cause mortality, 7% versus 2% (2·88, 1·40-5·90, p=0·0040) for non-procedural myocardial infarction, 16% versus 10% (1·50, 1·04-2·17, p=0·032) for any revascularisation, and 5% versus 2% (2·25, 0·93-5·48, p=0·073) for stroke. INTERPRETATION The findings of this study suggest that CABG might be better than PCI for treatment of left main stem coronary artery disease. FUNDING Biosensors, Aarhus University Hospital, and participating sites.

Dynamics of vessel wall changes following the implantation of the Absorb everolimus-eluting bioresorbable vascular scaffold: a multi-imaging modality study at 6, 12, 24 and 36 months

AIMS To assess observations with multimodality imaging of the Absorb bioresorbable everolimus-eluting vascular scaffold performed in two consecutive cohorts of patients who were serially investigated either at 6 and 24 months or at 12 and 36 months. METHODS AND RESULTS In the ABSORB multicentre single-arm trial, 45 patients (cohort B1) and 56 patients (cohort B2) underwent serial invasive imaging, specifically quantitative coronary angiography (QCA), intravascular ultrasound (IVUS), radiofrequency backscattering (IVUS-VH) and optical coherence tomography (OCT). Between one and three years, late luminal loss remained unchanged (6 months: 0.19 mm, 1 year: 0.27 mm, 2 years: 0.27 mm, 3 years: 0.29 mm) and the in-segment angiographic restenosis rate for the entire cohort B (n=101) at three years was 6%. On IVUS, mean lumen, scaffold, plaque and vessel area showed enlargement up to two years. Mean lumen and scaffold area remained stable between two and three years whereas significant reduction in plaque behind the struts occurred with a trend toward adaptive restrictive remodelling of EEM. Hyperechogenicity of the vessel wall, a surrogate of the bioresorption process, decreased from 23.1% to 10.4% with a reduction of radiofrequency backscattering for dense calcium and necrotic core. At three years, the count of strut cores detected on OCT increased significantly, probably reflecting the dismantling of the scaffold; 98% of struts were covered. In the entire cohort B (n=101), the three-year major adverse cardiac event rate was 10.0% without any scaffold thrombosis. CONCLUSIONS The current investigation demonstrated the dynamics of vessel wall changes after implantation of a bioresorbable scaffold, resulting at three years in stable luminal dimensions, a low restenosis rate and a low clinical major adverse cardiac events rate. CLINICAL TRIAL REGISTRATION INFORMATION http://www.clinicaltrials.gov/ct2/show/NCT00856856.

Randomized Comparison of Final Kissing Balloon Dilatation Versus No Final Kissing Balloon Dilatation in Patients With Coronary Bifurcation Lesions Treated With Main Vessel Stenting The Nordic-Baltic Bifurcation Study III

Background— It is unknown whether the preferred 1-stent bifurcation stenting approach with stenting of the main vessel (MV) and optional side branch stenting using drug-eluting stents should be finalized by a kissing balloon dilatation (FKBD). Therefore, we compared strategies of MV stenting with and without FKBD. Methods and Results— We randomized 477 patients with a bifurcation lesion to FKBD (n=238) or no FKBD (n=239) after MV stenting. The primary end point was major adverse cardiac events: cardiac death, non–procedure-related index lesion myocardial infarction, target lesion revascularization, or stent thrombosis within 6 months. The 6-month major adverse cardiac event rates were 2.1% and 2.5% (P=1.00) in the FKBD and no-FKBD groups, respectively. Procedure and fluoroscopy times were longer and more contrast media was needed in the FKBD group than in the no-FKBD group. Three hundred twenty-six patients had a quantitative coronary assessment. At 8 months, the rate of binary (re)stenosis in the entire bifurcation lesion (MV and side branch) was 11.0% versus 17.3% (P=0.11), in the MV was 3.1% versus 2.5% (P=0.68), and in the side branch was 7.9% versus 15.4% (P=0.039) in the FKBD versus no-FKBD groups, respectively. In patients with true bifurcation lesions, the side branch restenosis rate was 7.6% versus 20.0% (P=0.024) in the FKBD and no-FKBD groups, respectively. Conclusions— MV stenting strategies with and without FKBD were associated with similar clinical outcomes. FKBD reduced angiographic side branch (re)stenosis, especially in patients with true bifurcation lesions. The simple no-FKBD procedures resulted in reduced use of contrast media and shorter procedure and fluoroscopy times. Long-term data on stent thrombosis are needed. Clinical Trial Registration— URL: http://clinicaltrials.gov. Unique identifier: NCT00914199.

First Serial Assessment at 6 Months and 2 Years of the Second Generation of Absorb Everolimus-Eluting Bioresorbable Vascular Scaffold A Multi-Imaging Modality Study

Background—Nonserial observations have shown this bioresorbable scaffold to have no signs of area reduction at 6 months and recovery of vasomotion at 1 year. Serial observations at 6 months and 2 years have to confirm the absence of late restenosis or unfavorable imaging outcomes. Methods and Results—The ABSORB trial is a multicenter single-arm trial assessing the safety and performance of an everolimus-eluting bioresorbable vascular scaffold. Forty-five patients underwent serial invasive imaging, such as quantitative coronary angiography, intravascular ultrasound, and optical coherence tomography at 6 and 24 months of follow-up. From 6 to 24 months, late luminal loss increased from 0.16±0.18 to 0.27±0.20 mm on quantitative coronary angiography, with an increase in neointima of 0.68±0.43 mm2 on optical coherence tomography and 0.17±0.26 mm2 on intravascular ultrasound. Struts still recognizable on optical coherence tomography at 2 years showed 99% of neointimal coverage with optical and ultrasonic signs of bioresorption accompanied by increase in mean scaffold area compared with baseline (0.54±1.09 mm2 on intravascular ultrasound, P=0.003 and 0.77±1.33 m2 on optical coherence tomography, P=0.016). Two-year major adverse cardiac event rate was 6.8% without any scaffold thrombosis. Conclusions—This serial analysis of the second generation of the everolimus-eluting bioresorbable vascular scaffold confirmed, at medium term, the safety and efficacy of the new device. Clinical Trial Registration—URL: http://www.clinicaltrials.gov. Unique identifier: NCT00856856.

Comparison of Paclitaxel- and Sirolimus-Eluting Stents in Everyday Clinical Practice: The SORT OUT II Randomized Trial

CONTEXT Approval of drug-eluting coronary stents was based on results of relatively small trials of selected patients; however, in routine practice, stents are used in a broader spectrum of patients. OBJECTIVE To compare the first 2 commercially available drug-eluting stents-sirolimus-eluting and paclitaxel-eluting-for prevention of symptom-driven clinical end points, using a study design reflecting everyday clinical practice. DESIGN, SETTING, AND PATIENTS Randomized, blinded trial conducted August 2004 to January 2006 at 5 university hospitals in Denmark. Patients were 2098 men and women (mean [SD] age, 63.6 [10.8] years) treated with percutaneous coronary intervention (PCI) and randomized to receive either sirolimus-eluting (n = 1065) or paclitaxel-eluting (n = 1033) stents. Indications for PCI included ST-segment elevation myocardial infarction (STEMI), non-STEMI or unstable angina pectoris, and stable angina. MAIN OUTCOME MEASURES The primary end point was a composite clinical end point of major adverse cardiac events, defined as either cardiac death, acute myocardial infarction, target lesion revascularization, or target vessel revascularization. Secondary end points included individual components of the composite end point, all-cause mortality, and stent thrombosis. RESULTS The sirolimus- and the paclitaxel-eluting stent groups did not differ significantly in major adverse cardiac events (98 [9.3%] vs 114 [11.2%]; hazard ratio, 0.83 [95% confidence interval, 0.63-1.08]; P = .16) or in any of the secondary end points. The stent thrombosis rates were 27 (2.5%) and 30 (2.9%) (hazard ratio, 0.87 [95% confidence interval, 0.52-1.46]; P = .60), respectively. CONCLUSION In this practical randomized trial, there were no significant differences in clinical outcomes between patients receiving sirolimus- and paclitaxel-eluting stents. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00388934.

Five-year clinical and functional multislice computed tomography angiographic results after coronary implantation of the fully resorbable polymeric everolimus-eluting scaffold in patients with de novo coronary artery disease: the ABSORB cohort A trial

OBJECTIVES This study sought to demonstrate the 5-year clinical and functional multislice computed tomography angiographic results after implantation of the fully resorbable everolimus-eluting scaffold (Absorb BVS, Abbott Vascular, Santa Clara, California). BACKGROUND Multimodality imaging of the first-in-humans trial using a ABSORB BVS scaffold demonstrated at 2 years the bioresorption of the device while preventing restenosis. However, the long-term safety and efficacy of this therapy remain to be documented. METHODS In the ABSORB cohort A trial (ABSORB Clinical Investigation, Cohort A [ABSORB A] Everolimus-Eluting Coronary Stent System Clinical Investigation), 30 patients with a single de novo coronary artery lesion were treated with the fully resorbable everolimus-eluting Absorb scaffold at 4 centers. As an optional investigation in 3 of the 4 centers, the patients underwent multislice computed tomography (MSCT) angiography at 18 months and 5 years. Acquired MSCT data were analyzed at an independent core laboratory (Cardialysis, Rotterdam, the Netherlands) for quantitative analysis of lumen dimensions and was further processed for calculation of fractional flow reserve (FFR) at another independent core laboratory (Heart Flow, Redwood City, California). RESULTS Five-year clinical follow-up is available for 29 patients. One patient withdrew consent after 6 months, but the vital status of this patient remains available. At 46 days, 1 patient experienced a single episode of chest pain and underwent a target lesion revascularization with a slight troponin increase after the procedure. At 5 years, the ischemia-driven major adverse cardiac event rate of 3.4% remained unchanged. Clopidogrel was discontinued in all but 1 patient. Scaffold thrombosis was not observed in any patient. Two noncardiac deaths were reported, 1 caused by duodenal perforation and the other from Hodgkins disease. At 5 years, 18 patients underwent MSCT angiography. All scaffolds were patent, with a median minimal lumen area of 3.25 mm(2) (interquartile range: 2.20 to 4.30). Noninvasive FFR analysis was feasible in 13 of 18 scans, which yielded a median distal FFR of 0.86 (interquartile range: 0.82 to 0.94). CONCLUSIONS The low event rate at 5 years suggests sustained safety after the implantation of a fully bioresorbable Absorb everolimus-eluting scaffold. Noninvasive assessment of the coronary artery with an option of functional assessment could be an alternative to invasive imaging after treatment of coronary narrowing with such a polymeric bioresorbable scaffold. (ABSORB Clinical Investigation, Cohort A [ABSORB A] Everolimus-Eluting Coronary Stent System Clinical Investigation [ABSORB]; NCT00300131).