Visual estimation versus different quantitative coronary angiography methods to assess lesion severity in bifurcation lesions.

OBJECTIVES: To compare visual estimation with different quantitative coronary angiography (QCA) methods (single-vessel versus bifurcation software) to assess coronary bifurcation lesions. BACKGROUND: QCA has been developed to overcome the limitations of visual estimation. Conventional QCA however, developed in "straight vessels," has proved to be inaccurate in bifurcation lesions. Therefore, bifurcation QCA was developed. However, the impact of these different modalities on bifurcation lesion severity classification is yet unknown METHODS: From a randomized controlled trial investigating a novel bifurcation stent (Clinicaltrials.gov NCT01258972), patients with baseline assessment of lesion severity by means of visual estimation, single-vessel QCA, 2D bifurcation QCA and 3D bifurcation QCA were included. We included 113 bifurcations lesions in which all 5 modalities were assessed. The primary end-point was to evaluate how the different modalities affected the classification of bifurcation lesion severity and extent of disease. RESULTS: On visual estimation, 100% of lesions had side-branch diameter stenosis (%DS) >50%, whereas in 83% with single-vessel QCA, 27% with 2D bifurcation QCA and 26% with 3D bifurcation QCA a side-branch %DS >50% was found (P < 0.0001). With regard to the percentage of "true" bifurcation lesions, there was a significant difference between visual estimate (100%), single-vessel QCA (75%) and bifurcation QCA (17% with 2D bifurcation software and 13% with 3D bifurcation software, P < 0.0001). CONCLUSIONS: Our study showed that bifurcation lesion complexity was significantly affected when more advanced bifurcation QCA software were used. "True" bifurcation lesion rate was 100% on visual estimation, but as low as 13% when analyzed with dedicated bifurcation QCA software.

Impact of Coronary Artery Disease Severity Assessed With the SYNTAX Score on Outcomes Following Transcatheter Aortic Valve Replacement.

BACKGROUND: The influence of coronary artery disease (CAD) on clinical and echocardiographic outcomes after transcatheter aortic valve replacement (TAVR) is still controversial. We sought to evaluate the impact of CAD severity as measured by the SYNTAX score (SS) on patients undergoing TAVR. METHODS AND RESULTS: A total of 377 patients who underwent TAVR in 2 high-volume centers in North America were included in our retrospective analysis. A blinded angiographic core laboratory calculated the SS on all available coronary angiograms with the use of quantitative coronary analysis. Patients were stratified into 4 groups: (1) no CAD (SS=0); (2) low SS (SS between 1 and 22); (3) intermediate SS (SS between 23 and 32); and (4) high SS (SS ≥33). Patients who had undergone percutaneous coronary intervention within 6 months prior to TAVR were separated into 2 categories based on their residual SS (<8 and ≥8). Patients with previous coronary artery bypass grafting (CABG) were divided into 2 groups: (1) low CABG SS and (2) high CABG SS. The primary end point was a composite of all-cause mortality, myocardial infarction, and stroke. At 30 days and 1 year, both the presence and the severity of CAD had no impact on the rate of the combined primary end point and on all-cause mortality, cardiovascular mortality, and myocardial infarction. Patients with less complete revascularization (residual SS ≥8 versus residual SS <8 and low CABG SS versus high CABG SS, had similar rates of the combined primary end point, all-cause mortality, cardiovascular mortality, MI, and stroke, at both 30 days and 1 year. CONCLUSIONS: In our core laboratory-validated study, neither the severity of CAD nor completeness of revascularization after percutaneous coronary intervention or CABG were associated with clinical outcomes after TAVR, at both 30 days and 1 year.

Outcomes of a dedicated stent in coronary bifurcations with large side branches: A subanalysis of the randomized TRYTON bifurcation study.

OBJECTIVES: To examine the benefit of the Tryton dedicated side branch (SB) stent compared with provisional stenting in the treatment of complex bifurcation lesions involving large SBs. BACKGROUND: The TRYTON Trial was designed to evaluate the utility of a dedicated SB stent to treat true bifurcation lesions involving large (≥2.5 mm by visual estimation) SBs. Patient enrolled in the trial had smaller SB diameters than intended (59% SB ≤2.25 mm by Core Lab QCA). The TRYTON Trial did not meet its primary endpoint due to an increased rate of peri-procedural myocardial infarctions (MIs). METHODS: The TRYTON Trial randomized 704 patients to the Tryton SB stent with main vessel DES versus provisional SB treatment with main vessel DES. The rates of the primary end point of target vessel failure and the secondary powered end point of angiographic percent diameter stenosis in the SB at 9 months were assessed and compared between the two treatment strategies among patients with a SB ≥2.25 mm diameter at baseline determined by Core Lab QCA. RESULTS: Among the 704 patients enrolled in the TRYTON Trial, 289 patients (143 provisional and 146 Tryton stent; 41% of entire cohort) had a SB ≥2.25 mm. The primary end point of TVF was numerically lower in the Tryton group compared with the provisional group (11.3% vs. 15.6%, P = 0.38), and was within the non-inferiority margin. No difference among the rates of clinically driven target vessel revascularization (3.5% vs. 4.3% P = 0.77) or cardiac death (0% both groups) were seen. In-segment percent diameter stenosis of the SB was significantly lower in the Tryton group compared with the provisional group (30.4% vs. 40.6%, P = 0.004). CONCLUSIONS: Analysis of the TRYTON Trial cohort of SB ≥2.25 mm supports the safety and efficacy of the Tryton SB stent compared with a provisional stenting strategy in the treatment of bifurcation lesions involving large SBs. © 2015 Wiley Periodicals, Inc.

Impact of intracoronary injection of CD133+ bone marrow stem cells on coronary atherosclerotic progression in patients with STEMI: a COMPARE-AMI IVUS substudy.

OBJECTIVES: Adverse effects of intracoronary injection of stem cells on in-stent restenosis and atherosclerotic progression remain unclear. We sought to evaluate the adverse effects of intracoronary injection of CD133 cells on in-stent restenosis and atherosclerotic progression in the infarct-related and contralateral arteries using serial intravascular ultrasound (IVUS) analysis. METHODS: Baseline and 4-month follow-up IVUS images were obtained from 17 patients treated with intracoronary stem cell injection and 20 placebo patients after primary percutaneous coronary intervention in the COMPARE-AMI trial. In the infarct-related artery, the stented segment, 5 mm proximal and distal reference segments, and proximal and distal nonstented segments were analyzed every 1 mm; the entire segment of a contralateral artery was also analyzed every 1 mm. RESULTS: In the infarct-related artery analysis, the median percentage of in-stent neointimal hyperplasia (12.1 vs. 7.6%, P=0.95), the reduction in the minimum lumen area (MLA; -1.6 vs. -1.5 mm(2), P=0.97), and the MLA at follow-up (4.3 vs. 5.3 mm(2), P=0.21) were found to be similar between the stem cell and placebo groups. Changes in proximal and distal nonstented segment lumen areas and plaque burden were also similar between the stem cell and placebo groups; however, there was a decrease in the maximum arc of the attenuated plaque behind the stent from baseline to follow-up in the placebo group (P=0.004), but not in the stem cell group. In the contralateral artery, there were no differences in changes in MLA, plaque burden, or attenuated plaque between stem cell and placebo patients. CONCLUSION: Intracoronary injection of CD133(+) bone marrow stem cells has no IVUS-detectable effect on neointimal hyperplasia or atherosclerosis progression in either infarct-related or contralateral arteries.

Inter-core lab variability in analyzing quantitative coronary angiography for bifurcation lesions: a post-hoc analysis of a randomized trial.

OBJECTIVES: This study sought to evaluate inter-core lab variability in quantitative coronary angiography (QCA) analysis of bifurcation lesions. BACKGROUND: QCA of bifurcation lesions is challenging. To date there are no data available on the inter-core lab variability of bifurcation QCA analysis. METHODS: The randomized Tryton IDE (Tryton Pivotal IDE Coronary Bifurcation Trial) compared the Tryton Side Branch Stent (Tryton Medical, Durham, North Carolina) with balloon angioplasty as side branch treatment. QCA was performed in an angiographic subcohort (n = 326) at 9-month follow-up. Inter-core lab variability of QCA analysis between the Cardiovascular Research Foundation and the Cardialysis core labs was evaluated before and after alignment of the used QCA methodology using angiographic data derived from this angiographic follow-up cohort. RESULTS: In the original analysis, before alignment of QCA methodology, the mean difference between the core labs (bias) was large for all QCA parameters with wide 95% limits of agreement (1.96 × SD of the bias), indicating marked variability. The bias of the key angiographic endpoint of the Tryton trial, in-segment percentage diameter stenosis (%DS) of the side branch, was 5.5% (95% limits of agreement: -26.7% to 37.8%). After reanalysis, the bias of the in-segment %DS of the side branch reduced to 1.8% (95% limits of agreement: -16.7% to 20.4%). Importantly, after alignment of the 2 core labs, there was no longer a difference between both treatment groups (%DS of the side branch: treatment group A vs. group B: 34.4 ± 19.4% vs. 32.4 ± 16.1%, p = 0.340). CONCLUSIONS: Originally, a marked inter-core lab variability of bifurcation QCA analysis was found. After alignment of methodology, inter-core lab variability decreased considerably and impacted angiographic trial results. This latter finding emphasizes the importance of using the same methodology among different core labs worldwide. (Tryton Pivotal Prospective, Single Blind, Randomized Controlled Study to Evaluate the Safety & Effectiveness of the Tryton Side Branch Stent Used With DES in Treatment of de Novo Bifurcation Lesions in the Main Branch & Side Branch in Native Coronaries [TRYTON]; NCT01258972).

A randomized trial of a dedicated bifurcation stent versus provisional stenting in the treatment of coronary bifurcation lesions.

BACKGROUND: Bifurcation lesions are frequent among patients with symptomatic coronary disease treated by percutaneous coronary intervention. Current evidence recommends a conservative (provisional) approach when treating the side branch (SB). OBJECTIVES: The TRYTON (Prospective, Single Blind, Randomized Controlled Study to Evaluate the Safety & Effectiveness of the Tryton Side Branch Stent Used With DES in Treatment of de Novo Bifurcation Lesions in the Main Branch & Side Branch in Native Coronaries) bifurcation trial sought to compare treatment of de novo true bifurcation lesions using a dedicated bifurcation stent or SB balloon angioplasty. METHODS: We randomly assigned patients with true bifurcation lesions to a main vessel stent plus provisional stenting or the bifurcation stent. The primary endpoint (powered for noninferiority) was target vessel failure (TVF) (cardiac death, target vessel myocardial infarction, and target vessel revascularization). The secondary angiographic endpoint (powered for superiority) was in-segment percent diameter stenosis of the SB at 9 months. RESULTS: We randomized 704 patients with bifurcation coronary lesions at 58 centers (30 from Europe and 28 from the United States). At 9 months, TVF was 17.4% in the bifurcation stent group compared with 12.8% in the provisional group (p=0.11), mainly because of a higher periprocedural myocardial infarction rate (13.6% vs. 10.1%, p=0.19). The TVF difference of +4.6% (2-sided 95% confidence interval: -1.0 to 10.3; upper limit of the 1-sided 95% confidence interval: 10.3) was not within the pre-specified noninferiority margin of 5.5% (p=0.42 for noninferiority). The SB in-segment diameter stenosis among the angiographic cohort was lower in the bifurcation stent group compared with the provisional group (31.6% vs. 38.6%, p=0.002 for superiority), with no difference in binary restenosis rates (diameter stenosis≥50%) at 9 months follow-up (22.6% vs. 26.8%, p=0.44). CONCLUSIONS: Provisional stenting should remain the preferred strategy for treatment of non-left main true coronary bifurcation lesions. (Prospective, Single Blind, Randomized Controlled Study to Evaluate the Safety & Effectiveness of the Tryton Side Branch Stent Used With DES in Treatment of de Novo Bifurcation Lesions in the Main Branch & Side Branch in Native Coronaries [TRYTON]; NCT01258972).

A randomized trial of deferred stenting versus immediate stenting to prevent no- or slow-reflow in acute ST-segment elevation myocardial infarction (DEFER-STEMI).

OBJECTIVES: The aim of this study was to assess whether deferred stenting might reduce no-reflow and salvage myocardium in primary percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI). BACKGROUND: No-reflow is associated with adverse outcomes in STEMI. METHODS: This was a prospective, single-center, randomized, controlled, proof-of-concept trial in reperfused STEMI patients with ≥1 risk factors for no-reflow. Randomization was to deferred stenting with an intention-to-stent 4 to 16 h later or conventional treatment with immediate stenting. The primary outcome was the incidence of no-/slow-reflow (Thrombolysis In Myocardial Infarction ≤2). Cardiac magnetic resonance imaging was performed 2 days and 6 months after myocardial infarction. Myocardial salvage was the final infarct size indexed to the initial area at risk. RESULTS: Of 411 STEMI patients (March 11, 2012 to November 21, 2012), 101 patients (mean age, 60 years; 69% male) were randomized (52 to the deferred stenting group, 49 to the immediate stenting). The median (interquartile range [IQR]) time to the second procedure in the deferred stenting group was 9 h (IQR: 6 to 12 h). Fewer patients in the deferred stenting group had no-/slow-reflow (14 [29%] vs. 3 [6%]; p = 0.006), no reflow (7 [14%] vs. 1 [2%]; p = 0.052) and intraprocedural thrombotic events (16 [33%] vs. 5 [10%]; p = 0.010). Thrombolysis In Myocardial Infarction coronary flow grades at the end of PCI were higher in the deferred stenting group (p = 0.018). Recurrent STEMI occurred in 2 patients in the deferred stenting group before the second procedure. Myocardial salvage index at 6 months was greater in the deferred stenting group (68 [IQR: 54% to 82%] vs. 56 [IQR: 31% to 72%]; p = 0.031]. CONCLUSIONS: In high-risk STEMI patients, deferred stenting in primary PCI reduced no-reflow and increased myocardial salvage. (Deferred Stent Trial in STEMI; NCT01717573).

Ischemic outcomes after coronary intervention of calcified vessels in acute coronary syndromes. Pooled analysis from the HORIZONS-AMI (Harmonizing Outcomes With Revascularization and Stents in Acute Myocardial Infarction) and ACUITY (Acute Catheterization and Urgent Intervention Triage Strategy) TRIALS.

OBJECTIVES: This study sought to determine the frequency and impact of coronary calcification among patients undergoing percutaneous coronary intervention (PCI) for acute coronary syndromes (ACS). BACKGROUND: Small studies in patients with stable coronary artery disease have suggested a worse prognosis after PCI of calcified compared with noncalcified lesions. Little is known about the impact of coronary calcification on outcomes after PCI for patients presenting with non-ST-segment elevation and ST-segment elevation ACS. METHODS: Data from 6,855 patients presenting with ACS in whom PCI was performed were pooled from 2 large-scale randomized, controlled trials, ACUITY (Acute Catheterization and Urgent Intervention Triage Strategy) and HORIZONS-AMI (Harmonizing Outcomes With Revascularization and Stents in Acute Myocardial Infarction). One-year outcomes were analyzed according to the severity of PCI target lesion calcification (none/mild, moderate, or severe) as assessed by an independent angiographic core laboratory. RESULTS: Target lesion calcification was severe in 402 patients (5.9%), moderate in 1,788 (26.1%), and none/mild in 4,665 (68.1%). Moderate/severe target lesion calcification was more frequent in older patients, men, hypertensive patients, and those presenting with ST-segment elevation myocardial infarction (STEMI). The unadjusted 1-year rates of death, cardiac death, definite stent thrombosis, and ischemic target lesion revascularization (TLR) and target vessel revascularization were significantly increased in patients with moderate/severe target lesion calcification. By multivariable analysis, the presence of moderate/severe target lesion calcification was an independent predictor of 1-year definite stent thrombosis (hazard ratio [HR]: 1.62; 95% confidence interval [CI]: 1.14 to 2.30; p = 0.007) and ischemic TLR (HR: 1.44; 95% CI: 1.17 to 1.78; p = 0.0007). CONCLUSIONS: Moderate/severe lesion calcification was relatively frequent in patients with non-ST-segment elevation ACS and STEMI and was strongly predictive of stent thrombosis and ischemic TLR at 1 year. (Comparison of Angiomax Versus Heparin in Acute Coronary Syndromes [ACS]; NCT00093158; Harmonizing Outcomes With Revascularization and Stents in Acute Myocardial Infarction; NCT00433966).

Impact of intraprocedural stent thrombosis during percutaneous coronary intervention: insights from the CHAMPION PHOENIX Trial (Clinical Trial Comparing Cangrelor to Clopidogrel Standard of Care Therapy in Subjects Who Require Percutaneous Coronary Intervention).

OBJECTIVES: This study sought to evaluate the clinical impact of intraprocedural stent thrombosis (IPST), a relatively new endpoint. BACKGROUND: In the prospective, double-blind, active-controlled CHAMPION PHOENIX (Clinical Trial Comparing Cangrelor to Clopidogrel Standard of Care Therapy in Subjects Who Require Percutaneous Coronary Intervention) trial, cangrelor significantly reduced periprocedural and 30-day ischemic events in patients undergoing percutaneous coronary intervention (PCI), including IPST. METHODS: An independent core laboratory blinded to treatment assignment performed a frame-by-frame angiographic analysis in 10,939 patients for the development of IPST, defined as new or worsening thrombus related to stent deployment at any time during the procedure. Adverse events were adjudicated by an independent, blinded clinical events committee. RESULTS: IPST developed in 89 patients (0.8%), including 35 of 5,470 (0.6%) and 54 of 5,469 (1.0%) patients in the cangrelor and clopidogrel arms, respectively (odds ratio: 0.65; 95% confidence interval: 0.42 to 0.99; p = 0.04). Compared to patients without IPST, IPST was associated with a marked increase in composite ischemia (death, myocardial infarction [MI], ischemia-driven revascularization, or new-onset out-of-laboratory stent thrombosis [Academic Research Consortium]) at 48 h and at 30 days (29.2% vs. 4.5% and 31.5% vs. 5.7%, respectively; p < 0.0001 for both). After controlling for potential confounders, IPST remained a strong predictor of all adverse ischemic events at both time points. CONCLUSIONS: In the large-scale CHAMPION PHOENIX trial, the occurrence of IPST was strongly predictive of subsequent adverse cardiovascular events. The potent intravenous adenosine diphosphate antagonist cangrelor substantially reduced IPST, contributing to its beneficial effects at 48 h and 30 days. (Clinical Trial Comparing Cangrelor to Clopidogrel Standard of Care Therapy in Subjects Who Require Percutaneous Coronary Intervention [PCI] [CHAMPION PHOENIX]; NCT01156571).