Artificial intelligence coronary computed tomography, coronary computed tomography angiography using fractional flow reserve, and physician visual interpretation in the per-vessel prediction of abnormal invasive adenosine fractional flow reserve.

Aims: A comparison of diagnostic performance comparing AI-QCTISCHEMIA, coronary computed tomography angiography using fractional flow reserve (CT-FFR), and physician visual interpretation on the prediction of invasive adenosine FFR have not been evaluated. Furthermore, the coronary plaque characteristics impacting these tests have not been assessed. Methods and results: In a single centre, 43-month retrospective review of 442 patients referred for coronary computed tomography angiography and CT-FFR, 44 patients with CT-FFR had 54 vessels assessed using intracoronary adenosine FFR within 60 days. A comparison of the diagnostic performance among these three techniques for the prediction of FFR ≤ 0.80 was reported. The mean age of the study population was 65 years, 76.9% were male, and the median coronary artery calcium was 654. When analysing the per-vessel ischaemia prediction, AI-QCTISCHEMIA had greater specificity, positive predictive value (PPV), diagnostic accuracy, and area under the curve (AUC) vs. CT-FFR and physician visual interpretation CAD-RADS. The AUC for AI-QCTISCHEMIA was 0.91 vs. 0.76 for CT-FFR and 0.62 for CAD-RADS ≥ 3. Plaque characteristics that were different in false positive vs. true positive cases for AI-QCTISCHEMIA were max stenosis diameter % (54% vs. 67%, P < 0.01); for CT-FFR were maximum stenosis diameter % (40% vs. 65%, P < 0.001), total non-calcified plaque (9% vs. 13%, P < 0.01); and for physician visual interpretation CAD-RADS ≥ 3 were total non-calcified plaque (8% vs. 12%, P < 0.01), lumen volume (681 vs. 510 mm3, P = 0.02), maximum stenosis diameter % (40% vs. 62%, P < 0.001), total plaque (19% vs. 33%, P = 0.002), and total calcified plaque (11% vs. 22%, P = 0.003). Conclusion: Regarding per-vessel prediction of FFR ≤ 0.8, AI-QCTISCHEMIA revealed greater specificity, PPV, accuracy, and AUC vs. CT-FFR and physician visual interpretation CAD-RADS ≥ 3.

3-Year Outcomes After Transcatheter or Surgical Aortic Valve Replacement in Low-Risk Patients With Aortic Stenosis.

BACKGROUND: Randomized data comparing outcomes of transcatheter aortic valve replacement (TAVR) with surgery in low-surgical risk patients at time points beyond 2 years is limited. This presents an unknown for physicians striving to educate patients as part of a shared decision-making process. OBJECTIVES: The authors evaluated 3-year clinical and echocardiographic outcomes from the Evolut Low Risk trial. METHODS: Low-risk patients were randomized to TAVR with a self-expanding, supra-annular valve or surgery. The primary endpoint of all-cause mortality or disabling stroke and several secondary endpoints were assessed at 3 years. RESULTS: There were 1,414 attempted implantations (730 TAVR; 684 surgery). Patients had a mean age of 74 years and 35% were women. At 3 years, the primary endpoint occurred in 7.4% of TAVR patients and 10.4% of surgery patients (HR: 0.70; 95% CI: 0.49-1.00; P = 0.051). The difference between treatment arms for all-cause mortality or disabling stroke remained broadly consistent over time: -1.8% at year 1; -2.0% at year 2; and -2.9% at year 3. The incidence of mild paravalvular regurgitation (20.3% TAVR vs 2.5% surgery) and pacemaker placement (23.2% TAVR vs 9.1% surgery; P < 0.001) were lower in the surgery group. Rates of moderate or greater paravalvular regurgitation for both groups were <1% and not significantly different. Patients who underwent TAVR had significantly improved valve hemodynamics (mean gradient 9.1 mm Hg TAVR vs 12.1 mm Hg surgery; P < 0.001) at 3 years. CONCLUSIONS: Within the Evolut Low Risk study, TAVR at 3 years showed durable benefits compared with surgery with respect to all-cause mortality or disabling stroke. (Medtronic Evolut Transcatheter Aortic Valve Replacement in Low Risk Patients; NCT02701283).

2-Year Outcomes After Transcatheter Versus Surgical Aortic Valve Replacement in Low-Risk Patients.

BACKGROUND: The Evolut Low Risk Trial (Medtronic Evolut Transcatheter Aortic Valve Replacement in Low Risk Patients) showed that transcatheter aortic valve replacement (TAVR) with a supra-annular, self-expanding valve was noninferior to surgery for the primary endpoint of all-cause mortality or disabling stroke at 2 years. This finding was based on a Bayesian analysis performed after 850 patients had reached 1 year of follow-up. OBJECTIVES: The goal of this study was to report the full 2-year clinical and echocardiographic outcomes for patients enrolled in the Evolut Low Risk Trial. METHODS: A total of 1,414 low-surgical risk patients with severe aortic stenosis were randomized to receive TAVR or surgical AVR. An independent clinical events committee adjudicated adverse events, and a central echocardiographic core laboratory assessed hemodynamic endpoints. RESULTS: An attempted implant was performed in 730 TAVR and 684 surgical patients from March 2016 to May 2019. The Kaplan-Meier rates for the complete 2-year primary endpoint of death or disabling stroke were 4.3% in the TAVR group and 6.3% in the surgery group (P = 0.084). These rates were comparable to the interim Bayesian rates of 5.3% with TAVR and 6.7% with surgery (difference: -1.4%; 95% Bayesian credible interval: -4.9% to 2.1%). All-cause mortality rates were 3.5% vs 4.4% (P = 0.366), and disabling stroke rates were 1.5% vs 2.7% (P = 0.119), respectively. Between years 1 and 2, there was no convergence of the primary outcome curves. CONCLUSIONS: The complete 2-year follow-up from the Evolut Low Risk Trial found that TAVR is noninferior to surgery for the primary endpoint of all-cause mortality or disabling stroke, with event rates that were slightly better than those predicted by using the Bayesian analysis. (Medtronic Evolut Transcatheter Aortic Valve Replacement in Low Risk Patients [Evolut Low Risk Trial]; NCT02701283).

Clinical Outcomes Before and After Complete Everolimus-Eluting Bioresorbable Scaffold Resorption: Five-Year Follow-Up From the ABSORB III Trial.

BACKGROUND: The Absorb everolimus-eluting bioresorbable vascular scaffold (BVS) provides early drug delivery and mechanical support similar to those of metallic drug-eluting stents, followed by complete resorption in ≈3 years with recovery of vascular structure and function. The ABSORB III trial demonstrated noninferior rates of target lesion failure (cardiac death, target vessel myocardial infarction, or ischemia-driven target lesion revascularization) at 1 year with BVS compared with cobalt chromium everolimus-eluting stents. Between 1 and 3 years and cumulative to 3 years, adverse event rates (particularly target vessel myocardial infarction and scaffold thrombosis) were increased after BVS. We sought to assess clinical outcomes after BVS through 5 years, including beyond the 3-year time point of complete scaffold resorption. METHODS: Clinical outcomes from ABSORB III were analyzed by randomized device (intention to treat) cumulative to 5 years and between 3 and 5 years. RESULTS: Rates of target lesion failure, target vessel myocardial infarction, and scaffold thrombosis were increased through the 5-year follow-up with BVS compared with everolimus-eluting stents. However, between 3 and 5 years, reductions in the relative hazards of the BVS compared with everolimus-eluting stents were observed, particularly for target lesion failure (hazard ratio, 0.83 [95% CI, 0.55-1.24] versus 1.35 [95% CI, 1.02-1.78]; Pint=0.052) and scaffold thrombosis (hazard ratio, 0.26 [95% CI, 0.02-2.87] versus 3.23 [95% CI, 1.25-8.30]; Pint=0.056) compared with the 0- to 3-year time period. CONCLUSIONS: In the ABSORB III trial, cumulative 5-year adverse event rates were increased after BVS compared with everolimus-eluting stents. However, the period of excess risk for BVS ended at 3 years, coincident with complete scaffold resorption. CLINICAL TRIAL REGISTRATION: URL: https://clinicaltrials.gov. Unique identifier: NCT01751906.

North American Expert Review of Rotational Atherectomy.

Rotational atherectomy (RA) is an established tool in interventional cardiology for treatment of calcified coronary lesions. Over 3 decades of clinical experience and research, techniques have matured and outcomes have improved. Heterogeneity exists, however, in RA utilization and technique. We assembled a group of experienced RA operators and device experts to summarize and critique key elements of contemporary RA technique, to identify areas of consensus and controversy, and to offer recommendations for optimal performance for the practicing interventional cardiologist. Evolution in RA strategy toward a focus on lesion modification to facilitate balloon angioplasty and stenting has underpinned major advances in procedural safety, including opportunity to use smaller caliber equipment and radial access. Optimal technique and improved safety have permitted exploratory use of RA for different lesion types and reevaluation of procedural requirements, including flush solution composition and transvenous pacing. Preparedness to manage complications remains paramount and recommendations for operators and institutions are outlined.

Transcatheter Aortic-Valve Replacement with a Self-Expanding Valve in Low-Risk Patients.

BACKGROUND: Transcatheter aortic-valve replacement (TAVR) is an alternative to surgery in patients with severe aortic stenosis who are at increased risk for death from surgery; less is known about TAVR in low-risk patients. METHODS: We performed a randomized noninferiority trial in which TAVR with a self-expanding supraannular bioprosthesis was compared with surgical aortic-valve replacement in patients who had severe aortic stenosis and were at low surgical risk. When 850 patients had reached 12-month follow-up, we analyzed data regarding the primary end point, a composite of death or disabling stroke at 24 months, using Bayesian methods. RESULTS: Of the 1468 patients who underwent randomization, an attempted TAVR or surgical procedure was performed in 1403. The patients' mean age was 74 years. The 24-month estimated incidence of the primary end point was 5.3% in the TAVR group and 6.7% in the surgery group (difference, -1.4 percentage points; 95% Bayesian credible interval for difference, -4.9 to 2.1; posterior probability of noninferiority >0.999). At 30 days, patients who had undergone TAVR, as compared with surgery, had a lower incidence of disabling stroke (0.5% vs. 1.7%), bleeding complications (2.4% vs. 7.5%), acute kidney injury (0.9% vs. 2.8%), and atrial fibrillation (7.7% vs. 35.4%) and a higher incidence of moderate or severe aortic regurgitation (3.5% vs. 0.5%) and pacemaker implantation (17.4% vs. 6.1%). At 12 months, patients in the TAVR group had lower aortic-valve gradients than those in the surgery group (8.6 mm Hg vs. 11.2 mm Hg) and larger effective orifice areas (2.3 cm2 vs. 2.0 cm2). CONCLUSIONS: In patients with severe aortic stenosis who were at low surgical risk, TAVR with a self-expanding supraannular bioprosthesis was noninferior to surgery with respect to the composite end point of death or disabling stroke at 24 months. (Funded by Medtronic; ClinicalTrials.gov number, NCT02701283.).

Long-Term Safety and Efficacy of Platinum Chromium Everolimus-Eluting Stents in Coronary Artery Disease: 5-Year Results From the PLATINUM Trial.

OBJECTIVES: The authors sought to evaluate the final 5-year safety and effectiveness of the platinum-chromium everolimus-eluting stent (PtCr-EES) in the randomized trial, as well as in 2 single-arm substudies that evaluated PtCr-EES in small vessels (diameter <2.5 mm; n = 94) and long lesions (24 to 34 mm; n = 102). BACKGROUND: In the multicenter, randomized PLATINUM (PLATINUM Clinical Trial to Assess the PROMUS Element Stent System for Treatment of De Novo Coronary Artery Lesions), the PtCr-EES was noninferior to the cobalt-chromium everolimus-eluting stent (CoCr-EES) at 1 year in 1,530 patients undergoing percutaneous coronary intervention. METHODS: Patients with 1 or 2 de novo coronary artery lesions (reference vessel diameter 2.50 to 4.25 mm, length ≤24 mm) were randomized 1:1 to PtCr-EES versus CoCr-EES. All patients in the substudies received PtCr-EES. The primary endpoint was target lesion failure (TLF), a composite of target vessel-related cardiac death, target vessel-related myocardial infarction, or ischemia-driven target lesion revascularization. RESULTS: In the randomized trial, the 5-year TLF rate was 9.1% for PtCr-EES and 9.3% for CoCr-EES (hazard ratio [HR]: 0.97; p = 0.87). Landmark analysis demonstrated similar TLF rates from discharge to 1 year (HR: 1.12; p = 0.70) and from 1 to 5 years (HR: 0.90; p = 0.63). There were no significant differences in the rates of cardiac death, myocardial infarction, target lesion or vessel revascularization, or stent thrombosis. PtCr-EES had 5-year TLF rates of 7.0% in small vessels and 13.6% in long lesions. CONCLUSIONS: PtCr-EES demonstrated comparable safety and effectiveness to CoCr-EES through 5 years of follow-up, with low rates of stent thrombosis and other adverse events. The 5-year event rates were also acceptable in patients with small vessels and long lesions treated with PtCr-EES. (The PLATINUM Clinical Trial to Assess the PROMUS Element Stent System for Treatment of De Novo Coronary Artery Lesions [PLATINUM]; NCT00823212; The PLATINUM Clinical Trial to Assess the PROMUS Element Stent System for Treatment of De Novo Coronary Artery Lesions in Small Vessels [PLATINUM SV]; NCT01498692; The PLATINUM Clinical Trial to Assess the PROMUS Element Stent System for Treatment of Long De Novo Coronary Artery Lesions [PLATINUM LL]; NCT01500434).

3-Year Clinical Outcomes With Everolimus-Eluting Bioresorbable Coronary Scaffolds: The ABSORB III Trial.

BACKGROUND: The Absorb everolimus-eluting poly-L-lactic acid-based bioresorbable vascular scaffold (BVS) provides early drug delivery and mechanical support functions similar to metallic drug-eluting stents (DES), followed by complete bioresorption in approximately 3 years with recovery of vascular structure and function. The ABSORB III trial demonstrated noninferior rates of target lesion failure (cardiac death, target vessel myocardial infarction [TVMI], or ischemia-driven target lesion revascularization) at 1 year in 2,008 patients with coronary artery disease randomized to BVS versus cobalt-chromium everolimus-eluting stents (EES). OBJECTIVES: This study sought to assess clinical outcomes through 3 years following BVS implantation. METHODS: Clinical outcomes from the ABSORB III trial were analyzed by randomized treatment assignment cumulative through 3 years, and between 1 and 3 years. RESULTS: The primary composite endpoint of target lesion failure through 3 years occurred in 13.4% of BVS patients and 10.4% of EES patients (p = 0.06), and between 1 and 3 years in 7.0% versus 6.0% of patients, respectively (p = 0.39). TVMI through 3 years was increased with BVS (8.6% vs. 5.9%; p = 0.03), as was device thrombosis (2.3% vs. 0.7%; p = 0.01). In BVS-assigned patients, treatment of very small vessels (those with quantitatively determined reference vessel diameter <2.25 mm) was an independent predictor of 3-year TLF and scaffold thrombosis. CONCLUSIONS: In the ABSORB III trial, 3-year adverse event rates were higher with BVS than EES, particularly TVMI and device thrombosis. Longer-term clinical follow-up is required to determine whether bioresorption of the polymeric scaffold will influence patient prognosis. (ABSORB III Randomized Controlled Trial [RCT] [ABSORB-III]; NCT01751906).

Influence of smoking on the antiplatelet effect of clopidogrel differs according to clopidogrel dose: Insights from the GRAVITAS trial.

OBJECTIVE: To examine the influence of smoking on the antiplatelet effect of clopidogrel following percutaneous coronary intervention (PCI). BACKGROUND: Certain studies suggest smokers may have enhanced clopidogrel-induced platelet inhibition compared to non-smokers after PCI. Whether this is affected by clopidogrel dose is unknown. METHODS: In this study, we conducted an analysis of 5,429 patients in the Gauging Responsiveness With A VerifyNow P2Y12 Assay: Impact on Thrombosis and Safety (GRAVITAS) trial. Platelet reactivity was assessed 12-24 hr after PCI (baseline). Patients with high on-treatment platelet reactivity (OTR) (P2Y12 reaction units [PRU] ≥ 230) were randomized to clopidogrel 75 mg or 150 mg daily. Reactivity was subsequently assessed at 30-days, and 6-months. Patients were stratified by smoking status. RESULTS: Smoking was independently associated with lower PRU (P = 0.001), and smokers were less likely to have high OTR (odds ratio 0.80, 95% confidence interval 0.68-0.94; P = 0.006) at baseline. Among patients assigned to clopidogrel 75 mg, smokers had lower PRU and were less likely to still have high OTR at 30-days (P < 0.001) and 6-months (P < 0.001). However, in patients assigned clopidogrel 150 mg, PRU and high OTR did not differ by smoking status at any time. Tests demonstrated an interaction between smoking and dose at 30 days (P = 0.007), and a trend at 6-months (P = 0.098). CONCLUSIONS: Smokers treated with clopidogrel exhibit reduced platelet reactivity and are less likely to have persistent high OTR than non-smokers. This difference is mitigated by clopidogrel 150 mg, indicating non-smokers may require double-dose therapy to achieve a similar antiplatelet effect after PCI. © 2016 Wiley Periodicals, Inc.

One-year results of the ICON (Ionic versus non-ionic Contrast to Obviate worsening Nephropathy after angioplasty in chronic renal failure patients) Study.

BACKGROUND: Long-term clinical outcomes after exposure to non-ionic iso-osmolar contrast medium (IOCM) or ionic low-osmolar CM (LOCM) in patients with chronic kidney disease (CKD) undergoing coronary angiography are unclear. METHODS: The ICON trial was a prospective, double-blinded, multicentre study that randomly assigned 146 patients with CKD undergoing coronary angiography with or without percutaneous coronary intervention to the non-ionic IOCM Iodixanol or the ionic LOCM Ioxaglate. We report the 1-year clinical outcomes. RESULTS: After randomization, baseline and procedural characteristics were well-matched between the two groups. At 1 year, three deaths (4.1%) occurred in the ioxaglate and nine deaths in the iodixanol group (13.6%, P = 0.07). The cardiac death rate at 1 year was 2.7% in the ioxaglate group and 9.1% in the iodixanol group (P = 0.07). There were no significant differences in the rates of myocardial infarction (1.4% vs. 1.5%; P = 1.00) and repeated revascularization (6.8% vs. 9.1%; P = 0.75). CONCLUSIONS: The use of ionic LOCM ioxaglate was associated with a numerically lower mortality at 1 year as compared to iodixanol in patients who underwent cardiac catheterization. Future studies evaluating long-term safety following exposure to different types of CM are warranted.

Everolimus-Eluting Bioresorbable Scaffolds for Coronary Artery Disease.

BACKGROUND: In patients with coronary artery disease who receive metallic drug-eluting coronary stents, adverse events such as late target-lesion failure may be related in part to the persistent presence of the metallic stent frame in the coronary-vessel wall. Bioresorbable vascular scaffolds have been developed to attempt to improve long-term outcomes. METHODS: In this large, multicenter, randomized trial, 2008 patients with stable or unstable angina were randomly assigned in a 2:1 ratio to receive an everolimus-eluting bioresorbable vascular (Absorb) scaffold (1322 patients) or an everolimus-eluting cobalt-chromium (Xience) stent (686 patients). The primary end point, which was tested for both noninferiority (margin, 4.5 percentage points for the risk difference) and superiority, was target-lesion failure (cardiac death, target-vessel myocardial infarction, or ischemia-driven target-lesion revascularization) at 1 year. RESULTS: Target-lesion failure at 1 year occurred in 7.8% of patients in the Absorb group and in 6.1% of patients in the Xience group (difference, 1.7 percentage points; 95% confidence interval, -0.5 to 3.9; P=0.007 for noninferiority and P=0.16 for superiority). There was no significant difference between the Absorb group and the Xience group in rates of cardiac death (0.6% and 0.1%, respectively; P=0.29), target-vessel myocardial infarction (6.0% and 4.6%, respectively; P=0.18), or ischemia-driven target-lesion revascularization (3.0% and 2.5%, respectively; P=0.50). Device thrombosis within 1 year occurred in 1.5% of patients in the Absorb group and in 0.7% of patients in the Xience group (P=0.13). CONCLUSIONS: In this large-scale, randomized trial, treatment of noncomplex obstructive coronary artery disease with an everolimus-eluting bioresorbable vascular scaffold, as compared with an everolimus-eluting cobalt-chromium stent, was within the prespecified margin for noninferiority with respect to target-lesion failure at 1 year. (Funded by Abbott Vascular; ABSORB III ClinicalTrials.gov number, NCT01751906.).

Risk Assessment in Patient Selection for Transcatheter Aortic Valve Replacement.

Risk assessment models for transcatheter aortic valve replacement (TAVR) versus surgical aortic valve replacement in high-risk patients and TAVR versus palliation in inoperable patients are based on surgical data and have limited discrimination and calibration in the setting of TAVR. Several novel risk models specifically designed for TAVR have improved discrimination over existing models but require further validation. Several clinical and echocardiographic variables, such as chronic lung disease, mitral regurgitation, and stroke volume index, influence outcomes. This article reviews current and novel risk models and important predictors of TAVR outcomes and proposes a framework to integrate them into clinical decision-making for patients with severe, symptomatic aortic stenosis.

Two-year safety and effectiveness of the platinum chromium everolimus-eluting stent for the treatment of small vessels and longer lesions.

OBJECTIVES: To report 1- and 2-year clinical outcomes of patients receiving platinum chromium everolimus-eluting stents (PtCr-EES) in the prospective, single-arm PLATINUM small vessel (SV) and long lesion (LL) studies. BACKGROUND: Small vessel diameter and long lesion length are independently associated with increased risk of adverse cardiac events after drug-eluting stent implantation. METHODS: The PLATINUM SV study enrolled 94 patients with coronary artery lesions in vessels ≥2.25 mm to <2.50 mm in diameter and ≤28 mm in length. The PLATINUM LL study enrolled 102 patients with lesions >24 to ≤34 mm long in vessels ≥2.50 to ≤4.25 mm in diameter. The primary endpoint for both studies was target lesion failure (TLF) at 1 year compared to a prespecified performance goal based on outcomes with the TAXUS Express paclitaxel-eluting stent in small vessels and long lesions. RESULTS: One-year TLF rates with the PtCr-EES were significantly (P < 0.001) lower than the predetermined performance goals: 2.4% versus 21.1% in the SV cohort and 3.2% versus 19.4% in the LL cohort. Cumulative rates of TLF to 2 years were 4.7% in the SV cohort and 8.8% in the LL cohort. No myocardial infarction or ARC definite/probable stent thromboses occurred in either cohort through 2-year follow-up. CONCLUSIONS: The clinical efficacy and safety outcomes observed in these small vessel and long lesion cohorts support the use of the PtCr-EES in the treatment of small diameter vessels and long lesions.

Outcomes after transfemoral transcatheter aortic valve replacement: a comparison of the randomized PARTNER (Placement of AoRTic TraNscathetER Valves) trial with the NRCA (Nonrandomized Continued Access) registry.

OBJECTIVES: This study sought to determine whether outcomes for transfemoral (TF) transcatheter aortic valve replacement (TAVR) differ between the randomized controlled trial (RCT) and the subsequent NRCA (Nonrandomized Continued Access) registry of the PARTNER (Placement of AoRTic TraNscathetER Valves) trial. BACKGROUND: The PARTNER RCT demonstrated that TAVR with the Edwards Sapien valve (Edwards Lifesciences, Irvine, California) is noninferior to surgery in high-risk patients and superior to standard therapy for inoperable patients. METHODS: The inclusion and exclusion criteria, data collection, monitoring, and core laboratories were the same for the RCT and NRCA registry. Baseline characteristics, procedural results, and 1-year outcomes were compared between patients undergoing TF-TAVR as part of the RCT and as part of the NRCA registry. RESULTS: In the RCT, 415 patients underwent TF-TAVR, whereas in the NRCA, 1,023 patients did. At 30 days, death, cardiac death, stroke, and transient ischemic attacks were not different in the NRCA registry than in the RCT. Major vascular complications (8.0% vs. 15.7%, p < 0.0001) and major bleeding (6.8% vs. 15.3%, p < 0.0001) were significantly lower in the NRCA registry. At 1 year, death rates were significantly lower in the NRCA cohort (19.0% vs. 25.3%, p = 0.009) and cardiac death tended to be lower (8.4% vs. 11.1%, p = 0.12). Stroke or transient ischemic attack (6.2% vs. 8.7%, p = 0.10) and stroke alone (5.0% vs. 7.1%, p = 0.13) also tended to be lower. CONCLUSIONS: The large NRCA registry demonstrates further improvement in procedural and longer-term outcomes after TF-TAVR when compared with the favorable results from the PARTNER RCT. (THE PARTNER TRIAL: Placement of AoRTic TraNscathetER Valve Trial; NCT00530894).