Noninvasive Evaluation of the Aortic Root With Multislice Computed Tomography Implications for Transcatheter Aortic Valve Replacement

ObjectivesIn the present study, the anatomy of the aortic root was assessed noninvasively with multislice computed tomography (MSCT).BackgroundTranscatheter aortic valve replacement has been proposed as an alternative to surgery in high-risk patients with severe aortic stenosis. For this procedure, detailed knowledge of aortic annulus diameters and the relation between the annulus and the coronary arteries is needed.MethodsIn 169 patients (111 men, age 54 ± 11 years), a 64-slice MSCT scan was performed for evaluation of coronary artery disease. Of these, 150 patients had no or mild aortic stenosis, and 19 patients had moderate to severe aortic stenosis. Reconstructed coronal and sagittal views were used for assessment of the aortic annulus diameter in 2 directions. In addition, the distance between the annulus and the ostium of the right and left coronary arteries and the length of the coronary leaflets were assessed. The LV outflow tract and interventricular septum were analyzed on the single oblique sagittal view at end-diastole.ResultsThe diameter of the aortic annulus was 26.3 ± 2.8 mm on the coronal view, and 23.5 ± 2.7 mm on the sagittal view. Mean difference between the 2 diameters was 2.9 ± 1.8 mm, indicating an oval shape of the aortic annulus. Mean distance between the aortic annulus and the ostium of the right coronary artery was 17.2 ± 3.3 mm, and mean distance between the annulus and the ostium of the left coronary artery was 14.4 ± 2.9 mm. In 82 patients (49%), the length of the left coronary leaflet exceeded the distance between the annulus and the ostium of the left coronary artery. There were no significant differences in the diameter of annulus, diameter of sinus of Valsalva, or the distance between the annulus, left coronary leaflet, and the ostium of the left coronary artery, between the patient with and without severe aortic stenosis.ConclusionsThe MSCT can provide detailed information on the shape of the aortic annulus and the relation between the annulus and the ostia of the coronary arteries. Thereby, MSCT may be helpful for avoiding paravalvular leakage and coronary occlusion and may facilitate the selection of candidates for transcatheter aortic valve replacement

Polymer-based or polymer-free stents in patients at high bleeding risk

Background: polymer-free drug-coated stents provide superior clinical outcomes to bare-metal stents in patients at high bleeding risk who undergo percutaneous coronary intervention (PCI) and are treated with 1 month of dual antiplatelet therapy. Data on the use of polymer-based drug-eluting stents, as compared with polymer-free drug-coated stents, in such patients are limited. Methods: in an international, randomized, single-blind trial, we compared polymer-based zotarolimus-eluting stents with polymer-free umirolimus-coated stents in patients at high bleeding risk. After PCI, patients were treated with 1 month of dual antiplatelet therapy, followed by single antiplatelet therapy. The primary outcome was a safety composite of death from cardiac causes, myocardial infarction, or stent thrombosis at 1 year. The principal secondary outcome was target-lesion failure, an effectiveness composite of death from cardiac causes, target-vessel myocardial infarction, or clinically indicated target-lesion revascularization. Both outcomes were powered for noninferiority. Results: a total of 1996 patients at high bleeding risk were randomly assigned in a 1:1 ratio to receive zotarolimus-eluting stents (1003 patients) or polymer-free drug-coated stents (993 patients). At 1 year, the primary outcome was observed in 169 of 988 patients (17.1%) in the zotarolimus-eluting stent group and in 164 of 969 (16.9%) in the polymer-free drug-coated stent group (risk difference, 0.2 percentage points; upper boundary of the one-sided 97.5% confidence interval [CI], 3.5; noninferiority margin, 4.1; P = 0.01 for noninferiority). The principal secondary outcome was observed in 174 patients (17.6%) in the zotarolimus-eluting stent group and in 169 (17.4%) in the polymer-free drug-coated stent group (risk difference, 0.2 percentage points; upper boundary of the one-sided 97.5% CI, 3.5; noninferiority margin, 4.4; P = 0.007 for noninferiority). Conclusions: among patients at high bleeding risk who received 1 month of dual antiplatelet therapy after PCI, use of polymer-based zotarolimus-eluting stents was noninferior to use of polymer-free drug-coated stents with regard to safety and effectiveness composite outcomes. (Funded by Medtronic; ONYX ONE ClinicalTrials.gov number, NCT03344653.)