No abstract

T ranscatheter aortic valve replacement (TAVR) has revolutionized management of elderly patients with severe aortic stenosis, 1,2 but post-TAVR neurological events remain a concern for patients and physicians. Although occurrence of post-TAVR stroke has fallen from ≈5% in initial trials to 3% in recent reports, reducing this risk is essential for advancing this technology into lower-risk patient cohorts. See Editorial by Dangas and GiustinoUnderstanding the mechanisms of neurological events is critical for developing strategies for reducing their occurrence. Despite several attempts to identify procedure and patient characteristics that may lead to neurological events, the field remains somewhat controversial.3,4 One controversy is the timing of neurological events and its relationship to procedural embolization.5 Different reports have suggested that up to half of the events may be unrelated to procedural embolization, although small numbers of patients and events, Background-Prior studies of stroke and transient ischemic attack (TIA) after transcatheter aortic valve replacement (TAVR) are limited by reporting and follow-up variability. This is a comprehensive analysis of time-related incidence, risk factors, and outcomes of these events. Methods and Results-From 17).Stroke and TIA were associated with lower 1-year survival than expected (TF 47% after stroke versus 82%, and 64% after TIA versus 83%; TA 53% after stroke versus 80%, and 64% after TIA versus 83%). Risk factors for early stroke after TA-TAVR included more postdilatations, pure aortic stenosis without regurgitation, and possibly more pacing runs, earlier date of procedure, and no dual antiplatelet therapy; high pre-TAVR aortic peak gradient was a risk factor for stroke early after TF-TAVR. Conclusions-Risk of stroke or TIA is highest early after TAVR and is associated with increased 1-year mortality.Modifications of TAVR, emboli-prevention devices, and better intraprocedural pharmacological protection may mitigate this risk. Clinical Trial Registration-URL: http://www.clinicaltrials.gov. Unique identifier: NCT00530894.(Circ Cardiovasc Interv. 2016;9:e002981.

Background Data regarding the risk of aortic dissection in patients with bicuspid aortic valve and large ascending aortic diameter are limited, and appropriate timing of prophylactic ascending aortic replacement lacks consensus. Thus our objectives were to determine the risk of aortic dissection based on initial cross-sectional imaging data and clinical variables and to isolate predictors of aortic intervention in those initially prescribed serial surveillance imaging. Methods From January 1995 to January 2014, 1,181 patients with bicuspid aortic valve underwent cross-sectional computed tomography (CT) or magnetic resonance imaging (MRI) to ascertain sinus or tubular ascending aortic diameter greater than or equal to 4.7 cm. Random Forest classification was used to identify risk factors for aortic dissection, and among patients undergoing surveillance, time-related analysis was used to identify risk factors for aortic intervention. Results Prevalence of type A dissection that was detected by imaging or was found at operation or on follow-up was 5.3% (n = 63). Probability of type A dissection increased gradually at a sinus diameter of 5.0 cm—from 4.1% to 13% at 7.2 cm—and then increased steeply at an ascending aortic diameter of 5.3 cm—from 3.8% to 35% at 8.4 cm—corresponding to a cross-sectional area to height ratio of 10 cm2/m for sinuses of Valsalva and 13 cm2/m for the tubular ascending aorta. Cross-sectional area to height ratio was the best predictor of type A dissection (area under the curve [AUC] = 0.73). Conclusions Early prophylactic ascending aortic replacement in patients with bicuspid aortic valve should be considered at high-volume aortic centers to reduce the high risk of preventable type A dissection in those with aortas larger than approximately 5.0 cm or with a cross-sectional area to height ratio greater than approximately 10 cm2/m.

Technical performance learning curves exist for TF-TAVR; procedural efficiency increased with experience, with concomitant decreases in radiation and contrast media exposure. The number of cases needed to achieve efficiency decreased progressively, with optimal procedural performance reached after approximately 25 cases for late-entering institutions. Knowledge and experience accumulated by early TF-TAVR institutions were disseminated, shortening the learning curve of late-entering institutions. Technological advances resulting from learning during the trial moved the field from initial conservative surgical cut-down to percutaneous access for most patients. © 2015 Wiley Periodicals, Inc.

By end of trial, a consistent low risk of adverse events was achieved after ∼26 cases. However, these improved results were due to change in patient risk profile; outcomes were not linked to the technical performance learning curve. © 2015 Wiley Periodicals, Inc.