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Improved Registration of 3D CT Angiography with X-ray Fluoroscopy for Image Fusion During Transcatheter Aortic Valve Implantation
Published on: June 3, 2018
Predicting vascular complications during transfemoral transcatheter aortic valve replacement using computed
Amar Krishnaswamy1, Akhil Parashar, Shikhar Agarwal
1Department of Cardiovascular Medicine, Cleveland Clinic, Cleveland, Ohio.
Insights
Computed tomography (CT) imaging can predict vascular complications in transcatheter aortic valve replacement (TAVR). The sheath to femoral artery area ratio (SFAAR) is a more accurate predictor than the sheath to femoral artery diameter ratio (SFAR).
Area of Science:
- Cardiovascular Imaging
- Interventional Cardiology
- Vascular Surgery
Background:
- Vascular complications are a concern during transcatheter aortic valve replacement (TAVR).
- Computed tomography (CT) imaging has not been systematically evaluated for predicting these complications.
Purpose of the Study:
- To investigate the utility of CT-derived iliofemoral measurements in predicting vascular complications during transfemoral TAVR (TF-TAVR).
- To compare the predictive accuracy of the sheath to femoral artery diameter ratio (SFAR) and the sheath to femoral artery area ratio (SFAAR).
Main Methods:
- Retrospective analysis of clinical data and iliofemoral CT angiograms from 255 patients undergoing TF-TAVR.
- Calculation of SFAR (sheath outer diameter to femoral minimal lumen diameter) and SFAAR (sheath area to femoral minimal lumen area).
- Receiver operating characteristic (ROC) curve analysis and multivariable modeling to assess predictive values.
Main Results:
- Eleven percent of patients experienced vascular complications, mostly managed percutaneously.
- SFAAR of 1.35 predicted vascular complications with 78.6% sensitivity.
- SFAR of 1.45 predicted complications with 64.2% sensitivity.
- Both SFAR and SFAAR were significant independent predictors of vascular complications in multivariable analysis.
Conclusions:
- CT-derived SFAAR (1.35) and SFAR (1.45) are significant predictors of vascular complications in TF-TAVR.
- CT-based area measurements, considering vessel ellipticity, may offer a more accurate pre-procedural screening tool for TF-TAVR patients.
Background:
Computed tomography (CT) imaging has not been systematically studied for predicting vascular complications during transcatheter aortic valve replacement (TAVR).
Methods:
Clinical data were obtained from the electronic medical record and analysis was performed for each individual patient's iliofemoral CT angiogram. Sheath : femoral artery diameter ratio (SFAR) and sheath : femoral artery area ratio (SFAAR) were defined as the ratio of the sheath outer diameter to the femoral minimal lumen diameter (MLD) and sheath area to the femoral minimal lumen area (MLA), respectively.
Results:
A total of 255 patients underwent TF-TAVR with a 30-day mortality of 0.4% and 30-day stroke rate of 1.6%. Twenty-eight (11%) patients suffered a vascular complication, the majority of whom (82%) were managed percutaneously. Receiver operating characteristic (ROC) curve analysis demonstrated an SFAAR of 1.35 to predict the occurrence of vascular complications with a sensitivity of 78.6%. By comparison, similar analysis using SFAR provided a value of 1.45 with sensitivity of 64.2%. Multivariable modeling confirmed SFAR [OR (95% CI): 8.3(1.8-39.1)] and log-transformed SFAAR [OR (95% CI): 40.1 (2.4-650.0)] as significant predictors of vascular complication.
Conclusions:
Using CT analysis, an SFAR of 1.45 and an SFAAR of 1.35 are each significant predictors of vascular complications among patients undergoing TF-TAVR. Utilization of CT-based area may provide a more accurate screen for patients undergoing evaluation for TF-TAVR as it takes into consideration the elliptical nature of the vessel. © 2014 Wiley Periodicals, Inc.
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