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Objectives: Computed tomography (CT) provides excellent anatomy assessment of the aortic annulus (AoA) and is utilized for pre-procedural planning of transcatheter aortic valve implantation (TAVI). We sought to investigate if geometrical characteristics of the AoA determined by CT may represent predictors of structural valve degeneration (SVD) in patients undergoing TAVI with balloon-expandable valves., Methods: This is a retrospective study on 124 consecutive patients (mean age: 79 ± 7 years; female: 61%) undergoing balloon-expandable TAVI prospectively enrolled in a registry. AoA maximum diameter (D max ), minimum diameter (D min ), and area were assessed using pre-procedural CT. SVD was identified during follow-up with transthoracic echocardiography documenting structural prosthetic valve abnormalities with or without hemodynamic changes., Results: The mean follow-up was 5.9 ± 1.7 years. SVD was found in 48 out of 124 patients (38%). AoA D max , D min , and area were significantly smaller in patients with SVD compared to patients without SVD (25.6 ± 2.2 mm vs. 27.1 ± 2.8 mm, p = 0.012; 20.5 ± 2.1 mm vs. 21.8 ± 2.1 mm, p = 0.001 and 419 ± 77 mm 2 vs. 467 ± 88 mm 2 , p = 0.002, respectively). At univariable analysis, female sex, BSA, 23-mm prosthetic valve size, D max < 27.1 mm, and a D min < 19.9 mm were associated with SVD, whereas at multivariable analysis, only D min < 19.9 mm (OR = 2.873, 95% CI: 1.191-6.929, p = 0.019) and female sex (OR = 2.659, 95% CI: 1.095-6.458, p = 0.031) were independent predictors of SVD., Conclusions: Female sex and AoA D min < 19.9 mm are associated with SVD in patients undergoing TAVI with balloon-expandable valves. When implanting large prostheses in order to avoid paraprosthetic regurgitation, caution should be observed due to the risk of excessive stretching of the AoA D min, which may play a role in SVD., Key Points: • Long-term durability is a concern for transcatheter aortic valve bioprosthesis. • CT provides an excellent assessment of the aortic annulus's geometrical characteristics for prosthesis sizing before transcatheter aortic valve implantation (TAVI). • Female sex and a small minimum aortic annulus diameter measured with CT are independent predictors of structural valve degeneration in patients undergoing TAVI with balloon-expandable valves., (© 2022. The Author(s), under exclusive licence to European Society of Radiology.)

Numerical models are increasingly used in the cardiovascular field to reproduce, study and improve devices and clinical treatments. The recent literature involves a number of patient-specific models replicating the transcatheter aortic valve implantation procedure, a minimally invasive treatment for high-risk patients with aortic diseases. The representation of the actual patient's condition with truthful anatomy, materials and working conditions is the first step toward the simulation of the clinical procedure. The aim of this work is to quantify how the quality of routine clinical data, from which the patient-specific models are built, affects the outputs of the numerical models representing the pathological condition of stenotic aortic valve. Seven fluid-structure interaction (FSI) simulations were performed, completed with a sensitivity analysis on patient-specific reconstructed geometries and boundary conditions. The structural parts of the models consisted of the aortic root, native tri-leaflets valve and calcifications. Ventricular and aortic pressure curves were applied to the fluid domain. The differences between clinical data and numerical results for the aortic valve area were less than 2% but reached 12% when boundary conditions and geometries were changed. The difference in the aortic stenosis jet velocity between measured and simulated values was less than 11% reaching 27% when the geometry was changed. The CT slice thickness was found to be the most sensitive parameter on the presented FSI numerical model. In conclusion, the results showed that the segmentation and reconstruction phases need to be carefully performed to obtain a truthful patient-specific domain to be used in FSI analyses., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Purpose: Transcatheter aortic valve replacement (TAVR) is a minimally invasive treatment for high-risk patients with aortic diseases. Despite its increasing use, many influential factors are still to be understood and require continuous investigation. The best numerical approach capable of reproducing both the valves mechanics and the hemodynamics is the fluid-structure interaction (FSI) modeling. The aim of this work is the development of a patient-specific FSI methodology able to model the implantation phase as well as the valve working conditions during cardiac cycles., Methods: The patient-specific domain, which included the aortic root, native valve and calcifications, was reconstructed from CT images, while the CAD model of the device, metallic frame and pericardium, was drawn from literature data. Ventricular and aortic pressure waveforms, derived from the patient's data, were used as boundary conditions. The proposed method was applied to two real clinical cases, which presented different outcomes in terms of paravalvular leakage (PVL), the main complication after TAVR., Results: The results confirmed the clinical prognosis of mild and moderate PVL with coherent values of regurgitant volume and effective regurgitant orifice area. Moreover, the final release configuration of the device and the velocity field were compared with postoperative CT scans and Doppler traces showing a good qualitative and quantitative matching., Conclusion: In conclusion, the development of realistic and accurate FSI patient-specific models can be used as a support for clinical decisions before the implantation.

The incidental finding of a severe occlusive disease of the aorta (coral reef aorta) during the assessment for transcatheter aortic valve replacement in a 75-year-old woman with severe aortic stenosis complicated the process for the Heart Team and led to the consideration of a different access route to find the safest and most appropriate strategy of intervention. A successful transapical transcatheter aortic valve replacement was eventually performed. Coral reef aorta, although rare, is associated with great morbidity and mortality, and it needs to be recognized when planning for intravascular procedures, both for a safer selection of treatment approach and for the prevention of intraprocedural and postprocedural morbidities., (Copyright © 2019 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.)

Objectives: We sought to determine the impact of aortic root calcium on the risk of significant paravalvular regurgitation (sPAR) in transcatheter aortic valve replacement (TAVR)., Methods: In 302 consecutive patients from 3 centers, aortic root calcium was quantified volumetrically on pre-TAVR multidetector computed tomography (MDCT) in three regions: 1) the aortic valve region, 2) the overall left ventricular outflow tract (LVOT) and 3) the upper LVOT. Transcathether heart valve (THV) oversizing was calculated as (THV nominal area/MDCT annular area-1) × 100. The study endpoint sPAR was a composite of post-dilatation (PD) and PAR > mild., Results: sPAR occurred in 15% (46/302) of patients. Upper LVOT calcium volume was more predictive of sPAR than overall LVOT calcium volume, with an area under the receiver operating curve (AUC) (95% confidence interval [CI]) of 0.80 (0.67-0.89) vs. 0.60 (0.51-0.70); p = 0.0001. The optimal cut-off calcium volume thresholds determined from receiver operating curves were 21 mm 3 and 30 mm 3 for upper LVOT and overall LVOT calcium, respectively. Upper LVOT calcium ≥ 21 mm 3 , but not overall LVOT calcium ≥ 30 mm 3 , independently predicted sPAR, odds ratio (95%CI): 9.5 (4.1-22.3) vs 1.6 (0.6-2.7). Upper LVOT calcium was more predictive of sPAR in patients with THV oversizing ≥ 13% compared to patients with THV oversizing <13%, AUC (95% CI): 0.83 (0.72-0.93) vs. 0.67 (0.51-0.74); p < 0.0001., Conclusions: Upper LVOT calcium predicts more-than-mild paravalvular regurgitation following TAVR or the need for postdilatation. Upper LVOT calcium is most predictive of paravalvular regurgitation in the event of THV oversizing ≥ 13%., (Copyright © 2018 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.)

Background: Coronary artery disease (CAD) and aortic stenosis share pathophysiological mechanisms and risk factors. We evaluated the clinical utility of coronary computed tomography angiography (CTA) to identify CAD and revascularization requirement in patients with severe aortic stenosis considered for transcatheter aortic valve replacement (TAVR)., Methods: Consecutive patients without known CAD underwent calcium scoring, CTA and invasive coronary angiography (ICA). A second-generation dual-source CT scanner was used. ICA-quantitative coronary angiography (QCA) served as reference standard. CAD was reported using a lenient threshold of ≥50% and a stricter threshold of ≥70% diameter reduction. Findings of ≥70% diameter reduction and of high-risk CAD were used to predict revascularization., Results: The study included 140 patients [68 males; 82.3 (7.7) years]. CAD defined by the 50% threshold on ICA was found in 58/140 (41%) patients. CAD by the 70% threshold was found in 23/140 (16%) patients. High-risk CAD was found in 16/140 (11%) patients. CTA and ICA had similar odd-ratios of 3.22 (1.26-8.23) and 4.62 (1.64-13.05), respectively, in predicting revascularization. Forty-two/140 (30%) patients had <400 Agatston calcium score, 98/140 (70%) patients had ≥400 calcium score. The diagnostic performance of CTA in the low calcium score group was better than the high calcium score group (AUC 0.81 vs. 0.63)., Conclusion: CTA remained questionable to rule-out CAD as gatekeeper to ICA in TAVR candidates who had severe coronary calcifications. In patients with less severe coronary calcifications, accounting for 30% of participants in this study, CTA may play a clinical role., (Copyright © 2017 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.)

Aims: To evaluate the feasibility of procedural planning for transcatheter aortic valve implantation (TAVI) using rotational angiography (R-angio) by comparison with multislice computed tomography (MSCT) and to investigate determinants of the image quality of R-angio., Methods and Results: Patients who underwent R-angio of the left ventricle and cardiac MSCT were eligible. R-angio acquisition was performed during contrast injection through a 6F pigtail catheter positioned in the left ventricle. On 3D R-angio and MSCT data sets, diameter measurements were made on short-axis images at the level of the aortic annulus (D(perimeter), D(area)), ascending aorta, sino-tubular junction (ST-junction), and the sinus of Valsalva. At the level of the aortic annulus, diagnostic image quality was obtained in 49 of 56 patients. In all patients with a body mass index (BMI) < 29 kg/m(2), image quality was acceptable whether or not rapid pacing was used. In patients with BMI ≥ 29 kg/m(2), the image quality was poor in 1 of 9 (11%) who were rapidly paced compared with 6 of 12 (50%) who were not. The correlation between R-angio and MSCT measurements was high for aortic annulus D(perimeter), D(area), ST-junction, Valsalva sinus, and ascending aorta (respectively, R = 0.90, 0.90, 0.91, 0.92, and 0.89). The correlations improved further when the analysis was limited to patients with a BMI < 29 kg/m(2) (respectively, 0.92, 0.92, 0.92, 0.92, and 0.93)., Conclusion: R-angio of the left ventricle allows precise measurement of the aortic root and annulus and was feasible for sizing at the time of TAVI. Diagnostic image quality was obtained without rapid pacing in all patients with a BMI < 29 kg/m(2).

Objectives/background: Congenital aortic stenosis (AS) is the most common obstructive left heart lesion in the young adult population and often complicated by aortic dilatation. Our objective was to evaluate accuracy of aortic imaging with transthoracic echocardiography (TTE) compared with cardiac magnetic resonance (CMR)., Methods: Aortic diameters were measured at 4 levels by CMR and TTE. Agreement and concordance were assessed by Pearson's correlation and Bland-Altman analysis., Results: Fifty-nine patients (age 33 ± 8 years; 66% male) with congenital AS and a bicuspid aortic valve (BAV) were included. Aortic diameters were generally smaller with TTE than with CMR. The best correlation was found at the level of the sinotubular junction (R(2) = 0.78) with a bias of 1.46 mm (limits of agreement: -5.47 to +8.39 mm). In patients with an aortic aneurysm >40 mm (n = 29) the correlation and agreement between TTE and CMR were found to be less good when compared with patients with normal aortic diameters, especially at the level of the proximal ascending aorta. The correlation and agreement between both imaging modalities were better in patients with type 1 BAV compared with type 2 BAV. Intra- and interobserver variability was smaller with CMR (1.8-5.9%) compared with TTE (6.9-15.0%)., Conclusions: CMR was found to be superior to TTE for imaging of the aorta in patients with congenital AS, especially at the level of the proximal ascending aorta when an aortic aneurysm is present. Therefore, ideally CMR should be performed at least once to ensure an ascending aortic aneurysm is not missed., (© 2013, Wiley Periodicals, Inc.)

Background: The aim of this study was to evaluate the natural progression of aortic dilatation and its association with aortic valve stenosis (AoS) in patients with bicuspid aortic valve (BAV)., Methods: Prospective study of aorta dilatation in patients with BAV and AoS using cardiac magnetic resonance (CMR). Aortic root, ascending aorta, aortic peak velocity, left ventricular systolic and diastolic function and mass were assessed at baseline and at 3-year follow-up., Results: Of the 33 enrolled patients, 5 needed surgery, while 28 patients (17 male; mean age: 31 ± 8 years) completed the study. Aortic diameters significantly increased at the aortic annulus, sinus of Valsalva and tubular ascending aorta levels (P < 0.050). The number of patients with dilated tubular ascending aortas increased from 32 % to 43 %. No significant increase in sino-tubular junction diameter was observed. Aortic peak velocity, ejection fraction and myocardial mass significantly increased while the early/late filling ratio significantly decreased at follow-up (P < 0.050). The progression rate of the ascending aorta diameter correlated weakly with the aortic peak velocity at baseline (R (2) = 0.16, P = 0.040)., Conclusion: BAV patients with AoS showed a progressive increase of aortic diameters with maximal expression at the level of the tubular ascending aorta. The progression of aortic dilatation correlated weakly with the severity of AoS.

Aims: We compared the measurement of aortic leaflet calcification on contrast and non-contrast MSCT and investigated predictors of the need for balloon post-dilatation after TAVI., Methods and Results: In 110 patients, who had TAVI with a Medtronic CoreValve prosthesis (MCS) for symptomatic aortic stenosis, calcification of the aortic root was measured on non-contrast MSCT (conventionally) and on contrast MSCT (signal attenuation >450 Houndsfield units). Calcium volume was underestimated on contrast- when compared to non-contrast MSCT: median (IQ-range)=759 (466 to 1295) vs. 2016 (1376 to 3262) and the difference between the two methods increased with higher calcium volumes (correlation coefficient r=0.90). Calcium mass was only slightly underestimated on contrast vs. non-contrast MSCT: median (IQ-range)=441 (268 to 809) vs. 555 (341 to 950) and there was no association between the differences and increasing calcium mass (r=0.17). Balloon post-dilatation was performed for significant aortic regurgitation after TAVI in 11 of 110 patients. When compared to controls, the patients who required balloon post-dilatation had higher aortic leaflet calcium on contrast CT (p<0.01), higher aortic annulus diameters (p<0.01) and higher annulus to prosthesis area ratio (p=0.01). ROC curves demonstrated that aortic root or aortic leaflet calcium measured on either contrast- or non-contrast MSCT showed excellent discrimination for the requirement of balloon post-dilatation (area under ROC >0.80 for all), whereas the discriminatory value of aortic annulus dimensions was moderate (area under ROC=0.69) and that of prosthesis to annulus ratio was poor (area under ROC=0.36)., Conclusions: Dense aortic leaflet calcification measured on contrast MSCT discerned well the need for balloon post-dilatation after TAVI with an MCS for significant PAR. Non-contrast MSCT may no longer be needed to quantify aortic root calcium before TAVI.

Background: To investigate the causes of paravalvular aortic regurgitation (PAR) after the implantation of the Medtronic CoreValve prosthesis (MCRS)., Methods and Results: Fifty-six patients underwent MSCT before TAVI with a MCRS and PAR was assessed with transthoracic echocardiography (TTE) between 5 and 10 days after TAVI. The aortic annulus smallest and largest orthogonal diameters and the mean diameter from the area were determined on MSCT on an axial image at the nadir of all three native leaflets. PAR was related to relevant anatomical structures on MSCT according to a clockface in the orientation of the parasternal short axis view on TTE. PAR ≥ 1 was present in 25% of the patients and was associated with a larger annulus, a lower degree of over sizing and with more aortic root calcification. On MSCT post TAVI malapposition was seen predominantly at the aorto-mitral fibrous continuity and the aspect of the largest diameter of the aortic annulus on the inside curve of the ascending aorta. PAR was predominantly seen at these two anatomic locations and less frequent in the area that contains the ventricular membranous septum and the area between the non- and right coronary sinus., Conclusions: Mild to moderate PAR is common after TAVI with the MCRS. The availability of additional (larger) prosthesis sizes in combination with improved sizing based on mean annulus diameter (e.g., D(CSA)) may help to reduce PAR., (Copyright © 2011 Wiley-Liss, Inc.)