Periprocedural Assessment of Paravalvular Regurgitation After Transcatheter Aortic Valve Replacement Using Diastolic Delta and Videodensitometry
The hemodynamic index diastolic delta and videodensitometry have an equally high predictive value for relevant paravalvular regurgitation after transcatheter aortic valve replacement as assessed with gold‐standard cardiac magnetic resonance. The combination of both modalities increases the predictive value for relevant paravalvular regurgitation. 

These findings suggest that the combined use of diastolic delta and videodensitometry is superior in predicting relevant paravalvular regurgitation after transcatheter aortic valve replacement than the individual modalities alone. Future prospective studies addressing the accuracy and feasibility of the combined use of diastolic delta and videodensitometry are needed. 

The data that support the findings of this study are available from the corresponding author upon reasonable request. This study was performed in accordance with the Strengthening the Reporting of Observational Studies in Epidemiology guidelines for reporting observational studies. Population and Design The APPOSE trial was an investigator‐initiated, prospective single‐center study evaluating the accuracy of periprocedural assessment of hemodynamic indices to predict relevant PVR as quantified by CMR at 1 month after TAVR. In brief, patients were eligible for the study if they underwent TAVR for severe symptomatic aortic stenosis, with main exclusion criteria a preexisting cardiac device, left ventricular ejection fraction <30%, and a serum creatinine >250 μmol/L or end‐stage renal disease. In all patients, a self‐expanding valve (Portico; Abbot Structural Heart, St. Paul, MN) was implanted, with valve sizes ranging between 23 and 29 mm. Between November 2019 and October 2021, 103 patients provided written informed consent for the APPOSE trial. A total of 77 patients were included in the primary analysis. Patients were eligible for the present substudy after successful quantification of PVR by both CMR and videodensitometry. The study protocol was approved by the local Medical Research Ethics Committee and by the institutional review board of the Radboud University Medical Center. Hemodynamic Measurements The TAVR procedure was performed according to routine local protocol, which has been described previously. Four hemodynamic indices (DD, heart rate–adjusted DD, aortic regurgitation index [ARI], and ARI ratio) were derived from the simultaneous pressure measurements in the aorta and left ventricle. These pressure measurements were performed at baseline (i.e., before pre‐dilation), directly after implantation of the Portico valve, and (if applicable) after post‐dilation. The hemodynamic measurements at baseline and after final TAVR result were used for calculation of the hemodynamic indices. For each hemodynamic index, the averaged pressures were used of at least 3 representative cardiac cycles during sinus rhythm, or at least 5 representative cycles during atrial fibrillation. Performing these pressure measurements requires ≈2 to 3 minutes, including the positioning of the fluid‐filled pigtail catheters in the aorta and left ventricle, and recording of the pressure measurements. The 4 hemodynamic indices were computed using the following calculations: DD: end‐diastolic blood pressure−left ventricular end‐diastolic pressure Heart rate‐adjusted DD: (DD/heart rate)×80 ARI: (DD/systolic blood pressure)×100 ARI ratio: ARI after implantation/ARI before implantation PVR Assessment Using Quantitative Videodensitometry The quantitative videodensitometry technique was described previously. In brief, time–density curves are generated in the left ventricular outflow tract (LVOT) (region of interest) and in the aortic root where the contrast is injected (reference area). From these time–density curves, the area under the time‐density curve (AUC) is automatically computed to represent the time–density integral. The regurgitant fraction (LVOT‐AR) is calculated by dividing the AUC of the LVOT by the AUC of the aortic root. The following previously validated cutoff values to classify PVR severity were used : RF ≤6% indicates none/trace PVR, RF 7% to ≤17% indicates mild PVR, and RF >17% indicates ≥ moderate PVR. For videodensitometric analysis, at least 3 cardiac cycles after contrast injection are averaged, irrespective of the heart rhythm. The anonymized Digital Imaging and Communications in Medicine files of the TAVR procedure were shared with the CORRIB Core Laboratory (University of Galway, Galway, Ireland) for independent offline (retrospective) analysis of the final aortic angiograms (i.e., after post‐dilation if applicable) after implantation of the Portico valve. Quantitative videodensitometry was performed using CAAS A‐Valve version 2.1.2 (Pie Medical Imaging, Maastricht, the Netherlands) to assess PVR severity expressed as regurgitant fraction. This software has a low system requirement and demands no additional equipment. The analysis by a trained individual requires ≈2 to 4 minutes, including saving the results in a PDF, XML, or Digital Imaging and Communications in Medicine format. CMR Measurements All patients were scanned 4 to 6 weeks after TAVR on a commercially available 1.5 T CMR scanner (MAGNETOM Avanto; Siemens Healthcare, Erlangen, Germany). Details on the CMR acquisition and analysis are described elsewhere. , Briefly, flow acquisitions were performed during successive end‐expiratory breath‐holds using a high velocity encoding of ≥180 cm/s to quantify the forward (i.e., high‐flow) volume, and a low velocity encoding of 75 cm/s to quantify the regurgitant (i.e., low‐flow) volume. The regurgitant fraction was calculated by dividing the regurgitant volume (low velocity encoding) by the forward volume (high velocity encoding), multiplied by 100. Image analysis was performed offline with Medis Suite MR version 4.0.24.4 (Medis Medical Imaging, Leiden, the Netherlands). End Points End points were (1) the correlation between hemodynamic indices and LVOT‐AR; (2) the predictive value of hemodynamic indices alone, LVOT‐AR alone, and the combination of both modalities for the occurrence of relevant PVR 1 month after TAVR as quantified by CMR; and (3) the concordance, positive predictive value (PPV), and negative predictive value (NPV) of the individual modalities and its combination for the occurrence of relevant PVR 1 month after TAVR. Cutoffs associated with relevant PVR were ≤32 mm Hg for DD and>17% for LVOT‐AR. , Statistical Analysis Data are presented as mean±SD, or number (percentage), as appropriate. Pearson's correlation coefficients were used to quantify the correlation between continuous variables (regarding the variables DD, LVOT‐AR, and CMR‐RF). The area under receiver operating characteristic curve was used to assess the predictive value of the (1) DD, (2) LVOT‐AR, and (3) combination of the DD and LVOT‐AR for relevant PVR (CMR‐RF >20%). To allow receiver operating characteristic analysis, relevant PVR was defined as CMR‐RF >20%. Net reclassification improvement (NRI) and integrated discrimination improvement (IDI) were calculated to assess the incremental value of the combined versus isolated use of DD and LVOT‐AR for the prediction of relevant PVR. All statistical tests were 2‐tailed, and a P value of <0.05 was considered statistically significant. Analyses were performed in SPSS Statistics version 27.0.1.0 (IBM Corporation, Armonk, NY). 

The APPOSE trial was an investigator‐initiated, prospective single‐center study evaluating the accuracy of periprocedural assessment of hemodynamic indices to predict relevant PVR as quantified by CMR at 1 month after TAVR. In brief, patients were eligible for the study if they underwent TAVR for severe symptomatic aortic stenosis, with main exclusion criteria a preexisting cardiac device, left ventricular ejection fraction <30%, and a serum creatinine >250 μmol/L or end‐stage renal disease. In all patients, a self‐expanding valve (Portico; Abbot Structural Heart, St. Paul, MN) was implanted, with valve sizes ranging between 23 and 29 mm. Between November 2019 and October 2021, 103 patients provided written informed consent for the APPOSE trial. A total of 77 patients were included in the primary analysis. Patients were eligible for the present substudy after successful quantification of PVR by both CMR and videodensitometry. The study protocol was approved by the local Medical Research Ethics Committee and by the institutional review board of the Radboud University Medical Center. 

The TAVR procedure was performed according to routine local protocol, which has been described previously. Four hemodynamic indices (DD, heart rate–adjusted DD, aortic regurgitation index [ARI], and ARI ratio) were derived from the simultaneous pressure measurements in the aorta and left ventricle. These pressure measurements were performed at baseline (i.e., before pre‐dilation), directly after implantation of the Portico valve, and (if applicable) after post‐dilation. The hemodynamic measurements at baseline and after final TAVR result were used for calculation of the hemodynamic indices. For each hemodynamic index, the averaged pressures were used of at least 3 representative cardiac cycles during sinus rhythm, or at least 5 representative cycles during atrial fibrillation. Performing these pressure measurements requires ≈2 to 3 minutes, including the positioning of the fluid‐filled pigtail catheters in the aorta and left ventricle, and recording of the pressure measurements. The 4 hemodynamic indices were computed using the following calculations: DD: end‐diastolic blood pressure−left ventricular end‐diastolic pressure Heart rate‐adjusted DD: (DD/heart rate)×80 ARI: (DD/systolic blood pressure)×100 ARI ratio: ARI after implantation/ARI before implantation 

Assessment Using Quantitative Videodensitometry The quantitative videodensitometry technique was described previously. In brief, time–density curves are generated in the left ventricular outflow tract (LVOT) (region of interest) and in the aortic root where the contrast is injected (reference area). From these time–density curves, the area under the time‐density curve (AUC) is automatically computed to represent the time–density integral. The regurgitant fraction (LVOT‐AR) is calculated by dividing the AUC of the LVOT by the AUC of the aortic root. The following previously validated cutoff values to classify PVR severity were used : RF ≤6% indicates none/trace PVR, RF 7% to ≤17% indicates mild PVR, and RF >17% indicates ≥ moderate PVR. For videodensitometric analysis, at least 3 cardiac cycles after contrast injection are averaged, irrespective of the heart rhythm. The anonymized Digital Imaging and Communications in Medicine files of the TAVR procedure were shared with the CORRIB Core Laboratory (University of Galway, Galway, Ireland) for independent offline (retrospective) analysis of the final aortic angiograms (i.e., after post‐dilation if applicable) after implantation of the Portico valve. Quantitative videodensitometry was performed using CAAS A‐Valve version 2.1.2 (Pie Medical Imaging, Maastricht, the Netherlands) to assess PVR severity expressed as regurgitant fraction. This software has a low system requirement and demands no additional equipment. The analysis by a trained individual requires ≈2 to 4 minutes, including saving the results in a PDF, XML, or Digital Imaging and Communications in Medicine format. 

Measurements All patients were scanned 4 to 6 weeks after TAVR on a commercially available 1.5 T CMR scanner (MAGNETOM Avanto; Siemens Healthcare, Erlangen, Germany). Details on the CMR acquisition and analysis are described elsewhere. , Briefly, flow acquisitions were performed during successive end‐expiratory breath‐holds using a high velocity encoding of ≥180 cm/s to quantify the forward (i.e., high‐flow) volume, and a low velocity encoding of 75 cm/s to quantify the regurgitant (i.e., low‐flow) volume. The regurgitant fraction was calculated by dividing the regurgitant volume (low velocity encoding) by the forward volume (high velocity encoding), multiplied by 100. Image analysis was performed offline with Medis Suite MR version 4.0.24.4 (Medis Medical Imaging, Leiden, the Netherlands). 

End points were (1) the correlation between hemodynamic indices and LVOT‐AR; (2) the predictive value of hemodynamic indices alone, LVOT‐AR alone, and the combination of both modalities for the occurrence of relevant PVR 1 month after TAVR as quantified by CMR; and (3) the concordance, positive predictive value (PPV), and negative predictive value (NPV) of the individual modalities and its combination for the occurrence of relevant PVR 1 month after TAVR. Cutoffs associated with relevant PVR were ≤32 mm Hg for DD and>17% for LVOT‐AR. , 

Data are presented as mean±SD, or number (percentage), as appropriate. Pearson's correlation coefficients were used to quantify the correlation between continuous variables (regarding the variables DD, LVOT‐AR, and CMR‐RF). The area under receiver operating characteristic curve was used to assess the predictive value of the (1) DD, (2) LVOT‐AR, and (3) combination of the DD and LVOT‐AR for relevant PVR (CMR‐RF >20%). To allow receiver operating characteristic analysis, relevant PVR was defined as CMR‐RF >20%. Net reclassification improvement (NRI) and integrated discrimination improvement (IDI) were calculated to assess the incremental value of the combined versus isolated use of DD and LVOT‐AR for the prediction of relevant PVR. All statistical tests were 2‐tailed, and a P value of <0.05 was considered statistically significant. Analyses were performed in SPSS Statistics version 27.0.1.0 (IBM Corporation, Armonk, NY). 

Baseline Characteristics Baseline characteristics of the 51 patients are presented in Table . Mean age was 80.6±5.2 years and 45.1% of patients were men. Mean Society of Thoracic Surgeons score was 2.50±0.92 and 39.2% of patients were in New York Heart Association function class III or IV. Mean left ventricular ejection fraction was 54.0±9.1%, with a mean aortic valve area and aortic valve mean gradient of 0.77±0.18 cm 2 and 45.5±12.9 mm Hg, respectively. Procedural Characteristics and PVR Assessment Details on procedural characteristics are provided in Table . Post‐implantation values of the 4 hemodynamic indices were the following: 40±11 mm Hg for DD, 42±13 mm Hg/bpm for heart rate‐adjusted‐DD, 29±10 for ARI, and 0.95±0.52 for ARI ratio. Post‐implantation DD was ≤32 mm Hg in 15 (29.4%) patients. The aortic angiogram was analyzable in 51 of 77 patients (analyzability, 66.2%). The reasons for the non‐analyzability of videodensitometry are provided in Table . Mean LVOT‐AR was 8.2%±7.8%. Videodensitometry categorized 26 (51.0%) cases as none/trace PVR, 17 (33.3%) as mild PVR, and 8 (15.7%) as ≥ moderate PVR. Mean duration between TAVR and CMR was 40±15 days. The average CMR‐RF was 11.7±9.6%, with 9 (17.6%) cases with CMR‐RF >20%. In all of the patients with CMR‐RF >20%, this was related to PVR and not to central aortic regurgitation. There were 5 cases with relevant PVR on CMR but not on LVOT‐AR (details shown in Table ). PVR assessment by TTE during follow‐up was performed on the same day as the CMR assessment, and graded PVR as none/trace in 25 (49.0%) patients, mild in 25 (49.0%) patients, and moderate in 1 (2.0%) patient. Comparison Between DD and Videodensitometry The (inverse) correlation between DD and LVOT‐AR was −0.36 ( P =0.01) (Figure ). The agreement (i.e., either DD ≤32 mm Hg and LVOT‐AR >17%, or DD >32 mm Hg and LVOT‐AR ≤17%) between DD and LVOT‐AR was 70.6%. Mean DD was significantly lower in the subgroup with LVOT‐AR >17% compared with the LVOT‐AR ≤17% subgroup ( P =0.03) (Figure ). Comparison of DD and Videodensitometry With CMR The (inverse) correlation between DD and CMR‐RF was −0.29 ( P =0.04) (Figure ) and the correlation between LVOT‐AR and CMR‐RF was 0.52 ( P <0.001) (Figure ). Isolated use of the DD and LVOT‐AR resulted in similar predictive values for relevant PVR (AUC DD: 0.82 [95% CI, 0.69–0.95]; AUC LVOT‐AR: 0.80 [95% CI, 0.62–0.99]). The AUC of PVR on predischarge TTE versus relevant CMR‐assessed PVR (i.e., CMR‐RF >20%) was 0.83 (95% CI, 0.72–0.95). Concordance between DD ≤32 mm Hg and CMR‐RF >20% was 76.5%, whereas concordance between LVOT‐AR >17% and CMR‐RF >20% was 82.3%. PPV and NPV of DD for relevant PVR were 40% and 91.7%, respectively (Table ). PPV and NPV for LVOT‐AR were 50% and 88.4%, respectively. Combination of DD and Videodensitometry in the Assessment of PVR The combination of both modalities yielded an AUC of 0.90 (95% CI, 0.81–0.99) (Figure ). The NRI was 1.08 (95% CI, 0.48–1.68; P <0.001) and the IDI was 0.15 (95% CI, 0.01–0.29; P =0.03) for the combination of DD and LVOT‐AR compared with DD alone. The NRI and IDI for the combination of DD and LVOT‐AR compared with LVOT‐AR alone were 0.89 (95% CI, 0.28–1.50; P =0.005) and 0.08 (95% CI, −0.02 to 0.18; P =0.12), respectively. Combination of both modalities resulted in a concordance of 86.3%, and PPV and NVP of 75% and 87.2%, respectively. An improved AUC was observed for all hemodynamic indices after combining them with the LVOT‐AR, compared with either the AUC of the hemodynamic index alone or the AUC of the LVOT‐AR alone (Figure , Figure ). 

Baseline characteristics of the 51 patients are presented in Table . Mean age was 80.6±5.2 years and 45.1% of patients were men. Mean Society of Thoracic Surgeons score was 2.50±0.92 and 39.2% of patients were in New York Heart Association function class III or IV. Mean left ventricular ejection fraction was 54.0±9.1%, with a mean aortic valve area and aortic valve mean gradient of 0.77±0.18 cm 2 and 45.5±12.9 mm Hg, respectively. 

PVR Assessment Details on procedural characteristics are provided in Table . Post‐implantation values of the 4 hemodynamic indices were the following: 40±11 mm Hg for DD, 42±13 mm Hg/bpm for heart rate‐adjusted‐DD, 29±10 for ARI, and 0.95±0.52 for ARI ratio. Post‐implantation DD was ≤32 mm Hg in 15 (29.4%) patients. The aortic angiogram was analyzable in 51 of 77 patients (analyzability, 66.2%). The reasons for the non‐analyzability of videodensitometry are provided in Table . Mean LVOT‐AR was 8.2%±7.8%. Videodensitometry categorized 26 (51.0%) cases as none/trace PVR, 17 (33.3%) as mild PVR, and 8 (15.7%) as ≥ moderate PVR. Mean duration between TAVR and CMR was 40±15 days. The average CMR‐RF was 11.7±9.6%, with 9 (17.6%) cases with CMR‐RF >20%. In all of the patients with CMR‐RF >20%, this was related to PVR and not to central aortic regurgitation. There were 5 cases with relevant PVR on CMR but not on LVOT‐AR (details shown in Table ). PVR assessment by TTE during follow‐up was performed on the same day as the CMR assessment, and graded PVR as none/trace in 25 (49.0%) patients, mild in 25 (49.0%) patients, and moderate in 1 (2.0%) patient. 

The (inverse) correlation between DD and LVOT‐AR was −0.36 ( P =0.01) (Figure ). The agreement (i.e., either DD ≤32 mm Hg and LVOT‐AR >17%, or DD >32 mm Hg and LVOT‐AR ≤17%) between DD and LVOT‐AR was 70.6%. Mean DD was significantly lower in the subgroup with LVOT‐AR >17% compared with the LVOT‐AR ≤17% subgroup ( P =0.03) (Figure ). 

CMR The (inverse) correlation between DD and CMR‐RF was −0.29 ( P =0.04) (Figure ) and the correlation between LVOT‐AR and CMR‐RF was 0.52 ( P <0.001) (Figure ). Isolated use of the DD and LVOT‐AR resulted in similar predictive values for relevant PVR (AUC DD: 0.82 [95% CI, 0.69–0.95]; AUC LVOT‐AR: 0.80 [95% CI, 0.62–0.99]). The AUC of PVR on predischarge TTE versus relevant CMR‐assessed PVR (i.e., CMR‐RF >20%) was 0.83 (95% CI, 0.72–0.95). Concordance between DD ≤32 mm Hg and CMR‐RF >20% was 76.5%, whereas concordance between LVOT‐AR >17% and CMR‐RF >20% was 82.3%. PPV and NPV of DD for relevant PVR were 40% and 91.7%, respectively (Table ). PPV and NPV for LVOT‐AR were 50% and 88.4%, respectively. 

PVR The combination of both modalities yielded an AUC of 0.90 (95% CI, 0.81–0.99) (Figure ). The NRI was 1.08 (95% CI, 0.48–1.68; P <0.001) and the IDI was 0.15 (95% CI, 0.01–0.29; P =0.03) for the combination of DD and LVOT‐AR compared with DD alone. The NRI and IDI for the combination of DD and LVOT‐AR compared with LVOT‐AR alone were 0.89 (95% CI, 0.28–1.50; P =0.005) and 0.08 (95% CI, −0.02 to 0.18; P =0.12), respectively. Combination of both modalities resulted in a concordance of 86.3%, and PPV and NVP of 75% and 87.2%, respectively. An improved AUC was observed for all hemodynamic indices after combining them with the LVOT‐AR, compared with either the AUC of the hemodynamic index alone or the AUC of the LVOT‐AR alone (Figure , Figure ). 

The aims of this APPOSE substudy were to (1) assess the correlation between the DD and videodensitometry, (2) assess the predictive value of the isolated use of DD versus videodensitometry for the incidence of relevant PVR after TAVR, and (3) determine the additive value of combining the DD and videodensitometry for the prediction of relevant PVR as quantified by gold‐standard CMR. The key findings can be summarized as follows. First, the correlation between DD and videodensitometry was significant but weak (correlation coefficient, −0.36). Second, DD and videodensitometry yielded an equal and high predictive value for relevant PVR as assessed with CMR (AUCs 0.82 and 0.80, respectively). Third, the combination of DD and videodensitometry yielded a higher AUC, NRI, IDI, concordance, and PPV for relevant PVR than the isolated use of the DD or videodensitometry. Taken together, these results highlight the potential of DD and videodensitometry for objective and accurate grading of PVR after TAVR. Although the incidence of PVR is decreasing with newer‐generation TAVR devices and enhanced operator skills, the risk of PVR is still considered an important shortcoming of TAVR. With the increasing evidence that mild to moderate or even only mild PVR is associated with adverse outcomes, in terms of both morbidity and mortality, every effort should be made to reduce the degree of PVR. , Accurate grading of PVR is therefore of paramount importance, especially since various countermeasures are periprocedurally available to reduce PVR. Multiple imaging modalities, such as TTE and angiography, are being used for the assessment of PVR after TAVR. TTE is widely available, inexpensive, and easy to use. However, accurate assessment of PVR by TTE can be challenging due to poor acoustic windows (e.g., due to obesity, chronic obstructive pulmonary disease, or acoustic shadowing of the TAVR stent frame) and multiple and eccentric jets, potentially underestimating the degree of PVR as compared with CMR. , , With the widely adopted minimalist TAVR approach, which uses only local anesthesia and minimal sedation, the use of transesophageal echocardiography for intraprocedural PVR assessment is becoming infeasible for most patients. Traditional angiographic assessment using the visual Sellers' method is widely available, but lacks diagnostic accuracy in quantifying PVR. , CMR is considered an accurate and reproducible technique in the assessment of PVR and is acknowledged as the gold standard for measurements of left ventricular volume, mass, and ejection fraction. , The accuracy of CMR is less influenced by the number and eccentricity of paravalvular leaks than echocardiography. However, CMR does not permit intraprocedural assessment of PVR. Transvalvular hemodynamic indices are readily available and can be performed at various moments during TAVR. These hemodynamic indices have previously been shown to be of prognostic value for post‐TAVR survival. It was demonstrated that DD ≤18 mm Hg, heart rate‐adjusted‐DD <25 mm Hg/bpm, ARI <25, and ARI ratio <0.6 were all independently associated with mortality after TAVR. In addition, ARI ratio <0.6 appeared to be the strongest predictor of 1‐year death after TAVR. Also, these hemodynamic indices have been assessed for their predictive value for relevant PVR. We previously showed that DD had the strongest correlation with CMR‐RF and the highest predictive value for relevant PVR. Alternatively, quantitative videodensitometry has emerged as a well‐feasible and highly reproducible method in the assessment of PVR after TAVR, which can be used both online and offline. , Videodensitometry has been validated in vivo and in vitro, and has robust outcome data to support its prognostic value. In a previous study by Abdel‐Wahab et al., a substantial correlation ( r =0.78) was found between quantitative assessment of PVR using CMR and videodensitometry. In our study, we also found a significant but somewhat weaker correlation between both modalities ( r =0.52). This discrepancy may be explained by the differences in type of TAVR device, CMR postprocessing software, and sample size. The average LVOT‐AR of 8.2% in our cohort is well comparable with those described for other TAVR platforms. , , To the best of our knowledge, this is the first study directly comparing hemodynamic indices with videodensitometry for the assessment of PVR after TAVR. In our study, we found a significant but rather weak ( r =−0.36) correlation between DD and videodensitometry. This weak intermodality correlation and the high predictive values of both the DD and videodensitometry for relevant PVR suggest an important role for complementary use of these modalities. The predictive value for relevant PVR increased (i.e., from AUC 0.80 to AUC 0.90) after combination of both techniques, and the NRI and IDI indicated a significant improvement of the predictive value after combining both modalities. We found a slight increase in the concordance from 76.5% (DD alone) and 82.3% (videodensitometry alone) to 86.3% after combining DD with videodensitometry. In addition, we found a strong increase in the PPV from 40% (DD alone) and 50% (videodensitometry alone) to 75% after combining both modalities. The combination of both modalities was associated with only a modest decrease in the NPV (87.2%) compared with the NPVs of the individual modalities (91.7% for DD, 88.4% for videodensitometry). Future Perspectives The number of TAVR procedures is annually increasing. With the expanded indications to also low‐risk patients, and potentially asymptomatic patients and patients with moderate aortic stenosis, the need for accurately quantifying PVR is undisputable. Hemodynamic indices and videodensitometry are 2 useful techniques that individually, but more importantly synergistically, can aid the operator in periprocedural decision making. Future studies should address the feasibility of the combined use of these modalities. Limitations This study has some limitations. First, the sample size was limited, partly due to a number of patients without analyzable videodensitometry. However, with the implementation of acquisition protocols with computed tomographic guidance to optimize the angiographic projection, the analyzability of videodensitometry substantially increases to >95%. , Optimization of the computed tomography–guided angiographic projection includes avoidance of overlap between the contrast‐filled descending aorta with the LVOT (region of interest) and aortic root (reference area). In addition, the analyzable and nonanalyzable patients have similar characteristics and CMR‐RF as shown in Table . Second, the time difference between angiography (used for videodensitometry) and CMR might have contributed to the difference in PVR quantification between the imaging modalities. Third, this study was solely performed with the Abbott Portico valve, precluding the direct translation of these results to other types of TAVR devices. 

The number of TAVR procedures is annually increasing. With the expanded indications to also low‐risk patients, and potentially asymptomatic patients and patients with moderate aortic stenosis, the need for accurately quantifying PVR is undisputable. Hemodynamic indices and videodensitometry are 2 useful techniques that individually, but more importantly synergistically, can aid the operator in periprocedural decision making. Future studies should address the feasibility of the combined use of these modalities. 

This study has some limitations. First, the sample size was limited, partly due to a number of patients without analyzable videodensitometry. However, with the implementation of acquisition protocols with computed tomographic guidance to optimize the angiographic projection, the analyzability of videodensitometry substantially increases to >95%. , Optimization of the computed tomography–guided angiographic projection includes avoidance of overlap between the contrast‐filled descending aorta with the LVOT (region of interest) and aortic root (reference area). In addition, the analyzable and nonanalyzable patients have similar characteristics and CMR‐RF as shown in Table . Second, the time difference between angiography (used for videodensitometry) and CMR might have contributed to the difference in PVR quantification between the imaging modalities. Third, this study was solely performed with the Abbott Portico valve, precluding the direct translation of these results to other types of TAVR devices. 

DD and videodensitometry are both accurate and feasible modalities for the intraprocedural assessment of PVR after TAVR. The combination of both techniques increases the predictive value for relevant PVR after TAVR. 

The APPOSE trial was funded by a research grant from Abbott Laboratories (grant number 3810455). Abbott had no role in the design and conduct of the trial; in the enrollment of participants; in the collection, analysis, and interpretation of the data; in the preparation, review, or approval of the manuscript; or in the decision to submit the manuscript for publication. 

Dr van Wely has been a proctor and consultant for Abbott Vascular. Dr Heijmen has been a consultant for Medtronic. Dr Serruys reports personal fees from SMT, Philips/Volcano, Xeltis, Novartis, and Meril Life. Dr Soliman reports institutional research grants, including several industry‐sponsored Core Laboratory activities, with no conflict related to the submitted work. Dr van Royen has received research funding from Abbott, Philips, Medtronic, and Biotronik; has served as a consultant for RainMed, Castor, and Medtronic; and received speaker fees from Abbott and Bayer. The remaining authors have no disclosures to report. 

Tables S1–S3 Figure S1 

