Quantitative aortography for assessing aortic regurgitation after transcatheter aortic valve implantation: results of the multicentre ASSESS-REGURGE Registry.

AIMS: Quantitative aortography using videodensitometry is a valuable tool for quantifying paravalvular regurgitation after TAVI, especially in the minimalist approach - without general anaesthesia. However, retrospective assessment of aortograms showed moderate feasibility of assessment. We sought to determine the prospective feasibility of quantitative aortography after a protocol of acquisition. METHODS AND RESULTS: This was a multicentre registry in Japan, Canada, the Netherlands and Germany including consecutive patients with Heart Team indication to undergo TAVI over a median period of 12 months. Operators performed final aortograms according to a pre-planned projection (either by CT or visually - Teng's rule). An independent core laboratory (Cardialysis) analysed all images for feasibility and for regurgitation assessment. From the four centres included in the present analysis, a total of 354 patients underwent TAVI following the acquisition protocol and all the aortograms were analysed by the core lab. The analyses were feasible in 95.5% (95% confidence interval [CI]: 93.2% to 97.5%) of the cases. This rate of analysable assessment was significantly higher than the feasibility in previous validation studies, such as in the RESPOND population (95.5% vs. 57.5%, p<0.0001). No differences were observed among different planning strategies (CT 96.5% vs. Teng's rule 93%, p=0.159; or Circle 98.5% vs. 3mensio 95.8% vs. Teng's rule 93%, p=0.247). CONCLUSIONS: ASSESS-REGURGE showed a high feasibility of assessment of regurgitation with quantitative aortography with protocoled acquisition. This may be of great importance for quantifying regurgitation in TAVI procedures (optimisation, guidance of post-dilatation), and in future clinical trials, in order to address sealing features of novel devices for TAVI objectively. ClinicalTrials.gov Identifier: NCT03644784.

HDR monotherapy for prostate cancer: a simulation study to determine the effect of catheter displacement on target coverage and normal tissue irradiation.

PURPOSE: The aim of this study was to systematically analyse the effect of catheter displacements both on target coverage and normal tissue irradiation in fractionated high dose rate (HDR) prostate brachytherapy, using a simulation study, and to define tolerances for catheter displacement ensuring that both target coverage and normal tissue doses remain clinically acceptable. Besides the effect of total implant displacement, also displacements of catheters belonging to selected template rows only were evaluated in terms of target coverage and normal tissue dose, in order to analyse the change in dose distribution as a function of catheter dwell weight and catheter location. MATERIAL AND METHODS: Five representative implant geometries, with 17 catheters each, were selected. The clinical treatment plan was compared to treatment plans in which an entire implant displacement in caudal direction over 3, 5, 7 and 10 mm was simulated. Besides, treatment plans were simulated considering a displacement of either the central, most ventral or most dorsal catheter rows only, over 5 mm caudally. RESULTS: Due to displacement of the entire implant the target coverage drops below the tolerance of 93% for all displacements studied. The effect of displacement of the entire implant on organs at risk strongly depended on the patient anatomy; e.g., for 80% of the implant geometries the V(80) of the rectum exceeded its tolerance for all displacements. The effect of displacement of catheters belonging to selected template rows depended strongly on the relative weight of each catheter row when considering the target coverage and on its location when considering the dose in the organs at risk. CONCLUSION: This study supports the need for a check of the catheter locations before each fraction and correction of deviations of the catheter position exceeding 3mm.