ABC | Volume 111, Nº2, August 2018

Original Article Arq Bras Cardiol. 2018; 111(2):193-202 Miyazaki et al Videodensitometry assessment of AR to guide TAVI After BPD, VD-AR > 17% was still seen in 31% of patients. Based on current available data, for patients with residual AR (VD-AR > 17%), additional measures should be taken. We found higher mortality in patients with VD-AR > 17% compared to patients with VD-AR ≤ 17% during the follow‑up (34% vs. 19%). Although the difference in mortality was not significant (log rank p = 0.273) in this small population with BPD, a tendency for high mortality was previously reported in patients with VD-AR > 17% in a large population. 14,16 VD-AR deteriorated numerically in 11 patients, and this deterioration was significant in 3. This comes in agreement with previous studies which also reported AR deterioration in a small proportion of patients after BPD, 8 and could be due to prosthetic overexpansion with secondary leaflet maladaptation and transvalvular regurgitation. 23 Serial changes of VD-AR showed predominantly improvement of AR. A reduction of the regurgitation by BPD was reported in 68%-91% in the literature. 8,24 The mechanisms of regurgitation after implantation of THV are multifactorial as, for example, calcification of the native aortic annulus and left ventricular outflow tract (LVOT) and cover index are well known predicting factors of regurgitation after implantation of a THV. 19,26-34 To make a decision whether BPD is needed or not and to judge its efficiency, repeated injections of large doses of contrast medium would be needed. Contrast medium volume used in this population was 150[131-209] ml/procedure. In the setting of TAVI, peri-procedural acute kidney injury (AKI) develops in 12% to 57% of cases and portends a significant increase in early and late mortality. 34,35 The mechanisms of AKI following TAVI are multifactorial, and the role of the contrast medium volume is controversial. 36 However, there is some evidence suggesting that a larger contrast volume is related to an increased risk of AKI after TAVI. 34,37 Taking into account the important role of aortography in the minimalist TAVI era, repeated aortograms cannot be avoided. However, the possibility of reducing contrast medium is reported using a diastolic phase-synchronized injection of only 8 ml of contrast medium in an in-vitro setting. 12 This technique could enable the reduction of the total amount of contrast medium during the procedure. Limitations After implantation of the THV, the guidewire is frequently left in the left ventricle and may produce artificial transvalvular regurgitation. 38 However, the effect of the guidewire on AR during TAVI is variable according to the weight of the wire. Most operators decide whether to perform BPD with or without a guidewire in LV by using echocardiography and aortography. Indeed, in the present study, VD-AR before BPD was analysed either with (n = 49) or without (n = 12) the guidewire being left in the left ventricle. One limitation of our study is the absence of data on aortic regurgitation index, thus lacking the possibility of comparing this to our method. Limitations of VD-AR assessment are its feasibility. The current report is a retrospective study so that the acquisition of aortography was not dedicated for VD-AR assessment. In order to perform videodensitometric assessment appropriately, the acquisition of aortography should be done without overlapping ROI with contrast filled ascending/descending aorta. Recently, Teng et al. 39 reported how to plan an overlap free projection for VD-AR assessment. 39 A dedicated acquisition protocol would achieve a high feasibility of assessment. We tried to overcome this limitation by choosing the cases that did had an adequate acquisition of images, lowering our sample size. However, a prospective clinical study is needed to confirm this hypothetical assumption. So far, CAAS-A-valve software is available as an offline system. Currently, attempts are being made to allow online assessment. 40 In the near future, online system will probably foster the VD-AR as guidance for TAVI. In this registry, no echocardiographic parameters recorded were reported after THV deployment but before BPD. The information of calcification of the native aortic valve, annulus and LVOT from computed tomography were not available. Conclusion VD-AR after THV implantation enables the operator to assess quantitatively regurgitation, to rationalise BPD and to assess its efficacy. Acknowledgements We thank Jean-Paul Aben for preparing the supportingmovie. Author contributions Conception and design of the research: Miyazaki Y, Modolo R, Abdelghani M, Tateishi H, Cavalcante R, Collet C, Asano T, Tenekecioglu E, Mangione JA, Abizaid A, Soliman OII, Onuma Y, Serruys PW, Lemos PA, Brito Jr. FS; Acquisition of data: Miyazaki Y, Modolo R, Abdelghani M, Tateishi H, Cavalcante R, Katagiri Y, Sarmento-Leite R, Mangione JA, Abizaid A, Soliman OII, Onuma Y, Serruys PW, Lemos PA, Brito Jr. FS; Analysis and interpretation of the data: Miyazaki Y, Modolo R, Abdelghani M, Tateishi H, Cavalcante R, Collet C, Asano T, Katagiri Y, Tenekecioglu E, Mangione JA, Abizaid A, Soliman OII, Onuma Y, Serruys PW; Statistical analysis: Miyazaki Y, Modolo R, Abdelghani M, Cavalcante R, Collet C, Asano T, Katagiri Y, Mangione JA, Abizaid A, Soliman OII, Serruys PW, Brito Jr. FS; Writing of the manuscript: Miyazaki Y, Modolo R, Abdelghani M, Asano T, Mangione JA, Abizaid A, Serruys PW; Critical revision of the manuscript for intellectual content: Miyazaki Y, Modolo R, Abdelghani M, Tateishi H, Cavalcante R, Collet C, Asano T, Katagiri Y, Tenekecioglu E, Sarmento-Leite R, Mangione JA, Soliman OII, Onuma Y, Serruys PW, Lemos PA, Brito Jr. FS. Potential Conflict of Interest Rogério Sarmento-Leite, José A. Mangione, and Fabio S. de Brito Jr are proctors for Medtronic and Edwards Lifesciences. Pedro A. Lemos is a proctor for Edwards Lifesciences and Boston Scientific. All other authors have no relevant conflicts of interest to declare. Sources of Funding There were no external funding sources for this study. Study Association This article is part of the thesis of Doctoral submitted by Yosuke Miyazaki, from Erasmus University. 200