Vinnie Bapat

Factors influencing left ventricular outflow tract obstruction following a mitral valve-in-valve or valve-in-ring procedure, part 1

To determine the factors influencing left ventricular outflow tract (LVOT) area reduction after a mitral valve‐in‐valve (VIV) or a valve‐in‐ring (VIR) procedure.

Transaortic Transcatheter Aortic Valve Implantation: Step-by-Step Guide.

Transcatheter aortic valve implantation (TAVI) is currently used to treat high-risk and inoperable patients with aortic stenosis. The established routes of access are retrograde transfemoral (TF) and antegrade transapical (TA). Transubclavian and transaortic (TAo) routes have been described. We have performed TAo-TAVI with the Edwards Sapien prosthesis (Edwards Lifesciences, Irvine, CA) with the Ascendra I delivery system. From 2010 we have used the Sapien XT prosthesis with the Ascendra II delivery system. In this article we describe in detail the technical aspects of performing TAo TAVI.

Fluoroscopic guide to an ideal implant position for Sapien XT and CoreValve during a valve-in-valve procedure.

OBJECTIVES This study sought to provide a guide to the fluoroscopic appearances of various valve-in-valve (VIV) combinations by deploying a transcatheter heart valve (THV) within a degenerated surgical heart valve (SHV) in an ideal position. BACKGROUND VIV procedures are being increasingly performed with substantial experience acquired in treating degenerated SHV in the aortic position with Sapien/Sapien XT (Edwards Lifesciences Ltd., Irvine, California) and CoreValve/Evolute (Medtronic Inc., Minneapolis, Minnesota) valves. Although less invasive than conventional surgery, securing the THV in an optimal position within the SHV determines the success of this novel treatment. METHODS For VIV implantation, we selected appropriate Sapien XT and CoreValve/Evolute sizes depending on the internal diameter of the SHV. Implantation was performed in vitro. In case of the Sapien XT valve, it was deployed 4 to 5 mm below the sewing ring of the SHV, whereas the CoreValve/Evolute was deployed 5 mm below the level of the sewing ring. Photographs and fluoroscopic images of the various VIV combinations were obtained in side profile to study the ideal position and end-on profile to study the circularity of the THV. RESULTS Fluoroscopic images obtained in side profile highlighted the differences in various VIV combinations, as all SHV are unique in their fluoroscopic appearances. Also, all THV implants in various VIV combinations achieved a nearly circular shape. CONCLUSIONS To achieve an optimal result when considering VIV, it is important to be familiar with the structure and fluoroscopic appearances of the failed SHV, the THV used, and their combination.

Transcatheter aortic valve implantation for treatment of failing homograft with preexisting mechanical mitral prosthesis.

Transcatheter aortic valve implantation is increasingly used to treat bioprosthetic degeneration. Valve‐in‐valve technique has been performed successfully to treat homograft, stentless, and stented bioprosthetic dysfunction. The presence of a prosthesis in the mitral position can make the transcatheter aortic valve implantation procedure challenging due to proximity of the mitral and aortic annuli. We describe the case of a 66‐year‐old who underwent the first successful implantation of Edwards Sapien device in a failing homograft in the presence of a mechanical mitral valve prosthesis.

Severe intraprosthetic regurgitation by immobile leaflet after transcatheter aortic valve implantation.

Dear Editor We read with interest the case report by Al-Attar et al. [1] regarding the fatal complication of severe intravalvular leak due to an immobile cusp following trans-apical TAVI with 23 mm Edwards-SAPIEN valve. We congratulate the team for sharing their complication which is under reported and at times overlooked. The patient developed rapid severe left ventricular dysfunction despite all attempts to correct the situation failed (including positioning of a second valve-in-valve and the use of femorofemoral Extracorporeal membrane oxygenation). We also noted the editorial comment regarding the possibility of damage to the valve leaflets while hooking the leaflet on the stent during the crimping phase as a possible origin of the irreversible immobility. At our institute, over the past three years, we have implanted over 230 Edward-SAPIEN and XT valves [2]. We have also noted the onset of this complication in two patients. The immobility of the stent valve leaflet was transient and due to inadequate balloon inflation of the valve in the patients. Once the valve is balloon expanded again, the stent fully deployed allowing the valve leaflets to function properly. We do not believe that crimping is the cause but as described by the authors it must be an irregular expansion on the stent, which leads to aortic regurgitation. We think noncircular expansion is the major mechanism, as implanted stented surgical valves are circular and always function well unless there is distortion of the stent during implantation. Also, aortic regurgitation is observed after stentless valve implantation when there is distortion of the stentless valve anatomy, i.e. loss of circular shape. Hence they need expertise and experience to achieve best results [3]. Once implanted the valve opens due to ventricular contraction and closes due to the eddy currents generated [4]. If with adequate pressure head the leaflet function is not satisfactory, then we agree that the only option is implanting another stent with or without circulatory support depending on the degree of regurgitation and haemodynamic stability. In our centre, we performed a case where valve-in-valve implantation was necessary to achieve successful outcome after such a complication. In our experience, we believe it is unlikely that crimping is a cause for this complication. The published literature suggests complications related to the valve mechanism for the Edwards SAPIEN valve, and valve-in-valve implantation or implantation of a second valve being 2.6% [5]. Bearing these observations in mind, we too support the editorial reflections in strongly advocating cardiovascular surgical team present jointly for all TAVI cases, with the facility to go on cardiopulmonary bypass expediently. In our experience the procedure is performed under general anaesthesia with continuous transoesophageal echocardiography. This allows excellent haemodynamic control and visualization of the valve with early identification of the mechanism of valve dysfunction and treatment. In order to expand the application of this technology to moderate risk populations in the near future, we need to ensure that TAVI is performed in highly controlled environment. There needs to be anaesthetic, echocardiographic and surgical team support to lower complications, reduce mortality and achieve excellent outcomes.

Transaortic transcatheter aortic valve implantation using the Edwards Sapien valve

Transcatheter aortic valve implantation using Edwards Sapien Valve can be carried out through the ascending aorta. In the majority of patients, the ascending aorta is approached through a partial upper J-sternotomy. The sternotomy extends into the right second or third right intercostal space. The pericardium is opened in midline and the top of the ascending aorta is exposed. Two purse-string sutures are then placed on the ascending aorta and Sapien valve implantation is carried out using the Ascendra delivery system with the valve mounted in a reverse fashion to that of a transapical approach. Owing to the familiarity of the surgeons with exposing the aorta and placing purse-strings for cannulation, this procedure is within the comfort zone of surgeons compared with the transapical approach. Advantages, contra--indications, surgical technique and results are also discussed.

Successful treatment of failing biological prosthesis because of “Stent creep” with valve‐in‐valve transcatheter aortic valve implantation

Stent creep is an uncommon mode of structural deterioration of bioprosthetic heart valves defined by a permanent inward deflection of the stent posts. This may occur because of valve over‐sizing and leads to intrinsic valve stenosis. It has been described in older generation of bioprosthesis and was thought not to occur in modern devices.

Challenges in Valve-in-Valve Therapy for Aortic Valves

Transcatheter aortic valve replacement has recently established itself as the treatment of choice in inoperable and high-risk patients with aortic stenosis. Experience in this field has led to its usage for novel indications such as its use in the treatment of a degenerative biological surgical heart valves and is referred to as valve-in-valve (VIV). Early experience demonstrates that the procedure is not without risks. High residual gradients, coronary occlusion, embolization, and thrombosis have been reported. We aim to discuss relevant features of the different surgical and transcatheter devices and discuss the optimal strategy to avoid these complications after a VIV procedure.

Rebuttal: Fluoroscopic characterization of surgical bioprosthetic heart valves.

We appreciate and acknowledge the queries raised by Dr. Kiefer and colleagues regarding correct identification of the various models of the pericardial stented valves manufactured by Edwards Lifesciences (Irvine, CA) [1]. Our publication Bapat et al. was the first publication to compile actual and fluoroscopic appearance of various surgical heart valves (SHV) as there was paucity of the data on this subject [2]. Carpentier Edwards Pericardial aortic SHV has been manufactured and implanted for last three decades. It has undergone some major and minor modifications to accommodate surgical needs. Further, certain models were available only in USA and few only in mainland Europe. For example, Carpentier-Edwards Perimount (Model 2700) is sold only in USA. We acknowledge that we have labelled CarpentierEdwards Magna Ease model as Carpentier-Edwards Magna in Figs. 2B and 3B but point to the fact that we have correctly labelled Carpentier-Edwards Perimount model (either 2725 or 2800) in Figs. 2A, 3A, and 5B of the manuscript and it is not to be confused with Carpentier-Edwards Magna model 3000 although they appear similar under fluoroscopy [2]. To address and answer this confusion, we have compiled images and fluoroscopic appearance of all four models to highlights the similarities and subtle differences in their appearances (Fig. 1). It should be noted that Carpentier-Edwards Perimount (Model 2725/2800) (Fig. 1A) and Carpentier-Edwards Perimount Magna (Model 3000) (Fig. 1C) look similar under fluoroscopy. Their dimensions relevant to the valve-in-valve procedure are, however, similar [2,3] but ideal placement of a THV within them may differ. It should be noted that, Carpentier-Edwards Perimount 2725/2800 is an intra-annular model and Carpentier-Edwards Perimount Magna 3000 is a supra-annular model. The essential difference between them is the level of the sewing ring in relation to the stent frame (Fig. 1A, C). In the former, the sewing ring is approximately 15% higher than the base of the stent frame (Fig. 1A) and in the later the sewing ring and the base of the stent frame is at the same level (Fig. 1C). This is important for correct placement of the implant as the sewing ring is the ‘neo-annulus’ of the SHV [4,5]. Hence in the Carpentier-Edwards Perimount (Model 2725/2800), placement of Sapien XT or CoreValve in line with the basal band (Fig. 2A) will ensure secure placement and avoid a very low placement but in Carpentier-Edwards Perimount Magna (Model 3000), the transcatheter valves must be placed few mm below the visible basal band (Fig. 2C) as demonstrated by Kiefer et al in the Fig. 3B. We aim to include all four models, their fluoroscopic appearance and recommendation for ideal deployment in the next update of the VIV App and we thank Dr. Kiefer and colleagues for highlighting this issue.