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Iterative Learning of Transcatheter Mitral Valve Replacement in Mitral Valve Annulus Calcification: Management and Prevention of Transcatheter Mitral Valve Replacement Dislocation
Iterative Learning of Transcatheter Mitral Valve Replacement in Mitral Valve Annulus Calcification: Management and Prevention of Transcatheter Mitral Valve Replacement Dislocation Michal Hulman, MD, PhD, Martin Bena, MD, Panagiotis Artemiou, MD, PhD, Ivo Gasparovic, MD, Vladan Hudec, MD, Ronak Rajani, MD, and Vinayak Bapat, MD Clinic of Cardiac Surgery, National Institute of Cardiovascular Diseases, Medical Faculty of the Slovak Health University, Bratislava, Slovakia; and Department of Cardiology and Cardiothoracic Surgery, Guy’s and St. Thomas’ Hospital NHS Foundation Trust, London, United Kingdom
Transcatheter mitral valve replacement using balloonexpandable valves is an emerging technique for the treatment of patients with significant mitral regurgitation who have been judged to be inoperable owing to significant mitral valve annulus calcification. Although initial reports have been promising, there remains a lack of consensus as to how to plan for transcatheter mitral valve replacement deployment in terms of appropriateness, sizing, and positioning to mitigate the risks of valve displacement and paravalvular regurgitation. We describe two cases of transcatheter mitral valve replacement in patients with significant mitral valve annulus calcification. The first was complicated by valve displacement into the left atrium, which was successfully managed by surgical redeployment and fixation. The second case was thereafter performed successfully using iterative learning and the application of specific preprocedural planning techniques acquired from a root cause analysis of the first case. We describe our experience with both cases and the specific planning principles required to prevent transcatheter mitral valve replacement displacement in patients with mitral valve annulus calcification. (Ann Thorac Surg 2016;102:e287–90) Ó 2016 by The Society of Thoracic Surgeons
P
atients with severe mitral valve disease and concomitant significant mitral valve annulus calcification (MAC) pose a significant challenge for surgical mitral valve replacement or repair [1]. Without surgical debridement, there is a risk of embolization, ventricular rupture, and significant paravalvular leaks from poor coaptation of the valve to the rigid annulus. With surgical debridement, although better coaptation of the prosthetic
Accepted for publication Feb 16, 2016. Address correspondence to Dr Artemiou, National Institute of Cardiovascular Diseases, Pod krasnou horkou 1, 83101, Bratislava, Slovakia; email: [email protected].
Ó 2016 by The Society of Thoracic Surgeons Published by Elsevier
valve to the annulus may be achieved, it comes at the risk of atrioventricular rupture with its associated high mortality. This dilemma has generated considerable interest in the application of less-invasive strategies to treat this unique condition. Provisional reports indicate that transcatheter mitral valve replacement (TMVR) using a balloonexpandable transcatheter aortic valve through a transatrial [2], transapical [3], and completely percutaneous approach [4] may represent viable treatment options. Despite initial success with these techniques, there is a lack of consensus in how to size and plan for these procedures and how to avoid valve displacement toward the left atrium. In the current report we describe two cases of TMVR using the Sapien XT and S3 transcatheter balloonexpandable aortic valves, respectively (Edwards Lifesciences, Irvine, CA). The first case was complicated by valve displacement toward the left atrium, which was successfully managed. The second case was performed successfully without displacement after incorporation of specific preprocedural planning techniques acquired from the first case.
Case Reports Patient 1 A 39-year-old woman with a history of rheumatic heart disease presented to our institute with worsening exertional dyspnea (New York Heart Association functional class II or III). Echocardiography confirmed the presence of severe aortic and mitral stenosis along with heavy calcification of the aortic and mitral valve annuli and aortomitral continuity. Although left ventricular diastolic function was preserved, there was evidence of diastolic dysfunction. The patient underwent invasive coronary angiography, which demonstrated normal coronary arteries, and a cardiac computed tomographic (CT) scan. The CT scan confirmed the presence of heavy MAC. After a surgical review, the patient was judged to represent a high-risk surgical candidate, and a conservative management or nonsurgical strategy was recommended. After a multidisciplinary heart team discussion, we elected to perform a simultaneous transcatheter aortic and mitral valve replacement procedure. The procedure was done under the guidance of transesophageal echocardiography (TEE) with the use of cardiopulmonary bypass (CPB), peripheral cannulation of the femoral artery and vein, and entry through the transapical approach, according to the recommendations [5]. An Edwards Sapiens S3 23-mm valve was implanted in the aortic position and a Sapiens XT 26-mm valve was implanted in the mitral position. Although the procedure was performed successfully and without periprocedural event, during hospitalization the clinical condition of the patient deteriorated. Further echocardiography showed Dr Rajani discloses a financial relationship with Edwards Lifesciences; Dr Bapat with Edwards Lifesciences, Boston Scientific, and Sorin.
0003-4975/$36.00 http://dx.doi.org/10.1016/j.athoracsur.2016.02.061
e288
CASE REPORT HULMAN ET AL TMVR IN MAC, VALVE DISLOCATION
new severe mitral regurgitation with a dislocation of the mitral prosthetic valve from the annulus toward the left atrium (Fig 1A). At day 17 the patient underwent a redo procedure, which was done through a left transatrial approach with median sternotomy and the use of CPB, bicaval cannulation, and cardioplegic arrest. This confirmed the etiology of the severe mitral regurgitation to be dislocation of the prosthetic mitral valve toward the left atrium and trapping of the anterior mitral valve leaflet below the prosthesis. After applying traction to the interventricular septum, the valve was completely released from the annulus. The valve was manually collapsed and was repositioned back into the native mitral valve annulus before being deployed with the use of an expandable balloon. To prevent repeat dislocation, the valve was additionally fixed with three sutures between the valve stent frame and the anterior mitral valve leaflet annular site. The postoperative echocardiogram showed normal positioning and function of the aortic prosthetic valve and a residual moderate paravalvular leak of the prosthetic mitral valve (Fig 1B). After 2 weeks of further hospitalization, the patient was successfully
Ann Thorac Surg 2016;102:e287–90
discharged home. At 5 months’ follow-up, the patient was in New York Heart Association functional class I or II with echocardiography showing no deterioration in the degree of paravalvular regurgitation.
Patient 2 A 69-year-old man with a history of aortic and mitral valve disease presented to our institute with worsening exertional dyspnea (New York Heart Association functional class III). Echocardiography showed severe aortic valve stenosis, moderate mitral valve regurgitation, and mild tricuspid regurgitation along with heavy calcification of the aortic and mitral valve annuli and the aortomitral continuity. The diagnostic coronary angiography showed obstructed coronary arteries. The patient underwent a surgical review and was accepted for aortic and mitral valve replacement, tricuspid valve repair, and a maze procedure. At surgery, aortic valve replacement was performed with a Sorin Perceval S bioprosthesis valve (Sorin Group, Mirandola, Italy), the tricuspid valve was repaired with an Edwards Physio ring, 34 mm, and the maze procedure was performed with left side epicardial cryoablation. The procedure on the mitral valve, however, was abandoned owing to the operative finding of the heavy MAC. After the operation, cardiac CT was performed to evaluate the degree of MAC and to facilitate sizing of the annulus. Two weeks later, the patient underwent a transapical transcatheter mitral valve implantation of an Edwards Sapiens S3 29-mm valve without complication (Fig 2). In contrast to the first case, we elected to use three key strategies to avoid a repetition of valve dislocation. The first was to use a larger valve size (oversizing) than indicated by the CT and echocardiographic measurements. The second was to position the valve deeper in the annular plane (60% ventricular to 40% mitral annular plane). The third was to perform overdilatation of the expandable valve by 3 mL more than the manufacturer’s recommendations at the ventricular part of the prosthetic valve. The postoperative echocardiogram and CT showed a good position and functioning of the aortic and mitral valves. On day 9, the patient was discharged home in good condition (Fig 3).
Comment
Fig 1. (A) Transesophageal echocardiograph showing the dislocated valve toward the left atrium (LA, open arrow) and the transcatheter aortic valve implantation in situ (closed arrow). (B) Cardiac computed tomography scan showing the final positions of both valves after the redeployment of the mitral valve. (AA ¼ ascending aorta; Ao ¼ aortic root; LV ¼ left ventricle.)
In the current report we describe two cases of TMVR in patients with severe MAC. The first case was complicated by dislocation of the TMVR toward the left atrium. After conducting a root cause analysis, we identified three contributory factors to the occurrence. These were used for evaluating the second case, which was thereafter performed without periprocedural complication or subsequent valve dislocation. Owing to the difficulties that MAC poses for surgical intervention on the mitral valve, there has been a necessary development of alternative strategies to treat patients with this condition. Perhaps the technique that has gained the most interest is TMVR using balloon-expandable
Ann Thorac Surg 2016;102:e287–90
CASE REPORT HULMAN ET AL TMVR IN MAC, VALVE DISLOCATION
e289
Fig 2. (A) Preoperative cardiac computed tomography scan showing the Sorin Perceval valve (closed arrow), the tricuspid annular ring, and the heavily calcified mitral annulus (MAC). (B) Transesophageal echocardiography showing the implanted mitral prosthetic valve (open arrow).
valves. Although initial reports have been promising [2–4], concerns still remain about subsequent valve dislocation and the occurrence of significant paravalvular regurgitation. Additionally there remains a lack of consensus as to the approach to use (transapical, transatrial, or completely transcutaneous) and the precise method for sizing of the annulus. It has therefore become imperative to develop registry data on TMVR in MAC to enable the pooling of worldwide experience to optimize patient outcomes and to mitigate complications. We observed in the current report that TMVR with aortic balloon-expandable valves is feasible in patients with significant MAC. Similar to other authors [4, 6] we used the Edwards Sapiens S3 and XT bioprosthesis valves. Other reports exist of other devices also being successfully used. Use of TMVR in MAC was reported by El-Eshmawi and colleagues [7] with the Melody transcatheter pulmonary balloon-expandable valve (transatrial access), Lim and associates [8] with the Lotus valve, and Mellert and coworkers [3] with the DirectFlow valve. As worldwide experience increases, the true incidence of prosthetic mitral valve dislocation and paravalvular regurgitation will become more transparent. Based on our experience, we identified three potential factors that may contribute to both of these complications: 1. Prosthetic valve size. In the second patient we used a 29-mm valve instead of the 26-mm valve that was used in the first patient to avoid this complication. In
Fig 3. (A) Fluoroscopy showing the overdilatation of the ventricular part of the valve and the deeper valve positioning into the left ventricle. (B) Cardiac computed tomography scan showing the position of the implanted prosthetic mitral valve.
our opinion, deployment of the larger valve size (oversizing) reduces the risk for dislocation owing to better anchoring to the native mitral valve annulus. In the absence of a validated standard method for mitral annulus sizing, operators have extrapolated from transcatheter aortic valve replacement experience and used a variety of sizing approaches, including echocardiography, three-dimensional transesophageal echocardiography, cardiac CT, and balloon sizing techniques. We consider cardiac CT to be the optimal method for sizing the mitral valve annulus and recommend multiphase electrocardiograph-gated CT to assess the mitral valve annulus size at various stages of the cardiac cycle before deciding on a specific valve size. 2. Valve positioning in the annular plane. In the second patient, the valve was positioned deeper in the annular plane, with 60% in the ventricular and 40% in the atrial annular plane. In our opinion, the valve has a more stable anchoring with this position, so the risk for valve dislocation is reduced.
e290
CASE REPORT HULMAN ET AL TMVR IN MAC, VALVE DISLOCATION
3. Expandable balloon dilatation. In the first patient the volume that was used for balloon dilatation was according to the manufacturer’s guidelines. In our opinion, an overdilatation of the balloon at the ventricular part of the prosthetic valve provides better stabilization of the prosthetic valve in the native calcified annulus. In the second patient, the balloon was overdilated by 3 mL above the manufacturer’s recommended guidelines. A combination of all three preventive measures will increase the technical success to a comparable level as that of the open transatrial approach [2, 4]. Concerning management of the complication of dislocation, there remains a paucity of data in the literature. In our first patient, the valve was repositioned back in the native mitral annulus using an open transatrial approach by manual collapse and redeployment of the valve with the use of an expandable balloon. It was then fixed with an additional three sutures between the valve stent frame and the annulus. Alternative techniques include surgical extraction of the valve or stabilization of the prosthetic valve in the interatrial septum. Cardiac CT is the preferred modality for the diagnosis of the severity of the MAC, and should have a more liberal use in this process to plan the appropriate procedure, surgical or transcatheter. Alternative techniques are susceptible to grossly underestimating the extent, distribution, and geometry of MAC, which may result in needless and aborted sternotomies as documented in the second case. In the current report we document two different experiences of TMVR in MAC. The first case illustrates the real risk of valve dislocation in patients undergoing
Ann Thorac Surg 2016;102:e287–90
TMVR for MAC. Subsequently we report a second case of uncomplicated TMVR in MAC in which specific strategies were used to ensure an optimal outcome. Finally we show the rare imaging findings of both of these cases.
References 1. Vohra HA, Whistance RN, Bezuska L, Livesey SA. Surgery for non-rheumatic calcific mitral stenosis. J Heart Valve Dis 2011;20:624–5. 2. Wilbring M, Alexiou K, Tugtekin SM, et al. Pushing the limits-further evolutions of transcatheter valve procedures in the mitral position, including valve-in-valve, valve-in-ring and valve-in-native-ring. J Thorac Cardiovasc Surg 2014;147: 210–9. 3. Mellert F, Sinning JM, Werner N, et al. First–in-human transapical mitral valve replacement using the Direct Flow Medical aortic valve prosthesis. Eur Heart J 2015 Aug 14;36(31):2119; Epub 2015 May 20. 4. Puri R, Abdul-Jawad Altisent O, Del-Tingo M, et al. Transcatheter mitral valve implantation for inoperable severely caicified native mitral valve disease: a systematic review. Catheter Cardiovasc Interv 2016;87:540–8. 5. Holmes DR Jr, Mack MJ, Kaul S, et al. 2012 ACCF/AATS/ SCAI/STS Expert consensus document on trancatheter aortic valve replacement. J Am Coll Cardiol 2012;59:1200–54. 6. Lee R, Fukuhara S, George I, Borger MA. Mitral valve replacement with a transcatheter valve in the setting of severe mitral annular calcification. J Thorac Cadiovasc Surg 2016;151: e47–9. 7. El-Eshmawi A, Love B, Bhatt HV, Pawale A, Boateng P, Adams DH. Direct access implantation of a Melody valve in native mitral valve hybrid approach in the presence of extensive mitral annular calcification. Ann Thorac Surg 2015;99:1085. 8. Lim ZY, Boix R, Prendergast B, et al. First reported case of transcatheter mitral valve implantation in mitral annular calcification with a fully repositionable and self-expanding valve. Circ Cardiovasc Interv 2015;8(11):e003031.
Transcatheter mitral valve replacement using balloonexpandable valves is an emerging technique for the treatment of patients with significant mitral regurgitation who have been judged to be inoperable owing to significant mitral valve annulus calcification. Although initial reports have been promising, there remains a lack of consensus as to how to plan for transcatheter mitral valve replacement deployment in terms of appropriateness, sizing, and positioning to mitigate the risks of valve displacement and paravalvular regurgitation. We describe two cases of transcatheter mitral valve replacement in patients with significant mitral valve annulus calcification. The first was complicated by valve displacement into the left atrium, which was successfully managed by surgical redeployment and fixation. The second case was thereafter performed successfully using iterative learning and the application of specific preprocedural planning techniques acquired from a root cause analysis of the first case. We describe our experience with both cases and the specific planning principles required to prevent transcatheter mitral valve replacement displacement in patients with mitral valve annulus calcification. (Ann Thorac Surg 2016;102:e287–90) Ó 2016 by The Society of Thoracic Surgeons
P
atients with severe mitral valve disease and concomitant significant mitral valve annulus calcification (MAC) pose a significant challenge for surgical mitral valve replacement or repair [1]. Without surgical debridement, there is a risk of embolization, ventricular rupture, and significant paravalvular leaks from poor coaptation of the valve to the rigid annulus. With surgical debridement, although better coaptation of the prosthetic
Accepted for publication Feb 16, 2016. Address correspondence to Dr Artemiou, National Institute of Cardiovascular Diseases, Pod krasnou horkou 1, 83101, Bratislava, Slovakia; email: [email protected].
Ó 2016 by The Society of Thoracic Surgeons Published by Elsevier
valve to the annulus may be achieved, it comes at the risk of atrioventricular rupture with its associated high mortality. This dilemma has generated considerable interest in the application of less-invasive strategies to treat this unique condition. Provisional reports indicate that transcatheter mitral valve replacement (TMVR) using a balloonexpandable transcatheter aortic valve through a transatrial [2], transapical [3], and completely percutaneous approach [4] may represent viable treatment options. Despite initial success with these techniques, there is a lack of consensus in how to size and plan for these procedures and how to avoid valve displacement toward the left atrium. In the current report we describe two cases of TMVR using the Sapien XT and S3 transcatheter balloonexpandable aortic valves, respectively (Edwards Lifesciences, Irvine, CA). The first case was complicated by valve displacement toward the left atrium, which was successfully managed. The second case was performed successfully without displacement after incorporation of specific preprocedural planning techniques acquired from the first case.
Case Reports Patient 1 A 39-year-old woman with a history of rheumatic heart disease presented to our institute with worsening exertional dyspnea (New York Heart Association functional class II or III). Echocardiography confirmed the presence of severe aortic and mitral stenosis along with heavy calcification of the aortic and mitral valve annuli and aortomitral continuity. Although left ventricular diastolic function was preserved, there was evidence of diastolic dysfunction. The patient underwent invasive coronary angiography, which demonstrated normal coronary arteries, and a cardiac computed tomographic (CT) scan. The CT scan confirmed the presence of heavy MAC. After a surgical review, the patient was judged to represent a high-risk surgical candidate, and a conservative management or nonsurgical strategy was recommended. After a multidisciplinary heart team discussion, we elected to perform a simultaneous transcatheter aortic and mitral valve replacement procedure. The procedure was done under the guidance of transesophageal echocardiography (TEE) with the use of cardiopulmonary bypass (CPB), peripheral cannulation of the femoral artery and vein, and entry through the transapical approach, according to the recommendations [5]. An Edwards Sapiens S3 23-mm valve was implanted in the aortic position and a Sapiens XT 26-mm valve was implanted in the mitral position. Although the procedure was performed successfully and without periprocedural event, during hospitalization the clinical condition of the patient deteriorated. Further echocardiography showed Dr Rajani discloses a financial relationship with Edwards Lifesciences; Dr Bapat with Edwards Lifesciences, Boston Scientific, and Sorin.
0003-4975/$36.00 http://dx.doi.org/10.1016/j.athoracsur.2016.02.061
e288
CASE REPORT HULMAN ET AL TMVR IN MAC, VALVE DISLOCATION
new severe mitral regurgitation with a dislocation of the mitral prosthetic valve from the annulus toward the left atrium (Fig 1A). At day 17 the patient underwent a redo procedure, which was done through a left transatrial approach with median sternotomy and the use of CPB, bicaval cannulation, and cardioplegic arrest. This confirmed the etiology of the severe mitral regurgitation to be dislocation of the prosthetic mitral valve toward the left atrium and trapping of the anterior mitral valve leaflet below the prosthesis. After applying traction to the interventricular septum, the valve was completely released from the annulus. The valve was manually collapsed and was repositioned back into the native mitral valve annulus before being deployed with the use of an expandable balloon. To prevent repeat dislocation, the valve was additionally fixed with three sutures between the valve stent frame and the anterior mitral valve leaflet annular site. The postoperative echocardiogram showed normal positioning and function of the aortic prosthetic valve and a residual moderate paravalvular leak of the prosthetic mitral valve (Fig 1B). After 2 weeks of further hospitalization, the patient was successfully
Ann Thorac Surg 2016;102:e287–90
discharged home. At 5 months’ follow-up, the patient was in New York Heart Association functional class I or II with echocardiography showing no deterioration in the degree of paravalvular regurgitation.
Patient 2 A 69-year-old man with a history of aortic and mitral valve disease presented to our institute with worsening exertional dyspnea (New York Heart Association functional class III). Echocardiography showed severe aortic valve stenosis, moderate mitral valve regurgitation, and mild tricuspid regurgitation along with heavy calcification of the aortic and mitral valve annuli and the aortomitral continuity. The diagnostic coronary angiography showed obstructed coronary arteries. The patient underwent a surgical review and was accepted for aortic and mitral valve replacement, tricuspid valve repair, and a maze procedure. At surgery, aortic valve replacement was performed with a Sorin Perceval S bioprosthesis valve (Sorin Group, Mirandola, Italy), the tricuspid valve was repaired with an Edwards Physio ring, 34 mm, and the maze procedure was performed with left side epicardial cryoablation. The procedure on the mitral valve, however, was abandoned owing to the operative finding of the heavy MAC. After the operation, cardiac CT was performed to evaluate the degree of MAC and to facilitate sizing of the annulus. Two weeks later, the patient underwent a transapical transcatheter mitral valve implantation of an Edwards Sapiens S3 29-mm valve without complication (Fig 2). In contrast to the first case, we elected to use three key strategies to avoid a repetition of valve dislocation. The first was to use a larger valve size (oversizing) than indicated by the CT and echocardiographic measurements. The second was to position the valve deeper in the annular plane (60% ventricular to 40% mitral annular plane). The third was to perform overdilatation of the expandable valve by 3 mL more than the manufacturer’s recommendations at the ventricular part of the prosthetic valve. The postoperative echocardiogram and CT showed a good position and functioning of the aortic and mitral valves. On day 9, the patient was discharged home in good condition (Fig 3).
Comment
Fig 1. (A) Transesophageal echocardiograph showing the dislocated valve toward the left atrium (LA, open arrow) and the transcatheter aortic valve implantation in situ (closed arrow). (B) Cardiac computed tomography scan showing the final positions of both valves after the redeployment of the mitral valve. (AA ¼ ascending aorta; Ao ¼ aortic root; LV ¼ left ventricle.)
In the current report we describe two cases of TMVR in patients with severe MAC. The first case was complicated by dislocation of the TMVR toward the left atrium. After conducting a root cause analysis, we identified three contributory factors to the occurrence. These were used for evaluating the second case, which was thereafter performed without periprocedural complication or subsequent valve dislocation. Owing to the difficulties that MAC poses for surgical intervention on the mitral valve, there has been a necessary development of alternative strategies to treat patients with this condition. Perhaps the technique that has gained the most interest is TMVR using balloon-expandable
Ann Thorac Surg 2016;102:e287–90
CASE REPORT HULMAN ET AL TMVR IN MAC, VALVE DISLOCATION
e289
Fig 2. (A) Preoperative cardiac computed tomography scan showing the Sorin Perceval valve (closed arrow), the tricuspid annular ring, and the heavily calcified mitral annulus (MAC). (B) Transesophageal echocardiography showing the implanted mitral prosthetic valve (open arrow).
valves. Although initial reports have been promising [2–4], concerns still remain about subsequent valve dislocation and the occurrence of significant paravalvular regurgitation. Additionally there remains a lack of consensus as to the approach to use (transapical, transatrial, or completely transcutaneous) and the precise method for sizing of the annulus. It has therefore become imperative to develop registry data on TMVR in MAC to enable the pooling of worldwide experience to optimize patient outcomes and to mitigate complications. We observed in the current report that TMVR with aortic balloon-expandable valves is feasible in patients with significant MAC. Similar to other authors [4, 6] we used the Edwards Sapiens S3 and XT bioprosthesis valves. Other reports exist of other devices also being successfully used. Use of TMVR in MAC was reported by El-Eshmawi and colleagues [7] with the Melody transcatheter pulmonary balloon-expandable valve (transatrial access), Lim and associates [8] with the Lotus valve, and Mellert and coworkers [3] with the DirectFlow valve. As worldwide experience increases, the true incidence of prosthetic mitral valve dislocation and paravalvular regurgitation will become more transparent. Based on our experience, we identified three potential factors that may contribute to both of these complications: 1. Prosthetic valve size. In the second patient we used a 29-mm valve instead of the 26-mm valve that was used in the first patient to avoid this complication. In
Fig 3. (A) Fluoroscopy showing the overdilatation of the ventricular part of the valve and the deeper valve positioning into the left ventricle. (B) Cardiac computed tomography scan showing the position of the implanted prosthetic mitral valve.
our opinion, deployment of the larger valve size (oversizing) reduces the risk for dislocation owing to better anchoring to the native mitral valve annulus. In the absence of a validated standard method for mitral annulus sizing, operators have extrapolated from transcatheter aortic valve replacement experience and used a variety of sizing approaches, including echocardiography, three-dimensional transesophageal echocardiography, cardiac CT, and balloon sizing techniques. We consider cardiac CT to be the optimal method for sizing the mitral valve annulus and recommend multiphase electrocardiograph-gated CT to assess the mitral valve annulus size at various stages of the cardiac cycle before deciding on a specific valve size. 2. Valve positioning in the annular plane. In the second patient, the valve was positioned deeper in the annular plane, with 60% in the ventricular and 40% in the atrial annular plane. In our opinion, the valve has a more stable anchoring with this position, so the risk for valve dislocation is reduced.
e290
CASE REPORT HULMAN ET AL TMVR IN MAC, VALVE DISLOCATION
3. Expandable balloon dilatation. In the first patient the volume that was used for balloon dilatation was according to the manufacturer’s guidelines. In our opinion, an overdilatation of the balloon at the ventricular part of the prosthetic valve provides better stabilization of the prosthetic valve in the native calcified annulus. In the second patient, the balloon was overdilated by 3 mL above the manufacturer’s recommended guidelines. A combination of all three preventive measures will increase the technical success to a comparable level as that of the open transatrial approach [2, 4]. Concerning management of the complication of dislocation, there remains a paucity of data in the literature. In our first patient, the valve was repositioned back in the native mitral annulus using an open transatrial approach by manual collapse and redeployment of the valve with the use of an expandable balloon. It was then fixed with an additional three sutures between the valve stent frame and the annulus. Alternative techniques include surgical extraction of the valve or stabilization of the prosthetic valve in the interatrial septum. Cardiac CT is the preferred modality for the diagnosis of the severity of the MAC, and should have a more liberal use in this process to plan the appropriate procedure, surgical or transcatheter. Alternative techniques are susceptible to grossly underestimating the extent, distribution, and geometry of MAC, which may result in needless and aborted sternotomies as documented in the second case. In the current report we document two different experiences of TMVR in MAC. The first case illustrates the real risk of valve dislocation in patients undergoing
Ann Thorac Surg 2016;102:e287–90
TMVR for MAC. Subsequently we report a second case of uncomplicated TMVR in MAC in which specific strategies were used to ensure an optimal outcome. Finally we show the rare imaging findings of both of these cases.
References 1. Vohra HA, Whistance RN, Bezuska L, Livesey SA. Surgery for non-rheumatic calcific mitral stenosis. J Heart Valve Dis 2011;20:624–5. 2. Wilbring M, Alexiou K, Tugtekin SM, et al. Pushing the limits-further evolutions of transcatheter valve procedures in the mitral position, including valve-in-valve, valve-in-ring and valve-in-native-ring. J Thorac Cardiovasc Surg 2014;147: 210–9. 3. Mellert F, Sinning JM, Werner N, et al. First–in-human transapical mitral valve replacement using the Direct Flow Medical aortic valve prosthesis. Eur Heart J 2015 Aug 14;36(31):2119; Epub 2015 May 20. 4. Puri R, Abdul-Jawad Altisent O, Del-Tingo M, et al. Transcatheter mitral valve implantation for inoperable severely caicified native mitral valve disease: a systematic review. Catheter Cardiovasc Interv 2016;87:540–8. 5. Holmes DR Jr, Mack MJ, Kaul S, et al. 2012 ACCF/AATS/ SCAI/STS Expert consensus document on trancatheter aortic valve replacement. J Am Coll Cardiol 2012;59:1200–54. 6. Lee R, Fukuhara S, George I, Borger MA. Mitral valve replacement with a transcatheter valve in the setting of severe mitral annular calcification. J Thorac Cadiovasc Surg 2016;151: e47–9. 7. El-Eshmawi A, Love B, Bhatt HV, Pawale A, Boateng P, Adams DH. Direct access implantation of a Melody valve in native mitral valve hybrid approach in the presence of extensive mitral annular calcification. Ann Thorac Surg 2015;99:1085. 8. Lim ZY, Boix R, Prendergast B, et al. First reported case of transcatheter mitral valve implantation in mitral annular calcification with a fully repositionable and self-expanding valve. Circ Cardiovasc Interv 2015;8(11):e003031.