Portal de Periódicos da CAPES

Percutaneous Implantation of CoreValve Aortic Prostheses in Patients With a Mechanical Mitral Valve

2009; Elsevier BV; Volume: 88; Issue: 5 Linguagem: Inglês

10.1016/j.athoracsur.2009.07.028

1552-6259

Giuseppe Bruschi, Federico De Marco, Jacopo Oreglia, Paola Colombo, Pasquale Fratto, Francesca Lullo, Roberto Paino, Maria Frigerio, Luigi Martinelli, Silvio Klugmann,

Cardiac Structural Anomalies and Repair

Concerns exist in the field of transcatheter aortic valve implantation regarding the treatment of patients with mechanical mitral valve for possible interference between the percutaneous aortic valve and the mechanical mitral prosthesis. We report our experience with percutaneous aortic valve implantation in 4 patients with severe aortic stenosis, previously operated on for mitral valve replacement with a mechanical prosthesis. All patients underwent uneventful percutaneous retrograde CoreValve implantation (CoreValve Inc, Irvine, CA). No deformation of the nitinol tubing of the prostheses (ie, neither distortion nor malfunction of the mechanical valve in the mitral position) occurred in any of the patients. All patients are alive and asymptomatic at a mean follow-up of 171 days. Concerns exist in the field of transcatheter aortic valve implantation regarding the treatment of patients with mechanical mitral valve for possible interference between the percutaneous aortic valve and the mechanical mitral prosthesis. We report our experience with percutaneous aortic valve implantation in 4 patients with severe aortic stenosis, previously operated on for mitral valve replacement with a mechanical prosthesis. All patients underwent uneventful percutaneous retrograde CoreValve implantation (CoreValve Inc, Irvine, CA). No deformation of the nitinol tubing of the prostheses (ie, neither distortion nor malfunction of the mechanical valve in the mitral position) occurred in any of the patients. All patients are alive and asymptomatic at a mean follow-up of 171 days. In recent years, transcatheter aortic valve implantation (TAVI) has emerged as a valuable option to treat patients with symptomatic aortic stenosis not being considered for surgery because of significant comorbidities, such as old age, multiple previous cardiac operations, chronic obstructive pulmonary disease, liver or renal failure, and diffuse atherosclerosis [1Cribier A. Eltchaninoff H. Bash A. et al.Percutaneous transcatheter implantation of an aortic valve prosthesis for calcific aortic stenosis: first human case description.Circulation. 2002; 106: 3006-3008Crossref PubMed Scopus (2521) Google Scholar, 2Cribier A. Eltchaninoff H. Tron C. et al.Treatment of calcific aortic stenosis with the percutaneous heart valve mid-term follow-up from the initial feasibility studies: the French experience.J Am Coll Cardiol. 2006; 47: 1214-1223Abstract Full Text Full Text PDF PubMed Scopus (679) Google Scholar, 3Grube E. Buellesfeld L. Mueller R. et al.Progress and current status of percutaneous aortic valve replacement: results of three device generations of the CoreValve Revalving system.Circ Cardiovasc Intervent. 2008; 1: 167-175Crossref PubMed Scopus (312) Google Scholar]. From this cohort of patients, another set of patients have been excluded at the beginning of the TAVI experience (ie, those patients who have mechanical mitral prosthesis); this was decided because concerns exist for possible interference between the percutaneous aortic valve and the mechanical mitral prosthesis.We report our experience with percutaneous aortic valve replacement using the CoreValve Re-valving (CoreValve Inc, Irvine, CA) in 4 patients with severe aortic stenosis, previously operated on for mitral valve replacement with a mechanical prosthesis.All patient evaluations were made by the "heart team" (composed of a cardiac surgeon, an interventional cardiologist, the referring cardiologist, a cardiac anesthesiologist, and a radiologist), according to the statement of the European Association of Cardio-Thoracic Surgery and the European Society of Cardiology. This team accomplished the following: (1) confirmed the severity of aortic stenosis, (2) evaluated patients' symptoms, (3) analyzed surgical risk and evaluated patient life expectancy and quality of life, and (4) assessed the feasibility and exclusion of contraindications for TAVI [4Vahaniana A. Alfieri O. Al-Attar N. et al.Transcatheter valve implantation for patients with aortic stenosis: a position statement from the European Association of Cardio-Thoracic Surgery (EACTS) and the European Society of Cardiology (ESC), in collaboration with the European Association of Percutaneous Cardiovascular Interventions (EAPCI).Eur J Cardiothorac Surg. 2008; 34: 1-8Crossref PubMed Scopus (248) Google Scholar]. After the "heart team" evaluation, fully percutaneous aortic valve implantation with a CoreValve prosthesis (CoreValve Inc) was preferred for the following patients because of high-risk surgical re-do procedures and comorbidities. All patients had a logistic Euroscore > 23% (range, 23% to 44%) and a Society of Thoracic Surgeons' risk of morbidity and mortality > 33%. All patients signed an informed consent.Case ReportsPatient 1Patient 1 was a 72-year-old woman affected by severe aortic stenosis with an echocardiographic aortic valve area of 0.6 cm2, with a depressed left ventricular function of 21%, and pulmonary hypertension. She had repeated episodes of syncope. In 1987, she underwent mitral valve replacement with a Sorin allcarbon monodisk no. 31 (Sorin, Milan, Italy) for mitral stenosis. In 1993, she underwent a neurosurgical operation for an intraparenchymal hematoma. Associated comorbidity was liver cirrhosis in chronic hepatitis C infection. She was in New York Heart Association functional class III dyspnea.Patient 2Patient 2 was a 77-year-old woman with a significant aortic stenosis with an echocardiographic aortic valve area of 0.6 cm2, a left ventricular ejection fraction of 40%, and pulmonary hypertension. In 1996, the patient underwent a mitral valve replacement with a Sorin allcarbon monodisk no. 29 for mitral stenosis (Sorin). She was in New York Heart Association functional class III and also has chronic obstructive pulmonary disease.Patient 3Patient 3 was a 60-year-old woman with severe valvular cardiomyopathy that was screened for heart transplantation at our center. She was in New York Heart Association functional class IV, with a cardiac index of 1.3 L/min/m2. She had a combined aortic stenosis and 3+/4+ aortic insufficiency with a depressed left ventricular ejection fraction of 21% and also has pulmonary hypertension. In 1996, the patient underwent mitral commissurotomy when she was 19 years of age, and then she had a mitral valve replacement with a Sorin allcarbon monodisk no. 25. An implantable cardioverter defibrillator was implanted in 2008. After case evaluation with the transplant team, the patient was screened for heart transplantation enlisting and considering the high-surgical risk for standard aortic valve replacement, it was decided to treat the patient with percutaneous valve implantation as bridge-to-future heart transplant.Patient 4Patient 4 was a 77-year-old woman affected by severe aortic stenosis, with a left ventricular ejection fraction of 50%. She underwent mitral commissurotomy in 1970, and then she had mitral valve replacement with a Sorin bicarbon no. 29 in 1998. She was in New York Heart Association functional class III. A chest computerized tomographic scan revealed a "porcelain" aorta.All patients underwent coronary angiography with no evidence of coronary stenosis. The computed tomographic scan of the great arteries demonstrated in all patients an iliac-femoral artery diameter large enough for use of the CoreValve introducer sheath (18F). Pre-procedural anti-platelet treatment consisted of acetylsalicylic acid (100 mg qd) and clopidogrel 75 mg qd after a loading dose of 300 mg.The CoreValve ReValving System consists of three unique components: (1) a self-expanding support frame with a tri-leaflet porcine pericardial tissue valve; (2) an 18F catheter delivery system and a disposable loading system; and (3) the self-expanding support frame has a diamond-cell configuration made from laser cut nitinol tubing and incorporates three different areas of radial force. The upper part (aortic level) of the frame increases the prosthesis fixation to the aorta wall and axes the system parallel to the blood flow. The middle part (commissural level) carries the valve (porcine pericardium). The complete support frame is 45 mm in axial length. Despite crossing the coronary ostia, the convex shape at this level is opposed to the concavity of the coronary sinus to preserve natural hemodynamic flow. The CoreValve prosthesis is preloaded and compressed in an 18F outer diameter catheter [5Grube E. Laborde J.C. Gerckens U. et al.Percutaneous implantation of the CoreValve self-expanding valve prosthesis in high-risk patients with aortic valve disease: the Siegburg First-in-Man Study.Circulation. 2006; 114: 1616-1624Crossref PubMed Scopus (626) Google Scholar, 6Leon M.B. Kodali S. Williams M. et al.Transcatheter aortic valve replacement in patients with critical aortic stenosis: rationale, device descriptions, early clinical experiences, and perspectives.Semin Thorac Cardiovasc Surg. 2006; 18: 165-174Abstract Full Text Full Text PDF PubMed Scopus (43) Google Scholar].A totally percutaneous retrograde CoreValve implantation was performed with all patients awake with local anesthesia and mild sedation and continuous systemic arterial pressure control. After placing a temporary pacing lead through a femoral vein in the patients without permanent pacemaker, the best femoral artery was accessed by a single-wall puncture under fluoroscopic and angiographic guidance. A Prostar XL 10F suture-mediated closure device (Abbott Vascular Devices Laboratories, Redwood City, CA) was placed in the femoral artery (Preclosure technique). A Cook 30-cm Check-Flo Performer 18F introducer was then inserted over an Amplatz super stiff guidewire and the native aortic valve was pre-dilated with a 22-mm Nucleus balloon (NuMED, Inc, Hopkinton, NY) in all patients. A 26-mm CoreValve prosthesis was retrogradely positioned in all patients under angiographic and fluoroscopic guidance (Fig 1) with immediate improvement of the hemodynamic status. Mean aortic gradient dropped immediately below 3 mm Hg after CoreValve deployment in all patients. No CoreValve balloon post-dilatation was needed. No deformation of the nitinol tubing of the CoreValve, neither distortion nor malfunction of the mechanical valve in mitral position occurred in any patients, as assessed by echographic and fluoroscopic evaluation (Fig 1, Fig 2). Mean postoperative echocardiographic aortic gradient was 9 mm Hg. All the procedures were uneventful, and the patients were discharged after a mean hospitalization of 12 days (range, 7 to 20 days) with aspirin (100 mg once a day) in chronic and clopidogrel (75 mg once a day) for 3 months. All patients are alive and asymptomatic at a mean follow-up of 6.5 months (range, 4 to 12 months) and 3 months echocardiogram showed a mean aortic gradient of 10 mm Hg.Fig 2Patient 1: Fully-expanded valve prosthesis across the native aortic valve. Aortogtram demonstrates good opacification of the left main and anterior descending artery and of the right coronary artery. No evidence of aortic regurgitation and no interference, neither distortion nor malfunction of the CoreValve (CoreValve Inc, Irvine, CA) or the mono-disk mechanical valve in the mitral position.View Large Image Figure ViewerDownload (PPT)CommentTranscatheter aortic valve implantation has emerged as an alternative therapy to treat patients with symptomatic aortic stenosis not being considered for surgery because of high-risk surgical features [1Cribier A. Eltchaninoff H. Bash A. et al.Percutaneous transcatheter implantation of an aortic valve prosthesis for calcific aortic stenosis: first human case description.Circulation. 2002; 106: 3006-3008Crossref PubMed Scopus (2521) Google Scholar, 2Cribier A. Eltchaninoff H. Tron C. et al.Treatment of calcific aortic stenosis with the percutaneous heart valve mid-term follow-up from the initial feasibility studies: the French experience.J Am Coll Cardiol. 2006; 47: 1214-1223Abstract Full Text Full Text PDF PubMed Scopus (679) Google Scholar, 3Grube E. Buellesfeld L. Mueller R. et al.Progress and current status of percutaneous aortic valve replacement: results of three device generations of the CoreValve Revalving system.Circ Cardiovasc Intervent. 2008; 1: 167-175Crossref PubMed Scopus (312) Google Scholar]. Patients with a mechanical mitral valve usually have been excluded from this therapy because concerns exist about possible interference between the two prostheses, particularly during the expansion of the new aortic valve and the potential increased risk of valve embolization. In fact, the presence of previous mitral valve surgery is considered an exclusion criterion also in the currently ongoing trial (placement of aortic transcatheter valves [known as the PARTNER trial]), which compares TAVI, surgical aortic valve replacement, and medical therapy [7ClinicalTrial.org. Placement of AoRTic TraNscathetER Valve (PARTNER) trial. NCT00530894. http://clinicaltrials.gov/ct2/show/NCT00530894.Google Scholar]. From the anatomical point of view, the mid-portion of the aortic leaflet of the mitral valve is related to the commissure between the noncoronary and left coronary cusps of the aortic valve. The posterior quadrant of the outflow tract of the left ventricle consists of an extensive fibrous curtain that extends from the fibrous skeleton of the heart across the aortic leaflet of the mitral valve, and supports the leaflets of the aortic valve in the area of aorto-mitral continuity [8Mill M.R. Wilcox B.R. Anderson R.H. Surgical anatomy of the heart.in: Cohn L.H. Edmunds Jr, L.H. Cardiac surgery of the adults. 3rd ed. McGraw-Hill, New York, NY2003: 31-52Google Scholar].We believe that this is the first report of TAVI with the CoreValve aortic prosthesis in patients with mechanical mitral valves. Published cases consist only of 1 patient from Rodes-Cabau and colleagues [9Rodes-Cabau J. Dumont E.Miro′ S. et al.Apical aortic valve implantation in a patient with a mechanical valve prosthesis in mitral position.Circ Cardiovasc Intervent. 2008; 1: 233-235Crossref PubMed Scopus (28) Google Scholar] who underwent trans-apical aortic valve implantation of a Edwards Sapein prosthesis (Edwards Lifesciences, Irvine, CA) in a 67-year-old man previously operated on for coronary artery bypass grafting and mitral valve replacement with a St. Jude mechanical valve (St. Jude Medical, St. Paul, MN). As reported by the authors, the presence of a mechanical valve in mitral position might complicate TAVI because of the reduction of the mitro-aortic space to accommodate the transcatheter valve, and because the presence of a mechanical valve can limit the expansion of the percutaneous prosthesis. Our experience shows that CoreValve implantation can be performed successfully in patients with mechanical mitral valves. Concerns might exist regarding the use of the CoreValve in this group of patients because of the self-expanding support frame of the valve and possible under-expansion or deformation of the prosthesis. To this regard, we did not observe any deformation of the nitinol tubing of the CoreValve and no distortion of the housing or interference with the leaflet excursion of the mechanical mitral valve, as assessed by fluoroscopy and serial echocardiographic evaluation. Our experience, characterized by a multidisciplinary approach, is necessary to offer the safest conditions and care for patients, which demonstrates the feasibility of this new and promising technique also for this cohort of patients; indeed, prospective studies involving larger number of patients are also required to confirm these beneficial findings at long-term follow-up. In recent years, transcatheter aortic valve implantation (TAVI) has emerged as a valuable option to treat patients with symptomatic aortic stenosis not being considered for surgery because of significant comorbidities, such as old age, multiple previous cardiac operations, chronic obstructive pulmonary disease, liver or renal failure, and diffuse atherosclerosis [1Cribier A. Eltchaninoff H. Bash A. et al.Percutaneous transcatheter implantation of an aortic valve prosthesis for calcific aortic stenosis: first human case description.Circulation. 2002; 106: 3006-3008Crossref PubMed Scopus (2521) Google Scholar, 2Cribier A. Eltchaninoff H. Tron C. et al.Treatment of calcific aortic stenosis with the percutaneous heart valve mid-term follow-up from the initial feasibility studies: the French experience.J Am Coll Cardiol. 2006; 47: 1214-1223Abstract Full Text Full Text PDF PubMed Scopus (679) Google Scholar, 3Grube E. Buellesfeld L. Mueller R. et al.Progress and current status of percutaneous aortic valve replacement: results of three device generations of the CoreValve Revalving system.Circ Cardiovasc Intervent. 2008; 1: 167-175Crossref PubMed Scopus (312) Google Scholar]. From this cohort of patients, another set of patients have been excluded at the beginning of the TAVI experience (ie, those patients who have mechanical mitral prosthesis); this was decided because concerns exist for possible interference between the percutaneous aortic valve and the mechanical mitral prosthesis. We report our experience with percutaneous aortic valve replacement using the CoreValve Re-valving (CoreValve Inc, Irvine, CA) in 4 patients with severe aortic stenosis, previously operated on for mitral valve replacement with a mechanical prosthesis. All patient evaluations were made by the "heart team" (composed of a cardiac surgeon, an interventional cardiologist, the referring cardiologist, a cardiac anesthesiologist, and a radiologist), according to the statement of the European Association of Cardio-Thoracic Surgery and the European Society of Cardiology. This team accomplished the following: (1) confirmed the severity of aortic stenosis, (2) evaluated patients' symptoms, (3) analyzed surgical risk and evaluated patient life expectancy and quality of life, and (4) assessed the feasibility and exclusion of contraindications for TAVI [4Vahaniana A. Alfieri O. Al-Attar N. et al.Transcatheter valve implantation for patients with aortic stenosis: a position statement from the European Association of Cardio-Thoracic Surgery (EACTS) and the European Society of Cardiology (ESC), in collaboration with the European Association of Percutaneous Cardiovascular Interventions (EAPCI).Eur J Cardiothorac Surg. 2008; 34: 1-8Crossref PubMed Scopus (248) Google Scholar]. After the "heart team" evaluation, fully percutaneous aortic valve implantation with a CoreValve prosthesis (CoreValve Inc) was preferred for the following patients because of high-risk surgical re-do procedures and comorbidities. All patients had a logistic Euroscore > 23% (range, 23% to 44%) and a Society of Thoracic Surgeons' risk of morbidity and mortality > 33%. All patients signed an informed consent. Case ReportsPatient 1Patient 1 was a 72-year-old woman affected by severe aortic stenosis with an echocardiographic aortic valve area of 0.6 cm2, with a depressed left ventricular function of 21%, and pulmonary hypertension. She had repeated episodes of syncope. In 1987, she underwent mitral valve replacement with a Sorin allcarbon monodisk no. 31 (Sorin, Milan, Italy) for mitral stenosis. In 1993, she underwent a neurosurgical operation for an intraparenchymal hematoma. Associated comorbidity was liver cirrhosis in chronic hepatitis C infection. She was in New York Heart Association functional class III dyspnea.Patient 2Patient 2 was a 77-year-old woman with a significant aortic stenosis with an echocardiographic aortic valve area of 0.6 cm2, a left ventricular ejection fraction of 40%, and pulmonary hypertension. In 1996, the patient underwent a mitral valve replacement with a Sorin allcarbon monodisk no. 29 for mitral stenosis (Sorin). She was in New York Heart Association functional class III and also has chronic obstructive pulmonary disease.Patient 3Patient 3 was a 60-year-old woman with severe valvular cardiomyopathy that was screened for heart transplantation at our center. She was in New York Heart Association functional class IV, with a cardiac index of 1.3 L/min/m2. She had a combined aortic stenosis and 3+/4+ aortic insufficiency with a depressed left ventricular ejection fraction of 21% and also has pulmonary hypertension. In 1996, the patient underwent mitral commissurotomy when she was 19 years of age, and then she had a mitral valve replacement with a Sorin allcarbon monodisk no. 25. An implantable cardioverter defibrillator was implanted in 2008. After case evaluation with the transplant team, the patient was screened for heart transplantation enlisting and considering the high-surgical risk for standard aortic valve replacement, it was decided to treat the patient with percutaneous valve implantation as bridge-to-future heart transplant.Patient 4Patient 4 was a 77-year-old woman affected by severe aortic stenosis, with a left ventricular ejection fraction of 50%. She underwent mitral commissurotomy in 1970, and then she had mitral valve replacement with a Sorin bicarbon no. 29 in 1998. She was in New York Heart Association functional class III. A chest computerized tomographic scan revealed a "porcelain" aorta.All patients underwent coronary angiography with no evidence of coronary stenosis. The computed tomographic scan of the great arteries demonstrated in all patients an iliac-femoral artery diameter large enough for use of the CoreValve introducer sheath (18F). Pre-procedural anti-platelet treatment consisted of acetylsalicylic acid (100 mg qd) and clopidogrel 75 mg qd after a loading dose of 300 mg.The CoreValve ReValving System consists of three unique components: (1) a self-expanding support frame with a tri-leaflet porcine pericardial tissue valve; (2) an 18F catheter delivery system and a disposable loading system; and (3) the self-expanding support frame has a diamond-cell configuration made from laser cut nitinol tubing and incorporates three different areas of radial force. The upper part (aortic level) of the frame increases the prosthesis fixation to the aorta wall and axes the system parallel to the blood flow. The middle part (commissural level) carries the valve (porcine pericardium). The complete support frame is 45 mm in axial length. Despite crossing the coronary ostia, the convex shape at this level is opposed to the concavity of the coronary sinus to preserve natural hemodynamic flow. The CoreValve prosthesis is preloaded and compressed in an 18F outer diameter catheter [5Grube E. Laborde J.C. Gerckens U. et al.Percutaneous implantation of the CoreValve self-expanding valve prosthesis in high-risk patients with aortic valve disease: the Siegburg First-in-Man Study.Circulation. 2006; 114: 1616-1624Crossref PubMed Scopus (626) Google Scholar, 6Leon M.B. Kodali S. Williams M. et al.Transcatheter aortic valve replacement in patients with critical aortic stenosis: rationale, device descriptions, early clinical experiences, and perspectives.Semin Thorac Cardiovasc Surg. 2006; 18: 165-174Abstract Full Text Full Text PDF PubMed Scopus (43) Google Scholar].A totally percutaneous retrograde CoreValve implantation was performed with all patients awake with local anesthesia and mild sedation and continuous systemic arterial pressure control. After placing a temporary pacing lead through a femoral vein in the patients without permanent pacemaker, the best femoral artery was accessed by a single-wall puncture under fluoroscopic and angiographic guidance. A Prostar XL 10F suture-mediated closure device (Abbott Vascular Devices Laboratories, Redwood City, CA) was placed in the femoral artery (Preclosure technique). A Cook 30-cm Check-Flo Performer 18F introducer was then inserted over an Amplatz super stiff guidewire and the native aortic valve was pre-dilated with a 22-mm Nucleus balloon (NuMED, Inc, Hopkinton, NY) in all patients. A 26-mm CoreValve prosthesis was retrogradely positioned in all patients under angiographic and fluoroscopic guidance (Fig 1) with immediate improvement of the hemodynamic status. Mean aortic gradient dropped immediately below 3 mm Hg after CoreValve deployment in all patients. No CoreValve balloon post-dilatation was needed. No deformation of the nitinol tubing of the CoreValve, neither distortion nor malfunction of the mechanical valve in mitral position occurred in any patients, as assessed by echographic and fluoroscopic evaluation (Fig 1, Fig 2). Mean postoperative echocardiographic aortic gradient was 9 mm Hg. All the procedures were uneventful, and the patients were discharged after a mean hospitalization of 12 days (range, 7 to 20 days) with aspirin (100 mg once a day) in chronic and clopidogrel (75 mg once a day) for 3 months. All patients are alive and asymptomatic at a mean follow-up of 6.5 months (range, 4 to 12 months) and 3 months echocardiogram showed a mean aortic gradient of 10 mm Hg. Patient 1Patient 1 was a 72-year-old woman affected by severe aortic stenosis with an echocardiographic aortic valve area of 0.6 cm2, with a depressed left ventricular function of 21%, and pulmonary hypertension. She had repeated episodes of syncope. In 1987, she underwent mitral valve replacement with a Sorin allcarbon monodisk no. 31 (Sorin, Milan, Italy) for mitral stenosis. In 1993, she underwent a neurosurgical operation for an intraparenchymal hematoma. Associated comorbidity was liver cirrhosis in chronic hepatitis C infection. She was in New York Heart Association functional class III dyspnea. Patient 1 was a 72-year-old woman affected by severe aortic stenosis with an echocardiographic aortic valve area of 0.6 cm2, with a depressed left ventricular function of 21%, and pulmonary hypertension. She had repeated episodes of syncope. In 1987, she underwent mitral valve replacement with a Sorin allcarbon monodisk no. 31 (Sorin, Milan, Italy) for mitral stenosis. In 1993, she underwent a neurosurgical operation for an intraparenchymal hematoma. Associated comorbidity was liver cirrhosis in chronic hepatitis C infection. She was in New York Heart Association functional class III dyspnea. Patient 2Patient 2 was a 77-year-old woman with a significant aortic stenosis with an echocardiographic aortic valve area of 0.6 cm2, a left ventricular ejection fraction of 40%, and pulmonary hypertension. In 1996, the patient underwent a mitral valve replacement with a Sorin allcarbon monodisk no. 29 for mitral stenosis (Sorin). She was in New York Heart Association functional class III and also has chronic obstructive pulmonary disease. Patient 2 was a 77-year-old woman with a significant aortic stenosis with an echocardiographic aortic valve area of 0.6 cm2, a left ventricular ejection fraction of 40%, and pulmonary hypertension. In 1996, the patient underwent a mitral valve replacement with a Sorin allcarbon monodisk no. 29 for mitral stenosis (Sorin). She was in New York Heart Association functional class III and also has chronic obstructive pulmonary disease. Patient 3Patient 3 was a 60-year-old woman with severe valvular cardiomyopathy that was screened for heart transplantation at our center. She was in New York Heart Association functional class IV, with a cardiac index of 1.3 L/min/m2. She had a combined aortic stenosis and 3+/4+ aortic insufficiency with a depressed left ventricular ejection fraction of 21% and also has pulmonary hypertension. In 1996, the patient underwent mitral commissurotomy when she was 19 years of age, and then she had a mitral valve replacement with a Sorin allcarbon monodisk no. 25. An implantable cardioverter defibrillator was implanted in 2008. After case evaluation with the transplant team, the patient was screened for heart transplantation enlisting and considering the high-surgical risk for standard aortic valve replacement, it was decided to treat the patient with percutaneous valve implantation as bridge-to-future heart transplant. Patient 3 was a 60-year-old woman with severe valvular cardiomyopathy that was screened for heart transplantation at our center. She was in New York Heart Association functional class IV, with a cardiac index of 1.3 L/min/m2. She had a combined aortic stenosis and 3+/4+ aortic insufficiency with a depressed left ventricular ejection fraction of 21% and also has pulmonary hypertension. In 1996, the patient underwent mitral commissurotomy when she was 19 years of age, and then she had a mitral valve replacement with a Sorin allcarbon monodisk no. 25. An implantable cardioverter defibrillator was implanted in 2008. After case evaluation with the transplant team, the patient was screened for heart transplantation enlisting and considering the high-surgical risk for standard aortic valve replacement, it was decided to treat the patient with percutaneous valve implantation as bridge-to-future heart transplant. Patient 4Patient 4 was a 77-year-old woman affected by severe aortic stenosis, with a left ventricular ejection fraction of 50%. She underwent mitral commissurotomy in 1970, and then she had mitral valve replacement with a Sorin bicarbon no. 29 in 1998. She was in New York Heart Association functional class III. A chest computerized tomographic scan revealed a "porcelain" aorta.All patients underwent coronary angiography with no evidence of coronary stenosis. The computed tomographic scan of the great arteries demonstrated in all patients an iliac-femoral artery diameter large enough for use of the CoreValve introducer sheath (18F). Pre-procedural anti-platelet treatment consisted of acetylsalicylic acid (100 mg qd) and clopidogrel 75 mg qd after a loading dose of 300 mg.The CoreValve ReValving System consists of three unique components: (1) a self-expanding support frame with a tri-leaflet porcine pericardial tissue valve; (2) an 18F catheter delivery system and a disposable loading system; and (3) the self-expanding support frame has a diamond-cell configuration made from laser cut nitinol tubing and incorporates three different areas of radial force. The upper part (aortic level) of the frame increases the prosthesis fixation to the aorta wall and axes the system parallel to the blood flow. The middle part (commissural level) carries the valve (porcine pericardium). The complete support frame is 45 mm in axial length. Despite crossing the coronary ostia, the convex shape at this level is opposed to the concavity of the coronary sinus to preserve natural hemodynamic flow. The CoreValve prosthesis is preloaded and compressed in an 18F outer diameter catheter [5Grube E. Laborde J.C. Gerckens U. et al.Percutaneous implantation of the CoreValve self-expanding valve prosthesis in high-risk patients with aortic valve disease: the Siegburg First-in-Man Study.Circulation. 2006; 114: 1616-1624Crossref PubMed Scopus (626) Google Scholar, 6Leon M.B. Kodali S. Williams M. et al.Transcatheter aortic valve replacement in patients with critical aortic stenosis: rationale, device descriptions, early clinical experiences, and perspectives.Semin Thorac Cardiovasc Surg. 2006; 18: 165-174Abstract Full Text Full Text PDF PubMed Scopus (43) Google Scholar].A totally percutaneous retrograde CoreValve implantation was performed with all patients awake with local anesthesia and mild sedation and continuous systemic arterial pressure control. After placing a temporary pacing lead through a femoral vein in the patients without permanent pacemaker, the best femoral artery was accessed by a single-wall puncture under fluoroscopic and angiographic guidance. A Prostar XL 10F suture-mediated closure device (Abbott Vascular Devices Laboratories, Redwood City, CA) was placed in the femoral artery (Preclosure technique). A Cook 30-cm Check-Flo Performer 18F introducer was then inserted over an Amplatz super stiff guidewire and the native aortic valve was pre-dilated with a 22-mm Nucleus balloon (NuMED, Inc, Hopkinton, NY) in all patients. A 26-mm CoreValve prosthesis was retrogradely positioned in all patients under angiographic and fluoroscopic guidance (Fig 1) with immediate improvement of the hemodynamic status. Mean aortic gradient dropped immediately below 3 mm Hg after CoreValve deployment in all patients. No CoreValve balloon post-dilatation was needed. No deformation of the nitinol tubing of the CoreValve, neither distortion nor malfunction of the mechanical valve in mitral position occurred in any patients, as assessed by echographic and fluoroscopic evaluation (Fig 1, Fig 2). Mean postoperative echocardiographic aortic gradient was 9 mm Hg. All the procedures were uneventful, and the patients were discharged after a mean hospitalization of 12 days (range, 7 to 20 days) with aspirin (100 mg once a day) in chronic and clopidogrel (75 mg once a day) for 3 months. All patients are alive and asymptomatic at a mean follow-up of 6.5 months (range, 4 to 12 months) and 3 months echocardiogram showed a mean aortic gradient of 10 mm Hg. Patient 4 was a 77-year-old woman affected by severe aortic stenosis, with a left ventricular ejection fraction of 50%. She underwent mitral commissurotomy in 1970, and then she had mitral valve replacement with a Sorin bicarbon no. 29 in 1998. She was in New York Heart Association functional class III. A chest computerized tomographic scan revealed a "porcelain" aorta. All patients underwent coronary angiography with no evidence of coronary stenosis. The computed tomographic scan of the great arteries demonstrated in all patients an iliac-femoral artery diameter large enough for use of the CoreValve introducer sheath (18F). Pre-procedural anti-platelet treatment consisted of acetylsalicylic acid (100 mg qd) and clopidogrel 75 mg qd after a loading dose of 300 mg. The CoreValve ReValving System consists of three unique components: (1) a self-expanding support frame with a tri-leaflet porcine pericardial tissue valve; (2) an 18F catheter delivery system and a disposable loading system; and (3) the self-expanding support frame has a diamond-cell configuration made from laser cut nitinol tubing and incorporates three different areas of radial force. The upper part (aortic level) of the frame increases the prosthesis fixation to the aorta wall and axes the system parallel to the blood flow. The middle part (commissural level) carries the valve (porcine pericardium). The complete support frame is 45 mm in axial length. Despite crossing the coronary ostia, the convex shape at this level is opposed to the concavity of the coronary sinus to preserve natural hemodynamic flow. The CoreValve prosthesis is preloaded and compressed in an 18F outer diameter catheter [5Grube E. Laborde J.C. Gerckens U. et al.Percutaneous implantation of the CoreValve self-expanding valve prosthesis in high-risk patients with aortic valve disease: the Siegburg First-in-Man Study.Circulation. 2006; 114: 1616-1624Crossref PubMed Scopus (626) Google Scholar, 6Leon M.B. Kodali S. Williams M. et al.Transcatheter aortic valve replacement in patients with critical aortic stenosis: rationale, device descriptions, early clinical experiences, and perspectives.Semin Thorac Cardiovasc Surg. 2006; 18: 165-174Abstract Full Text Full Text PDF PubMed Scopus (43) Google Scholar]. A totally percutaneous retrograde CoreValve implantation was performed with all patients awake with local anesthesia and mild sedation and continuous systemic arterial pressure control. After placing a temporary pacing lead through a femoral vein in the patients without permanent pacemaker, the best femoral artery was accessed by a single-wall puncture under fluoroscopic and angiographic guidance. A Prostar XL 10F suture-mediated closure device (Abbott Vascular Devices Laboratories, Redwood City, CA) was placed in the femoral artery (Preclosure technique). A Cook 30-cm Check-Flo Performer 18F introducer was then inserted over an Amplatz super stiff guidewire and the native aortic valve was pre-dilated with a 22-mm Nucleus balloon (NuMED, Inc, Hopkinton, NY) in all patients. A 26-mm CoreValve prosthesis was retrogradely positioned in all patients under angiographic and fluoroscopic guidance (Fig 1) with immediate improvement of the hemodynamic status. Mean aortic gradient dropped immediately below 3 mm Hg after CoreValve deployment in all patients. No CoreValve balloon post-dilatation was needed. No deformation of the nitinol tubing of the CoreValve, neither distortion nor malfunction of the mechanical valve in mitral position occurred in any patients, as assessed by echographic and fluoroscopic evaluation (Fig 1, Fig 2). Mean postoperative echocardiographic aortic gradient was 9 mm Hg. All the procedures were uneventful, and the patients were discharged after a mean hospitalization of 12 days (range, 7 to 20 days) with aspirin (100 mg once a day) in chronic and clopidogrel (75 mg once a day) for 3 months. All patients are alive and asymptomatic at a mean follow-up of 6.5 months (range, 4 to 12 months) and 3 months echocardiogram showed a mean aortic gradient of 10 mm Hg. CommentTranscatheter aortic valve implantation has emerged as an alternative therapy to treat patients with symptomatic aortic stenosis not being considered for surgery because of high-risk surgical features [1Cribier A. Eltchaninoff H. Bash A. et al.Percutaneous transcatheter implantation of an aortic valve prosthesis for calcific aortic stenosis: first human case description.Circulation. 2002; 106: 3006-3008Crossref PubMed Scopus (2521) Google Scholar, 2Cribier A. Eltchaninoff H. Tron C. et al.Treatment of calcific aortic stenosis with the percutaneous heart valve mid-term follow-up from the initial feasibility studies: the French experience.J Am Coll Cardiol. 2006; 47: 1214-1223Abstract Full Text Full Text PDF PubMed Scopus (679) Google Scholar, 3Grube E. Buellesfeld L. Mueller R. et al.Progress and current status of percutaneous aortic valve replacement: results of three device generations of the CoreValve Revalving system.Circ Cardiovasc Intervent. 2008; 1: 167-175Crossref PubMed Scopus (312) Google Scholar]. Patients with a mechanical mitral valve usually have been excluded from this therapy because concerns exist about possible interference between the two prostheses, particularly during the expansion of the new aortic valve and the potential increased risk of valve embolization. In fact, the presence of previous mitral valve surgery is considered an exclusion criterion also in the currently ongoing trial (placement of aortic transcatheter valves [known as the PARTNER trial]), which compares TAVI, surgical aortic valve replacement, and medical therapy [7ClinicalTrial.org. Placement of AoRTic TraNscathetER Valve (PARTNER) trial. NCT00530894. http://clinicaltrials.gov/ct2/show/NCT00530894.Google Scholar]. From the anatomical point of view, the mid-portion of the aortic leaflet of the mitral valve is related to the commissure between the noncoronary and left coronary cusps of the aortic valve. The posterior quadrant of the outflow tract of the left ventricle consists of an extensive fibrous curtain that extends from the fibrous skeleton of the heart across the aortic leaflet of the mitral valve, and supports the leaflets of the aortic valve in the area of aorto-mitral continuity [8Mill M.R. Wilcox B.R. Anderson R.H. Surgical anatomy of the heart.in: Cohn L.H. Edmunds Jr, L.H. Cardiac surgery of the adults. 3rd ed. McGraw-Hill, New York, NY2003: 31-52Google Scholar].We believe that this is the first report of TAVI with the CoreValve aortic prosthesis in patients with mechanical mitral valves. Published cases consist only of 1 patient from Rodes-Cabau and colleagues [9Rodes-Cabau J. Dumont E.Miro′ S. et al.Apical aortic valve implantation in a patient with a mechanical valve prosthesis in mitral position.Circ Cardiovasc Intervent. 2008; 1: 233-235Crossref PubMed Scopus (28) Google Scholar] who underwent trans-apical aortic valve implantation of a Edwards Sapein prosthesis (Edwards Lifesciences, Irvine, CA) in a 67-year-old man previously operated on for coronary artery bypass grafting and mitral valve replacement with a St. Jude mechanical valve (St. Jude Medical, St. Paul, MN). As reported by the authors, the presence of a mechanical valve in mitral position might complicate TAVI because of the reduction of the mitro-aortic space to accommodate the transcatheter valve, and because the presence of a mechanical valve can limit the expansion of the percutaneous prosthesis. Our experience shows that CoreValve implantation can be performed successfully in patients with mechanical mitral valves. Concerns might exist regarding the use of the CoreValve in this group of patients because of the self-expanding support frame of the valve and possible under-expansion or deformation of the prosthesis. To this regard, we did not observe any deformation of the nitinol tubing of the CoreValve and no distortion of the housing or interference with the leaflet excursion of the mechanical mitral valve, as assessed by fluoroscopy and serial echocardiographic evaluation. Our experience, characterized by a multidisciplinary approach, is necessary to offer the safest conditions and care for patients, which demonstrates the feasibility of this new and promising technique also for this cohort of patients; indeed, prospective studies involving larger number of patients are also required to confirm these beneficial findings at long-term follow-up. Transcatheter aortic valve implantation has emerged as an alternative therapy to treat patients with symptomatic aortic stenosis not being considered for surgery because of high-risk surgical features [1Cribier A. Eltchaninoff H. Bash A. et al.Percutaneous transcatheter implantation of an aortic valve prosthesis for calcific aortic stenosis: first human case description.Circulation. 2002; 106: 3006-3008Crossref PubMed Scopus (2521) Google Scholar, 2Cribier A. Eltchaninoff H. Tron C. et al.Treatment of calcific aortic stenosis with the percutaneous heart valve mid-term follow-up from the initial feasibility studies: the French experience.J Am Coll Cardiol. 2006; 47: 1214-1223Abstract Full Text Full Text PDF PubMed Scopus (679) Google Scholar, 3Grube E. Buellesfeld L. Mueller R. et al.Progress and current status of percutaneous aortic valve replacement: results of three device generations of the CoreValve Revalving system.Circ Cardiovasc Intervent. 2008; 1: 167-175Crossref PubMed Scopus (312) Google Scholar]. Patients with a mechanical mitral valve usually have been excluded from this therapy because concerns exist about possible interference between the two prostheses, particularly during the expansion of the new aortic valve and the potential increased risk of valve embolization. In fact, the presence of previous mitral valve surgery is considered an exclusion criterion also in the currently ongoing trial (placement of aortic transcatheter valves [known as the PARTNER trial]), which compares TAVI, surgical aortic valve replacement, and medical therapy [7ClinicalTrial.org. Placement of AoRTic TraNscathetER Valve (PARTNER) trial. NCT00530894. http://clinicaltrials.gov/ct2/show/NCT00530894.Google Scholar]. From the anatomical point of view, the mid-portion of the aortic leaflet of the mitral valve is related to the commissure between the noncoronary and left coronary cusps of the aortic valve. The posterior quadrant of the outflow tract of the left ventricle consists of an extensive fibrous curtain that extends from the fibrous skeleton of the heart across the aortic leaflet of the mitral valve, and supports the leaflets of the aortic valve in the area of aorto-mitral continuity [8Mill M.R. Wilcox B.R. Anderson R.H. Surgical anatomy of the heart.in: Cohn L.H. Edmunds Jr, L.H. Cardiac surgery of the adults. 3rd ed. McGraw-Hill, New York, NY2003: 31-52Google Scholar]. We believe that this is the first report of TAVI with the CoreValve aortic prosthesis in patients with mechanical mitral valves. Published cases consist only of 1 patient from Rodes-Cabau and colleagues [9Rodes-Cabau J. Dumont E.Miro′ S. et al.Apical aortic valve implantation in a patient with a mechanical valve prosthesis in mitral position.Circ Cardiovasc Intervent. 2008; 1: 233-235Crossref PubMed Scopus (28) Google Scholar] who underwent trans-apical aortic valve implantation of a Edwards Sapein prosthesis (Edwards Lifesciences, Irvine, CA) in a 67-year-old man previously operated on for coronary artery bypass grafting and mitral valve replacement with a St. Jude mechanical valve (St. Jude Medical, St. Paul, MN). As reported by the authors, the presence of a mechanical valve in mitral position might complicate TAVI because of the reduction of the mitro-aortic space to accommodate the transcatheter valve, and because the presence of a mechanical valve can limit the expansion of the percutaneous prosthesis. Our experience shows that CoreValve implantation can be performed successfully in patients with mechanical mitral valves. Concerns might exist regarding the use of the CoreValve in this group of patients because of the self-expanding support frame of the valve and possible under-expansion or deformation of the prosthesis. To this regard, we did not observe any deformation of the nitinol tubing of the CoreValve and no distortion of the housing or interference with the leaflet excursion of the mechanical mitral valve, as assessed by fluoroscopy and serial echocardiographic evaluation. Our experience, characterized by a multidisciplinary approach, is necessary to offer the safest conditions and care for patients, which demonstrates the feasibility of this new and promising technique also for this cohort of patients; indeed, prospective studies involving larger number of patients are also required to confirm these beneficial findings at long-term follow-up.