VARC-3 defined outcome of valve-in-valve transcatheter aortic valve implantation in stentless compared with stented aortic bioprostheses.

BACKGROUND: Valve-in-valve (ViV) transcatheter aortic valve implantation (TAVI) is a viable alternative to redo surgery in selected patients with bioprosthetic valve dysfunction. Most ViV-TAVI procedures have been performed in stented bioprosthetic valves (ST); stentless bioprostheses (SL) lack fluoroscopic markers and could be more challenging for ViV-TAVI. Data on more recent patients applying Valve Academic Research Consortium (VARC)-3 defined outcomes are scarce. We compared patient characteristics, procedural outcomes, and 5-year mortality of patients with SL versus ST aortic bioprosthetic valve failure undergoing ViV-TAVI. METHODS: Patients undergoing ViV-TAVI between 2007 and 2022 (52.5% of cases after 2015) at 3 German centers were included in this analysis. The co-primary outcome measures were technical success, device success, and early safety defined by VARC-3. Mortality was assessed up to 5 years. RESULTS: Overall, 43 (11.8%) SL and 313 (88.2%) ST ViV-TAVI were included. Patients were comparable with regard to age, sex, clinically relevant baseline comorbidities, and surgical risk. Technical success (SL: 83.7% versus ST: 79.9%, p = 0.552), device success (SL: 67.4% versus ST: 54.3%, p = 0.105), and early safety (SL: 74.4% versus ST: 66.5%, p = 0.296) were comparable between groups. The 30-day mortality (SL: 7.0% versus ST: 2.6%, p = 0.136) and 5-year mortality rates (SL: 23.3% versus ST: 24.6%, p = 0.874) were not significantly different between groups. CONCLUSION: SL and ST ViV-TAVI led to comparable short-term outcomes according to VARC-3- defined endpoints and similar mortality rates up to 5 years of follow-up. VARC-3 defined technical success, device success, and early safety as well as 5-year all-cause mortality in patients undergoing valve-in-valve transcatheter aortic valve implantation (ViV-TAVI) into stentless (SL) compared with stented (ST) failed aortic bioprostheses.

A case of freestyle valve reoperation 23 years after the first operation.

We present a case of redo stentless valve operation in a 73-year-old man who underwent aortic valve replacement via the subcoronary approach with a freestyle aortic bioprosthesis 23 years ago at our institution. He was referred for surgery because an echocardiogram showed severe aortic regurgitation due to structural valve deterioration, and aortic valve replacement was planned. Severe circumferential calcification and adhesion were noted during the surgery between the freestyle and native roots. Redo-aortic valve replacement was successful despite the technical difficulty. In stentless valve reoperations following aortic valve replacement via the subcoronary method, the planning of valve-in-valve transcatheter aortic valve implantation and sutureless valve implantation may be a practical and safe strategy.

The Impact of Postoperative Thrombocytopenia in a Stentless Bioprosthetic Valve (SOLO SMART) / 日本心臓血管外科学会雑誌

Background: SOLO SMART (SOLO) was introduced in Japan as a new stentless tissue valve in April 2016. Postoperative thrombocytopenia has been reported to occurs after aortic valve replacement (AVR) using SOLO. Methods: The aim of our study was to evaluate the difference in incidence and clinical impact of postoperative thrombocytopenia in patients receiving AVR between SOLO group and stented bioprosthetic valve (Stented) group. We evaluated 67 patients who underwent AVR with bioprosthetic valve for AS between April 2017 and March 2020. Severe thrombocytopenia was defined as the lowest postoperative platelet count of < 5.0×104/μl. We divided patients with AVR into SOLO and Stented groups, and compared the surgical results, prevalence of thrombocytopenia, and changes in platelet count. Results: Postoperative aortic valve area (AVA) and peak pressure gradient (P-PG) were significantly improved in the SOLO group. The lowest postoperative platelet count was significantly lower in the SOLO group. Severe thrombocytopenia was observed in 75% of the patients in the SOLO group and 7% of those in the Stented group. As a factor that causes postoperative thrombocytopenia, use of SOLO, age at surgery, and body surface area (BSA), showed significant differences (p＜0.05). Although the platelet count had the lowest value on the 2nd to 4th day after the operation, then recovered spontaneously, and at 1 month after the operation, the platelet level improved to normal values. However, in the Stented group, the platelet level recovered to the preoperative platelet level 1 week after operation, but in the SOLO group, the preoperative platelet level didn't recover even after 3 months, and as a result, it suggest that platelet recovery was prolonged in the SOLO group. Conclusion: Use of SOLO was an independent risk factor of severe thrombocytopenia after AVR. Although no clinically serious hemorrhagic complication was observed, use of SOLO may prolong postoperative platelet recovery. In consideration of the risk of thrombocytopenia, it was considered to be advantageous to select the SOLO for SAVR in cases with a narrow annulus diameter.

Midterm outcomes of subcoronary stentless porcine valve versus stented aortic valve replacement.

INTRODUCTION: Stentless porcine xenografts are versatile bioprosthetic valves with the advantage of improved hemodynamics that mimic the function of the native aortic valve. However, these bioprostheses are challenging to implant in the subcoronary position. METHODS: All consecutive patients who underwent a bioprosthetic aortic valve replacement (AVR) were included from our institutional database. Cox regression analysis was preformed to determine significant predictors for mid term mortality as well as all cause, cardiac, and heart failure readmission. RESULTS: Patients in the subcoronary stentless group were older and more likely to be female and were likely to have a higher Society of Thoracic Surgery risk of mortality. Survival was superior in the stented AVR cohort at 30-days (96.4% vs 90.5%; P < .001), 1-year (90.5% vs 71.6%; P < .001), and 5-year (74.5% vs 56.9%; P < .001) follow up. Acute kidney injury (16.22% vs 5.22%; P < .001) and blood product transfusion (70.27% vs 44.0%; P < .001) were higher in the stentless group. Multivariable analysis revealed subcoronary stentless implantation as a significant independent risk factor for mortality (hazards ratio: 1.92 [1.35,2.72]; P < .001). CONCLUSION: Stentless porcine xenograft implantation with the Freestyle bioprosthetic in the subcoronary position can be successfully performed in select patients, but its use is associated with increased perioperative morbidity and mortality affecting midterm outcomes. Individual patient selection and surgeon experience are important to ensure favorable outcomes.

Solo Smart stentless bioprosthesis for extensive aortic annular defects caused by infective endocarditis.

BACKGROUND AND AIMS: The optimal valve and prosthesis in patients with aortic valve infective endocarditis with annular abscess is controversial. If extensive annular defects occur after debridement, standard techniques are difficult; more complex aortic root replacement (ARR) or aortic valve translocation technique are inevitable. The Solo Smart stentless bioprosthesis is specially designed for supra-annular implantation without annular stitches. METHODS: Nineteen patients with active aortic valve infective endocarditis underwent aortic valve replacement in the past 3 years. Of these, we performed aortic valve replacement using the Solo Smart valve in four patients with extensive annular destruction and complex aortic root pathologies requiring reconstruction. RESULTS: Although more than two-thirds of the annular structure was missing after radical debridement of infected tissues, supra-annular aortic valve replacement with the Solo Smart valve could be performed successfully in all four patients. All patients are doing well without prosthetic valve dysfunction and/or recurrent infection. CONCLUSION: The supra-annular aortic valve replacement using the Solo Smart valve is considered to be a useful alternative to standard aortic valve replacement in patients complicated with extensive annular defect. It is a simple and technically less demanding alternative to ARR or aortic valve translocation technique.

Gerbode defect and left ventricular-aortic discontinuity in prosthetic valve endocarditis.

Communication between the left ventricle and right atrium is known as the Gerbode defect. The defect is usually congenital but can be acquired secondary to infective endocarditis. Left ventricular-aortic discontinuity is another serious complication of extensive infective endocarditis. Here, we report a rare case of prosthetic valve endocarditis complicated with both acquired Gerbode defect and left ventricular-aortic discontinuity. We successfully performed reconstructive surgery involving patch closure of the Gerbode defect and reconstruction of the circumferential left ventricular outflow tract with a xenopericardial patch, followed by supra-annular aortic valve replacement with the Solo Smart bovine pericardial stentless valve.

Surgical treatment for left ventricular-aortic discontinuity and Gerbode defect with endocarditis.

An extensive infection of the native aortic or prosthetic valve beyond the aortic annulus could be complicated with various types and degrees of tissue destruction. The left ventricular-aortic discontinuity resulting from extensive infective endocarditis often necessitates pericardial reconstruction of the left ventricular outflow tract and subsequent aortic root replacement. Furthermore, if the membranous ventricular septum is involved with infective tissue destruction, communication between the left ventricle and right atrium, known as a Gerbode defect, and complete atrioventricular block could occur. Surgical reconstruction of these complex pathologies is challenging, with high mortality and morbidity. Herein, we present a rare case of prosthetic valve endocarditis complicated with both left ventricular-aortic discontinuity and an acquired Gerbode defect. At the time of surgery, left ventricular outflow tract reconstruction and the technically more demanding aortic root replacement were considered inevitable because of extensive tissue destruction. However, we performed circumferential left ventricular outflow tract reconstruction with a xenopericardial patch and supra-annular aortic valve replacement using the Solo Smart bovine pericardial stentless valve as a technically less demanding alternative to aortic root replacement. The postoperative course was uneventful, and the patient is well 1 year postoperatively, without valvular dysfunction and recurrent infection.

Surgical case of isolated pulmonary valve endocarditis in a patient without predisposing factors.

We report a case of isolated pulmonary valve endocarditis in a 47-year-old woman without predisposing factors. She had episodes of low-grade fever and non-productive cough and was initially diagnosed with bacterial pneumonia. With antibiotic treatment, her condition improved transiently, but she had repeated respiratory events. Forty days after her first visit, she complained of severe dyspnea. Echocardiography revealed a large vegetation adhering to the pulmonary valve and she was diagnosed with isolated pulmonary valve endocarditis. Surgical treatment was selected because antibiotic treatment was not effective. The main pulmonary artery was transected above the annulus and the infected valve was excised. To avoid contact of the prosthetic valve with the infected pulmonary annulus, a stentless bioprosthesis was interposed between the transected parts of the pulmonary trunk. Two years after the surgery, the patient is stable with no sign of infection.

Successful Stentless Aortic Valve Replacement Navigated by VR Images in a Case of Bicuspid Aortic Stenosis with Valsalva Sinus Asymmetry / 日本心臓血管外科学会雑誌

SOLO SMART is a stentless bioprosthesis that comprises a larger effective orifice area and reduced pressure gradient, exhibiting a better hemodynamic profile than a stented bioprostheses. Currently, SOLO SMART finds application in patients with aortic valve diseases. However, patients with bicuspid aortic valve disease may present Valsalva sinus asymmetry. Recently, some studies have considered SOLO bioprosthesis as contraindicated in patients with a bicuspid aortic valve. Here, we report the case of a 79-year-old female with bicuspid aortic stenosis and Valsalva sinus asymmetry. We preoperatively assessed the aortic root of the patient using a novel 3D workstation that creates virtual reality (VR) images from cardiac CT data. After creating three symmetric commissures at the wall of the Valsalva sinus, we evaluated the distance from the coronary orifices. We determined the appropriate suture line of bioprosthesis avoid coronary orifice occlusion. Aortic valve replacement with SOLO SMART was successful, and the postoperative clinical course was uneventful. Hence, preoperative evaluation of the aortic root using VR images could be a precise and useful method for the assessment of the operative indication for SOLO SMART.

A propensity matched analysis of outcomes and long term survival in stented versus stentless valves.

BACKGROUND: To compare the perioperative and long term survival after aortic valve replacement using stentless versus stented valves in a large cohort of patients grouped using propensity score matching. METHODS: From 1991 to 2012, 4,563 patients underwent aortic valve replacement with stentless and stented valves at our institution. Propensity score matching identified 444 pairs using 13 independent variables: incidence of operation, smoking status, renal failure, hypertension, diabetes, peripheral vascular disease, cerebrovascular disease, chronic lung disease, ejection fraction, gender, age, valve status, and use of coronary artery bypass graft. Data were collected from our Society of Thoracic Surgeons database and the Social Security Death Index. Groups were compared using univariate and Kaplan-Meier analysis. RESULTS: The two groups demonstrated no significant differences for the 13 matching variables and the majority of 30-day outcomes (p > 0.05). The stented valve group showed a higher incidence of postoperative bleeding (3.6% vs 1.1%, p = 0.015), but a lower incidence of stroke (0.9% vs. 2.9%, p = 0.028). One, five, and 10-year survival was 95.0, 80.7, and 52.8% for stented and 93.2, 80.5, and 51.3% for stentless valves. Overall survival did not differ significantly between the two groups (p = 0.641). CONCLUSIONS: Stentless and stented valves had identical 30-day outcomes except for a higher postoperative incidence of bleeding and a lower incidence of stroke in the stented group. There was no significant difference in long term survival between valve types. Both valves may be used for aortic valve replacement with low morbidity and excellent long term survival.

Fungal native pulmonary valve endocarditis: facing both medical and surgical challenges.

Fungal isolated native pulmonary valve endocarditis is extremely uncommon. Data are scarce and report high mortality and recurrence rates. Recommended management combines both medical and surgical approaches. We report herein a rare case of isolated pulmonary valve endocarditis caused by Candida albicans The patient did not display prior heart disease. Medical management was unsuccessful. Pulmonary valve replacement allowed rapid improvement.

Stentless bioprostheses: a versatile and durable solution in extensive aortic valve endocarditis.

OBJECTIVES: Infective endocarditis of the aortic valve with local aortic root destruction requires radical resection of infected tissues and subsequent reconstruction of periannular structures and the left ventricular outflow tract (LVOT). Homografts or stentless bioprostheses are recommended for use in this specific patient group. The Freestyle stentless bioprosthesis is a porcine aortic root prosthesis, which approaches the surgical versatility of the homograft, but has the advantage of ready availability and uniform quality. We assessed clinical and echocardiographic outcome following the use of this prosthesis in extensive aortic valve endocarditis. METHODS: Between June 2000 and December 2014, 55 Freestyle prostheses were implanted for aortic valve endocarditis involving the root in 54 patients (74% male). The mean age at operation was 61 ± 13 years. The mean EuroSCORE II was 20.1 ± 13.5. Twenty-nine (54%) patients had prosthetic valve endocarditis. The median follow-up time after surgery was 3.5 years, ranging from 0 to 15 years. RESULTS: Early and late mortality were 11% (6 patients) and 14% (7 patients), respectively. Estimated overall survival at 1 and 5 years was 83 and 70%, respectively. There was no survival difference between patients with native or prosthetic valve endocarditis. One patient underwent reoperation for recurrent endocarditis 2.3 years after the initial procedure. No other prosthesis failure occurred. At a median follow-up of 3.3 years, mean gradient over the prosthesis was 4.3 ± 2.3 mmHg. No patient had more than mild aortic regurgitation. CONCLUSIONS: The Freestyle stentless bioprosthesis is a valuable option to reconstruct the LVOT after debridement in extensive aortic valve endocarditis. It is readily available with a versatility and clinical outcome comparable with that of homografts. Although early mortality remains considerable in this high-risk group of patients, late survival is good with low rates of recurrence of endocarditis, immediate local control and good haemodynamic performance on echocardiography.

Stentless vs Stented Aortic Valve Bioprostheses in the Small Aortic Root.

In patients with a small aortic root undergoing aortic valve replacement (AVR), the Freedom SOLO bioprosthesis may be the ideal prosthesis because of its stentless design and supra-annular implantation. This study investigated if the stentless Freedom SOLO has an advantage when compared with a stented bioprosthesis in patients with a small aortic root. From April 2005-July 2014, 269 consecutive patients underwent AVR with either a Freedom SOLO (n = 76) or Mitroflow (n = 193) bioprosthesis size 19mm or 21mm, respectively. This retrospective comparison study presents clinical and echocardiographic follow-up data. In results, operative outcome and survival were similar. At 7 years, cumulative incidence of aortic valve reoperation and structural valve deterioration favor the Freedom SOLO (0% vs 7.1%, P = 0.03 and 0% vs 4.5%, P = 0.08, respectively). Additionally, the postoperative peak and mean valvular gradients favor the Freedom SOLO (21 ± 9mmHg vs 32 ± 12mmHg and 12 ± 5mmHg vs 19 ± 8mmHg, both P = <0.001, respectively). During mid-term follow-up this hemodynamic advantage continued in favor of the Freedom SOLO. Also prosthesis-patient mismatch occurred less frequently in the Freedom SOLO (28% vs 52%, P = 0.001). There were no differences in prosthetic valve endocarditis, thromboembolic, or bleeding events. In conclusion, the stentless Freedom SOLO has several significant advantages for AVR in patients with a small aortic root in comparison with a stented Mitroflow bioprosthesis. The Freedom SOLO shows superior hemodynamic performance with significantly lower valvular gradients that remained stable during mid-term follow-up. Additionally, significantly fewer prosthesis-patient mismatch occurred and the Freedom SOLO showed superior durability.

North American trial results at 1 year with the Sorin Freedom SOLO pericardial aortic valve.

OBJECTIVES: A North American prospective, 15-centre Food and Drug Administration (FDA) valve trial was designed to assess the safety and effectiveness of the Freedom SOLO stentless pericardial aortic valve in the treatment of surgical aortic valve disease. METHODS: Beginning in 2010, 251 patients (mean: 74.7 ± 7.5 years), were recruited in the Freedom SOLO aortic valve trial. One hundred eighty-nine patients have been followed for at least 1 year and are the basis for this review. Preoperatively, 54% of patients had NYHA functional class III or IV symptoms, and the majority of patients had a normal ejection fraction (EF) (median EF = 61%). Concomitant procedures were performed in 61.9% of patients, with coronary artery bypass grafting (CABG) (48.7%) being the most common followed by a MAZE procedure (13.7%). Reoperations were performed in 8.5% of patients in the study. RESULTS: The entire cohort of 251 patients enrolled had 7 deaths prior to 30 days, 2 of which were valve-related (aspiration pneumonia and sudden death) and 5 were not valve-related. There were 11 deaths after 30 days, 1 valve-related (unknown cardiac death) and 10 not valve-related. Five valves were explanted, 3 early (endocarditis, acute insufficiency and possible root dissection) and 2 late (endocarditis). Thirty-day adverse events include arrhythmias requiring permanent pacemaker (4.2%), thromboembolic events (3.7%) and thrombocytopenia (7.4%). One-year follow-up of all 189 patients demonstrated mean gradients for valve sizes 19, 21, 23, 25 and 27 mm of 11.7, 7.8, 6.3, 4.6 and 5.0 mmHg, respectively. Effective orifice areas for the same valve sizes were 1.2, 1.3, 1.6, 1.8 and 1.9 cm(2), respectively. Ninety-six percent of patients (181/189) were in NYHA class I or II at the 1-year follow-up. CONCLUSIONS: The Freedom SOLO stentless pericardial aortic valve demonstrated excellent haemodynamics and a good safety profile out to the 1 year of follow-up.

Valve-in-valve transcatheter aortic valve implantation for failing surgical aortic stentless bioprosthetic valves: A single-center experience.

BACKGROUND: Valve-in-valve (ViV) transcatheter aortic implantation (TAVI) is an alternative to redo surgery for patients with a failing aortic bioprosthesis. A lack of anatomic markers may complicate the procedure. This study reports procedural and midterm outcomes of patients undergoing ViV-TAVI for failing stentless bioprostheses, at a single institution. METHODS: A total of 22 consecutive patients with failing homograft (n = 17), stented porcine valve (n = 3), aortic root bioprosthesis (n = 1), or native resuspended aortic valve (n = 1) (aged 74 ± 12 years; Society of Thoracic Surgeons 30-day predicted risk of mortality score: 14% ± 8%) were treated with ViV-TAVI, between 2007 and 2014. All had severe aortic regurgitation and were highly symptomatic before TAVI: 41% had chronic kidney disease; 32% had undergone previous coronary bypass grafts; 27% had previous percutaneous coronary intervention; 14% had severe pulmonary disease; 14% had had a stroke. All underwent TAVI with a self-expanding device. RESULTS: The 30-day mortality was 0%. No cases occurred of myocardial infarction, tamponade, stroke, severe bleeding, acute kidney injury, or major vascular complications. Three instances of device migration, and 1 of device embolization, occurred. Permanent pacing was required in 14%. Paravalvular aortic regurgitation was absent or mild in 19, and mild to moderate in 3. Average hospital stay was 8 ± 3 days; all patients were discharged home. Six-month and 1-year mortality was 4.8% and 14.3%, respectively. Aortic valve area and paravalvular aortic regurgitation were unchanged at 1 year. CONCLUSIONS: The ViV-TAVI procedure may be performed in high-risk patients with a degenerate stentless bioprosthesis with low 30-day mortality, and 1-year mortality of 14.3%. Although technically challenging, owing to a lack of anatomic markers, satisfactory positioning is possible in most cases, with excellent clinical and echocardiographic outcomes.

Clinical and haemodynamic outcomes in 804 patients receiving the Freedom SOLO stentless aortic valve: results from an international prospective multicentre study.

OBJECTIVES: The Freedom SOLO™ valve (Sorin Group, Italy) is a stentless aortic bioprosthesis designed for simplified implantation. The present multicentre study is the largest prospective evaluation of this prosthesis. Herein, we report on outcomes at 3-year follow-up. METHODS: From March 2009 to February 2013, a total of 804 consecutive patients (mean age 74.9 ± 6.3 years; 45.1% females) underwent aortic valve replacement with the Freedom SOLO™ valve at 33 centres. Concomitant procedures (70.2% coronary artery bypass grafting) were performed in 376 patients. The cumulative follow-up included 1100 patient-years (mean 16.5 ± 10.8 months; range: 0-40.5 months). RESULTS: Sixty-four patients died (14 early, 50 late); 12 deaths (1 early, 11 late) were valve-related. Operative mortality (30 days) was 1.7%. At 3 years, overall survival was 82.6% [95% confidence interval (CI) 75.5-87.8%] and freedom from valve-related death was 95.5% (95% CI 89.2-98.2%). Linearized late event rates were 0.82%/patient-years for non-structural valve dysfunction, 0.55%/patient-years for structural valve deterioration, 1.55%/patient-years for endocarditis, 3.64%/patient-years for thromboembolism and 3.18%/patient-years for bleeding. In total, there were 22 reinterventions [19 valve explants, 2 refixations, 1 transcatheter aortic valve intervention (TAVI)] for endocarditis (11), non-structural dysfunction (9) and structural valve deterioration (2). Freedom from reintervention was 95.2% (95% CI 91.2-97.4%) at 3 years. There were no instances of valve thrombosis or haemolysis. At 1, 2 and 3 years, 97.0, 95.5 and 91.4% of patients were in NYHA class I or II. Between discharge and 3 years after surgery, mean transvalvular gradients exhibited a non-significant increase (6.5 ± 4.3 vs 8.7 ± 6.5 mmHg), whereas effective orifice area index remained stable (0.9 ± 0.2 vs 0.8 ± 0.3 cm(2)/m(2)). At 3 years, no patient presented with more than mild aortic regurgitation. Left ventricular mass index decreased significantly between discharge and 1 year after surgery (139.4 ± 40.9 vs 122.4 ± 35.3 g/m(2), P < 0.001) and remained unchanged thereafter. Left ventricular size and function did not change over time. CONCLUSIONS: The Freedom SOLO™ valve is a unique stentless pericardial bioprosthesis whose design favours haemodynamic performance and thus facilitates left ventricular reverse remodelling. In terms of survival, morbidity and functional status, it is associated with beneficial outcomes up to 3 years after surgery. Ongoing follow-up will assess the valve at the long-term course.

Reoperation for Rupture of the Porcine Aortic Wall of a Stentless Bioprosthesis / 日本心臓血管外科学会雑誌

A 63-year-old woman presented with pseudoaneurysm formation due to rupture of the porcine aortic wall of the stentless bioprosthesis. She had undergone aortic root replacement using the full root technique with the 25-mm Prima Plus bioprosthesis for annuloaortic ectasia. Congestive heart failure, appearing 65 months after the first surgery, progressed rapidly. Multidetector computed tomography (CT) showed a pseudoaneurysm of the aortic root, and echocardiography revealed severe mitral regurgitation. At reoperation, a large pseudoaneurysm with a 20-mm horizontal tear was seen in the non-coronary sinus of the Prima Plus valve. A repeat aortic root replacement and mitral valve replacement with two mechanical valves were performed. The patient had an uneventful recovery. Histologic examination of the explanted porcine aortic root showed host mononuclear cells and macrophages between the well-stained and poorly stained areas, suggesting that the torn tissue had undergone host-mediated degeneration to some extent. Porcine aortic roots have excellent hemodynamic features, but ruptures in the aortic sinuses of the porcine aortic root have been reported in some cases. Careful follow up with CT or echocardiography is therefore needed after aortic root replacement with stentless bioprostheses.

Stentless xenografts as an alternative to pulmonary homografts in the Ross operation.

OBJECTIVES: Because of the limited availability of pulmonary homografts (PH), porcine stentless xenografts (SX) have been proposed as an alternative for pulmonary valve replacement in the Ross operation. However, it is unknown whether they have similar good long-term durability. Therefore, we compared mid- to long-term outcomes between those two right ventricular outflow tract (RVOT) substitutes. METHODS: In 288 adults (>18 years) undergoing a Ross operation between 1991 and 2012, Freestyle(®) SX was used in 18 patients and a cryopreserved PH was used in 270 for RVOT reconstruction. Only patients with follow-up >2 years were included. According to the operative period, gender and age, 37 patients with PH could be matched with 17 SX patients. Clinical and echocardiographic follow-up were obtained. In a subset of patients (SX, n = 11 and PH, n = 25), a cardiac computed tomographic (CT) scan was performed to analyse graft calcification. RESULTS: The mean follow-up period was 8.2 ± 4.0 (range 2-14.6 years). During this period, 3 patients died from cancer, 2 in the SX group and 1 in the PH group (P = 0.15). No patient needed RVOT reoperation. At follow-up, RVOT peak gradient was 21 ± 5.9 mmHg in the SX and 16.3 ± 8.7 in the PH groups (P = 0.07). Peak gradient >40 mmHg was observed in only 1 patient in the PH group. Mean RVOT regurgitation was 0.1 ± 0.4 in the SX group and 0.8 ± 0.6 in the PH group (P = 0.008). CT scan analyses showed progressive calcification mainly of the graft wall, while the valve remained relatively free of calcium. Patients with the SX presented significantly higher calcium scores than those with PH (P = 0.01). CONCLUSIONS: In adult patients having the Ross operation, calcic degeneration is observed in both the PH and the SX used as pulmonary substitutes. Calcification progresses more rapidly in the SX compared with the PH. In both grafts, calcifications affect mainly the wall, while the valve remains relatively free of calcium. As a consequence, both grafts show good and similar haemodynamic outcomes at mid- to long-term follow-up. The Freestyle(®) SX can be considered as an acceptable alternative for RVOT reconstruction when PH is not available.