Retrospective clinical analysis of stented vs. stentless porcine aortic bioprostheses.

OBJECTIVE: The study was designed to compare hemodynamic performance, structural failure and survival of patients undergoing aortic valve replacement (AVR) with a composite aortic stented or stentless porcine bioprosthesis. METHODS: From January 1990 to June 1999, the clinical data of 725 patients undergoing AVR with stented porcine aortic bioprosthesis were reviewed. We defined two groups of patients with similar clinical characteristics: 202 patients receiving aortic stented and 205 patients stentless valves. The two patients groups were similar in age, sex, valve lesion, valve size, preoperative New York Heart Association (NYHA) class status and follow-up. RESULTS: The number of patients available for follow-up, excluding hospital and late mortality, reoperations and patients lost to follow-up, was 157 for the stented and 175 for the stentless group. There was a higher incidence of rheumatic heart disease in the stented (59%) vs. stentless group (44%), (P=0.003). Fewer patients had prior aortic bioprosthetic dysfunction in the stented (7.6%) compared to the stentless group (25%) (P<0.001). The mean intensive care unit stay, hospital mortality and late mortality were similar (P, NS). The total complication rate was higher in the stented (12%) than the stentless (3.4%)(P=0.005). Valve related death was higher in the stented (2.5%) than the stentless (0%) (P=0. 049). Postoperatively, the aortic effective orifice area (AEOA) was larger (P<0.001) and the transvalvular peak and mean gradients were lower in the stentless group (P<0.001). The leaflet tissue degeneration analysis was 8.0% in patients at risk for stented and 0. 6% for stentless (P=0.001). Actuarial analysis disclosed no statistical difference in patient survival between groups (P=0.18). Reoperations were less frequent in the stentless group (P=0.010). CONCLUSIONS: Hemodynamic benefits in the stentless group were evident and expressed by larger AEOA, lower gradients, better left ventricular remodeling with significant decrease of the left ventricular mass. Lower complication rates, lower reoperation rates, less leaflet tissue degeneration, and lower valve related mortality rates were seen in the stentless group. A controlled clinical comparison trial with longer follow-up will be required to confirm these clinical and hemodynamic benefits.

Use of bovine pericardial tissue for aortic valve and aortic root replacement: long-term results.

BACKGROUND AND AIMS OF THE STUDY: The study aimed to determine the clinical performance of bovine pericardial aldehyde-treated products alone or in combination with aortic leaflets of porcine origin. These included a composite porcine stentless aortic valve attached to a scalloped pericardial tube (BSAV), and valved and non-valved bovine pericardial conduits for use in left-sided heart lesions (BPG). METHODS: For BSAV grafts, between January 1990 and August 1996, 163 patients (119 males) had their aortic valves replaced by SJM Biocor BASV. Mean age was 37.9 +/- 17.6 years (range: 1 to 76 years). Rheumatic heart disease sequelae (n = 72) and replacement of a prosthetic heart valve (n = 46) were predominant. Preoperative NYHA functional class showed 90 patients (55.2%) in class III and 50 (30.7%) in class IV. BPVC and NVPC grafts were used in 166 patients: acute aortic dissection was the main indication in 52 (31.3%) and chronic in 36 (21/7%). The ascending aorta was involved in 141 patients (84.9%); grafts were seldom used at other sites. In most patients the graft implanted was either a non-valved (n = 79) or a valved (n = 75) pericardial conduit. Twelve patients had a localized lesion and required a patch repair. RESULTS: For BASV grafts, the non-valve-related hospital mortality rate was 4.9%. There were 14.7% non-fatal complications with full recovery of all patients. Mean follow up in 141 patients was 3.0 +/- 1.4 years (range: 1 month to 7.2 years); 14 patients were lost to follow up. Late, non-conduit-related, mortality occurred in seven patients (4.9%). Eight patients underwent reoperation. The current clinical follow up of 127 patients has shown 118 (92.9%) with competent valves and nine (7.0%) with mild stable aortic insufficiency. For BPVC and NVPC grafts, hospital mortality rate was 16.9%, death being related to poor preoperative clinical condition. Postoperative follow up was accomplished in 125 patients; reoperation was necessary in seven patients. Histology showed good tissue preservation up to five years; echocardiography revealed satisfactory findings. No valved conduit had to be reoperated for valve or pericardial tissue wear. CONCLUSIONS: Clinical results of left-sided heterologous pericardial grafts have shown excellent performance over time. The BASV (over seven years) and BPVC and NVPC (eight years) have demonstrated superior results as aortic valves alone or in combination with a pericardial conduit.

The use of bovine pericardium for pulmonary valve reconstruction or conduit replacement: long-term clinical follow up.

BACKGROUND AND AIMS OF THE STUDY: This study aimed to determine the clinical performance of bovine pericardial aldehyde-treated material alone or in combination with aortic leaflets of porcine origin. These were the porcine aortic stentless pulmonary valved bovine pericardial conduit (PSPVC), and porcine aortic monocusp attached to pericardial patch (PAMC), used to correct right-sided heart lesions. METHODS: Between November 1985 and October 1995, 33 patients underwent corrective congenital surgery with PSPVC. Mean patient age was 5.7+/-4.3 years (range: 15 days to 18 years). Pulmonary atresia with ventricular septal defect (VSD) was the most frequent disease (16/33, 48%). For PAMC, 45 patients with various congenital heart malformations underwent implantation between June 1989 and April 1996. Mean patient age was 4.8+/-4.7 years (range: 2 weeks to 18 years). RESULTS: With PSPVC, hospital mortality rate was 18.2% and related to poor preoperative clinical condition in six cases. Four patients were lost to follow up; 23 (85%) were followed for 3 months to 10 years (mean 4.8+/-3.0 years). Distal anastomotic scarring in four patients was probably due to retraction of the pericardial tissue. With PAMC, hospital mortality rate was 11% and related to patients' preoperative clinical condition. Three patients were lost to follow up; 37 survivors have been followed for 6 to 88 months (mean 38.5+/-19.0 months). There were no late deaths. Two patients underwent reoperation; intra-operative observation showed well-preserved monocusps with no signs of tissue degeneration. The remaining 35 patients remain asymptomatic by clinical examination and Doppler echocardiography. The monocusps remained mobile in every case. CONCLUSION: PSPVCs have shown excellent performance and durability in young patients with a low mean age (5 years). The monocusp graft has remained functional with good leaflet motion for up to seven years.

Porcine stentless valve/bovine pericardial conduit for right ventricle to pulmonary artery.

BACKGROUND AND OBJECTIVES: We assessed the long-term outcome of a glutaraldehyde-preserved bovine pericardial conduit containing a stentless composite porcine aortic valve. METHODS: Between November 1985 and May 1995, 33 stentless porcine valves attached to bovine pericardial conduits were used in 33 patients with complex congenital cardiac malformations. These patients required a conduit between the right ventricle and the pulmonary artery because of an absent or inadequate pulmonic artery. All patients were approached by midsternotomy. One patient with pulmonic atresia and an interventricular septal defect required left thoracotomy for ligation of collaterals. RESULTS: Of the initial 33 patients, clinical follow-up was performed in 23 discharged patients (70%) for 1.7 to 10.5 years. The echo-Doppler analysis performed in each of the 23 followed patients showed excellent conduit and valve function in all but 4 patients, in whom a valve gradient of 60 mm Hg was noted. There was no tissue structural failure noticed in this study. CONCLUSIONS: The SJM Biocor (Belo Horizonte, Brazil) bovine pericardial stentless valved conduit performed well as a substitute for the right ventricle to pulmonary artery connection.

Porcine mitral stentless valve mid-term clinical results.

OBJECTIVES: Time testing is essential with any valvular procedure, especially when a new concept is introduced such as the mitral stentless valve. Our purpose is to evaluate the results obtained over 4 years with this operation, particularly to attest the impact of preservation of annulo ventricular continuity on the long term results of these patients. METHODS: From March 1992 to August 1996, 120 patients had their mitral valves replaced with a porcine stentless mitral valve. The observation period was 54 months with total patients follow-up of 3424 months with a mean of 28.5 months. The age ranged from 11 to 72 years (mean 35.22 +/- 14.98). There were 73 females (60.8%) and 47 males (39.2%). The predominant etiology was rheumatic heart disease. Associated procedures were performed in 12 patients (10%), and the great majority of the patients were in functional class III and IV (NYHA). RESULTS: Hospital mortality occurred in seven patients (5.83%) non valve related except for one early case of endocarditis. Early reoperation related to technical failure were necessary in 4 patients without mortality. Follow-up was accomplished in 101 patients and ranged from 2 to 54 months. Late reoperations were required in 16 patients (nine due to mitral insufficiency, five because of endocarditis and two for mitral stenosis). Most reoperations were related to technical failure. Among the 82 patients presently in control, 72 showed a competent mitral stentless valve, eight with stable mild mitral regurgitation and in two a decreased mitral orifice. Hemodynamic performance of the valve has been excellent in this group, particularly in patients with left ventricular dysfunction. CONCLUSION: Although technical complexity remains the main cause of reoperations with this valve, experience has shown that it not only provides preservation of the left ventricular function but also promised significant increase of the ejection fraction in patients with poor left ventricular function.

Surgical technique of implanting the stentless porcine mitral valve.

The new stentless porcine mitral valve was developed to serve as an anatomically correct substitute for a diseased mitral valve. Extensive acute animal experimentation was performed, and from this the logical sequence for selecting the correct valve size and the specific technique for implanting it were determined. The following are the major steps to successfully implant a mitral stentless valve: First, mitral valve complex analysis must be done to determine the correct procedure to be performed and the feasibility of using the stentless mitral valve. Second, the correct size of stentless mitral valve must be chosen. Third, the papillary muscle anatomy must be assessed to determine the site and number of sutures necessary for securely holding the new origin of the new chordae. Fourth, the papillary muscle sutures must be anchored to the free pericardial edge of the new chordal origin. Fifth, the chordal alignment with both trigonal areas must be perfect. Sixth, the annulus may be sutured using either continuous or interrupted sutures. Perioperative echocardiography, preferably transesophageal echocardiography, should be done in every patient. Although reoperation was necessary in 5 patients (non-valve-related), the results in 74 patients (3 early and 3 late non-valve-related deaths excluded) followed up for at most 26 months (mean, 14 months) have been excellent. The quality of the results obtained in this initial clinical trial has reinforced our current preference for this valve in patients requiring mitral valve replacement. Longer follow-up is required to confirm that these good results continue.

Porcine stentless aortic heart valve substitute mid-term clinical follow-up.

From May 1990 to January 1994, 120 patients underwent aortic valve replacement with the use of the Biocor porcine aortic stentless heart valve (BPASHV). There were 83 male and 3 female patients. The age ranged from 11 seventy-six (76) years with a mean of 36. Eighty-five patients were under 40 years of age. Sixty-four patients underwent their first aortic valve replacement due to rheumatic heart disease, 30 because of prosthetic valve failure and of those: 20 were due to primary tissue failure and in 10 due to prosthetic endocarditis, native aortic bicuspid valve in 11 and senile calcificant aortic valve disease in four. Thirty-three patients had aortic annular related pathology. Their preoperative functional class revealed 61 patients in class III and 59 in class IV. The longest follow-up in this aortic group was 42 months with a mean of 26. The surgical technique used rendered consistent and reproducible results. There was a hospital mortality of six patients (5%). The mortality was not valve related. The hospital morbidity in 14 revealed full recovery of all patients. There were four late reoperations, in two due to recurrent endocarditis and in the last two because of paravalvar leak. There was a late mortality of four patients (non valve related). The follow-up of these patients revealed full competent aortic stentless valve in 97 patients and only minor jet in nine. Most patients are in functional class I and II. The Aortic stentless concept has proven to be outstanding with the use of the Biocor Aortic stentless valve throughout the current follow-up.(ABSTRACT TRUNCATED AT 250 WORDS)

Porcine stentless mitral heart valve substitute: short term clinical data.

Beginning March 1992 to February 1994, 65 patients were submitted to mitral valve replacement using the porcine mitral stentless heart valve. This group took in 65 patients, their age ranged from four to 65 with a mean of 26 years. Forty patients were below years of age. The major indication was rheumatic heart disease sequelae in 50 patients, mitral valve endocarditis in six, myomatous degeneration in four and in five previous mitral prosthetic valve was replaced due to tissue failure. The preoperative functional class revealed 35 patients in class III and 30 in class IV. The longest follow-up was 23 months with a mean of 12. The surgical technique used rendered consistent and reproducible results. There was a hospital mortality of two patients or 3.1%. The hospital morbidity revealed full recovery of all patients. There were three patients reoperated because of valve endocarditis in two and in one due to partial dehiscence of the suture at the annular level. All three patients had full recovery after a reoperation. There was a late mortality of two patients, non valve related. The follow-up of these patients revealed full competent stentless mitral valve in 50 patients and in nine minor to mild jets were encountered by color echo-Doppler. Most patients are in functional class I and II. The stenless concept has prove to be outstanding in the mitral position throughout the current follow-up of close to 2 years.(ABSTRACT TRUNCATED AT 250 WORDS)