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 valve in re-replacements and acute aortic valve endocarditis.

Between June 1990 and June 1993, 135 patients received a porcine stentless aortic valve (PSAV) at our institution. In this group, there were 33 patients in whom the stentless valve was used to replace a previously inserted malfunctioning aortic valve prosthesis (n = 19) or to treat acute aortic valve endocarditis (n = 14, five native, nine prosthetic endocarditis). There was one hospital death caused by multiple organ failure in a patient with endocarditis and preoperative cerebral stroke. Two patients died after hospital discharge; one suffered sudden death following a pacemaker failure four month after surgery and the other died due to Candida albicans sepsis after a prolonged antibiotic treatment. There were two reoperations; one to correct a dehiscence of the proximal suture line and the other to replace a degenerated valve 3.5 years after implantation in a 14 year old boy. All operative survivors were followed clinically with serial color Doppler echocardiography. No recurrence of endocarditis was detected. Aortic root reconstruction was achieved even in the presence of multiple abscesses. All but one patients showed a normally functioning valve with none or minimal aortic insufficiency. In our opinion the PSAV is an excellent aortic valve substitute for patients with damaged aortic annulus, because it promotes aortic root remodeling, decreases the incidence of postoperative paravalvular leaks and helps to prevent endocarditis recurrence.

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)

The new stentless aortic valve: clinical results of the first 100 patients.

From May 1990 to August 1993, 100 patients underwent aortic valve replacement using the stentless porcine aortic valve. There were 69 males and 31 females. The mean age was 36 (range 11-76) years. Of 70 patients under 40 years of age, 20 were less than 20 years old. Indications included rheumatic heart sequelae in 55 patients (first valve replacement), prosthetic failure in 20, endocarditis in 13, congenital aortic bicuspid valve in four, degenerative disease in four and senile calcified aortic valves in four. Twenty patients had aortic annular related pathology. There were 15 associated surgical procedures. Forty-three patients required aortic root enlargement. There were approximately equal numbers of patients in New York Heart Association (NYHA) functional classes III and IV. The hospital mortality rate was 6%; 14 patients who experienced hospital morbidity had a full recovery. Two late reoperations were performed in patients with primary valve endocarditis; their recovery was uneventful. Four late deaths were not valve related. Comparative echo Doppler analysis before and after operation demonstrated good improvement of left ventricular function in nearly all patients. The valve was competent in 96% of patients and the remainder displayed minor jets without haemodynamic significance. The valve coaptation was stable in all patients. Use of the stentless porcine aortic valve in this first 100 patients has provided excellent clinical results with a follow-up of 41 months. Further follow-up and close observation will be required to analyse the outcome of this new valve and procedure with time.