Lorenzo Gonzalez-Lavin

Iatrogenic left ventricular—right atrial fistula following mitral valve replacement

A case of an acquired left ventricular-right atrial fistula complicating Starr-Edwards replacement of a non-calcific mitral valve is reported. Emphasis is placed on the diagnostic methods and the anatomical relationship of the mitral valve to the atrioventricular septum. Surgical repair is advocated as soon as this complication of mitral valve replacement is discovered.

Long-term Results After Aortic Valve Replacement with Preserved Aortic Homografts

Abstract Two hundred fifty-nine patients have undergone aortic valve replacement with preserved homograft valves. The total hospital mortality was 16.6%, declining to 4.8% for the years 1968 and 1969. Patients discharged from the hospital have been followed from one and one-half to seven and onehalf years. Of these patients, 71.2% retain the original homograft valve at the time of this analysis. Eighty-five patients have no diastolic murmur, and 38 have trivial aortic regurgitation characterized only by a soft, short diastolic murmur. Valve failure has occurred in 46 of the 259 patients. Degenerative changes such as cusp rupture and calcification were responsible for 28 failures; all may be due to the methods of valve sterilization and preservation. Late mortality related to valve failure was 5.4%. Homograft valves sterilized by antibiotics are now used in an attempt to avoid degenerative changes by implanting a fresh and viable valve. This recent experience is presented, and early results are promising.

Viability of fresh aortic valve homografts: a quantitative assessment

Accumulated evidence indicates that fresh aortic valve homografts function longer than preserved grafts. Thus it becomes important to assess the viability of fresh homografts on a quantitative basis. Recently, we have used autoradiography in addition to tissue culture to determine the viability of fresh aortic and pulmonary valve homografts. The uptake of thymidine was gradually reduced to 50% after 18 days of preservation in a balanced salt solution with antibiotics and the uptake was reduced to 21% in 63 days. We think that a nutrient medium is necessary if longer viability is to be obtained.

Left Ventricular Wall Rupture after Mitral Valve Replacement: Report of Successful Repair in 2 Patients

Left ventricular wall rupture after mitral valve replacement, though uncommon, is a disastrous complication when it does occur. We have experienced this problem in 2 separate instances. Successful treatment was accomplished by suturing a large prosthetic patch over the entire area of laceration and hematoma.

Surgery of Marfan's syndrome and related conditions of the aortic root (annulo-aortic ectasia)

The surgical treatment of 14 patients with annulo-aortic ectasia and aortic valve regurgitation secondary to cystic medial necrosis is presented. Resection of the aneurysm and replacement with a tubular graft, and aortic valve replacement with a rigid prosthesis, are advocated for definitive treatment. Eighty-six per cent of the patients survive and are doing well six months to four and a half years after surgery.

Reemplazamiento valvular aórtico con autoinjerto pulmonar ( operación de Ross) , en pacientes adultos y pediátricos. Estudio preliminar

Introduccion y objetivos. El reemplazamiento valvular aortico con autoinjerto pulmonar (opera-cion de Ross) se ha llegado a establecer como uno de los mejores metodos quirurgicos para el reemplazamiento de la valvula aortica en determinados grupos de pacientes. Aunque fue descrita por Ross en 1967, han tenido que pasar muchos anos para que, a la vista de la experiencia acumulada, las indicaciones se hayan extendido, incluso, a pacientes recien nacidos y pediatricos con formas complejas del tracto de salida de ventriculo izquierdo. El objetivo de nuestro trabajo es aportar la experiencia y resultados preliminares en un grupo de quince pacientes (adultos y pediatricos), intervenidos con esa tecnica. Material y metodos. En 6 pacientes la etiologia fue congenita y en 9 adquirida. Dos de ellos inter-venidos previamente con circulacion extracorporea, por obstruccion severa del tracto de salida de ventriculo izquierdo. Resultados. En todos ellos, se realizo procedimiento de Ross con insercion del autoinjerto pulmonar en forma de raiz total en posicion aortica, con reimplantacion de coronaria. La media de dia-metro de los homoinjertos pulmonares criopreservados fue de 26,1 ± 4 mm (19-35). En todos los casos se hizo estudio ecocardiografico transesofagico intraoperatorio y postoperatorio (1-2 meses). Solo un caso presento insuficiencia leve del autoinjerto pulmonar y ningun caso tuvo gradiente transaortico o transpulmonar postoperatorio. Un paciente fue reintervenido por hemorragia precozmente, ningun paciente presento complicaciones significativas y no hubo ningun caso de mortalidad hospitalaria, ni en el seguimiento a corto plazo (41-155 dias). Todos los pacientes estan libres de tratamiento anticoagulante en grado funcional I de la New York Heart Association. Conclusiones. En los resultados ecocardiograficos preliminares a corto plazo de nuestra serie, que incluye pacientes adultos y pediatricos, se observa un excelente comportamiento hemodinamico del autoinjerto pulmonar.

Homograft valve preparation and predicting viability at implantation.

An experimental study was performed using C14 proline uptake in order to: (1) assess the effects of current sterilization and storage methods on fibroblast viability, and (2) establish a control tissue that could be used to determine viability of each homograft valve at the time of impiantation in the clinical setting. The results were expressed as disintegrations per minute per milligram of tissue (DPM/mg). Swine aortic (AV), pulmonary (PV), and tricuspid leaflets (TV), and adjacent AV and PV arterial wall were procured sterile and subjected to routine sterilization and storage. Thirty samples of AV were analyzed for incorporation of labeled proline at procurement (208 ± 7 DPM/mg), following 48‐hour antibiotic exposure (87 ± 6 DPM/mg, P < .0001), and following controlled rate cryopreservation and storage for 12 days at •80°C (78 ± 8 DPM/mg, P = .42). Proline uptake of the other tissues at the same intervais disclosed that only the TV resulted in the same degree of viability at implantation (AV 78 ± 8, PV 68 ± 3, TV 75 ± 2, P = NS). The homograft valves were obtained under sterile conditions from brain dead, multi‐organ donors (homovital). It has been postulated that these valves are sterile and ready for implantation. Of 17 homovital valves cultured at procurement, 9 had positive cultures within 48 hours (53%). We conclude that: (1) the TV can be processed as a control tissue with each homograft and then utilized to predict viability at the time of implantation in the clinical setting; (2) antibiotic exposure is an essential step in the preparation of all homografts, however, modification of the antibiotic solution is necessary.

Morbidity following the Ross operation.

Aortic valve replacement (AVR) with a pulmonary valve autograft (PVA) was first reported by Donald N. Ross in 1967. The expectation of this procedure was to avoid degenerative changes seen in other biological tissue valves such as calcification, attenuation, and rupture of the leaflets. Recent reports by the original investigators group have confirmed the lack of degenerative changes in PVA. To corroborate their conclusions, the fate of 12 patients undergoing AVR with PVA by Dr. Gonzalez‐Lavin has been ascertained.

Mitral valve replacement with viable aortic homograft valves.

Abstract Forty consecutive patients underwent mitral valve replacement with viable aortic valve homografts. Viability was assessed by autoradiography in a sample of the aortic wall of the graft at the time of insertion. Sixty to 75% of the fibroblasts were found to be metabolically active. All patients were in New York Heart Association Functional Class III or IV prior to operation. Pulmonary hypertension was present in 37. One patient died in the hospital, and 1 late death occurred 9 months postoperatively. Anticoagulants were discontinued 6 weeks after operation without thromboembolic complications. Thirty-six of the patients showed marked clinical improvement, and only 3 patients were found to have a mild degree of mitral regurgitation by angiography. This experience has encouraged us to continue with this method of mitral valve replacement.

Autologous fascia lata transplantation for heart valve replacement A two-year experience at the National Heart Hospital, London

Between April 1969 and December 1970, 201 patients underwent 262 valve replacements with frame-mounted autologous fascia lata valves in the aortic, mitral, and/or tricuspid positions at the National Heart Hospital. A single fascia lata valve was inserted in 146 patients and multi-valve replacement was performed in 55 instances. Hospital and late mortality are comparable with that following other procedures of heart valve replacement. One hundred and fifty-four patients with 193 fascia lata valves were available for follow-up. A retrospective analysis of this method of valve replacement has been undertaken to assess the suitability of fascia lata as a heart valve substitute as well as the clinical results achieved by this method of valve replacement.