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The authors report two cases of left ventricular aneurysm associated with post-infarction ventricular septal rupture. This rare association, usually aggravated by high mortality, received successful surgical treatment.

The case is presented of a patient with congenital tricuspid stenosis who was treated successfully by a palliative open operation. The preoperative diagnosis was tricuspid atresia. At operation, however, congenital tricuspid stenosis was detected and managed by commissurotomy.. The postoperative course was very good. Later, the associated ventricular septal defect (VSD), pulmonary annular stenosis, and probably the atrial septal defect (ASD) will be corrected. We emphasize the importance of diagnosing congenital tricuspid stenosis correctly, because of the possibility of operating upon the valve itself.

After surgical removal of a portion of the cardiac wall, homologous dura mater cardiac grafts were sutured to the margins of the incision in the sternocostal wall of the right ventricle of the canine heart and recovered after 1, 4, 6 and 8 weeks of implantation. Representative tissue specimens were processed for and studied by means of SEM and TEM. The primary objectives were to study morphological changes in the dura mater grafts used to repair the lesions or defects in the cardiac wall and to compare alterations in the periosteal and arachnoidal aspects of the dura mater grafts after being implanted for varying periods of time. After one week of implantation, an amorphous layer of fibrin was deposited on or near the luminal surface of the original dura mater grafts. At four weeks of grafts implantation, a 'remodeling' process was apparent below the luminal surface of the graft. Although a large accumulation of fibrin was still present at this time, there was also an increase in the number of cellular and fibrillar components within the implant. Large numbers of macrophages and active fibroblasts were visible at this time along with new collagen. At the sixth week of implantation, an abundance of active fibroblasts, the presence of normal collagen and a darkly staining material interpreted as recently synthesized connective tissue components, fibrin deposits and/or degenerating collagen were also observed. Phagocytosis of the remaining fibrin was noted during this period indicating a continuation of the remodeling process at the luminal surface. Finally, after eight weeks of implantation, it was revealed that the original densely woven and relatively acellular graft had become infiltrated with various blood cells and vascular channels.

Eighty out of eighty-six patients (93%) with mammary artery implants were followed postoperatively for an average of three and a half years. The immediate mortality rate was 7% (6 cases), and the late mortality was 6% (5 cases). All had angina preoperatively. Twenty-four had a history of myocardial infarction and thirty-one were on limited physical activity, because of the pain. After surgery, thirty-three (45%) became asymptomatic. The angina improved significantly in thirty-five (47%) and remained unchanged in six (8%). Improvement in ventricular repolarization on ECG was observed in 69% of the patients. Postoperative cineangiography was performed in twenty-three patients; thirteen with single and ten with double implants. Out of the total of thirty-three implants, four (12%) were obstructed and twenty-seven patent (82%); twenty were in two cases of double implant, only one implant could be satisfactorily studied effectively functioning (61%). No obstructions were seen in the single implants. Non functioning implants were found in five (38%) of the thirteen single implants and in two of the twenty double ones (10%). The highest incidence of obstruction or non-functioning implants occurred in the group that did not show improvement (43%). This rate fell to 40% in the group that had some improvement and to 29% in those that were completely asymptomatic. Twelve of the eighteen patent mammary implants (67%) on the anterior wall of the left ventricle and eight of nine (89%) on the lateroinferior wall, established collateral circulation to the coronaries. Indication for surgery was considered satisfactory for nineteen out of the twenty-three patients and poor in four. There were two cases of obstruction of the implant (7%) in the group where surgery was correctly indicated and three of the twenty-three (11%) patent implants were non-functioning. Clinical improvement of the angina occurred in 84% in the first group and 50% in the other. In conclusion, this technique of indirect revascularization of the myocardium is valid for patients with severe diffuse lesions of the coronaries with a collateral network and preserved myocardial contractility.

A group of 533 patients had cardiac valves replaced with homologous dura mater valves. The dura mater was preserved in a solution of 98 per cent glycerol and antibiotics for a period of 12 days before used. The leaflets were mounted in a stainless steel ring covered by Dacron velour. Two hundred forty-five patients had mitral valve replacement; 205 patients, aortic valve replacement; 17 patients, tricuspid valve replacement; and 2 patients, pulmonary valve replacement. Sixty-four patients were subjected to multivalvular replacements. The patients were followed for a period of 1 to 40 months after surgery with satisfactory clinical and hemodynamic results. Because 2 patients developed endocarditis produced by fungii, fungicidal drugs were added to the preservative solution. No bacterial endocarditis has been observed. No pressure gradient through the valve has been noted at rest. Anticoagulant drugs have not been used in the postoperative period.

The clinical use of homologous dura mater cardiac valves was begun in January 1971. Between January 1971 and May 1975, 751 patients received 849 dura mater valves: 428 mitral, 365 aortic, 52 tricuspid and 4 pulmonary. The hospital mortality observed in this series was 13.6% and late mortality was 2.5%. The main causes of death were low-output syndrome in the immediate post-operative period or cardiac failure in the late post-operative period, due to myocardial impairment. Paravalvular leaks and errors in the manufacture of the valve were the main causes of regurgitation both in the immediate and late post-operative period. The incidence of thromboembolism, bacterial and fungal endocarditis was: 0.79%, 0.39%, 0.53% respectively. The results obtained with dura mater valve in a period of four years are satisfactory from the clinical and hemodynamic points of view.

The problem of artificial pumping of the blood has been solved relatively recently with the development of apparently simple aids in the form of a propulsion pump proposed by De Bakey in 1934 and modified by Leonard and Ankeney in 1958 (1). This machine is composed of two or more wheels that compress the rubber tube one after another, thus moving the blood during rotation.

We have reported the successful use of homologous dura mater preserved in glycerin at room temperature to repair large defects of the thoracic wall or diaphragm in five patients. The surgical technic involved the use of autologous bone grafts in order to stabilize the thoracic cage in one case, but in the other four the dural blade was sufficient. The postoperative course was uneventful regarding the structure and function of the dural implant in each case.