Faculty Bibliography

Percutaneous total cardiopulmonary bypass offers the advantage of rapid, simple implementation without the need for thoracic incision and provides the ability to support both left and right ventricular failure as well as pulmonary insufficiency. Previous studies using roller pump percutaneous bypass were only partially successful because of the inability to effectively unload the left ventricle. In the present experiment we attempted to determine in a normal canine model whether use of synchronous pulsatile pumping for percutaneous bypass could overcome this problem. Fourteen dogs were placed on percutaneous bypass for 1 hour. A roller pump was used in seven and a synchronous pulsatile pump with an electrocardiogram triggering mechanism in the other seven. All animals were maintained on percutaneous bypass for 1 hour. In the pulsatile pump group there was a significantly greater percent decrease from baseline in tension-time index (-56.3% versus -19.1%, p less than 0.01) and in myocardial oxygen consumption (-45.8% versus +2.1%, p less than 0.05) and a significantly greater percent increase in the endocardial/epicardial blood flow ratio (27.6% versus -6.5%, p less than 0.01) than in the roller pump group. These results show that superior unloading can be achieved by percutaneous pulsatile bypass compared with percutaneous roller pump bypass. The findings suggest that percutaneous total cardiopulmonary bypass with a synchronous pulsatile pump offers a relatively simple but effective method for providing appropriate patients with temporary hemodynamic stability before cardiac catheterization or medical or surgical revascularization

Sixteen hundred and forty-three porcine prosthetic values (1102 Carpentier-Edwards, 541 Hancock) were implanted in 1492 patients at New York University Medical Center between January 1976 and June 1983. The aortic valve alone was replaced in 786 patients (53%), mitral valve alone in 556 (37%), and multiple valves in 143 patients (9.6%). Concomitant coronary artery bypass was performed in 326 patients (22%). There were 116 deaths within 30 days of operation (7.8%). Follow-up (mean: 42 months) was completed in 94% of survivors and revealed that late survival from cardiac-related death was 87% at 5 years and 81% at 7 years, with no significant difference between the Carpentier-Edwards and Hancock patients. Late thromboembolic complications, however, were significantly more frequent in Hancock patients at all intervals from 1-7 years (p less than 0.05), whether in the aortic or mitral position. Patients with coronary artery disease who had concomitant coronary bypass showed a survival from late cardiac death that did not differ significantly from that of patients undergoing valve replacement alone. Before operation, 87% of patients were in New York Heart Association Class III or IV, but after operation 80% were in Class I or II. Late anticoagulant complications, endocarditis, and valve dysfunction were relatively rare. These results from a series of such size, duration, and representative numbers of two types of porcine bioprosthesis confirm excellent results with porcine prostheses in the first 4-5 years following operation

Experiences with 14 patients undergoing rupture of the left ventricle following mitral valve replacement over a period of 9 years have been described. Three different types have been recognized. Before 1978, most injuries occurred in the atrioventricular groove, apparently resulting from traction that insidiously avulsed the mitral annulus from the underlying left ventricular muscle. Several changes in operative technique, described in the text, were made to prevent this traction avulsion. Following the adoption of these principles, rupture in the atrioventricular groove virtually disappeared. A second type of injury, strut perforation, has been recognized in only one patient, a small 81-year-old female in whom the prosthesis inserted was too large for the ventricular cavity. Translucent obturators were subsequently developed not only to size the left ventricle but also to note the location of the post of the porcine prosthesis before insertion. Further problems of this type have not been seen. The most puzzling, and currently the most significant, problem is a third type of rupture, the mid-ventricular rupture, suggested as Type III by Miller in 1978 and described in detail by Cobbs in 1977 and 1980. The phenomenon seems to be a true spontaneous rupture of a thin left ventricle, usually occurring in small elderly women with mitral valve disease. If the friability of the left ventricle is transiently increased with potassium cardioplegia, such ventricles may spontaneously rupture following division of the chordae to the annulus of the mural leaflet. If this concept is correct, a rupture in some patients can best be prevented by preserving these chordae. It is well realized, of course, that a fortunate narrative experience of 3 1/2 years does not have any statistical value concerning a complication that occurs in 1 to 2% of operations. The experiences are reported, however, because to our knowledge, the untethered loop hypothesis has not been previously evaluated in a large number of consecutive patients operated on. Future comparison of experiences reported by others should make it possible to determine whether or not this concept is correct

A total of 20 children with total anomalous pulmonary venous drainage (TAPVD) underwent complete repair within the past six years. The drainage was supracardiac in 11, infracardiac in seven, and into the coronary sinus in two. At repair mean age was nine weeks, and weight was 3.7 km. Operative technique in extracardiac types included complete mobilization of the common vein with division of anomalous channel when possible. The incision in the confluent vein was extended into the lobar veins when necessary to permit extensive incorporation of this structure into the posterior wall of the left atrium and resulted in a nonobstructing stellate-type anastomosis. Operative mortality was 10% (2 of 20). Deaths occurred only in the group of infants in whom severe obstruction to pulmonary venous return required emergency operation, and one of these patients has persistent neurologic deficit. Late cardiac catheterization has been performed in 11 of 18 survivors. Nine had no or only minor abnormalities and two required reoperation. There have been no late deaths with follow-up of 2-8 years (mean = 4 years). Currently, all of the survivors are without cardiac symptoms and only one requires cardiac medication. Our experience identifies pulmonary venous obstruction with critical symptoms as the major operative risk factor in patients with TAPVD. With early operation prior to onset of critical symptoms, mortality is low and functional results are excellent

The development of myocardial ischemia is known to elicit the formation and enlargement of collateral vessels. The stimulus for these events is unknown. We have investigated the possibility that cardiac tissue releases a factor that can stimulate endothelial cell proliferation. Hearts from New Zealand rabbits were made progressively ischemic by differential hypothermia. Extracts from these hearts were tested for their growth-stimulating ability and were found to increase the proliferation of fetal bovine aortic endothelial cells as well as DNA synthesis by 3T3 cells. The level of activity in the extracts appears to be related to the degree of ischemia as measured by creatine phosphokinase levels. The liberation of an endothelial cell growth factor by ischemic cardiac tissue may function in the initiation and/or potentiation of coronary collateral formation

The results of the selective management of 300 abdominal stab wound victims have been reviewed for a 5-year period. Initially the need for laparotomy was evaluated by sinography, later physical examination, and most recently by local wound exploration combined with peritoneal lavage. The use of sinography resulted in an unnecessary laparotomy rate of 38%. Exploration based upon physical findings eventuated in 36% unnecessary laparotomies, of which 79% were negative, 17% morbidity, and no mortality. Local wound exploration followed by peritoneal lavage when peritoneal violation was suspected resulted in 8% unnecessary laparotomies of which half were negative, 9% morbidity, and no mortality. Based on this experience we have adopted the following approach to abdominal stab wounds. Patients with unexplained blood loss or overt signs of visceral injury undergo prompt exploration. In all other cass with intact peritoneum are discharged from the Emergency Department. If peritoneal violation is evident peri toneal lavage is performed. If the lavage is positive laparotomy is undertaken, and if negative the patient is hospitalized for an additional 24 hours of observation