Biomedical subjects

E A Lefrak

Publications and source records attributed to E A Lefrak.

13 recordsLinked to original sources

PubMed1992

Surgical complications in bridging to transplantation: the Thermo Cardiosystems LVAD.

Left ventricular assistance with a number of different devices has been used to successfully bridge patients to cardiac transplantation. Surgical complications or complications related to the device itself, however, may preclude transplantation or lead to death. We report our recent experience with the Thermo Cardiosystems model 14 "HeartMate" left ventricular assist device in 3 patients. The device was implanted for 15 to 95 days. Complications included mediastinitis and peritonitis associated with the device in place before transplantation, and colonic perforation, and a late diaphragmatic hernia after transplantation. Despite these and other minor complications, all 3 patients underwent successful cardiac transplantation. Mechanical support for the right ventricle was not necessary. The Thermo Cardiosystems left ventricular assist device provided excellent support in a range of physiological conditions with no mechanical malfunction despite the surgical complications.

Adult↗

PubMed1992

Multicenter clinical evaluation of the HeartMate 1000 IP left ventricular assist device.

The Thermo Cardiosystems Inc (Woburn, MA) HeartMate 1000 IP left ventricular assist device (LVAD) has been evaluated as a bridge to transplantation in 34 patients for up to 324 days at seven clinical centers in the United States. Sixty-five percent of the patients underwent transplantation, 80% of whom were discharged from the hospital. Six additional control patients, transplant candidates who met the entrance criteria but who did not receive the device, were also included in the study. Although 3 (50%) of the control patients received transplants, all 6 died within 77 days of having met the LVAD inclusion criteria (100% mortality). Complications resulting from use of the device were comparable with those previously reported for all ventricular assist devices, except for thromboembolic events: bleeding, 39%; infection, 25%; and right heart failure, 21%. No device-related thromboembolic events occurred, although 1 patient experienced an event related to a mechanical aortic valve in the native heart. None of the complications had a significant negative association with outcome of the patient except for right heart failure. All survivors had a significant improvement in hepatic function before transplantation. Total bilirubin values were reduced by 60% during LVAD support. No significant differences were observed when total bilirubin values were compared at 30 and 60 days after LVAD support and at 30 and 60 days after transplantation in a cohort of 15 patients (p greater than 0.05). The improvement in renal function was less predictable than that of hepatic function. Creatinine values decreased significantly before transplantation; however, the values measured at 30 and 60 days after transplantation were higher than those measured at the same intervals after LVAD support had been initiated, and this increase is presumably related to the immunosuppressive drugs. In conclusion, the HeartMate 1000 IP LVAD has been shown to be effective in supporting end-stage cardiomyopathy patients to transplantation. Thromboembolism, previously regarded as a serious complication with such devices, has not been a problem with this device. Additional patients are being enrolled into the study to further document the safety and effectiveness of this technology.

Adolescent↗

PubMed1991

Traumatic rupture of the interventricular septum and tricuspid valve: case report.

Cardiac injury following blunt trauma is an important cause of morbidity and mortality and is often unsuspected. Isolated chamber rupture and valvular injury are infrequent but recognized consequences of nonpenetrating trauma. This report describes a patient who developed a perimembranous ventricular septal defect and disruption of the septal leaflet of the tricuspid valve as a consequence of blunt trauma. Diagnosis and management of traumatic ventricular septal rupture are discussed.

Accidents, Traffic↗

PubMed1991

Celiac artery aneurysms: case reports.

Two recent patients with celiac artery aneurysms focus attention on the relevant diagnosis and therapeutic alternatives that lead to a successful outcome in these patients. Awareness of the nonspecific symptoms associated with splanchnic arterial aneurysms combined with ultrasonography, computerized axial tomography, and arteriography lead to the appropriate diagnosis of a celiac artery aneurysm prior to rupture and exsanguinating hemorrhage. Aneurysm resection offers a definitive means of treatment. Selective use of revascularization techniques bolsters the surgical approach by preventing hepatic ischemia and serving as an additional source of visceral arterial blood flow. Our use of an autogenous or prosthetic graft from the intrarenal abdominal aorta proved to be a helpful adjunctive technique. Long-term vigilance is important because of the association of celiac artery aneurysms with other arterial occlusive and aneurysmal disease.

Adult↗

PubMed1990

Coronary artery bypass surgery: emerging trends in mortality.

In a consecutive series of 4,697 patients undergoing coronary artery bypass surgery, these risk factors were found to be significant for increased postoperative mortality: age greater than 70, female sex, unstable angina, prior myocardial infarction, hypertension, diabetes mellitus, and ejection fraction less than .40. A comparison by year (1980-1988) revealed a steadily increasing incidence of these risk factors. Future analysis of coronary artery bypass mortality should include risk-factor stratification.

Aged↗

PubMed1989

Cardiac transplantation: goals and two-year results.

Results of cardiac transplantation have improved steadily following the first successful operation in 1967. However, rejection, infection, hypertension, hypercholesterolemia and accelerated coronary artery disease remain important late problems after successful heart transplantation. Facilitated patient access to the transplant center based upon geographic proximity to the home, family, and primary care physicians leads to enhanced care by allowing the original transplant team to remain actively involved with ease in the long-term follow-up. With this goal in mind, a cardiac transplantation center was developed with emphasis on developing an organized approach to providing care for patients with refractory congestive heart failure in the Virginia, West Virginia, Washington, D.C., Maryland, and Delaware area. Twenty-one of the 22 patients (95.4 per cent) survived and resumed active lives one to 26 months following heart transplantation. Forty-four rejection episodes occurred and were treated successfully, primarily on an outpatient basis. Only six infections were serious enough to require readmission to Fairfax Hospital, but all responded completely to treatment. Cardiac transplantation at a center focusing on regional patient care is not only less costly and more comfortable for patients and their families, but the continuity of care and comprehensive management of late complications can lead to improved long-term survival rates.

Delaware↗

PubMed1989

Cardiac transplantation in a regional center: goals and results at two years.

Cardiac transplantation moved from the realm of an investigational procedure to a therapeutic modality in the early 1980s. While one-year survival of 80 percent or greater can be expected, close follow-up is required to monitor for rejection, infection, and other late complications. With the need for close surveillance, both short and long-term, improved patient access to the transplantation center based on geographic proximity allows enhanced care by the original transplant team.

Adolescent↗

PubMed1979

Current heart valve prostheses.

Current heart valve prostheses may be classified as either mechanical or tissue valves (bioprostheses). The principal advantage of mechanical devices is their established long-term durability; however, chronic anticoagulation is recommended to reduce the incidence of thromboembolic complications. Tissue valves are associated with a relatively low rate of thromboembolism but their durability level has not been determined. All contemporary prosthetic heart valves yield comparable survival rates.

Aortic Valve↗

PubMed1977

Aortic valve replacement: a ten-year follow-up of non-cloth-covered vs cloth-covered caged-ball prostheses.

From 1965 to 1976, 721 isolated aortic valve replacements were performed at the University of Oregon hospitals, utilizing Starr-Edwards caged-ball prostheses. Three models of aortic prostheses were introduced during this period: a non-cloth-covered model has been in continuous use since 1965; a cloth-covered model was begun in 1968 and has been supplanted by the modified composite-strut or "track" model since 1972. The 5-year actuarial survival rate for operative survivors is about 80% for both non-cloth-covered and cloth-covered valves, while the 10-year survival is 61%, based on the older model only. The actuarially-determined percentages of patients experiencing significant thromboembolic episodes (i.e., all except transient ischemic episodes) at 5 years are 7% for the cloth-covered and 9% for the non-cloth-covered model. If transient ischemic attacks are included, the cloth-covered model has only an 8% incidence at 5 years compared to a 22% incidence for the older model. However, the cloth-covered valves are subject to a higher risk of reoperation because of the possibility of cloth injury. The "track" valve, therefore, was designed with exposed metal on the inner surface of each strut to prevent ball-cloth contact. In 107 patients (mean follow-up period 1 year) receiving anticoagulation, this prosthesis has maintained the same low incidence of thromboembolism as the previous cloth-covered model, with no reoperations for valve failure.

Aortic Valve↗

PubMed1976

Knee dislocation. An illusive cause of critical arterial occlusion.

Popliteal artery injury is a hazardous and often subtle complication of traumatic knee dislocation. Review of the literature in which series of knee dislocations were reported has revealed a 28% incidence of thrombosis or rupture of this critical vessel. Fifty-seven percent of these patients required leg amputation. The most frequent cause of limb loss has been absence or delay of direct surgical repair of the associated popliteal artery injury. This report describes a management plan that is intended to minimize the likleihood of future disabling leg amputations following knee dislocation.

Abdominal Injuries↗

PubMed1975

In situ preservation of cadaver kidneys for transplantation: laboratory observations and clinical application.

Many kidneys obtained from cadaver donors undergoing sudden cardiac arrest cannot be transplanted due to the long periods of warm ischemia from the moment of arrest to nephrectomy. A double-ballon-triple-lumen catheter for the rapid in situ preservation of cadaver kidneys has been designed. Used in combination with equipment routinely found in any hospital, it can cool human kidneys in situ to 10-15 C and maintain this temperature until nephrectomy can be performed. Kidenys preserved with this catheter have functioned after transplantation into suitable recipients. This report describes the design and laboratory evaluation of this new device, its clinical effectiveness and technique of insertion.

Adolescent↗

PubMed1975

Surgical technique for creation of an arteriovenous fistula using a looped bovine graft.

We have used bovine grafts in a looped configuration in the forearn in 150 patients for chronic hemodialysis and have evolved a simple technique for their successful implantation. The critical technical points include: 1) use of large-diameter long grafts (7.0-8.0 mm diameter; 34-40 cm in length); maintenance of the heterograft in a distended and pulsating state throughout the procedure to prevent distortion and twisting; 3) creation of a wide smooth-looped tunnel with Bakes dilators; and 4) anastomosis to the largest avialable antecubital vein. Thirteen cases of late graft occlusion (3-36) months) have been found to be produced by a localized obstructive lesion just distal to the venous anastomosis. These grafts were easily restored to a functional status by thrombectomy and patch graft angioplasty of the stenotic segment. The looped graft technique is not applicable to all patients requiring hemodialysis but it is especially helpful when distal vessels have been obliterated by previous procedures or when home-dialysis is planned. This surgical technique should be among the alternatives considered by surgeons concerned with problems of vascular access in patients with chronic renal failure.

Animals↗

PubMedDate not supplied

Mediastinitis complicating successful mechanical bridge to heart transplantation.

A 22-year-old man with severe end-stage cardiomyopathy required placement of a left ventricular assist device. Purulent mediastinitis and peritonitis developed while the device was in place. The patient survived a prolonged course of treatment, with mediastinal and peritoneal irrigation and parenteral antibiotics, before undergoing a successful heart transplantation 12 weeks after placement of the left ventricular assist device.

Adult↗