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Biomedical subjects

O H Frazier

Publications and source records attributed to O H Frazier.

At least 253 records · Page 14Linked to original sources
PubMed1991

Lipoprotein(a) and apolipoprotein changes after cardiac transplantation.

Although lipoprotein changes after cardiac transplantation have been documented, the effects of transplantation and subsequent immunosuppressive therapy (particularly the combination of prednisone, azathioprine and cyclosporine) on apolipoprotein levels and lipoprotein(a) have not been reported. Fasting cholesterol, triglycerides, high density lipoprotein (HDL) cholesterol, low density lipoprotein (LDL) cholesterol, apolipoprotein A-1 and B-100 and lipoprotein(a) were evaluated in 69 consecutive patients during the waiting period before cardiac transplantation. There were 28 deaths before donor organ identification and 41 patients received a cardiac allograft. The lipoprotein levels of transplant recipients were again assayed 3 months postoperatively. Mean (+/- SEM) values increased for total plasma cholesterol (from 180 +/- 8 to 228 +/- 8 mg/dl, p less than or equal to 0.001), triglycerides (from 126 +/- 11 to 207 +/- 14 mg/dl; p less than or equal to 0.001), HDL cholesterol (from 39 +/- 2 to 49 +/- 3 mg/dl; p less than or equal to 0.002) and LDL cholesterol (from 119 +/- 7 to 138 +/- 7 mg/dl; p less than 0.02). Apolipoprotein A-1 and B-100 also increased, but lipoprotein(a) decreased from 11.7 +/- 1.7 to 6.8 +/- 1.1 mg/dl; p less than or equal to 0.0001) after transplantation. Although total cholesterol, triglycerides, LDL cholesterol, apolipoprotein A-1 and B-100 increased dramatically after cardiac transplantation, so did HDL cholesterol, thereby keeping the LDL/HDL cholesterol ratio constant. The surprising decrease in lipoprotein(a) after cardiac transplantation suggests that metabolism of lipoprotein(a) is independent of LDL cholesterol and that immunosuppressive drugs either decrease the synthesis or increase catabolism of lipoprotein(a).

Apolipoproteins↗
PubMed1991

Cardiac transplantation in Puerto Rican patients at the Texas Heart Institute.

Cardiac transplantation is the treatment of choice for patients suffering from end-stage cardiac disease unamenable to conventional medical or surgical treatment. More than 390 patients have undergone heart transplantation at the Texas Heart Institute in Houston, and nine were Puerto Rican. Overall survival of these patients is 88%. Our experience with patients from Puerto Rico is described.

Age Factors↗
PubMed1991

Vascular trauma as a result of therapeutic procedures for the treatment of malignancy.

Twenty-two iatrogenic vascular injuries caused by resection of tumors with local recurrences or adjuvant chemotherapy were treated over a 42-month period in 11 female and 8 male patients with cancer (58% had documented metastases). Sixteen of 22 vascular injuries were caused by intraarterial administration of chemotherapy (8 emboli; 8 direct catheter trauma), and six were caused by resection of tumors with local invasion. The injuries were extremity ischemia (15 extremities in 13 patients), pseudoaneurysm (4), expanding hematoma (3 injuries in 2 patients). Twenty-two surgical repairs included bypass of severely damaged arteries in five, embolectomy in five, interposition grafts in three, pseudoaneurysm resection and primary repair in three, primary repair of three vascular injuries, and one patch angioplasty. Leg amputation was required in two patients. Seventeen of 19 patients had successful vascular repairs with resolution of preoperative indications for vascular repair without intraoperative or postoperative deaths. Long term follow-up (mean, 17 months) showed no recurrence of vascular problems; however, two patients died of metastatic cancer at 6 and 24 weeks after vascular repair. This study supports an aggressive approach to the management of vascular injuries caused by therapeutic interventions for malignancy despite the presence of metastatic disease.

Adolescent↗
PubMed1991

Progression of systemic disease and reduced long-term survival in patients with cardiac amyloidosis undergoing heart transplantation. Follow-up results of a multicenter survey.

Amyloid heart disease has been considered a contraindication for cardiac transplant based on the hypothesis that it is a systemic disease and that amyloid deposition would occur in the cardiac allograft. A survey was sent to all of the US centers and a limited number of Canadian and European centers listed with the International Registry. Twenty-four centers responded, and data were ultimately provided for a total of 10 patients (3 men, 7 women, mean age 48 years, range 30-60 years) who were transplanted for cardiac amyloid. The diagnosis of cardiac amyloidosis was made histologically on endomyocardial biopsy and/or examination of the explanted heart. Additional documented organ involvement included liver (two of 10), rectal (three of 10), renal (two of 10), gingiva (two of 10), and tongue (one of 10), although invasive biopsies were not performed in a majority of patients. A specific amyloid protein was identified in eight patients (seven lambda, one kappa immunoglobulin light chain). Although four of the surviving nine patients (one perioperative death) developed recurrent amyloid deposition in the allograft, it was detected solely by electron microscopy in two of these and had no clinical significance. There was, however, a progressive risk of major organ involvement with organ function impairment in this group (22% at 12 months, 50% at 24 months, 66% at 48 months). Although the immediate and early postoperative outcomes were not dissimilar between this group and patients undergoing transplantation for other cardiac diseases, late survival was reduced (39% at 48 months) compared with the larger population, but differences were not statistically significant due to the small amyloid sample size (p = 0.16).(ABSTRACT TRUNCATED AT 250 WORDS)

Amyloidosis↗
PubMed1990

Heart transplantation in Jehovah's Witnesses. An initial experience and follow-up.

More than 25 years of experience performing heart surgery on Jehovah's Witnesses has culminated in successful cardiac transplantation without administering blood products in five patients (mean age, 44.4 +/- 8.3 years) of this faith. The use of blood-conserving methods, iron supplementation, bone marrow-sparing maintenance immunotherapy, and brisk postoperative diuresis has added to the efficacy of cardiac transplantation in these patients. No perioperative deaths occurred, and early follow-up studies have shown that these patients have not been more susceptible to higher graft rejection rates due to the lack of pretransplant blood transfusions. As more Jehovah's Witnesses undergo heart transplantation in the future, comparison with other recipients who allow pretransplant blood transfusions may lead to a better understanding of rejection immunobiology. We conclude that cardiac transplants may be safely offered to Jehovah's Witnesses without fear of a uniformly poor outcome.

Adult↗
PubMed1990

Extension of donor criteria in cardiac transplantation: surgical risk versus supply-side economics.

To combat the continuing shortage of ideal donor hearts, we have used cardiac allografts from high-risk donors for critically ill recipients. We defined high-risk donor variables as age greater than 40 years, systemic (noncardiac) infection, cardiopulmonary resuscitation greater than 3 minutes, ischemic time longer than 5 hours, weight more than 20% less than that of the recipient, and requirements for high doses of inotropes. Of the 305 donors we have used, 73 (23.9%) have been high-risk, with 59/73 (80.8%) exhibiting one variable, 12/73 (16.4%) exhibiting two variables, and 2/73 (2.7%) exhibiting three variables. No correlation was found between the number of donor variables and a poor postoperative result. No infectious complications occurred in 17 patients receiving hearts from potentially infected donors. Hospital mortality rates (30 day) for recipients of high-risk donor versus non-high-risk donor hearts were 8.2% and 6.9%, respectively (not significant). The 1-, 6-, and 12-month actuarial survival rates were 91.7%, 81.2%, and 75.9% for the high-risk donor group and 93.5%, 80.3%, and 77.8% for the non-high-risk donor group (not significant). Among survivors with high-risk donor hearts, mean left ventricular ejection fractions were 0.54 +/- 0.08 at 3 months, 0.55 +/- 0.08 at 1 year, and 0.54 +/- 0.09 at 2 years after transplantation. These results suggest that accepting less than ideal donor hearts can be safe and might be considered when better options are not available.

Adult↗
PubMed1990

First human use of the Hemopump, a catheter-mounted ventricular assist device.

The Hemopump, a catheter-mounted, temporary ventricular assist device, consists of an external electromechanical drive console and a disposable, intraarterial axial-flow pump (21F). Power is transmitted percutaneously to the pump by a flexible drive shaft within the catheter. The device is positioned in the left ventricle by way of the femoral artery approach or through the ascending aorta. Blood is drawn from the left ventricle through the transvalvular inlet cannula and pumped into the aorta. As of December 1988, the Hemopump had successfully supported the circulation of 7 patients (5 men, 2 women) ranging in age from 44 to 72 years (mean age, 59 years) and suffering from cardiogenic shock (cardiac index less than 2.0 L/min/m2). Indications for use included failure to be weaned from cardiopulmonary bypass in 4 patients, acute myocardial infarction in 1, severe cardiac allograft rejection in 1, and donor heart failure in 1. Duration of support ranged from 26 to 113 hours (mean, 66 hours). Although 5 patients demonstrated transient hemolysis, none experienced infection, thrombosis, or vascular injury. Hemodynamic variables improved in all patients during support by the device. As of December 1988, 5 of the 7 patients were alive more than 30 days after support had been discontinued, and 3 of these patients were discharged from the hospital. On the basis of our initial clinical results, the Hemopump, which does not require a major surgical procedure for insertion, provides effective, temporary circulatory support in patients with potentially reversible cardiac failure.

Adult↗
PubMed1990

Rapid placement of the Hemopump and hemofiltration cannula.

Hypervolemia, a potential complication in patients on ventricular assist device support, can be managed by use of continuous arteriovenous hemofiltration. The Hemopump, a new catheter-mounted, transaortic axial-flow ventricular assist device, and the vascular access catheter for the Diafilter-30 Hemofilter system, used in continuous arteriovenous hemofiltration, are both usually inserted by way of the femoral artery. Because placing two large catheters in the femoral artery of a patient with peripheral vascular disease can compromise circulation, a technique for placing them in the abdominal aorta was developed. Two patients have undergone combined Hemopump and hemofiltration treatment, and neither experienced complications. Such techniques may benefit more patients in the future, as the usefulness of the Hemopump is proved.

Aorta, Abdominal↗
PubMed1990

Surgical treatment of cardiac tumors: a 25-year experience.

From 1964 to 1989, we performed operations on 133 patients with cardiac tumors. There were 58 male and 75 female patients ranging in age from three days to 81 years; 101 were adults, and 32 were children (less than 12 years of age). Primary tumors (102 benign and 12 malignant) were found in 114 patients and metastatic tumors in 19. Symptoms included congestive heart failure, arrhythmias, emboli, and chest pain. Diagnosis was accomplished through angiography, echocardiography, computed tomography, and magnetic resonance imaging. Operative treatment encompassed techniques ranging from biopsy to complete excision (including hypothermic circulatory arrest and cardiac autotransplantation) depending on the site of disease and the extent of involvement. Overall operative survival was 91%. Twelve patients died early (within 30 days of operation), and follow-up was obtained for 110 (90.9%) of the remaining 121 survivors (total patient-years of follow-up, 572.8; mean follow-up, 5.2 years). Of the 20 patients who died late, 15 had malignant disease. Operative survival for patients with primary cardiac malignancies and for those with metastatic disease was 83% and 68.4%, respectively, with 3 and 5 patients, respectively, still living. We advocate an aggressive surgical approach, especially in patients with benign tumors, who can expect an excellent outcome. For patients with malignant or metastatic disease, palliation and cure are also possible if aggressive surgical actions are taken.

Adenocarcinoma↗
PubMed1990

Use of potentially infected donor hearts for cardiac transplantation.

Despite the nationwide shortage of heart donors, more patients, some of whom are critically ill, are being accepted as candidates for transplantation. Thus, on occasion, we have liberalized our donor criteria to meet the demand. We have recently transplanted 16 potentially infected donor hearts into critically ill recipients. Of these 16 donors, 7 had multiple positive blood cultures as follows: Streptococcus pneumoniae (3), Staphylococcus aureus (2), Klebsiella pneumoniae (1), and Enterobacter sp (1). Seven other donors were accepted despite high fevers (rectal temperature greater than 38.9 degrees C), leukocytosis (greater than 18 x 10(9)/L [greater than 18,000 cells/microL]), and pulmonary infiltrates with positive sputa (Enterobacter [3], Klebsiella pneumoniae [2], and Staphylococcus [2]). Two other donors with hepatitis B surface antigen positivity were deemed at high risk but were used because the recipients were in immediate need. Early mortality (less than or equal to 30 days) among the recipients was 3/16 (18.7%) with 1 patient dying of uncontrolled allograft rejection, 1 of hepatic failure, and 1 of Pseudomonas septicemia. Late mortality (greater than 30 days after operation) occurred in 6 patients: 2 patients died of hepatic failure, 3 died of graft atherosclerosis, and 1 died of iatrogenic hemorrhage after a liver biopsy. Only 1 patient died of infection unrelated to that of the donor, and the other patients had no infectious complications resulting from the organisms identified in their respective donors. Use of potentially infected donor hearts resulted in surprisingly few infectious complications in this group of recipients. This practice can be safe and should be considered when other options are unavailable.

Adult↗
PubMed1990

Neo-intimal development on textured biomaterial surfaces during clinical use of an implantable left ventricular assist device.

Implantable left ventricular assist systems are being developed for long term clinical use. Prototype devices are currently used as extended mechanical bridges to cardiac transplantation. The Thermo Cardiosystems Inc. (TCI) pneumatic pusher plate left ventricular assist device (LVAD) features textured blood contacting surfaces to encourage the formation of an adherent fibrin-cellular coagulum. This serves as the foundation for the development of a neo-intimal lining. The TCI LVAD was implanted in 6 male patients (age range 22-53 years) between 1986 and 1988. The duration of implantation ranged from 1-41 days. No clinical thromboembolic events or pump-related thromboembolism occurred and none was evident at necropsy. The six device linings have been fully evaluated. Explanted devices were free of thrombus and calcification. Lining samples for light and electron microscopy were collected from areas of the diaphragm identical for flex and blood shear conditions and from high and low shear areas on the static housing. Islands of collagenous tissue were deposited on the static housing amongst compact fibrin. By day 13, cells populated the surface of the developing neo-intima overlying the diaphragm. By 41 days, the surface cell density increased and the cells became spindle shaped and relatively orientated in the high shear/flex area. Immunohistochemical techniques suggest that these cells are of mesenchymal origin. Textured blood contacting surfaces appear satisfactory in the preliminary clinical use of this device.

Adult↗
PubMed1990

Risk factors for development of accelerated coronary artery disease in cardiac transplant recipients.

Allograft coronary artery disease (CAD) is the major determinant of long-term survival following heart transplantation (HTx). In a group of 210 heart transplant recipients, we diagnosed CAD in 54 (27.1%) by coronary angiography, postmortem examination or examination of the transplanted heart at the time of retransplantation. Retrospective analysis of potential risk factors for the development of CAD was performed for both immunological (rejection pattern, immunosuppressive therapy, cytomegalovirus [CMV] infection), and nonimmunological (hyperlipidemia, smoking, hypertension, diabetes mellitus, obesity) risk factors. The total number of rejection episodes correlated significantly with the occurrence of CAD (P less than 0.05), showing that patients who experienced two or more rejection episodes had an incidence of CAD of 40%, as opposed to a 23% incidence in patients who experienced no rejection. A composite rejection score derived from multivariate regression analysis of the severity, frequency, and timing of acute cardiac rejection episodes was found to correlate with the development of CAD (P less than 0.05). Postoperative arterial hypertension also correlated significantly with the onset of CAD (P less than 0.01), with a 92.6% incidence of hypertension in the group with CAD versus 76.3% in the group without CAD. Smoking after transplantation correlated significantly with the occurrence of CAD (P less than 0.05). There was no significant correlation with other analyzed factors in this group of patients. In this review, the development of CAD after heart transplantation correlated with treated allograft rejection. Aggressive treatment of hypertension and cessation of smoking may contribute to alleviation of this serious complication.

Coronary Disease↗
PubMed1990

An experimental technique for heart-lung transplantation in subprimate models.

The success of heart-lung transplant experiments in subprimate models has been limited because most techniques include total pulmonary denervation, which causes respiratory problems, blood loss, and subsequent death. Using 20 subprimates (12 domestic swine and 8 mongrel dogs), we tested a heterotopic heart-single lung transplant method intended to preserve unilateral pulmonary innervation and to reduce blood loss. After native right pneumonectomy, the donor heart and right lung were transplanted en bloc. Anastomotic sites included the right primary bronchus, the superior vena cava, and the aorta. Selective left bronchial intubation and partial occlusion techniques eliminated the need for cardiopulmonary bypass and mediastinal dissection. All 10 recipient animals survived the operation, and the need for blood transfusions was minimal (1.1 +/- 0.7 [mean +/- SD] units/procedure). Donor and native lung function, assessed by selective left atrial blood gases, were similar: mean PO(2) was 229 +/- 31 mmHg and 180 +/- 25 mmHg, respectively; and mean PCO(2), 36 +/- 13 mmHg and 38+/-2 mmHg, respectively. Nine recipients were weaned from mechanical ventilation with a mean PCO(2) of 38+/-4 mmHg. Preserving unilateral pulmonary innervation allows normal respiration, and minimizing blood loss increases operative survival. Our method of heterotopic heart-single lung transplantation is reliable and could provide a functional heart-lung allograft for conducting future experimental studies of heart-lung transplantation.

Journal Article↗
PubMed1990

Concomitant donor heart coronary artery bypass grafting during orthotopic heart transplantation.

A 54-year-old diabetic woman with severe cardiomyopathy was placed on our heart transplant candidate list. The patient's condition rapidly worsened and a potential donor-a 45-year-old man whose blood was compatible with that of our patient-was located. Because of the donor's age, coronary arteriography was done, and stenosis in the midleft anterior descending coronary artery was identified. Since the patient's status was critical, the donor heart was accepted despite the presence of stenosis. We used the recipient's internal mammary artery to bypass the stenosis in the left anterior descending artery of the donor heart after performing a standard orthotopic heart transplant. The patient's postoperative course has been relatively free of complications, and the cardiac allograft has functioned well. The early results in this patient are comparable to those of our historical transplant control group. We suggest that the impact of donor organ shortages may be lessened by use of innovative procedures and extended donor selection criteria.

Journal Article↗
PubMed1989

Transmission of retroviruses by transfusion of screened blood in patients undergoing cardiac surgery.

We determined the rates of seroconversion to human immunodeficiency virus type 1 (HIV-1) and human T-cell leukemia virus Type I (HTLV-I) in a cohort of patients receiving transfusions of blood components screened for antibody to HIV-1. Preoperative and postoperative serum samples were collected from 4163 adults undergoing cardiac surgery who received 36,282 transfusions of blood components. The postoperative samples from all patients were tested for serologic evidence of HIV-1 infection, and those that were positive were compared with the corresponding preoperative samples. One case of HIV-1 transmission by transfusion of screened blood components was identified; two preexisting HIV-1 infections were found. Samples from 2749 patients were tested similarly for serologic evidence of HTLV-I infection; these patients received 20,963 units of blood components. Five new cases and two preexisting cases of HTLV-I infection were detected. The observed risk of HIV-1 transmission by transfusion was 0.003 percent per unit; the risk of HTLV-I transmission was 0.024 percent per unit. We conclude that there is a very small risk of HTLV-I infection from transfused blood products that have been screened for antibodies to HIV-1, but that it is nearly 10-fold higher than the risk of HIV-1 infection.

Acquired Immunodeficiency Syndrome↗
PubMed1989

Anastomosis of bypass grafts using a low-powered CO2 laser.

The purpose of this study was to evaluate the feasibility of using a low-powered CO2 laser to perform end-to-side anastomoses of bypass grafts. The internal jugular veins of 13 domestic swine were removed and used as grafts to bypass their ligated carotid arteries. Each end of the vein graft was apposed to the artery with four to six temporary stay sutures, and a waveguide delivery CO2 laser with a power density of 900 mW/mm2 was used to perform the anastomoses, after which the sutures were removed. The animals were sacrificed postoperatively at five time intervals: 2 to 4 hours, 5 days, 1 month, 3 months, and 5 months. Of the 10 anastomoses studied at 2 to 4 hours, 70% were fully patent, none thrombosed, and 30% disrupted. Of the 16 anastomoses studied between 5 days and 5 months postoperatively, 88% were patent, 12% thrombosed, and none disrupted. None of the animals developed aneurysms at any stage of this investigation. Histologic analysis of acute studies revealed thermal damage such as charring of tissue, unraveling of the collagen fibrils, and the formation of microvacuoles. Within 3 months, the anastomotic sites showed localized healing with intimal fibromuscular proliferation and dense fibrous tissue. Good apposition of tissue was found to be of great importance in achieving patency of vessels in this procedure.

Animals↗