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F A Arabia

Publications and source records attributed to F A Arabia.

At least 19 recordsLinked to original sources
PubMed2001

Bridge to transplantation with a Thoratec left ventricular assist device in a 17-kg child.

A Thoratec left ventricular assist device (LVAD) was used to support a 7-year-old 17-kg boy with viral cardiomyopathy for 23 days before heart transplantation. The boy is still living more than 1 year posttransplant, and functional except for some spastic paresis of the left hand, a residual from a stroke during device support. He is the smallest person to be supported with this device. We discuss techniques for using the Thoratec in children.

Body Weight↗
PubMed2001

Comparison of the CardioWest total artificial heart, the novacor left ventricular assist system and the thoratec ventricular assist system in bridge to transplantation.

BACKGROUND: Device selection has historically been supported by minimal comparative data. Since 1994, we have implanted 43 patients with the CardioWest Total Artificial Heart (CW), 23 with the Novacor Left Ventricular Assist System (N), and 26 with the Thoratec Ventricular Assist System (T). This experience provides a basis for our device selection criteria. METHODS: We reviewed retrospectively the results for survival, stroke, and infection in the CW, N, and T groups. Statistical methods included the Student's t-test, chi2 analysis, and Kaplan-Meier actuarial survival curves. RESULTS: The T group patients were younger and smaller sized than the CW or N group. The CW group had the highest mean central venous pressure (CVP) and lowest mean cardiac index. Survival to transplantation was 75% for CW, 57% for N, and 38% for T. Multiple organ failure postimplant caused most deaths in the CW and T groups. Right heart failure and stroke caused most N deaths. Linearized stroke rates (event/patient-month) were 0.03 for CW, 0.28 for N, and 0.08 for T. Serious infections were found in 20% of CW, 30% of N, and 8% of T patients, but linearized rates showed little difference and death from infection was rare. CONCLUSIONS: The N device should be used in "stable" patients with body surface area (BSA) greater than 1.7 m2 and with minimal right heart failure. Unstable patients with biventricular failure should receive a CW if the BSA is greater than 1.7 m2 or a T if they are smaller.

Adolescent↗
PubMed2001

Synthetic membrane neo-pericardium facilitates total artificial heart explantation.

BACKGROUND: In the past, explantation of the Cardio West total artificial heart (TAH) has been technically challenging because of the presence of dense adhesions and extremely thickened pericardium. To prevent this, we constructed a synthetic neo-pericardium in 14 patients. METHODS: Using expanded polytetrafluoroethylene (e-PTFE) membrane, we constructed a pericardium within the pericardium, or "neo-pericardium," completely covering the Cardio West TAH separating the native atria from the native pericardium, and wrapping the ascending aorta from the outflow conduit distally for about 5 to 7 cm. RESULTS: Of the 14 patients, 9 were transplanted and could be evaluated, 3 died on device support, and 2 are currently on device support. In each case, we attained faster (by 25 minutes) and easier reentry through the sternum. Surgical planes around the aorta, over the right and left atria, and throughout the pericardial space became apparent immediately after e-PTFE membrane removal. The pericardium and related tissues although slightly thickened (<2 mm) were pliable compared with our previous 36 patients, with very thick adherent pericardium over the device and native atria. CONCLUSIONS: The plastic materials forming the ventricular housing and drivelines of the Cardio West TAH and the Dacron outflow conduits have in the past caused profound local inflammatory reactions, resulting in extremely dense adhesions and thickened adherent pericardium. Using e-PTFE membrane to fashion a complete neo-pericardium and to wrap the ascending aorta at the time of Cardio West implantation dramatically reduces adhesions and pericardial thickening and facilitates explantation.

Adult↗
PubMed2000

Blood loss and transfusion requirements in patients implanted with a mechanical circulatory support device undergoing cardiac transplantation.

Patients implanted with mechanical circulatory support devices (MCSD's) are at high risk for post-operative bleeding at cardiac transplantation. However, the magnitude of the risk and transfusion requirements for MCSD patients at the time of transplantation have not been previously reported. The purpose of this study was to characterize and compare the bleeding characteristics and transfusion requirements of 3 sub-groups of cardiac transplant patients: primary (n = 45), redo (n = 26), and MCSD (n = 23) patients.

Blood Component Transfusion↗
PubMed2000

The CardioWest total artificial heart as a bridge to transplantation.

The CardioWest total artificial heart (TAH), formerly known as the Jarvik-7 and then the Symbion heart, is the only TAH in current clinical use. A new study, approved by the Food and Drug Administration (FDA), was initiated in 1993 with the goal of approving this pump for commercial release. Since then, 145 CardioWest TAHs have been implanted, including 37 pumps in 36 patients at our center. Our 36 patients were studied prospectively according to the investigational device exemption protocol approved by the FDA. Clinical and hemodynamic data obtained upon patients' entry into the study identified this group as mortally ill. After receiving a CardioWest TAH, 29 of the 36 patients (81%) survived to heart transplantation, and 26 (72% of the total group and 90% of the transplant recipients) have survived for up to 7 years (average, 24 months). Multicomponent anticoagulation, based on readily available tests, and the intrinsic properties of the TAH have resulted in a low linearized stroke rate of 0.48 event per patient-year. There have been no device-related mediastinal infections. In dying patients with nonexistent or severely compromised biventricular function, the CardioWest TAH has proved safe and effective, allowing a 72% survival rate for an average of 24 months.

Adult↗
PubMed1999

Arizona experience with CardioWest Total Artificial Heart bridge to transplantation.

BACKGROUND: We hypothesized that bridge to transplantation with the CardioWest Total Artificial Heart would succeed in a large percentage of patients. Further, we hypothesized that this success rate would not be significantly decreased by infection or thromboembolism. METHODS: From 1993 to March 1999, 24 patients received implants with the intention of bridge to transplantation. Data were collected prospectively. Heparin, coumadin, aspirin, ticlopidine, dipyridamole, and pentoxifylline were used for anticoagulation. RESULTS: Four patients died while on device support. Nineteen of 23 patients (83%) were transplanted. All 19 survived long term. One patient remains on CardioWest Total Artificial Heart support 6 weeks after implant. There was one stroke on the day of transplantation. There was a second stroke on the day of implantation. Neither stroke caused significant residual deficits. Both were in close relationship to an operative procedure. There were no serious device-related infections. CONCLUSIONS: The CardioWest Total Artificial Heart salvaged 20 of 24 critically ill patients. Neither infections nor neurologic problems were significant. We believe it is the device of choice for decompensating patients with biventricular failure who have adequate body and heart size.

Adult↗
PubMed1999

Implantation technique for the CardioWest total artificial heart.

The CardioWest total artificial heart is a pneumatically driven device that totally replaces the failing ventricles. It is currently undergoing clinical investigation as a bridge to heart transplantation in several centers throughout the world. A bilateral ventriculectomy is performed and the device is implanted. Blood flows are usually maintained at 6-8 L/min. Approximately 130 patients have undergone bridge to transplant with this device. Patient selection and excellent surgical technique are required for a successful outcome. A detailed description of the implantation technique is presented to facilitate the use of this technology.

Anastomosis, Surgical↗
PubMed1999

CardioWest total artificial heart: a retrospective controlled study.

The CardioWest total artificial heart (TAH) is a pneumatic device that is used as a bridge to heart transplantation and the only TAH available that totally replaces the failing ventricles. It has been utilized in selected centers in the U.S.A. with approval from the Food and Drug Administration. Strict criteria have been developed to select candidates to be bridged with the TAH. The patient must be a heart transplant candidate of age >18 and <59 years with a body surface area (BSA) > or = 1.7 m2, cardiac index (CI) <2.0 L/min/m2, and 2 inotropic agents or 1 plus an intraaortic balloon pump (IABP). A total of 24 heat transplant candidates (Group A) met the entry criteria and underwent placement of the TAH between January 1993 and July 1996. Group A consisted of 23 males; 16 patients had an IABP. The control group (Group B) consisted of 18 heart transplant candidates who met the TAH entry criteria but never received a TAH. Group B consisted of 15 males; 14 patients had an IABP. Preimplantation pulmonary vascular resistance (PVR) (Wood units), serum creatinine (mg/dl), and total bilirubin (mg/dl) were determined in both groups. The mean values for Groups A and B were, respectively, age: 47 and 47 years, BSA: 2.01 and 1.93 m2, CI: 1.5 and 1.8 L/min/m2, PVR: 2.88 and 2.47 Wood units, creatinine: 1.5 and 1.6 mg/dl, and bilirubin: 1.8 and 1.4 mg/dl. In Group A, 1 patient died on the TAH, 1 patient died after transplant, and 22 patients reached transplant and were discharged home for a survival rate of 91.7%. In Group B, 10 patients died while waiting for a heart transplant. Of the 8 patients transplanted, 7 survived and were discharged home for a survival rate of 38.9% (p = 0.0003). In summary the CardioWest TAH provided an excellent and successful method of bridging patients to heart transplantation with a reasonable risk.

Female↗
PubMed1998

Endomyocardial biopsy in the heterotopic heart transplant patient.

We present a technique for rapid and easy endomyocardial biopsy of the heterotopic transplanted heart. With a recent resurgence in heterotopic heart transplantation, we believe that ours is a sound technique in obtaining both routine surveillance biopsies as well as evaluating "right-sided pressures" in the "piggy-back" heart.

Biopsy↗
PubMed1997

International experience with the CardioWest total artificial heart as a bridge to heart transplantation.

As the number of potential heart donors remains constant and the number of potential recipients continuous to increase, the need for circulatory devices to bridge patients becomes more important. The CardioWest total artificial heart (TAH) is a pneumatic, implantable system that totally replaces the failing ventricles. It has been utilized worldwide as a bridge to heart transplantation in 79 patients. There were 73 males and six females who received the TAH. Currently three patients remain on the device waiting for transplantation. A total of 55 patients (70%) were transplanted of which 50 survived (91% of patients transplanted) and were discharged home. Idiopathic/dilated cardiomyopathy was the most common etiology followed by ischemic cardiomyopathy. The mean duration of implant was 34 days (range 0-186 days) and the mean age of the group was 45 years (range 16-62 years). Twenty-one patients died while on the device. Multiple organ failure was the major cause of death. There were a total of 255 complications in this group that included reoperation, bleeding, hepatic failure, renal failure, respiratory failure, neurologic events, thromboembolic events, infections, device malfunction, and fit complications. This represented a mean complication rate of three events per patient. The survival rate for the CardioWest TAH of 91% of the patients who reached transplantation is an improvement over that of the Symbion registry (55% of those transplanted) probably as a result of a better patient selection and better control of the coagulation system. These results are also comparable to those survival results obtained with other biventricular and left ventricular assist devices currently available.

Adolescent↗
PubMed1996

Heart-lung transplantation in situs inversus.

Reconstruction was accomplished in a 2 heart-lung recipients with situs inversus resulting in a left-sided systemic venous atrium. We created a large common atrium that was closed on the left side, leaving an atrial cuff on the inferior right quadrant. To this we anastomosed the donor right atrium, which had been opened laterally between the cavae. This resulted in some clockwise rotation of the ventricles and anterior positioning of the apex. The right pulmonary veins passed superior to the atrial anastomosis and posterior to the donor right atrium. Cardiopulmonary function was excellent in both cases.

Adolescent↗
PubMed1996

Bridge to transplantation with the CardioWest total artificial heart: the international experience 1993 to 1995.

BACKGROUND: After reapproval by the Food and Drug Administration of the CardioWest total artificial heart for clinical investigation, an international study was started in January 1993 to ascertain the safety and efficacy of this device for bridging to heart transplantation. To date, 40 devices have been implanted in five centers. METHODS: Retrospective data collection from participating centers provided enough material for analysis of patient selection, patient survival, adverse events, and comparison with contemporary devices used for bridge to transplantation. RESULTS AND CONCLUSIONS: Twelve patients (30%) died after implantation and before transplantation after an average of 10.6 +/- 10 days of support. The major cause of death in this group was multiorgan failure. Twenty-eight patients (70%) were supported 36 +/- 36 days before transplantation. There were two deaths after transplantation (1 rejection, 1 multiorgan failure) leaving 26 patients (65% of the total patients and 93% of those who were transplanted) who survived to discharge from the hospital. There was one late death from rejection at one month post discharge. The mean survival time of the 25 surviving patients is 12 months. These results compare favorably with those of other contemporary devices used for bridge to transplantation.

Adult↗
PubMed1995

Simplified technique of heart-lung transplantation.

Well-known complications of heart-lung transplantation include mediastinal bleeding and phrenic nerve injury. Conventional technique places the hila behind the phrenic nerves. We have placed the hila in front of the phrenic nerve in our last 10 patients, using direct caval anastomoses when feasible. This minimizes traction on and dissection around the phrenic nerves, and allows anterior rotation of the heart-lung block for easier hemostasis of the posterior mediastinum after implantation.

Dissection↗
PubMed1993

Incidence and recurrence of gastrointestinal cytomegalovirus infection in heart transplantation.

Cytomegalovirus (CMV) infection of the upper gastrointestinal tract is a major cause of morbidity in heart transplant recipients. Since April 1985, 201 patients underwent heart transplantation at our institution. Immunosuppressive therapy was with a triple drug regimen of cyclosporin A, prednisone, and azathioprine. Fifty-three of these patients had upper gastrointestinal symptoms, which primarily consisted of abdominal pain or nausea and vomiting despite prophylactic treatment with antacids, H2 blockers, or both. A total of 79 esophagogastroduodenoscopies were performed in this group; 15 patients required more than one esophagogastroduodenoscopy for recurrent symptoms. Of these 53 patients with persistent gastrointestinal symptoms, 16 (30.2%) had diffuse erythema or ulceration of the gastric mucosa (14), esophagus (1), and duodenum (1) with biopsy results that were positive for CMV on viral cultures (incidence, 8%). All patients with positive biopsy results were treated with intravenous ganciclovir at a dose of 10 mg.kg-1.day-1 in two divided doses for a period of 2 weeks. Recurrence developed in 6 patients (37.5%) and necessitated repeated therapy with ganciclovir. None of the 16 patients died as a result of gastrointestinal CMV infection. Patients who were seronegative for CMV and received a seropositive heart experienced earlier clinical manifestation of CMV infection. Infection of the upper gastrointestinal tract with CMV is a major cause of morbidity in cardiac transplant patients that may progress to a life-threatening complication if left untreated. Early diagnosis with esophagogastroduodenoscopy and biopsy for viral cultures is essential for documentation and proper management.

Adult↗
PubMed1993

Management of complications of Sideris transcatheter devices for atrial septal defect closure.

Various devices that can be inserted transvenously to close an ostium secundum atrial septal defect are undergoing clinical trials. Although these are safe and effective in most instances, they may occasionally dislodge or fail to "button" properly, causing migration and embolization. We report two cases in which the occluder and counteroccluder of the Sideris device for transvenous atrial septal defect occlusion (Custom Medical Devices, Amarillo, Tex.) failed to "button" appropriately, migrating in the right atrium in one patient and embolizing to the pulmonary artery in the second patient. An emergency operation was required to retrieve the device and repair the atrial septal defect.

Cardiac Catheterization↗
PubMed1991

Errors in pressure gradient measurement by continuous wave Doppler ultrasound: type, size and age effects in bioprosthetic aortic valves.

The accuracy of continuous wave Doppler ultrasound in deriving pressure gradients across bioprosthetic heart valves was evaluated in an in vitro pulse duplicator. Simultaneous pressure transducer and Doppler measurements were made in new and explanted aortic bioprosthetic valves of several sizes and four types: Carpentier-Edwards, Ionescu-Shiley, Hancock standard and Hancock modified. The mean and peak gradients calculated by the modified Bernoulli equation from Doppler velocity measurements were always greater than those measured manometrically, despite corrections for location dependence of the manometric gradient (or pressure recovery). The relation between manometric and ultrasonically determined gradient was found to be statistically dependent on the valve type (mean gradient p less than 0.0001; peak gradient p = 0.0003) and size (mean gradient p = 0.0089; peak gradient p = 0.0107). Effects of implantation were observed, but were not shown to be significant. It is concluded that the continuous wave Doppler velocity data overestimated prosthetic valve pressure gradient in all cases, even when pressure recovery was taken into account. Clinicians should be wary of Doppler data when making major diagnostic or therapeutic decisions.

Aortic Valve↗
PubMedDate not supplied

Success rates of long-term circulatory assist devices used currently for bridge to heart transplantation.

Circulatory assist devices as bridge to heart transplantation have become more important as the number of possible recipients has increased and the number of donors remains stable. The number of patients successfully bridged and discharged home after transplantation was determined for the Novacor Left Ventricular Assist System (Baxter Healthcare Corp., Oakland, CA) (LVAS), console and wearable; the TCI Left Ventricular Assist Device (Thermo Cardio Systems Inc., Woburn, MA) (LVAD), pneumatic and electric; the Thoratec LVAD and Biventricular Assist Device (Thoratec Lab Co., Berkeley, CA) (BIVAD); and the CardioWest total artificial heart (CardioWest Tech. Inc., Tuscon, AZ) (TAH). A total of 1,286 devices (14% Novacor console, 14% Novacor wearable, 35% TCI pneumatic, 4% TCI electric, 10% thoratec LVAD, 19% Thoratec BIVAD, and 4% CardioWest TAH) were implanted worldwide since 1984. A total of 776 (60%) patients reached heart transplantation and 687 patients (88.5% of those transplanted) were discharged home. The individual success rate for each device to bridge a patient to heart transplantation and be discharged home is as follows: Novacor LVAS console, 90%; Novacor LVAS wearable, 92%; TCI LVAD pneumatic, 89%; TCI LVAD electric, 89%; Thoratec LVAD, 93%; Thoratec BIVAD, 81%; and CardioWest TAH, 92%. The success rate with all the available systems to bridge a patient to heart transplantation and be discharged home is similar for all devices. The criteria used to determine which system to be used should be individualized for each patient. Some of the factors that should be considered in making a decision on which device to use should include anticoagulation, univentricular vs biventricular failure, mobility, protocol to discharge home, and size of the patient.

Adult↗