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D W Benson

Publications and source records attributed to D W Benson.

167 records · Page 10Linked to original sources
PubMedDate not supplied

Pharmacologic reduction of pretransplantation pulmonary vascular resistance predicts outcome after pediatric heart transplantation.

Pulmonary hypertension leading to donor right ventricular dysfunction remains a major risk factor associated with poor outcome after heart transplantation. This study evaluated a pretransplantation protocol to assess pulmonary vascular resistance index and its response to pharmacologic modulation. Cardiac catheterization was performed in 25 patients (mean age, 8.6 years [range, 1 to 17 years]; mean weight, 27.3 kg [range, 8.1 to 54 kg]) with end-stage heart failure. Mean pulmonary artery and capillary wedge pressures and cardiac index were measured in the baseline state and during administration of 100% oxygen, dobutamine at 10 micrograms/kg/min, and nitroprusside at 1 to 4 micrograms/kg/min. Transpulmonary pressure gradient and pulmonary vascular resistance index were calculated. In 22 survivors, hemodynamics were reassessed 1 and 4 weeks after transplantation. The mean cardiac index significantly increased (2.2 to 3.2 L/min/m2); transpulmonary pressure gradient (12.7 to 9.6 mm Hg) and pulmonary vascular resistance index (6.2 to 3.0 units/m2) decreased during the drug study. In 12 patients with a baseline pulmonary vascular resistance index of more than 6 units/m2, 10 survived heart transplantation. This study shows that pharmacologic reduction of the pulmonary vascular resistance index in the pretransplantation protocol predicts reduced pulmonary vascular resistance index and a favorable outcome after heart transplantation.

Adolescent↗
PubMedDate not supplied

Spectrum of humoral rejection after pediatric heart transplantation.

The deposition of immunoglobulin and complement 3 in the coronary microvasculature (humoral rejection) has been associated with poor outcome after heart transplantation. The purpose of this study is to relate the incidence of immunoglobulin and complement 3 myocardial deposition to the clinical course of pediatric heart transplant patients. One hundred thirty-one biopsy specimens from 30 patients, whose mean age at transplantation was 4.9 years (range, 2 days to 17 years), were processed for light microscopy and immunofluorescence. The mean follow-up was 25 months (range, 6 to 63 months). All patients underwent annual selective coronary artery angiography. No cellular or humoral rejection was seen in 97 biopsy specimens. Humoral rejection without cellular infiltrate was found in eight biopsy specimens from four patients (13%). Of 19 grade 1A, B (mild) biopsy specimens, 17 showed only cellular rejection, and two showed a mixed pattern of cellular and humoral rejection. Of six grade 2,3 (moderate) biopsy specimens, four showed only cellular rejection, and two showed a mixed pattern. The only grade 4 (severe) biopsy specimen revealed a mixed pattern. Three patients have had persistent immunoglobulin M and complement 3 deposits. One of these had angiographic evidence of accelerated graft coronary artery disease 2 years after transplantation, which was later confirmed at autopsy. Coronary artery disease has not been detected by serial angiography at 1 year (28 patients), 2 years (18 patients), 3 years (15 patients), 4 years (five patients), and 5 years (one patient). Humorally mediated rejection occurs with and without cellular rejection after pediatric heart transplantation. Humoral rejection may persist after treatment and resolution of severe cellular rejection episodes.(ABSTRACT TRUNCATED AT 250 WORDS)

Biopsy↗