285 Ann Thorac Cardiovasc Surg Vol. 10, No. 5 (2004) Original Article Introduction Rejection is one of the most important reasons for al- lograft dysfunction after cardiac transplantation. Several studies have suggested a role for humoral mechanisms in significant and often irreversible, heart transplant rejec- tion. 1,2) Hammond et al. 3) defined humoral rejection in endomyocardial biopsy specimens by demonstrating cap- illary deposition of immunoglobulin and complement by immunofluorescence and capillary endothelial cell swell- ing in hematoxylin-eosin-stained paraffin-embedded tis- sue. The clinical course is more aggressive and hemody- namic compromise more frequent. 2) Patients with humoral rejection face increased risks of fatal rejection and accel- erated transplant vasculopathy. 2) The original technique of standard orthotopic heart transplantation (SOHT technique), as described by Lower and Shumway, 4) anastomoses the donor’s atria to those of the recipient, leaving a large cuff of the recipient’s right and left atria. Another technique, termed “total orthotopic heart trans- plantation” (TOHT), employs separate anastomoses of the right and left pulmonary veins and of the superior and inferior venae cavae. 5) The potential advantage of this technique is better preservation of the anatomy and func- tion of the atria of the transplanted heart as demonstrated Hemodynamics during Humoral Rejection Events with Total Versus Standard Orthotopic Heart Transplantation Ivan Aleksic, MD, 1 Dov Freimark, MD, 2 Carlos Blanche, MD, 3 Lawrence SC Czer, MD, 3 and Alfredo Trento, MD 3 From 1 Department of Thoracic and Cardiovascular Surgery, Uni- versity Essen, Essen, Germany; Divisions of 2 Cardiology and 3 Cardiothoracic Surgery, Cedars-Sinai Medical Center, Los An- geles, CA, U.S.A. Received February 6, 2004; accepted for publication May 20, 2004. Address reprint requests to Ivan Aleksic, MD, PhD, FETCS: De- partment of Thoracic and Cardiovascular Surgery, Universitätsklinikum Essen, Hufelandstr. 55, 45122 Essen, Germany. Purpose: We hypothesized that total orthotopic heart transplantation (TOHT) improves hu- moral rejection hemodynamics compared with biatrial transplantation or standard orthotopic heart transplantation (SOHT). Methods: We reviewed 1942 biopsies from 134 patients (pts) and right heart catheterization data obtained at endomyocardial biopsy. Biopsies that displayed humoral rejection by histologi- cal findings and positive immunofluorescence for immunoglobulins and complement were ana- lyzed. Patients with pacemakers, atrial fibrillation or -blocker therapy at the time of biopsy were excluded. Thirty-two pts after TOHT and 22 after SOHT matching these criteria were identified. Results: Demographic data, underlying disease, pretransplant hemodynamics, and donor de- mographics were similar. Cardiac output and index were higher in the total orthotopic group (5.9±1.1 vs 5.1±1.4 L/min, p=0.027; 3.3±0.5 vs 2.8 ±0.6 L/min/m 2 , p=0.016). Right atrial and pulmonary capillary wedge pressure were lower after TOHT (7±3 vs 11 ±5 mmHg, p<0.001; 13 ±4 vs 16±5 mmHg, p=0.035). Pulmonary pressures, pulmonary vascular resistance and heart rate were similar. Conclusion: TOHT offers improved hemodynamics during humoral rejection as evidenced by higher cardiac output and index with lower right atrial and pulmonary capillary wedge pres- sures. Future studies must examine the potential benefits of TOHT during combined cellular and humoral rejection events. (Ann Thorac Cardiovasc Surg 2004; 10: 285–9) Key words: heart transplantation, rejection, hemodynamics