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H B Bittner

Publications and source records attributed to H B Bittner.

At least 19 recordsLinked to original sources
PubMed2007

Pharmacodynamics of T-cell function for monitoring immunosuppression.

OBJECTIVES: Recent studies show that measuring pharmacodynamic (PD) effects offers a unique possibility to predict immunosuppression. Thus, in this study we have monitored the PD properties of immunosuppressants on diverse T-cell functions in heart transplant (HTx) recipients. MATERIALS: PDs and blood concentrations (PK) of three different basis-immunosuppressive drugs were studied: cyclosporin A (CsA); tacrolimus (TRL) and sirolimus (SRL). T-cell function was analysed by expression of proliferating cell nuclear antigen (PCNA) labelling, expression of cytokines (IL-2, IFN-gamma) and surface antigen (for example, CD25) by FACS analysis. RESULTS: In group I, at time points C0 and C2, increased CsA-PK significantly inhibited expression of IL-2, IFN-gamma, PCNA and CD25 (P < 0.05). Correlations (r(2)) at C2 between inhibition of T-cell functions (PD) with PK and with drug doses were: CsA-PK: 0.71-0.91 and CsA-dose: 0.73-0.87. In group II, increased TRL-PK over time did not further inhibit expression of CD25, but inhibited PCNA expression more on day 3, and IL-2 and IFN-gamma expression was significantly higher on days 2 and 3 compared to PD effects of CsA (P < 0.05). Blood SRL concentrations in C0 group III, increased on day 1 and remained stable at days 3 and 4. Expression of PCNA was not altered in the SRL-PK category, whereas expression of CD25 was higher and expression of cytokines was lower than PD effects of CsA. CONCLUSIONS: Our results show that PD effects on T-cell function can be used to monitor immunosuppression bringing potential to increase the efficacy and safety of immunosuppressive therapy after HTx.

Aged↗
PubMed2005

C0h/C2h monitoring of the pharmacodynamics of cyclosporin plus mycophenolate mofetil in human heart transplant recipients.

UNLABELLED: Pharmacokinetic (PK) parameters like C2h have improved efficacy of immunosuppressive therapy. However, drug interactions, toxicities, and individual differences to drug effects still remain challenging. Therefore, this study was designed to assess pharmacodynamic (PD) effects of the combination cyclosporin (CsA) plus mycophenolate mofetil (MMF) on lymphocyte functions in peripheral blood of stable heart transplant recipients (HTx) using our established FACS assays. METHODS: Blood from 25 HTx patients was drawn before (C0h) and 2 hours after dosing (C2h). CsA and mycophenolic acid (MPA) concentrations were measured by EMIT. FACS assessed expression of cytokine production (IL-2, TNF-alpha), lymphocyte proliferation (PCNA), and T-cell activation (CD25, CD95). RESULTS: Evening doses of CsA (25/50/75 or 100 mg) and MMF (250/500 or 1000 mg) produced C0h levels as follows: CsA, 162 +/- 12 ng/mL; MPA, 1.7 +/- 0.2 mg/L. Morning doses of CsA (50/75 or 100 mg) and MMF (250/500/1000 or 1500 mg) produced C2h-levels as follows: CsA, 589 +/- 56 ng/mL and MPA, 7.4 +/- 1.3 mg/L. PD effects at C0h/C2h (% expression +/- SEM, all P < .05) were IL-2, 18 +/- 3/10 +/- 2; TNF-alpha, 12 +/- 2/7 +/- 1; PCNA, 8 +/- 1/5 +/- 1; CD25, 26 +/- 4/13 +/- 2; CD95, 23 +/- 4/11 +/- 2). Correlations (r2) at time point C2h between inhibition of lymphocyte functions (PD) with drug concentrations (PK) and with drug doses were CsA-PK, 0.71 to 0.91; MMF-PK, 0.55 to 0.76; CsA-dose, 0.73 to 0.87; MMF-dose, 0.61 to 0.80. CONCLUSION: For the first time, the immunosuppressive effects of the combination CsA plus MMF were quantified in whole blood of human HTx at different time points. PD assays may offer the opportunity to optimize clinical immunosuppressive drug therapy.

Antigens, CD↗
PubMed2005

Pharmacodynamic monitoring of the conversion of cyclosporine to tacrolimus in heart and lung transplant recipients.

OBJECTIVE: Conversion from cyclosporine (CsA) to tacrolimus (TRL) remains challenging in the daily routine due to individual variations in blood concentrations (pharmacokinetics, PK), pharmacodynamics (PD) and in interactions on plasma mycophenolic acid (MPA) concentrations. Therefore, we used our PD assays of lymphocyte function to monitor the conversion of CsA to TRL in heart (HTx) and lung (LTx) transplant recipients. METHODS: Patients (six HTx, two LTx) were converted from CsA to TRL because of gingival hyperplasia. All patients were treated with 6 mg BID TRL 24 hours after the last CsA dose and received mycophenolate mofetil BID cotherapy. PK measurements of CsA, TRL, and MPA were done by EMIT. Expression of cytokine production (IL-2, TNF-alpha), lymphocyte proliferation (PCNA), and activation (CD25) was assessed by FACS. RESULTS: TRL concentrations increased from day 1 to 3, but did not alter MPA concentrations, which were comparably high to MPA concentrations in combination with CsA (day 0). Compared to CsA therapy, increased TRL concentrations did not further inhibit PCNA expression, inhibited CD25 expression less on days 1 and 2 and equally high on day 3, but inhibited expression of IL-2 and TNF-alpha significantly higher on days 2 and 3 (P < .05). CONCLUSION: This study shows that monitoring PD of lymphocyte functions after conversion from CsA to TRL in HTx and LTx recipients revealed differences of inhibition of lymphocyte functions. Monitoring PD of lymphocyte function may provide insights in drug interactions of immunosuppressive combination therapy and may help to tailor immunosuppression to avoid toxicity and to enhance efficacy.

Cyclosporine↗
PubMed2003

Off-pump coronary artery bypass grafting in a patient with AIDS, acute myocardial infarction, and severe left main coronary artery disease.

A 48-year-old male patient with AIDS presented with postinfarct unstable angina, decreased left ventricular function (EF 35%), significant left main coronary artery disease, and total occlusion of the proximal left anterior descending and right coronary arteries. In order to avoid the potential immunosuppressive effect of cardiopulmonary bypass (CPB) in an already compromised host with an already low CD4+ helper/inducer T cell count (180/microL) and high retroviral load (165,000 copies/mL), the application of beating-heart technology and off-pump coronary bypass grafting was an ideal indication. The patient underwent successfully off-pump/CPB coronary revascularization. The triple drug combination of highly active antiretroviral therapy (HAART) was resumed postoperatively. The patient was discharged from the hospital on the 7(th) postoperative day. The CD4+ count was 142/microL and the viral load decreased to 450 copies/mL. Seven months post-operatively the patient was free of angina and without shortness of breath. The CD4+ count was 160/(m)L and the viral load undetectable. Improved survival of HIV positive patients has resulted in a shift from caring for terminally ill patients to caring for patients with chronic illness. While protease inhibitors have positively affected survival, they may also cause plasma lipid abnormalities, which can lead to severe premature coronary artery disease. Therefore, an increasing population of AIDS and HIV positive patients with coronary artery disease may require cardiac interventions in the near future. Coronary revascularization without CPB and its potential immunocompromising effect may play an important role in patients with severe coronary artery disease and AIDS.

Acquired Immunodeficiency Syndrome↗
PubMed2003

Off-pump coronary artery revascularization: ideal indication for patients with porcelain aorta and calcification of great vessels.

Patients with porcelain aorta and severe calcification of the great vessels are a challenging dilemma for the cardiovascular surgeon regarding bypass technique, choice of conduit, and selection of proximal anastomotic sites due to the high incidence of devastating thromboembolization and aortic injury. No currently proposed surgical approach avoids manipulation of the heavily calcified ascending aorta. Three patients presented with unstable angina and decreased ventricular function secondary to significant left main coronary artery stenosis and 3-vessel coronary artery disease. In addition to the coronary artery disease, severely calcified ascending aorta and great vessels were discovered. One patient presented with near total distal abdominal aortic occlusion, severe peripheral vascular disease, history of stroke, and carotid endarterectomy. Surgical coronary revascularization was indicated. Coronary artery bypass grafting using internal thoracic artery and greater saphenous vein composite arterial inflow grafts in combination with off-pump beating heart surgery was successfully used. Cardiopulmonary bypass and clamping of the aorta was avoided. No new neurologic deficit was observed. Coronary revascularization with internal thoracic artery composite grafts and avoiding cardiopulmonary bypass and clamping the calcified aorta is an effective method to prevent clamp injury and thromboembolization. Off-pump coronary artery bypass grafting seems to be an ideal indication in patients with porcelain aorta because the surgical techniques of "no-touch" and "no-cannulation" can be applied.

Aged↗
PubMed2001

Hyperacute rejection in single lung transplantation--case report of successful management by means of plasmapheresis and antithymocyte globulin treatment.

We describe the third case and first successful treatment of hyperacute rejection in a pulmonary allograft recipient and detail the immediate clinical findings. The patient underwent single right lung transplantation for severe emphysema and chronic obstructive pulmonary disease. Three hours after completion of the vascular anatomoses oxygen desaturation and increased airway pressure was noted in combination with graft edema, frothy, pink fluid draining from the bronchial orifice, hemodynamic instability, thrombocytopenia, and coagulopathy. The retrospective cross-match result was reported to be positive. The clinical diagnosis of hyperacute rejection was made. A donor-specific IgG HLA antibody to A2 was identified. The standard immune suppression regimen was immediately modified and a hyperacute rejection protocol applied including plasmapheresis and antithymocyte globulin treatment as well as cyclophosphamide to decrease antibody existence and production. A remarkable clinical recovery was observed after the fifth postoperative day and completion of plasmapheresis when a repeated retrospective cross-match showed significantly decreasing anti-donor reactivity.

Acute Disease↗
PubMed2001

Myocardial function in hearts with transgenic overexpression of the G protein-coupled receptor kinase 5.

BACKGROUND: Chronic heart failure is associated with impairment of the myocardial beta-adrenergic receptor (beta-AR) system. In this study, the effects of G protein-coupled receptor kinase 5 (GRK5) overexpression on myocardial performance were directly assessed in the hearts of transgenic mice using an isolated work-performing murine heart preparation and computerized analysis of functional data. METHODS: A controlled experimental study was performed to evaluate cardiac function in both transgenic mice with a 30-fold overexpression of GRK5 (n = 9, 23 to 29 g) and littermate controls (n = 10, 22 to 29 g). Preload-dependent cardiac output, contractility, stroke work, stroke volume, and heart rate were compared between the two groups. RESULTS: Significant decreases in preload-dependent cardiac output and contractility were observed in the mice with GRK5 overexpression when compared with control group mice and occurred in association with significant decreases in stroke work and stroke volume. There was no significant difference in the average heart rate between the two groups. CONCLUSIONS: These data suggest that GRK5 upregulation may be partially responsible for alterations in myocardial function in chronic heart failure.

Animals↗
PubMed2001

Management of porcelain aorta and calcified great vessels in coronary artery bypass grafting with off-pump and no-touch technology.

A 69-year-old woman presented with postinfarct unstable angina and decreased ventricular function secondary to significant left main coronary artery stenosis in combination with total right coronary artery occlusion. We did successful off-pump coronary revascularization in this patient with severely calcified ascending aorta and great vessels, subtotal aortobiiliac stenoses, a history of previous stroke, and right carotid endarterectomy.

Aged↗
PubMed2001

Off-pump coronary artery bypass grafting. Excellent results in a group of selected high-risk patients.

BACKGROUND: Off-pump coronary artery bypass grafting (OPCABG) has assumed an increasing role in many surgical practices. The ideal candidate has not been defined, but high-risk patients seem to benefit most when cardiopulmonary bypass (CPB), aortic cross clamping and cardioplegic arrest are avoided. METHODS: Fourteen high-risk patients (age 52 to 81 years, 1 female, EF 44%+/-8, Parsonnet score 23+/-4) were studied. They presented with acute coronary syndroms on platelet glycoprotein IIb/IIIa antagonists, acute myocardial infarction, worsening renal failure, decompensating ischemic cardiomyopathy, religious beliefs and denial of blood transfusion, and severe peripheral/cerebrovascular disease (total bilateral internal carotid artery occlusion and/or >90% stenosis). These patients underwent OPCABG via sternotomy with the intention of complete coronary revascularization. RESULTS: An average of 2.3 grafts/patient were performed and the posterior descending artery (PDA) and marginal branches of the circumflex artery (LCX) were grafted in 79% of the patients. There were 3 events of intraoperative cardiac arrest precipitated by occlusion of right coronary artery (RCA) or positioning a cardiomegaly heart leading to immediate intravascular shunting (2) and/or conversion to CPB (1). One patient was converted to CPB and graft revision (intraoperative ultrasound and probing). The mortality rate was 0% and one stroke was observed on post-operative day 1. Coronary angiography (n=6) showed no significant stenosis. CONCLUSIONS: OPCABG complete revascularization is feasible in high-risk patients with low morbidity and mortality and excellent early RESULTS: OPCABG may be indicated in patients on platelet receptor antagonists preventing bleeding complications. Cardiomegaly can cause difficult off-pump LCX and PDA exposure and stabilization. RCA grafting off-pump is less tolerated and PDA grafting is preferred. High-risk patients for CPB are the ones who may benefit the most from OPCABG.

Aged↗
PubMed2000

Surgical resection of an intracardiac rhabdomyoma.

There are only a few previous reports of intracardiac rhabdomyomas causing ventricular arrhythmias and near syncope. In this report we describe the successful surgical resection of an intracardiac rhabdomyoma using cardiopulmonary bypass, blood cardioplegia, and hypothermia. Preoperative evaluation consisting of echocardiography, computed tomography (CT), magnet resonance imaging (MRI), and positron emission tomography (PET) strongly suggested the presence of a symptomatic primary cardiac tumor projecting from the interventricular septum into the right ventricle.

Adult↗
PubMed1999

Molecular and functional mechanisms of right ventricular adaptation in chronic pulmonary hypertension.

BACKGROUND: Chronic pulmonary hypertension can lead to compensatory changes in the right ventricle. In this study, the adaptive mechanisms of the right ventricle in the setting of pulmonary hypertension were assessed at the molecular and functional level using a canine model of monocrotaline pyrrole-induced pulmonary hypertension. METHODS: Animals underwent pulmonary artery catheterization to measure pulmonary hemodynamics before and 8 weeks after an injection of monocrotaline pyrrole, 3 mg/kg (n = 8) or placebo (n = 8) (controls). Systolic function was assessed with load-insensitive means (preload-recruitable stroke work). Myocardial biopsy specimens were collected to analyze membrane alpha1- and beta-adrenergic receptor density and adenylate cyclase activity. RESULTS: Eight weeks after injection, significant increases in pulmonary hemodynamic indices were noted in monocrotaline-injected dogs. Significant increases in right ventricular preload-recruitable stroke work were also observed in these animals compared with controls and occurred in association with significant increases in right ventricular alpha1- and beta-adrenergic receptor density and isoproterenol hydrochloride-stimulated adenylate cyclase activity. No significant differences in basal adenylate cyclase activity in the right ventricle were noted between the two groups. CONCLUSIONS: These data suggest that alterations in right ventricular function in the setting of chronic pulmonary hypertension may partially be due to changes in myocardial adrenergic receptor signaling.

Adaptation, Physiological↗
PubMed1999

Right ventricular dysfunction after cardiac transplantation: primarily related to status of donor heart.

BACKGROUND: It is unclear whether right ventricular dysfunction after transplantation is due to donor brain death-related myocardial injury or recipient pulmonary hypertension. METHODS: A canine donor model of brain death and a monocrotaline pyrrole-induced chronic pulmonary hypertension recipient model were established, and used for 30 orthotopic bicaval cardiac transplantations divided into three groups: Controls (group A, normal donor/recipient), group B (brain-dead donors/normal recipient), and group C (normal donor/recipients with pulmonary hypertension). Right ventricular function was measured before transplant and brain death, 4 hours after brain death, and after transplant (1 hour off bypass) by load-independent means plotting stroke work versus end-diastolic volume during caval occlusion. Right ventricular total power and pulmonary vascular impedance were determined by Fourier analysis. RESULTS: In comparison to the control group right ventricular preload-recruitable stroke work and total power decreased significantly after brain death and transplant in group B (from 22.7 x 10(3) erg (+/-1.2) at baseline to 15.6 x 10(3) (+/-0.9) after brain death and to 11.3 x 10(3) (+/-0.9) after transplant). In group C there was a significant increase in pulmonary artery pressure, impedance, right ventricular preload-recruitable stroke work, total power after transplant. CONCLUSIONS: Normal donor hearts adapt acutely to the recipient's elevated pulmonary vascular resistance by increasing right ventricular power output and contractility. Brain death caused significant right ventricular dysfunction and power loss, which further deteriorated after graft preservation and transplantation. The effects of donor brain death on myocardial function contribute to right ventricular dysfunction after cardiac transplantation.

Animals↗
PubMed1998

Myocardial recovery after ischemia and reperfusion injury is significantly impaired in hearts with transgenic overexpression of beta-adrenergic receptor kinase.

BACKGROUND: beta-Adrenergic receptor kinase 1 (beta ARK1) mediates beta-adrenergic receptor signaling via receptor phosphorylation, which results in functional uncoupling. The physiological importance of beta ARK1 on cardiac performance in the setting of ischemia and reperfusion injury, however, has not been clearly established. In this study, the effects of beta ARK1 overexpression on myocardial recovery after ischemia and reperfusion injury were evaluated in transgenic mice with the use of an isolated work-performing murine heart preparation and computerized analysis of functional data. METHODS AND RESULTS: A controlled, experimental study was performed to compare cardiac function in the hearts of both transgenic mice with a 3-fold overexpression of beta ARK1 (n = 6; weight, 25 to 29 g) and littermate controls (n = 9; weight, 25 to 28 g). Preload-dependent cardiac output, contractility, heart rate, stroke work, and stroke volume were evaluated in the 2 groups before and after a 6-minute period of normothermic ischemia. Before ischemia, significant decreases were observed in all parameters of myocardial performance in beta ARK1 mice compared with control mice. After ischemia and reperfusion, significant decreases in cardiac function were observed in both experimental groups; however, significantly lower percentages of myocardial recovery occurred in beta ARK1 hearts compared with control hearts. CONCLUSIONS: After global normothermic ischemia, significant decreases in cardiac function were observed in both beta ARK1 and control mice; however, significantly lower percentages of myocardial recovery occurred in beta ARK1 mice. These data suggest that myocardial beta ARK1 overexpression significantly impairs cardiac function in the setting of ischemia and reperfusion injury.

Animals↗
PubMed1998

Pharmacological strategies for improving diastolic dysfunction in the setting of chronic pulmonary hypertension.

BACKGROUND: Right ventricular (RV) hypertrophy is an adaptive process that occurs in the setting of chronic pulmonary hypertension (CPH) and can lead to alterations in normal RV diastolic properties. This study was designed to investigate the effects of NO and milrinone on RV diastolic dysfunction in the setting of CPH and RV hypertrophy by use of a canine model of monocrotaline pyrrole (MCTP)-induced CPH. METHODS AND RESULTS: Sixteen mongrel dogs (22 to 24 kg) were used. Animals underwent percutaneous pulmonary artery (PA) catheterization to measure pulmonary hemodynamics before and 8 weeks after injection of 3 mg/kg MCTP (n=8) or placebo (control, n=8). Eight weeks after injection, all hearts were instrumented with a PA flow probe, sonomicrometric dimension transducers, and micromanometers. Data were collected at baseline and after both NO and milrinone administration. Diastolic properties were quantified by use of the end-diastolic pressure-volume relationship and the time constant of ventricular isovolumic relaxation. Eight weeks after injection, significant increases in the PA pressure and pulmonary vascular resistance were observed in MCTP dogs. Significant worsening of RV diastolic function occurred in association with significant increases in the ratio of RV dry weight to LV+septal dry weight. NO and milrinone administration both led to significant improvements in RV diastolic properties. CONCLUSIONS: In the setting of MCTP-induced CPH, significant worsening of RV diastolic function was observed in association with significant increases in the ratio of RV dry weight to LV+septal dry weight, suggesting that these changes are partially due to RV hypertrophy. The significant improvement in RV diastolic properties after both NO and milrinone administration suggests that these agents may be effective forms of pharmacological therapy for improving RV diastolic dysfunction in the setting of CPH.

Administration, Inhalation↗
PubMed1998

Physiologic effects of extracellular superoxide dismutase transgene overexpression on myocardial function after ischemia and reperfusion injury.

OBJECTIVE: Myocardial injury after ischemia and reperfusion may be mediated, in part, by oxygen-derived free radicals. In this study the protective effects of extracellular superoxide dismutase overexpression were directly assessed in the hearts of transgenic mice, after ischemia and reperfusion injury, using an isolated work-performing murine heart preparation and computerized analysis of functional data. METHODS: A blinded study was performed to compare cardiac function in the hearts of both transgenic mice with a 3.5-fold overexpression of myocardial extracellular superoxide dismutase (n = 6, 22 to 26 gm) and littermate controls (n = 8, 22 to 26 gm). Preload-dependent cardiac output, contractility, heart rate, stroke work, and stroke volume were evaluated in the two groups before and after a 6-minute period of normothermic ischemia. RESULTS: No differences were found between extracellular superoxide dismutase hearts and control hearts in any parameter of myocardial function before ischemia. After ischemia, decreases in cardiac output occurred in both groups; however, this decrease was larger in control mice compared with extracellular superoxide dismutase mice. A higher percentage of recovery was also observed in the contractility, heart rate, stroke work, and stroke volume of extracellular superoxide dismutase hearts compared with control hearts. CONCLUSION: After global normothermic ischemia and subsequent reperfusion, decreases in cardiac function occurred in both extracellular superoxide dismutase and control mice; however, a higher percentage of recovery was observed in the extracellular superoxide dismutase overexpressed hearts. These data suggest that extracellular superoxide dismutase transgene overexpression significantly improves preservation of myocardial function after ischemia and reperfusion injury.

Animals↗
PubMed1998

Hemodynamic and inotropic effects of milrinone after heart transplantation in the setting of recipient pulmonary hypertension.

BACKGROUND: Right ventricular failure remains an important cause of early morbidity and death after heart transplantation and is commonly related to preexistent recipient chronic pulmonary hypertension, which occurs as a result of long-standing congestive heart failure. In this study, the hemodynamic and inotropic effects of milrinone were assessed after bicaval heart transplantation in the setting of monocrotaline pyrrole-induced recipient chronic pulmonary hypertension. METHODS: Twenty dogs were used for 10 successfully completed transplantation experiments. Recipient animals underwent right atrial injection of 3 mg/kg monocrotaline pyrrole 4 months before transplantation. Hemodynamic and functional data were taken 1 hour after termination of cardiopulmonary bypass and after milrinone infusion. Myocardial function was assessed with load-insensitive means (preload-recruitable stroke work) and pulmonary vascular impedance was calculated with Fourier analysis. RESULTS: At the time of transplantation, before cardiopulmonary bypass, pulmonary hemodynamic indexes in recipient animals were significantly increased when compared with donors and were further significantly increased after cardiopulmonary bypass. Two animals died after transplantation as a result of acute right ventricular failure. In surviving animals milrinone infusion led to significant increases in right ventricular function, which occurred in association with significant improvements in pulmonary vascular impedance and transpulmonary efficiency. CONCLUSIONS: In the setting of monocrotaline pyrrole-induced recipient pulmonary hypertension, milrinone was associated with significant improvements in pulmonary vascular impedance, right ventricular function, and transpulmonary efficiency. These data suggest that milrinone is an effective means to improve right ventricular dysfunction and pulmonary vascular efficiency after bicaval heart transplantation in the setting of recipient chronic pulmonary hypertension.

Animals↗
PubMed1998

Right ventricular function in orthotopic total atrioventricular heart transplantation.

BACKGROUND: Total orthotopic heart transplantation was recently introduced into clinical practice as an alternative technique of orthotopic heart transplantation, adding bicaval and left and right pulmonary vein anastomoses to pulmonary artery and ascending aorta connection (total technique). The conventional technique (ventricular transplantation with atrioplasty) is compared with the total technique with particular emphasis on right ventricular performance. METHODS: Forty-eight mongrel dogs (23 to 31 kg) were used for 12 total and 12 standard orthotopic heart transplantations. Right ventricular (RV) function and atrial systole were analyzed with the use of micromanometry, sonomicrometry, and ultrasonic flow probes (preload-independent RV recruitable stroke work, RVPRSW). Fourier analysis was used to calculate RV power and pulmonary vascular impedance. RESULTS: There was no significant difference in cardiac ischemic and bypass times between the two groups. After transplantation, sinus rhythm was preserved after all total transplantations and after only one standard transplantation; no significant hemodynamic differences were observed. RVPRSW in the total group was conserved after transplantation; however, RVPRSW decreased by 39% (+/-8, p < .05) in the standard group. There was also a significant decrease in the rate of RV filling in the standard group after transplantation, suggesting decreased right atrial function. Pulmonary vascular impedance and RV power output were not significantly different after transplantation between the two groups. CONCLUSIONS: Total atrioventricular transplantation is a feasible alternative and conserves normal sinus rhythm. Ischemic and bypass times were not significantly different when the superior vena cava anastomosis is performed last after the release of the aortic cross-clamp. The insignificant decrease in the rate of RV filling with the use of the total technique suggests conserved RV diastolic function after transplantation with less decreased RV function in the total group.

Animals↗