Operator-interactive method for simultaneous measurement of left and right ventricular volumes and ejection fraction by tomographic electrocardiography-gated blood pool radionuclide ventriculography.

Background: A method that uses single photon emission computed tomography (SPECT) equilibrium radionuclide angiocardiography (ERNA) to measure right ventricular (RV) and left ventricular (LV) volumes (in milliliters) and ejection fraction (EF) is described.

Methods And Results: We recorded 35 paired SPECT ERNA and electron beam computed tomography (EBCT) cardiac studies in 27 patients; for comparison with EBCT, a method for measurement of RV and LV volumes and EF with SPECT ERNA was developed in 18 paired studies and was validated and assessed for reproducibility in 17. Validation indicated that SPECT ERNA and EBCT were similar for measurement of RV volume (end-systolic and end-diastolic volumes in a combined analysis) and EF (180+/-74 mL vs 182+/-80 mL and 0.

An echocardiographic left ventricular wall area index for functional detection of myocardial injury in hemodynamically unloaded hearts.

Functional assessment of the left ventricle is affected by loading conditions. Detection of rejection-mediated myocardial injury in a heterotopic heart transplant model is a challenge for the echocardiographer because the heart is in an unloaded state. We examined the relationship of a novel left ventricular (LV) wall area index (LVWAI) and serum cardiac troponin T (cTnT) levels.

Prevalence, pathophysiology, and clinical significance of post-heart transplant atrial fibrillation and atrial flutter.

Background: Atrial rhythm disturbances, in particular atrial fibrillation (AF) and flutter (AFL), are common in the denervated transplanted heart. However, there is a relative paucity of data in the prevalence, mechanism of arrhythmia, and long-term significance.

Objectives: (1) Determine the prevalence of AF and AFL in heart transplant patients, (2) define the echo/Doppler features associated with arrhythmia, and (3) evaluate the impact of arrhythmia on long-term survival.

Sirolimus in cardiac transplantation: use as a primary immunosuppressant in calcineurin inhibitor-induced nephrotoxicity.

Background: Calcineurin inhibitor (CNI) immunosuppressants are a major cause of renal dysfunction in cardiac transplant recipients, leading to increased morbidity and mortality. The aim of this study was to evaluate the efficacy and safety of CNI withdrawal and substitution with sirolimus as the primary immunosuppressant, and assess the effect on renal function in cardiac transplant recipients with CNI-induced renal impairment.

Methods: Thirty-four stable cardiac transplant recipients (range 1 to 14 years post-transplant) with CNI-induced nephrotoxicity (iothalamate clearance 25 to 50 ml/min) or cardiac allograft vasculopathy (CAV) were enrolled.

Elevated donor troponin levels are associated with a lower frequency of allograft vasculopathy.

Background: Cardiac allograft vasculopathy (CAV) is considered a major cause of morbidity and mortality in transplant recipients and may reflect immune-mediated endothelial injury in response to the donor heart. Elevated troponin levels in the donor serum might provide a marker for this phenomenon; therefore, we evaluated the relationship of donor troponin levels to the development of CAV.

Methods: A retrospective analysis of troponin levels was undertaken from cardiac donor patients, and transplant recipients were monitored for the development of vasculopathy by angiography (N = 171).

Cyclosporine decreases vascular progenitor cell numbers after cardiac transplantation and attenuates progenitor cell growth in vitro.

Objective: Recent experimental evidence suggests that the neointimal proliferation seen in cardiac allograft vasculopathy may in part derive from recipient progenitor cells. The effect of cyclosporine on these circulating progenitors in the setting of cardiac transplantation is currently unknown.

Methods: Three surgical series were performed: sham operation alone, sham operation with immunosuppression, and heterotopic porcine cardiac transplantation with immunosuppression.

Successful use of Thoratec biventricular support in a small child awaiting cardiac transplantation.

The use of paracorporeal mechanical biventricular support devices either as a bridge to transplantation or while awaiting recovery of the failing heart has been well described in the literature. The majority of these reports detail conditions specific to the adult population. We describe use of the Thoratec ventricular assist device (Thoratec Corp, Pleasanton, CA) in the smallest known cardiomyopathy patient to date to be successfully supported with an emergent biventricular device before subsequent cardiac transplantation.

Surgical treatment of cardiac papillary fibroelastoma: a single center experience with eighty-eight patients.

Background: Cardiac papillary fibroelastoma is a rare benign tumor that can cause thromboembolism. We have found no large surgical series describing its treatment and outcome.

Methods: A retrospective review of all patients treated surgically for this tumor from 1985 to 2002.

Prognostic analysis for survival in adult solid organ transplant recipients with post-transplantation lymphoproliferative disorders.

Purpose: The objective of this study was to determine prognostic factors for overall survival in patients with post-transplantation lymphoproliferative disorders (PTLDs).

Patients And Methods: This study focused on the 107 adult solid organ transplantation patients who were diagnosed with PTLDs at Mayo Clinic (Rochester, MN) between December 1970 and May 2003.

Results: The median age at the time of diagnosis was 48 years (range, 15 to 75 years).

Cardiac xenotransplantation: recent preclinical progress with 3-month median survival.

Objectives: Transplantation is limited by a lack of human organ donors. Organs derived from animals, most likely the pig, represent a potential solution to this problem. For the heart, 90-day median graft survival of life-supporting pig hearts transplanted to nonhuman primates has been considered a reasonable standard for entry into the clinical arena.

The nature, time course and severity of methamphetamine withdrawal.

Aims: To characterize the natural history of methamphetamine withdrawal during the first 3 weeks of abstinence.

Design: Cross-sectional study with comparison group. Setting A substance use treatment facility in Chiang Mai Province, Thailand.

Rejection severity directly correlates with myocyte apoptosis in pig-to-baboon cardiac xenotransplantation.

Background: The process by which cardiac myocytes die during xenograft rejection is incompletely understood. The presence of cardiac myocyte apoptosis in discordant xenotransplant models has been noted, yet no investigators have examined whether a relationship between myocyte apoptosis and rejection severity exists. Thus, we chose to further investigate this observation.

Is early anticoagulation with warfarin necessary after bioprosthetic aortic valve replacement?

Objectives: Freedom from anticoagulation is the principal advantage of bioprosthesis; however, the American Heart Association/American College of Cardiology and the American College of Chest Physicians guidelines recommend early anticoagulation with heparin, followed by warfarin for 3 months after bioprosthetic aortic valve replacement. We examined neurologic events within 90 days of bioprosthetic aortic valve replacement at our institution.

Methods: Between 1993 and 2000, 1151 patients underwent bioprosthetic aortic valve replacement with (641) or without (510) associated coronary artery bypass.

Warfarin or low-molecular-weight heparin therapy does not prolong pig-to-primate cardiac xenograft function.

Microvascular thrombosis is a prominent feature in cardiac delayed xenograft rejection (DXR). We investigated the impact of warfarin or low-molecular-weight heparin (LMWH) anti-coagulation on xenograft function using a heterotopic pig-to-primate model. Donor hearts were from CD46 transgenic pigs and baboon immunosuppression included tacrolimus, sirolimus, anti-CD20 and TPC, an alpha-galactosyl-polyethylene glycol conjugate.

Sleep and breathing on the first night after adenotonsillectomy for obstructive sleep apnea.

Adenotonsillectomy (T&A) has established effectiveness for the treatment of obstructive sleep apnea (OSA). However, more than 20% of children with OSA have respiratory compromise requiring medical intervention in the postoperative period. The reasons for this complication are not well-defined.

Prevention, detection, and management of early bacterial and fungal infections in a preclinical cardiac xenotransplantation model that achieves prolonged survival.

Background: We analyzed bacterial and fungal infectious complications in a cohort of 16 consecutive experiments with the longest surviving cardiac xenografts to date.

Methods: Transgenic, porcine-to-baboon, heterotopic (abdomen) cardiac xenotransplantation was performed in 16 consecutive experiments, using rapamycin, tacrolimus, corticosteroids, anti-CD20 monoclonal antibody, and an alpha-Gal-PEG polymer, as immunosuppression. Prophylactic anti-microbials included i.

Differences between early and late posttransplant lymphoproliferative disorders in solid organ transplant patients: are they two different diseases?

Background: The objective of the authors' study was to characterize the clinical and pathologic differences between patients who develop posttransplant lymphoproliferative disorders (PTLD) early or late after transplantation and to assess the overall survival in these two groups.

Methods: One hundred seven adult solid organ transplant patients were identified at the Mayo Clinic between December 1970 and May 2003.

Results: Forty-nine patients developed PTLD within the first year (early PTLD, 1-11.

Operative risk of reoperative aortic valve replacement.

Objective: The contemporary risk of reoperative aortic valve replacement is ill-defined. We therefore compared the recent early results of reoperative and primary aortic valve replacement in our institution.

Methods: Between January 1993 and January 2001, a total of 162 patients underwent reoperative aortic valve replacement with or without coronary artery bypass grafting, and 2290 underwent primary aortic valve replacement with or without coronary artery bypass grafting.

Prognostic factors in patients with post-transplant lymphoproliferative disorders (PTLD) in the rituximab era.

To assess the effect of rituximab therapy and other prognostic factors on overall survival in patients with post-transplant lymphoproliferative disorders (PTLD) after solid organ transplantation, 30 consecutive patients diagnosed with PTLD between 1999 and 2002 were analyzed. Fifteen (50%) patients received rituximab (375 mg/m(2) once a week). Fifteen (50%) patients had other interventions including observation, immunosuppression reduction, surgery, chemotherapy, radiation or a combination of these.

Cardiac xenotransplantation: progress toward the clinic.

Background: Animal organs could satisfy the demand for solid organ transplants, which currently exceeds the limited human donor supply. Hyperacute rejection, the initial immune barrier to successful xenotransplantation, has been overcome with pig donors transgenic for human complement regulatory proteins. Delayed xenograft rejection, thought to be mediated by anti-pig antibodies predominantly to Gal antigens, is currently regarded as the major barrier to successful xenotransplantation.

Serum cardiac troponins and N-terminal pro-brain natriuretic peptide: a staging system for primary systemic amyloidosis.

Purpose: Primary systemic amyloidosis (AL) is a multisystemic disorder resulting from an underlying plasma cell dyscrasia. There is no formal staging system for AL, making comparisons between studies and treatment centers difficult. Our group previously identified elevated serum cardiac troponin T (cTnT) as the most powerful predictor of overall survival.

Mitral and tricuspid valve repair in patients with previous mediastinal radiation therapy.

Background: The purpose of this study was to evaluate outcomes of mitral and tricuspid valve repair after mediastinal radiation therapy.

Methods: From 1976 to 2001, 22 patients (mean age 61 +/- 14 years) underwent mitral (n = 14), tricuspid (n = 6), or both (n = 2) valve repairs 15 +/- 9 years after mediastinal radiation therapy. Concomitant procedures included coronary artery bypass graft, 11 patients; valve replacement, 6 patients (4 aortic, 3 mitral, 1 tricuspid, and 1 pulmonary); and pericardiectomy, 4 patients.