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S A Hunt

Publications and source records attributed to S A Hunt.

At least 55 records · Page 3Linked to original sources
PubMed1992

Cardiac function after domino-donor heart transplantation.

A major limitation in cardiac transplantation is donor availability. A possible way to increase the supply of donor hearts is to use explanted hearts from patients undergoing heart-lung transplantation for primary lung disease. One potential advantage of this approach, termed domino-donor transplantation, is the existence of a donor right ventricle already adapted to pulmonary hypertension, which would therefore theoretically decrease the likelihood of acute donor right heart failure in recipients with preexisting elevation of pulmonary vascular resistance. Potential disadvantages include graft failure secondary to chronic effects of pulmonary hypertension on the right ventricle, arrhythmia and infections. Seven domino-donor transplants were performed at Stanford University Hospital; graft and patient survival to date are 100% at a mean follow-up of 20 months (range 1 to 26). Infection and rejection rates have been comparable to those of the current Stanford experience for conventional orthotopic transplantation. Right ventricular function and size have either improved or remained unchanged in all patients after transplantation. Transient early postoperative donor right ventricular dilation, a characteristic adaptive response seen in nondomino transplants, occurred in 4 patients with pulmonary hypertension before surgery. These data indicate that, with adequate assessment before surgery, domino-donor cardiac transplantation is an appropriate means of augmenting the donor pool.

Actuarial Analysis↗
PubMed1992

Emergency department presentation and care of heart and heart/lung transplant recipients.

STUDY OBJECTIVE: Heart and heart/lung transplants are accepted forms of therapy for patients with end-stage cardiac or pulmonary disease. These patients are likely to present postoperatively to the emergency department. To our knowledge, there have been no previous reports in the medical literature of the ED presentation of these patients. DESIGN: We conducted a retrospective review of the records of all patients who had received a heart or a heart/lung transplant at Stanford University Medical Center from 1988 through 1990 and who had at least one ED visit. MEASUREMENTS AND RESULTS: Between the time of operation and April 1, 1991, 131 ED visits were recorded. Fever was the single most common presenting complaint, for 48 (37%) of the visits. Difficulty in breathing (13%); gastrointestinal symptoms of nausea, vomiting, or diarrhea (10%); and chest pain (9%) were other common reasons for presentation. CONCLUSION: The transplant patient, by virtue of requiring chronic immunosuppression, is susceptible to infection with a spectrum of opportunistic organisms. When fever or other symptoms suggest infection, appropriate cultures and aggressive diagnostic procedures (eg, lumbar puncture, bronchoscopy) should be performed.

Adolescent↗
PubMed1991

Characteristics of serial electrocardiograms in heart transplant recipients.

To characterize "normal electrocardiogram patterns" after transplantation, serial surface 12-lead electrocardiograms (ECGs) taken 2 weeks, 1 month, and 1 year postoperatively in a group of 50 heart transplant recipients were analyzed and were correlated with clinical parameters. Some recipient atrial activity was evident in 40% of patients at 2 weeks, but in only 16% at 1 year; donor atrial activity was normal in 90% to 94% of patients at all times. ECG intervals generally were normal and did not change over time. The most prevalent abnormality was the presence of incomplete (IRBBB) or complete right bundle branch block (RBBB) patterns (14% at 2 weeks, 16% at 1 month, and 22% at 1 year). In patients with hemodynamic measurements available approximately at the time of the ECG recording 1 year following transplantation, there was a significant correlation between the presence of IRBBB and RBBB patterns and somewhat higher levels of right atrial mean pressure (6.8 versus 3.9 mm Hg, p = 0.01), pulmonary artery systolic pressure (32.5 versus 24.5 mm Hg, p = 0.001) and diastolic pressure (16.2 versus 11.2 mm Hg, p = 0.004), and right ventricular systolic pressure (31.4 versus 26.9 mm Hg, p = 0.019) and pulmonary artery wedge mean pressure (11.3 versus 7.9 mm Hg, p = 0.010). Repolarization changes were also common but decreased in frequency over time (78% at 2 weeks to 34% at 1 year) and did not correlate with the presence or absence of rejection. We conclude that ECG abnormalities in heart transplant recipients are generally mild and that IRBBB and RBBB patterns correlate with increased right heart pressures.

Atrial Function↗
PubMed1990

Cardiac transplantation in patients with preexisting neoplastic diseases.

Cardiac transplantation has traditionally been reserved for individuals with end-stage congestive heart failure (CHF) in whom there is no history of other life-threatening systemic disorders. In most transplant centers, patients with a history of malignancy and severe heart failure have not been considered acceptable candidates for cardiac transplantation. In the last 4 years at Stanford University Medical Center, 8 cardiac transplants have been performed in 7 patients with a history of neoplastic disease. Six of these patients had already received treatment for lymphoproliferative disorders and in 1 case, a patient underwent a transplant after treatment for adenocarcinoma of the colon. Six of the 7 patients were discharged from the hospital and in that group, the 1-year posttransplant survival rate was 71%. This was comparable to an overall 1-year survival rate of 80% for patients undergoing a cardiac transplant at our center during the same period of time. At follow-up averaging over 2 years, there has been 1 case of recurrent neoplasia. One patient with evidence of radiation-induced pulmonary damage died of respiratory failure 2 days after transplantation. One patient required retransplantation because of intractable rejection and subsequently died from infectious complications. Immunosuppressive therapy in these patients has not been associated with an increased risk for neoplastic recurrence or for the development of posttransplant lymphoproliferative disorders. The current study demonstrates that in a carefully selected group, previously treated neoplastic disease should not represent a contraindication to cardiac transplantation.

Adolescent↗
PubMed1990

Long-term cardiopulmonary function after human heart-lung transplantation.

We present cardiac and pulmonary function data obtained at serial annual reviews in 21 heart-lung transplant (HLT) recipients followed for up to four years postoperatively, reflecting the entire Stanford experience as of June 1987. A total of 50 cardiac catheterisation procedures and endomyocardial biopsies yielded the following results: rejection on biopsy (0/50) (0% of patients), angiographic coronary artery disease (1/50) (5%), pulmonary hypertension (2/50) (10%), elevated pulmonary vascular resistance (PVR) (1/50) (5%), and low cardiac index (CI) (4/50) (14%). Systemic hypertension was common, with an elevated systemic vascular resistance (SVR) (26/44) (76%) and an elevated mean aortic pressure (MAP) (22/44) (67%). Pulmonary function testing frequently revealed abnormalities. Airflow limitation was manifested by a reduction in both FEV1/FVC ratio (17/50) (52%) and FEF25-75 (30/50) (71%), and was often associated with arterial hypoxaemia (13/50) (52%). Subsequently, five patients with these findings have died with obliterative bronchiolitis (OB), one underwent retransplantation for OB, six have stable OB, and one has progressive OB. Length of survival was highly correlated with the resting PaO2 at the first annual review (r = 0.99) (p less than 0.001), and, to a lesser degree, on the reduction in FEF25-75 (r = 0.73) (p less than 0.05) and FEV1/FVC ratio (r = 0.77) (p less than 0.05). Resting PaO2 was determined by ventilatory (r = 0.80) (p less than 0.001) rather than circulatory factors and all patients with airflow limitation who died had OB at post-mortem examination. These results support the continued study of HLT as a therapeutic modality for selected patients with irreversible pulmonary hypertension. They demonstrate that, in the absence of severe OB, haemodynamics, cardiac function, and coronary patency are preserved for several years after HLT. Whereas the value of regular pulmonary function testing has become evident, there does not appear to be a clinical need for annual surveillance with invasive cardiac procedures in long-term survivors of HLT.

Adolescent↗
PubMed1990

Progressive coronary luminal narrowing after cardiac transplantation.

Accelerated coronary disease is a major factor limiting long-term survival in cardiac transplant recipients. Coronary angiography was obtained a mean of 5.1 weeks posttransplantation and annually thereafter. Replicate projections recorded after nitroglycerine administration were quantitated using computer-assisted edge detection. Five hundred and fifteen coronary segments in 25 patients having 1-year follow-up and 353 segments in 18 patients reaching 2-year follow-up were compared with baseline angiograms. Significant change was defined as +/- 0.10 mm, equal to 3.8% change in diameter based on three standard deviations obtained from estimation of measurement error. Mean coronary diameter fell from 2.44 +/- 0.26 mm at baseline to 2.21 +/- 0.34 mm (p less than 0.001) at 1-year follow-up. This rate of diameter decline was 20-fold more rapid during the initial posttransplantation year than the rate of change of visually normal segments in nontransplant patients with coronary atherosclerosis elsewhere. There was no significant drop in mean diameter between the first and second year in those patients who had second-year studies. Decrease in absolute diameter for vessels greater than 2.9 mm significantly exceeded diameter reduction for smaller vessels but did not differ when considered as a ratio of vessel diameter. In 21 of 25 patients, mean coronary diameter reduction exceeded the three-standard deviation threshold at their last angiogram, but only two of these patients had visually detectable transplant coronary disease.

Cineangiography↗
PubMed1990

Go team.

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Female↗
PubMed1989

Acute myocardial infarction in cardiac transplant recipients.

To characterize the clinical and pathologic features of acute myocardial infarction (AMI) in cardiac transplant recipients, 22 Stanford patients who had 25 documented infarcts at a mean of 3.86 years after transplantation were reviewed. Symptoms included chest pain (2), arm pain (3), weakness (16), dyspnea (11) and palpitations (8). Three episodes were clinically silent, detected only as new electrocardiographic changes during routine follow-up. Of 18 patients hospitalized with symptoms, only 7 had electrocardiographic changes of typical Q-wave AMI; 5 had nonspecific ST-segment changes and 2 had no documented changes. Two had old Q waves. Twelve of the 18 were misdiagnosed at admission as having infection or congestive heart failure. Serial creatine phosphokinase levels were obtained in 13 patients, and values were elevated in 8. Six of 25 AMI episodes were associated with development of congestive heart failure and 4 others led to development of cardiogenic shock. Seven patients died during the acute phase of infarction, 12 were retransplanted from 2 days to 6 months after infarct and 1 died suddenly after discharge. Two healed myocardial infarctions of unknown duration were found at autopsy or on explantation in patients not clinically suspected of having an AMI. All infarcts occurred in patients known to have angiographic evidence of transplant coronary artery disease, based on annual coronary arteriography. At autopsy or explantation all hearts were found to have characteristic diffuse concentric coronary artery narrowing, and 4 (18%) had an unusual pattern of multiple foci of nontransmural AMI.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

Frequency of familial nature of dilated cardiomyopathy and usefulness of cardiac transplantation in this subset.

A familial etiology was identified on the basis of family history in 16 (8.75%) of 184 patients undergoing cardiac transplantation at Stanford for endstage dilated cardiomyopathy (DC). These 16 patients, from 11 families, included 5 sibling pairs. To help determine optimal management of such patients, their case histories and posttransplant courses were reviewed. Mean age of patients at presentation was 23 +/- 15 years. In sibling pairs, duration of symptoms from onset to diagnosis was 14 +/- 5 weeks for the first sibling, but only 4 +/- 2 weeks for the second. Progressive cardiac enlargement was documented radiographically in siblings of transplant recipients in 2 families before the onset of symptoms. The posttransplant course with regard to rejection incidence, infectious complications, coronary artery disease and malignancy was similar to that of the 168 patients with nonfamilial DC. Actuarial survival at 5 years after transplantation was 80%. Thirteen patients (including all sibling pairs) are alive 1 to 11 years after transplantation. Sepsis was the cause of death in 3 patients, occurring during the early postoperative period in 2 and following retransplantation for graft atherosclerosis 7 years after the initial transplant in the third patient. Thus, diagnosis of DC in childhood or adolescence mandates evaluation and surveillance of family members, because this disease can progress rapidly. The favorable results of cardiac transplantation for familial DC suggest that it should be promptly considered for such patients with end-stage disease.

Adolescent↗
PubMed1989

A hemodynamic and Doppler echocardiographic study of ventricular function in long-term cardiac allograft recipients. Etiology and prognosis of restrictive-constrictive physiology.

Conventional hemodynamic measurements and Doppler echocardiography were used to assess ventricular physiology of the human cardiac allograft and to examine the influence of pertinent clinical factors on chronic myocardial performance. Sixty-four patients (18-55 years old; mean, 39 years) undergoing routine annual hemodynamic assessment were studied. Blood-flow velocity properties across the mitral, tricuspid, and aortic valves were analyzed from Doppler ultrasound recordings. Ten of these patients had elevated diastolic pressures associated with a sharp early diastolic dip followed by an exaggerated and abrupt rise in pressure, consistent with restrictive-constrictive ventricular physiology. Left ventricular dP/dt and stroke volume were lower in these patients compared with the other 54 patients. Doppler echocardiographic indexes of left ventricular filling and ejection in these 10 patients differed significantly. Isovolumic relaxation time and pressure half-time were shorter, peak early mitral and tricuspid flow velocities were higher, and mean aortic flow velocity and acceleration were lower. A higher rejection incidence was the only demonstrable clinical factor associated with impaired ventricular function. Doppler echocardiography may, therefore, noninvasively identify patients with hemodynamic evidence of restrictive-constrictive physiology. This abnormality occurs in approximately 15% of allograft recipients, is associated with impaired systolic performance, and may be related to rejection incidence.

Adolescent↗
PubMed1989

Increasing pericardial effusion in cardiac transplant recipients.

Although pericardial effusion after cardiac surgery is frequent and usually benign, its etiology and prognosis after cardiac transplantation are unknown. During 1 year (1985-1986), 12 of our current transplant population (total, 189) developed moderate or large pericardial effusions confirmed by two-dimensional echocardiography. These effusions occurred within 1 month of transplantation in 10 patients and at 3 months and 4.5 years in the other two. Pericardiocentesis was performed because of clinical evidence of increasing effusions in eight patients, with demonstrable hemodynamic compromise secondary to tamponade in five. Pericardial fluid was sterile in all but one. Endomyocardial biopsy at the time of increasing effusion revealed moderate acute rejection in five patients, mild rejection in three, and no rejection in four. All three patients with mild rejection had moderate acute rejection on subsequent biopsy performed within 7 days. In two of the four with no rejection, repeat biopsy within 5 days showed moderate acute rejection; in a third, moderate rejection was present on biopsy performed 14 days later. Legionella dumoffii was isolated from the pericardial fluid of the fourth patient, whose subsequent biopsies never showed rejection. Three of the 12 patients developed progressive ventricular dysfunction sufficiently severe to require retransplantation. One patient died suddenly 12 months after transplantation, and autopsy examination revealed severe coronary artery disease. Two died of sepsis within 3 months of transplantation. Intense inflammatory infiltrates and thickening of the pericardium and epicardium were characteristically present in explanted and autopsy hearts.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

Prevalence of accelerated coronary artery disease in heart transplant survivors. Comparison of cyclosporine and azathioprine regimens.

Rapid development of diffuse, occlusive coronary artery disease in the cardiac allograft has emerged as a major limiting factor for long-term survival after transplantation. Prior multivariate analyses have failed to identify any strong predictors of this disease. We retrospectively reviewed serial annual coronary angiograms to assess the prevalence of transplant coronary artery disease. A total of 103 patients treated initially with azathioprine-based therapy were compared with a later cohort of 78 patients for whom cyclosporine was the basis of immunosuppressive therapy. The percent of patients free of angiographically visible transplant coronary artery disease at 1 year was 89% for the azathioprine group versus 86% for the cyclosporine group. At 3 years, 74% of the azathioprine group versus 63% of the cyclosporine group were free of visible disease (p = NS). By the fifth postoperative year, 58% of azathioprine-treated and 50% of cyclosporine-treated patients were free of transplant coronary artery disease (p = NS). The mean number of rejection episodes in the first year after transplantation was 2.0 for cyclosporine patients versus 2.5 for azathioprine patients. The azathioprine and cyclosporine patients were compared with respect to a variety of baseline and clinical follow-up measurements that might influence the development of coronary artery disease. Patients in the cyclosporine group had higher blood pressure (135/94 versus 123/85 mm Hg, p less than 0.001) and were receiving lower maintenance prednisone doses. This study demonstrates that improved cyclosporine immunosuppression does not decrease the time-related prevalence of transplant coronary artery disease.

Azathioprine↗
PubMed1988

Drug management of the cardiac transplant patient.

Drug or pharmacologic management of patients with cardiac allografts is an area of clinical cardiology that is quite different from most pharmacological management involved in caring for patients with cardiac disease. In transplant patients one is dealing with a heart that is not stunned, ischemic, infarcted, hypertrophied, dilated, or in any way weak or structurally abnormal. The patient has a perfectly healthy heart, usually chronologically younger than the patient, the only flaw of which is its antigenic dissimilarity from tissue of the patient. This dissimilarity, of course, leads to the need to suppress the normal immune response and make the patient at least relatively immunologically tolerant of his or her solid organ allograft. Problems inherent in the induction and maintenance of immune tolerance in cardiac allograft patients are no different than those encountered in the more widely practiced field of renal transplantation. The major obvious difference is that of the more disastrous consequence of graft "loss" in cardiac transplant recipients since no cardiac equivalent of chronic hemodialysis exists to be resorted to. Thus, immunosuppressive regimens used in cardiac transplant programs tend to err (if they err) on the side of heavier suppression and accept the consequences of this choice.

Heart Transplantation↗