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Biomedical subjects

S A Hunt

Publications and source records attributed to S A Hunt.

At least 37 records · Page 2Linked to original sources
PubMed1996

Early Doppler echocardiographic dysfunction is associated with an increased mortality after orthotopic cardiac transplantation.

BACKGROUND: Doppler echocardiographic (DE) diastolic dysfunction has been correlated with rejection after orthotopic cardiac transplantation (Tx). However, the relationship of early diastolic dysfunction to late outcome is unknown. The purpose of this study was to assess the correlation between early DE diastolic dysfunction and outcome after heart Tx. METHODS AND RESULTS: Of 133 patients undergoing heart Tx between October 1990 and April 1994, 83 were identified with > or = 4 routine DE performed during the first 6 months. Assessment of diastolic function included measurement of isovolumic relaxation time (IVRT), pressure half-time (PHT), and peak early mitral inflow velocity (M1). Diastolic dysfunction was defined as a decrease of 15% from baseline (IVRT and PHT) or an increase of 20% (M1). A mean dysfunction score (MDS) was calculated for each patient (number of episodes of dysfunction by Doppler total number of echocardiograms performed). The population diastole MDS was determined and two groups established (group 1, MDS < mean; group 2, MDS > mean). Actuarial survival, rejection, and transplant coronary artery disease (TxCAD) were compared between groups. Actuarial survival was significantly reduced in patients with greater early diastolic dysfunction (P < .05). There were 17 deaths overall: 5 in group 1 (mean, 786 days) and 12 in group 2 (mean, 384 days). There were no significant differences in treated rejection episodes, actuarial freedom from rejection or TxCAD, immunosuppression, sex, donor age, donor ischemic time, or cytomegalovirus between the two groups. CONCLUSIONS: Diastolic dysfunction within 6 months of transplant was associated with an increased late mortality.

Adult↗
PubMed1996

Are heart-lung transplant recipients protected from developing transplant coronary artery disease? A case-matched intracoronary ultrasound study.

BACKGROUND: Accelerated coronary artery disease is a major cause of mortality in heart transplant recipients; however, it does not appear to play a major role in the clinical outcome of heart-lung transplant recipients. The purpose of this study was to determine whether the incidence and severity of transplant coronary artery disease as detected by intracoronary ultrasound in heart-lung transplant recipients are less than those encountered in heart transplant recipients. METHODS AND RESULTS: We studied the left anterior descending coronary artery with the use of intracoronary ultrasound imaging in 22 heart-lung transplant recipients at the time of their routine annual coronary angiogram. Twenty-two heart transplant recipients were case matched for number of years after transplant at ultrasound study, recipient age, donor age, and diagnosis of nonischemic cardiomyopathy. Mean intimal area, intimal index, Stanford class, and incidence of at least moderate disease (Stanford class > or = 3) were measured and calculated in each group and then compared between the two groups. Mean intimal area (1.6 +/- 2.5 versus 3.8 +/- 2.8 mm2), mean intimal index (0.07 +/- 0.10 versus 0.22 +/- 0.14), mean Stanford class (1.7 +/- 1.0 versus 2.7 +/- 1.2), and incidence of Stanford class > or = 3 (14% versus 45%) were significantly lower in the heart-lung transplant recipient group. CONCLUSIONS: The incidence and severity of transplant coronary artery disease are much less in patients receiving heart-lung transplants than in those receiving heart transplants alone.

Adult↗
PubMed1996

Induction of nitric oxide synthase in the human cardiac allograft is associated with contractile dysfunction of the left ventricle.

BACKGROUND: The mechanisms underlying cardiac contractile dysfunction after transplantation remain poorly defined. Previous work has revealed that inducible nitric oxide synthase (iNOS) is expressed in the rat heterotopic cardiac allograft during rejection; resultant overproduction of nitric oxide (NO) might cause cardiac contractile dysfunction via the negative inotropic and cytotoxic actions of NO. In this investigation, we tested the hypothesis that induction of iNOS may occur and be associated with cardiac allograft contractile dysfunction in humans. METHODS AND RESULTS: We prospectively studied 16 patients in the first year after cardiac transplantation at the time of serial surveillance endomyocardial biopsy. Clinical data, the results of biopsy histology, and echocardiographic and Doppler evaluation of left ventricular systolic and diastolic function were recorded. Total RNA was extracted from biopsy specimens, and mRNA for beta-actin, detected by reverse transcription-polymerase chain reaction (RT-PCR) using human specific primers, was used as a constitutive gene control; iNOS mRNA was similarly detected by RT-PCR using human specific primers. iNOS protein was detected in biopsy frozen sections by immunofluorescence. Myocardial cGMP was measured by radioimmunoassay, and serum nitrogen oxide levels (NOx = NO2 + NO3) were measured by chemiluminescence. iNOS mRNA was detected in allograft myocardium at some point in each patient and in 59 of 123 biopsies (48%) overall. In individual patients, iNOS mRNA expression was episodic and time dependent; the frequency of expression was highest during the first 180 days after transplant (P = .0006). iNOS protein associated with iNOS mRNA was detected by immunofluorescence in cardiac myocytes. iNOS mRNA expression was not related to the ISHLT histological grade of rejection or to serum levels of NOx but was associated with increased levels of myocardial cGMP (P = .01) and with both systolic (P = .024) and diastolic (P = .006) left ventricular contractile dysfunction measured by echocardiography and Doppler. CONCLUSIONS: These data support a relation between iNOS mRNA expression and contractile dysfunction in the human cardiac allograft.

Adolescent↗
PubMed1996

Coronary artery intimal thickening in the transplanted heart. An in vivo intracoronary untrasound study of immunologic and metabolic risk factors.

This study examined the hypothesis that immunologic factors are the major correlates of coronary artery intimal thickening and luminal stenosis. The study population included 116 adult heart transplant recipients with a mean age of 44.7 +/- 12.0 years (89 men and 27 women) undergoing annual coronary angiography and intracoronary ultrasound 3.4 +/- 2.7 (range, 1.0-14.6) years after transplantation. Mean intimal thickness was obtained from several distinct sites along the left anterior descending and/or left circumflex coronary artery by intracoronary ultrasound. Coronary artery stenosis defined by angiography was classified as mild (< 30% luminal stenosis), moderate (> or = 30-70% luminal stenosis), or severe (> 70% luminal stenosis or diffuse pruning of distal vessels). Prevalence of any transplant coronary artery disease (TxCAD) was 85% by intracoronary ultrasound and 15% by angiography. By multiple regression analysis, only average fasting plasma triglyceride level (P < 0.006) and average weight (P < 0.007) were significantly correlated with severity of intimal thickening (R = 0.54, P < 0.0001). Donor age (P < 0.006) and average fasting plasma triglyceride level (P < 0.009) were significantly correlated with stenosis by angiography. Correlation of multiple immunologic and metabolic factors with intimal thickness by univariate analysis suggests a multifactorial etiology for TxCAD. Among the multiple univariate correlates of TxCAD, higher fasting plasma triglyceride levels and body weight are the only independent correlates of TxCAD. The absence of acute rejection as an independent predictor of intimal thickening suggests that mechanisms beyond those mediating typical cellular rejection should be targeted for advancing our understanding of Tx-CAD.

Adult↗
PubMed1996

Early development of accelerated graft coronary artery disease: risk factors and course.

OBJECTIVES: This study assessed the time of first appearance of angiographic graft coronary artery disease in relation to clinical and laboratory variables and clinical events in heart transplant recipients. BACKGROUND: Graft coronary artery disease is the main factor limiting long-term survival after heart transplantation, and it is important to understand its natural history. METHODS: One hundred thirty-nine consecutive patients who developed angiographic coronary artery disease after heart transplantation were classified according to early (< or = 2 years) versus late (> 2 years) posttransplantation initial detection of coronary artery disease. These subgroups were analyzed for differences in clinical and laboratory demographics, incidence of progression to ischemic events and incidence of antecedent cytomegalovirus infection. RESULTS: The early-onset group (64 patients) had more rapid progression to ischemic events than the late-onset group (75 patients), with 59% of the late group and only 35% of the early group free from ischemic events by 5 years after initial detection (p = 0.02), but there were no significantly correlated clinical or laboratory predictors of ischemic events. The early group had a significantly higher incidence of antecedent cytomegalovirus infection. CONCLUSIONS: We conclude that 1) accelerated graft coronary artery disease develops at variable times after heart transplantation; 2) the early appearance of graft coronary artery disease may be a marker of intrinsically more aggressive disease; 3) cytomegalovirus infection is associated with earlier onset of graft coronary artery disease. Patients with early development of graft coronary artery disease should potentially be given priority for interventional strategies as they are developed.

Adult↗
PubMed1995

Prognostic importance of intimal thickness as measured by intracoronary ultrasound after cardiac transplantation.

BACKGROUND: Although intracoronary ultrasound (ICUS) has been validated for the early detection of transplant coronary artery disease (TxCAD), the prognostic importance of findings detected by this new imaging technique is unknown. METHODS AND RESULTS: This study examined the relation of clinical outcome in 145 heart transplant recipients (mean age, 45.1 +/- 11.1 years) with the amount of intimal thickness measured by ICUS during routine annual coronary angiography 1 to 10 years (mean, 3.1 +/- 2.2 years) after transplantation. From published autopsy data, a mean intimal thickness of > 0.3 mm was considered significant. During a mean follow-up time of 48.2 +/- 10.2 months, 23 deaths (12 cardiac) occurred, and 6 patients required retransplantation. Angiographic TxCAD developed in 22 of 125 patients (17.6%) in the subgroup with normal angiograms at the time of ICUS and a follow-up annual angiographic study. In the total population and the subgroup, mean intimal thicknesses of > 0.3 and < or = 0.3 mm, respectively, were associated with significantly inferior 4-year actuarial overall survival (73% versus 96%, P = .005; 72% versus 92%, P = .05), cardiac survival (79% versus 96%, P = .005; 80% versus 98%, P = .04), and freedom from cardiac death and retransplantation (74% versus 98%, P < .0001; 70% versus 96%, P = .001). In addition, ICUS predicted freedom from development of subsequent angiographic TxCAD in the subgroup that was initially normal (26% versus 72%, P = .02). A mean intimal thickness by ICUS of > 0.3 mm was associated with inferior clinical outcome regardless of the presence of angiographic TxCAD and predicted the development of subsequent angiographic TxCAD. Despite significantly longer duration after transplantation, higher rejection incidence, and lower average daily cyclosporine dose, none of these covariates were independent risk factors for outcome. CONCLUSIONS: These findings confirm the prognostic importance of mean intimal thickening of > 0.3 mm in heart transplant recipients and suggest that these patients should be candidates for early interventional strategies.

Coronary Disease↗
PubMed1995

Correlation of donor characteristics with transplant coronary artery disease as assessed by intracoronary ultrasound and coronary angiography.

The mechanisms responsible for transplant coronary artery disease (CAD) and its predisposing factors remain incompletely understood. The influence of donor characteristics as predisposing factors has not been studied systematically. We examined the correlation of donor demographic, clinical, and immunologic parameters with transplant CAD assessed by both intracoronary ultrasound (ICUS) and coronary angiography in 116 heart transplant recipients (age 44.7 +/- 12.0 years) studied 3.4 years (range 1.0 to 14.6) after transplantation. Quantitative ultrasound data were obtained by calculating mean intimal thickness from several distinct coronary sites. Coronary angiograms were categorized visually as normal or showing any transplant CAD. By multivariate regression analysis, donor undersize of > 20% of recipient weight (p < 0.02) and duration after transplantation (p < 0.005) were independently correlated with the amount of ICUS intimal thickness (r = 0.36, p = 0.0007), and older donor age with angiographic evidence for the disease (r = 0.34, p < 0.006). In a subgroup analysis of the 39 patients studied 1 year after transplantation, white donor race (p < 0.05), fewer human leukocyte antigen-DR mismatches (p < 0.002), shorter ischemic time (p < 0.04), and donor smoking history (p < 0.02) were independent predictors for severity of ICUS intimal thickening (r = 0.92, p = 0.0009); higher donor age (p < 0.006) and higher arterial partial pressure of oxygen (p < 0.003) were independent predictors for angiographic disease (r = 0.67, p < 0.002). In conclusion, donor characteristics may contribute to the probably multifactorial pathogenesis of transplant CAD.

Adult↗
PubMed1995

Cardiac allograft vascular disease. Relationship to microvascular cell surface markers and inflammatory cell phenotypes on endomyocardial biopsy.

BACKGROUND: Cardiac allograft vascular disease is characterized by accelerated and diffuse intimal proliferation involving both the microvasculature and epicardial vessels. Because in vivo documentation of this complication is now possible with intracoronary ultrasound imaging, we can examine the relationship of intimal proliferation to markers of immunity and endothelial activation. We hypothesize that alterations of microvascular cell surface markers likely mirror changes in the epicardial vessels that may be important in the pathophysiology of intimal proliferation. METHODS AND RESULTS: Forty-three heart transplant patients were examined by intracoronary ultrasound more than 1 year after transplantation, and these images were analyzed to obtain mean intimal thickness and intimal thickness class (I through IV), calculated from the mean thickness and circumferential involvement. Right ventricular endomyocardial biopsies obtained at the time of intracoronary ultrasound were examined by immunohistochemistry to detect microvascular expression of histocompatibility leukocyte antigen (HLA) classes I and II (HLA ABC, DR, DP, and DQ); endothelial-specific antigen detected by the monoclonal antibody E 1.5; intercellular adhesion molecules (ICAM-1); CD4+ and CD8+ lymphocytes and macrophages (CD 14+). Microvascular antigen expression was graded 1 through 5 on the basis of the diffuseness of positive staining. The number of each inflammatory cell phenotype present per high-power field was counted. By ANOVA, scores for HLA DR, HLA DQ, and E1.5 expression were lower in intimal thickness classes II, III, and IV compared with class I. This inverse relationship was significant by linear regression analysis of mean intimal thickness. Inflammatory cells were not significantly correlated with intimal thickening. Rejection incidence was higher, and time since transplantation longer, in intimal thickness classes II, III, and IV compared with class I. CONCLUSION: Transplant coronary artery intimal proliferation is associated with alteration of microvascular endothelial cell surface markers. These changes in cell surface antigen expression could provide the substrate for coronary artery intimal proliferation and narrowing.

Adult↗
PubMed1995

Incidence and severity of transplant coronary artery disease early and up to 15 years after transplantation as detected by intravascular ultrasound.

OBJECTIVES: The purpose of this study was to quantify the severity of transplant coronary artery disease and to assess lesion characteristics early and up to 15 years after heart transplantation by using intracoronary ultrasound. BACKGROUND: Intravascular ultrasound has the ability to measure the components of the arterial wall and has been shown to be a sensitive method for detection of transplant coronary artery disease. METHODS: A total of 304 intracoronary ultrasound studies were performed in 174 heart transplant recipients at baseline and up to 15 (mean 3.3 +/- 0.2) years after transplantation. Mean intimal thickness and an intimal index were calculated, and lesion characteristics (eccentricity, calcification) were assessed for all coronary sites imaged (mean 3.0 +/- 0.1 sites/study). The Stanford classification was used to grade lesion severity. RESULTS: Compared with findings in patients studied at baseline (< 2 months after transplantation, n = 50), mean intimal thickness (0.09 +/- 0.02 vs. 0.16 +/- 0.02 mm, p < 0.01), intimal index (0.07 +/- 0.01 vs. 0.14 +/- 0.02, p < 0.01) and mean severity class (1.5 +/- 0.2 vs. 2.3 +/- 0.2, p < 0.01) were significantly higher at year 1 (n = 52) after transplantation. Thereafter, all three variables further increased over time and reached highest values between years 5 and 15. Calcification of lesions was detected in 2% to 12% of studies up to 5 years after transplantation, with a significant increase to 24% at years 6 to 10 (p < 0.05). CONCLUSIONS: Severity of transplant coronary artery disease appeared to progress with time after transplantation in this cross-sectional study. This characteristic was most prominent during the 1st 2 years after transplantation, whereas calcification of plaques occurred to a significant extent only later in the process. These data may serve as a reference for comparison of intravascular ultrasound findings in other studies of patients with transplant coronary artery disease.

Adult↗
PubMed1995

Clinical outcome of interval cadaveric renal transplantation in cardiac allograft recipients.

The introduction of cyclosporine into widespread clinical use has resulted in improved patient survival following cardiac transplantation. As a result of increased numbers of cardiac transplants, the inherent nephrotoxicity of cyclosporine, and prolonged patient survival, cardiac transplant recipients commonly present with renal dysfunction. In the subgroup who ultimately develop end-stage renal disease (ESRD), therapeutic options include renal transplantation. However, the clinical course associated with this treatment modality is unknown. From 1980 to 1993, 430 cardiac transplants were performed with cyclosporine-based immunosuppression at the Standard University Medical Center. Fourteen (3.3%) patients developed ESRD, requiring chronic dialysis or renal transplantation. The cause of ESRD was cyclosporine nephropathy (13/14; 93%) and glomerulonephritis (1/14; 7%). The average time interval to the development of ESRD was 82 +/- 42 months. Nine patients underwent renal transplantation. During the period of followup (38 +/- 27 months; range 6-89 months) after renal transplantation, cardiac function remained stable. There were no episodes of primary nonfunction of the renal allograft. Patient and renal allograft survival was 89% at both 1 and 3 years after renal transplant. Average serum creatinine was 1.3 +/- 0.6 mg/dl at 1 year and 1.6 +/- 0.8 mg/dl at 3 years post-transplant. The incidence of infectious complications was not statistically different when compared to that of the heart transplant controls and that of a group of cadaveric renal transplant controls (n = 20). Surprisingly, the incidence of renal allograft rejection in the heart transplant patients was 10-fold less than that of the renal transplant controls (0.006 +/- 0.02/patient-year vs. 0.062 +/- 0.05/patient-year; p < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Metabolic risk factors for atherosclerosis in heart transplant recipients.

Development of coronary artery disease (CAD) in the cardiac allograft limits long-term survival after heart transplantation. Previous studies, focusing on lipoprotein metabolism, have paid little attention to changes in glucose and insulin metabolism that increase the risk of CAD in these patients. To address this issue, plasma glucose and insulin responses to an oral glucose load and lipid and lipoprotein concentrations were measured in male normal volunteers (n = 40) and cardiac transplant recipients with pretransplant diagnoses of either idiopathic cardiomyopathy (n = 24) or ischemic heart disease (n = 28), matched for age and body mass index. Patients with a pretransplant diagnosis of ischemic heart disease had higher plasma glucose and insulin concentrations in response to oral glucose as well as higher fasting plasma triglyceride, cholesterol, and low-density lipoprotein cholesterol concentrations than did the control group (p < 0.005 to p < 0.001). In addition, high-density lipoprotein cholesterol concentrations were lower and the ratio of cholesterol to high-density lipoprotein cholesterol higher than control values in those with a pretransplant diagnosis of ischemic heart disease (p < 0.001). Values for almost all variables were intermediate in patients with a pretransplant diagnosis of idiopathic cardiomyopathy and in most instances were significantly different from both. Thus, male cardiac transplant recipients are dyslipidemic, relatively glucose intolerant, and hyperinsulinemic compared to normal volunteers. These changes, observed in patients with a pretransplant diagnosis of either ischemic heart disease or idiopathic cardiomyopathy, emphasize the important role of immunosuppression in the development of metabolic risk factors for CAD in these individuals.

Blood Glucose↗
PubMed1994

Long-term outcome after heart transplantation for peripartum cardiomyopathy.

To elucidate the long-term outcome and frequency of complications after heart transplantation for peripartum cardiomyopathy (PPCM), we compared the courses of eight consecutive patients undergoing transplantation for PPCM with those of nine female age-matched control subjects undergoing transplantation for idiopathic dilated cardiomyopathy (IDCM). No significant differences could be found in baseline variables between the two groups with the exception of the number of pregnancies (2.5 +/- 1.5 vs 0, p = 0.0002). Two patients in each group died during the first 6 months after transplantation, and one in each group died later. Actuarial survival rates were 75% +/- 15% and 78% +/- 14% (p = NS) at 1 year and 60% +/- 18% and 78% +/- 14% (p = NS) at 5 years in PPCM and IDCM patients, respectively. Linearized rejection rates during the first 3 months were 1.85 +/- 0.56 and 1.91 +/- 0.49 (p = NS) and during the second 3 months were 0.18 +/- 0.18 and 0.45 +/- 0.26 (p = NS), respectively. Similarly no significant differences in linearized infection rates were found. Among patients surviving more than 6 months after transplantation, after a mean follow-up period of 4.5 +/- 3.1 years for those with PPCM and 7.8 +/- 3.2 years for those with IDCM, 83% and 100%, respectively, were rehabilitated; hemodynamic findings were normal in all patients and the frequency of other transplant-associated complications was similar in both groups. In conclusion, heart transplantation is a valuable option for patients with PPCM and severe congestive heart failure that is unresponsive to conventional treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Actuarial Analysis↗
PubMed1994

Cardiac transplantation: the Stanford experience in the cyclosporine era.

We analyzed our experience with 496 patients who underwent primary cardiac transplantation since the introduction of cyclosporine immunosuppression (Dec. 16, 1980, to Jan. 7, 1993). There were 388 male and 108 female patients. Mean recipient age was 40 +/- 16 years (range 0.1 to 70 years, median 44 years). Recipient diagnoses included coronary disease in 188, idiopathic cardiomyopathy in 196, viral cardiomyopathy in 35, and congenital heart disease in 28 patients. Donor age was 25 +/- 10 years (range 1 to 53 years, median 24 years). Graft ischemic time was 148 +/- 57 minutes (range 38 to 495 minutes, median 149 minutes). Operative mortality (hospital death) rate was 7.9% +/- 1.3% (70% confidence intervals). Multivariate logistic regression analysis revealed that (higher) pulmonary vascular resistance and gender (female) were the only independent predictors of hospital death (p < 0.05). Actuarial survival estimates for all patients at 1, 5, and 10 years are 82% +/- 1.7% (83% +/- 1.8% adult, 77% +/- 5.2% pediatric), 61% +/- 2.5% (65% +/- 2.5% adult, 64% +/- 6.6% pediatric), and 41% +/- 3.7% (40% +/- 4% adult, 54% +/- 8.6% pediatric), respectively. For 232 patients treated with triple-drug immunosuppression and induction with OKT3 since 1987, survival estimates at 1 and 5 years are 82% +/- 2.6% and 67% +/- 3.7%, respectively. Causes of death for the entire group were rejection in 29 (14% of deaths), infection in 69 (34%), graft coronary disease in 36 (18%), nonspecific graft failure in 6 (3%), malignancy in 19 (10%), stroke in 6 (3%), pulmonary hypertension in 6 (3%), and other causes in 30 (15%) patients. Actuarial freedom from rejection at 3 months, 1 year, and 5 years was 21% +/- 1.9%, 14% +/- 1.7%, and 7.2% +/- 1.5%, respectively (+/- 1 standard error of the mean). Estimates of freedom from rejection-related death at 1, 5, and 10 years were 96% +/- 1%, 93% +/- 1.4%, and 93% +/- 1.4%, respectively. Actuarial freedom from any infection at 3 months and at 1 and 5 years was 40% +/- 2.3%, 27% +/- 2.1%, and 15% +/- 2.0% and from infection-related death, 95% +/- 1.0%, 93% +/- 1.2%, and 85% +/- 1.9%, respectively. Actuarial freedom from (angiographic or autopsy proved) graft coronary artery disease at 1, 5, and 10 years was 95% +/- 1.2%, 73% +/- 2.7%, and 65% +/- 3.6% and from coronary disease-related death or retransplantation 98% +/- 0.7%, 84% +/- 2.2%, and 66% +/- 4.3%, respectively.(ABSTRACT TRUNCATED AT 400 WORDS)

Actuarial Analysis↗
PubMed1993

A preliminary study of diltiazem in the prevention of coronary artery disease in heart-transplant recipients.

BACKGROUND: Accelerated coronary artery disease is a major cause of late morbidity and mortality among heart-transplant recipients. Because calcium-channel blockers can suppress diet-induced atherosclerosis in laboratory animals, we assessed the efficacy of diltiazem in preventing coronary artery disease in transplanted hearts. METHODS: Consecutive eligible cardiac-transplant recipients were randomly assigned to receive diltiazem (n = 52) or no calcium-channel blocker (n = 54). Coronary angiograms obtained early after cardiac transplantation and annually thereafter were used for the visual assessment of the extent of coronary artery disease. The average diameters of identical coronary artery segments were measured on the angiograms obtained at base line and at the first and second follow-up examinations. RESULTS: In the 57 patients who had all three angiograms, the average coronary artery diameter (+/- SD) 0.27 decreased in the group that received no calcium-channel blocker from 2.41 +/- 0.27 mm at base line to 2.19 +/- 0.28 mm at one year, and to 2.22 +/- 0.26 mm at two years (P < 0.001 for both years). The average diameter in the diltiazem group changed little from the base-line value of 2.32 +/- 0.22 mm (2.32 +/- 0.27 mm at one year and 2.36 +/- 0.22 mm at two years). The average change in the diameter of the segment differed significantly between the two treatment groups (P < 0.001), and the estimated effect of treatment changed only negligibly after adjustment for other relevant clinical variables. New angiographic evidence of coronary artery disease developed in 14 patients not given calcium-channel blockers, as compared with 5 diltiazem-treated patients (P = 0.082). Coronary stenoses greater than 50 percent of the luminal diameter developed in seven patients not given calcium-channel blockers, as compared with two patients given diltiazem; death due to coronary artery disease or retransplantation occurred in five patients in the group that did not receive calcium-channel blockers and none of those who received diltiazem. CONCLUSIONS: Our preliminary results suggest that diltiazem can prevent the usual reduction in the diameter of the coronary artery in cardiac-transplant recipients, but further follow-up will be required to determine whether diltiazem can decrease the long-term incidence of symptomatic coronary artery disease.

Adult↗