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R C Starling

Publications and source records attributed to R C Starling.

78 records · Page 5Linked to original sources
PubMedDate not supplied

Thermodilution measures of right ventricular ejection fraction and volumes in heart transplant recipients: a comparison with radionuclide angiography.

A reliable, convenient measure of right ventricular ejection fraction may be a useful adjunct to evaluate cardiac allograft rejection. The purpose of this investigation was to compare two measures of right ventricular ejection fraction: (1) radionuclide angiography with the first-pass technique and (2) thermodilution with a balloon flotation catheter. The study was performed in 26 heart transplant recipients; hemodynamics, thermodilution cardiac output, and right ventricular ejection fraction were measured. First pass radionuclide angiography was performed either simultaneously (n = 11) or within 4 hours (n = 15) of the thermodilution study. Mean thermodilution right ventricular ejection fraction was 39% +/- 8%, and radionuclide angiography ejection fraction was 47% +/- 9%, which represents a highly significant difference (p < 0.001) in techniques. Linear regression showed no correlation between the two techniques (r = 0.3; p = NS). No differences in results were observed in those studied simultaneously versus less than 4 hours. We conclude that the thermodilution technique underestimates right ventricular ejection fraction in heart transplant recipients and that its usefulness as a tool to screen for systolic dysfunction related to rejection is limited.

Cardiac Catheterization↗
PubMedDate not supplied

Adenine nucleotide content in cold preserved human donor hearts and subsequent cardiac performance after orthotopic heart transplantation.

Myocardial high-energy phosphate content has been used as a parameter to evaluate the adequacy of donor organ preservation. The purpose of this study was to assess current techniques of preservation by measuring high-energy phosphates in cold preserved (4 degrees C) human donor hearts. Endomyocardial biopsy samples of the donor heart right ventricular septum (n = 24) were compared with samples from patients with normal cardiac function evaluated before chemotherapy (n = 12). Left ventricular and right ventricular ejection fractions were measured by means of radionuclide angiography early (24 to 72 hours) and late (mean 42 days) postoperatively. Mean total cold ischemic time was 146 +/- 54 minutes (range, 89 to 340 minutes). ATP nmol/mg noncollagenous protein in donor hearts was 38.2 +/- 10.7 and 31.9 +/- 13.6 (p = NS) in normal hearts. Early postoperative left ventricular and right ventricular ejection fraction was 55% +/- 14% and 40% +/- 9%, respectively. Late postoperative left ventricular and right ventricular ejection fraction was 64% +/- 14% and 50% +/- 10%, respectively; both represent significant increases in right and left ventricular ejection fraction (p less than 0.05). No correlation was found between ischemic time and donor ATP, ischemic time and ejection fraction, or ejection fraction and ATP. Three patients with normal donor heart ATP content had severe, but reversible, early graft dysfunction. In summary, currently used human donor heart preservation techniques are associated with normal values of high-energy phosphates and usually excellent early and late postoperative graft function.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenine Nucleotides↗
PubMedDate not supplied

Permanent pacing in heart transplant recipients: underlying causes and long-term results.

Although the majority of heart transplant recipients have a satisfactory heart rate, a substantial number require a permanent pacemaker. In 7 of 46 heart transplant patients at our institution symptomatic bradycardia developed, necessitating implantation of a transvenous pacemaker. The average time from heart transplantation to pacer insertion was 25 days. The average donor age, ischemic period, and crossclamp time was 28 years, 182 minutes, and 113 minutes, respectively. A long aortic crossclamp time (greater than 83 minutes) increased the risk for conduction abnormalities in the sinoatrial node. No patient had rejection before the pacer implantation. Five of the seven patients continue to be paced a significant amount of a 24-hour period. Only one patient has had considerable improvement in 3 years, requiring pacing only 3% of a monitored 24-hour period. This patient had the longest ischemic time and the most rejection episodes after implantation of the pacemaker. One patient was paced 100% until a second heart transplantation was done, without a subsequent need for pacing. The other five patients' hearts continue to be paced between 80% and 100% of a 24-hour monitored period. The donor intrinsic heart rates of these five patients produce symptomatic bradycardia. The success of AAI pacing in all patients indicates normal conduction below the sinoatrial node. The injury or dysfunction resulting in bradycardia was isolated to the sinoatrial node. Long-term follow-up in three patients (greater than 3 years) shows the need for pacing to be intermittent but long term. Most patients never fully recover from symptomatic bradycardia.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMedDate not supplied

Results of heart transplantation for active lymphocytic myocarditis.

To determine whether the heart-specific immunoreactivity associated with active myocarditis affects outcome after heart transplantation, we retrospectively analyzed the outcome of 12 patients with active lymphocytic myocarditis in their explanted native hearts identified by the Registry of the International Society for Heart Transplantation. The patients were 38 +/- 10 years of age and predominantly female (75%). In nine patients (75%), endomyocardial biopsy showed active myocarditis before transplant; eight of these patients also received immunosuppression before transplant. Recipient hemodynamic study before transplantation demonstrated an ejection fraction of 0.18 +/- 0.06, cardiac index of 1.7 +/- 0.4 L/min/m2, pulmonary artery pressure of 41 +/- 6/23 +/- 6 mm Hg, and mean pulmonary capillary wedge pressure of 30 +/- 5 mm Hg. Left ventricular end-diastolic dimension by echocardiography was 6.0 +/- 1.4 cm. Four of the patients were dependent on intravenous inotropes, and six required mechanical assistance. Over a 36-month follow-up period, 2.9 +/- 2.4 episodes of rejection occurred per patient. Sixty percent of the first episodes occurred within 2 weeks of transplantation. These patients experienced a 2.2 +/- 1.1-fold increase in rejection compared with institutional average rejection rates. Survival was significantly shorter than that of age-matched or female control subjects. This study is limited by its retrospective nature and the unusual pretransplant characteristics of the subjects. It indicates that active myocarditis may predispose patients to early severe rejection and a high mortality rate after heart transplantation.

Adult↗
PubMedDate not supplied

Influence of HLA mismatch on rejection after heart transplantation: a multiinstitutional study. The Cardiac Transplant Research Database Group.

HLA mismatch has been shown to influence survival after heart transplantation. No large multicenter study has examined the effect of HLA mismatch on cardiac allograft rejection. HLA mismatch and other potential risk factors for rejection were analyzed in data from 27 institutions (1719 patients) participating in the Cardiac Transplant Research Database between January 1, 1990, and June 30, 1992. Complete HLA information on the A, B, and DR loci was available for both donor and recipient in 1190 patients. Of these, 619 (52%) had five or six mismatches; 68 (6%) had zero, one, or two mismatches. The mean number of mismatches was 4.4 and did not differ, regardless of donor-recipient race match (4.3 versus 4.8, p = 0.19). According to multivariate analysis, risk factors for time to first rejection included younger recipient age (p < 0.0001), female gender of both donor and recipient (p < 0.0006), number of HLA mismatches (p = 0.013) and black recipient race (p < 0.004). Patients with zero, one, or two mismatches (n = 67) had a 54% freedom from rejection at 1 year versus 36% for patients with three or more mismatches (n = 1005, p = 0.02). HLA mismatch number did not affect time to first rejection or rejection frequency among black patients. Risk factors (by multivariate analysis) for death or retransplantation because of rejection included female recipient gender (p = 0.008) and black recipient race (p = 0.006). The probability of rejection-related death or retransplantation by 2 years was 0% with zero, one, or two HLA mismatches versus 5% for three to six mismatches (p = 0.14). These findings should stimulate further investigation of methods to clarify the HLA effect in heart transplantation and eventually the use of HLA typing in donor-recipient selection.

Actuarial Analysis↗