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F W Smart

Publications and source records attributed to F W Smart.

12 recordsLinked to original sources
PubMed1992

Attenuation of waiting time mortality with heterotopic heart transplantation.

As the number of heart transplants and the number of transplant programs has increased, so has the waiting time for a suitable organ. To more accurately assess the magnitude of this increase and the influence of recipient size, we reviewed waiting times for large (body surface area greater than or equal to 1.95 m2) and small (body surface area less than 1.95 m2) patients with respect to era of transplantation. Patients who underwent transplantation early (1984 to December 31, 1986) waited 35 +/- 47 days (mean +/- standard deviation), whereas patients who underwent transplantation in the late era (1987 to September 30, 1989) waited 83 +/- 102 days (p = 0.001). Large patients waited longer (130 +/- 142 days) in the late era than did small patients (60 +/- 67 days; p = 0.008). During the heterotopic era (October 1, 1989 to June 30, 1990), waiting times for large patients who received a heterotopic transplant (67 +/- 46 days) were significantly shorter than those for patients who received an orthotopic transplant (166 +/- 157 days; p = 0.05). Waiting times for small patients remained unchanged. In addition, waiting time mortality decreased from 24% to 9% (p less than 0.05). Comparison of orthotopic and heterotopic procedures performed during the same era revealed no significant differences in recipient age, preoperative status, graft ischemic time, donor age, early and midterm survival, or early postoperative functional status. Heterotopic heart transplantation may effectively increase the size of the donor pool, decrease the waiting time, and decrease waiting time mortality without increasing the morbidity of the procedure.

Body Surface Area↗
PubMed1992

Current issues in advanced heart failure.

In the past 50 years, an increased understanding of the pathophysiologic mechanisms associated with the development of heart failure has produced a more precise treatment of this syndrome. The effects of the agents used for the treatment of patients with advanced heart failure have been summarized in this article and demonstrate the importance of vasodilatory drugs on the survival and progression of dilated cardiomyopathy.

Cardiomegaly↗
PubMed1991

Insensitivity of noninvasive tests to detect coronary artery vasculopathy after heart transplant.

Obstructive coronary artery vasculopathy can be a major problem after cardiac transplant. The use of noninvasive tests to detect coronary artery vasculopathy was studied in 73 consecutive patients after heart transplant. Angiographically or autopsy-proved coronary artery disease was noted in 19 consecutive patients (26%) followed prospectively for 2.5 +/- 1.3 years (mean +/- standard deviation). Patients underwent yearly surveillance echocardiographic, rest/exercise-gated wall motion, oral dipyridamole thallium, ambulatory electrocardiographic monitor and angiographic studies. Positive test results were defined by decrease in ejection fraction, wall motion abnormality, failure to increase ejection fraction, lack of systolic blood pressure increase, and ischemic ST changes at maximal exercise (or on ambulatory monitor). Wall motion abnormalities and depressed ejection fraction on echocardiography were also abnormal studies as were fixed or reversible perfusion defects on thallium scan. Angiograms were considered positive when 50% luminal narrowing was observed and autopsy coronary artery vasculopathy was defined as cross-sectional coronary obstruction greater than or equal to 70%. No procedure that was examined proved to be a sensitive noninvasive detector of heart transplant coronary artery vasculopathy. All except ambulatory electrocardiographic monitoring had positive predictive values less than 50%. Interestingly, of the techniques evaluated, echocardiography was most sensitive (53%). The poor predictive ability of noninvasive testing in this population may be due to the fact that these tests are designed to detect effects of ischemia rather than coronary obstruction alone. Use of these particular noninvasive modalities routinely after heart transplant to detect coronary artery vasculopathy should be reconsidered because of their low sensitivity and predictive value when used as a surveillance screen.

Adult↗
PubMed1991

Heterotopic heart transplantation and native heart ventricular arrhythmias.

Heterotopic heart transplantation has been said to be contraindicated in patients with serious native heart arrhythmias that produce hemodynamic instability. Placement of heterotopic allografts, however, can theoretically act as a biological biventricular assist device to provide hemodynamic support during these unstable rhythms. Further, this operation might beneficially alter the hemodynamic milieu of heart failure such that the arrhythmias are ameliorated. Described is our experience with 4 patients with heart failure receiving heterotopic cardiac allografts, documenting changes in native heart arrhythmia that occurred. These cases demonstrate that heterotopic grafts can adequately sustain hemodynamics during malignant native heart dysrhythmia. We believe native heart ventricular arrhythmias are not a contraindication to heterotopic heart transplantation.

Arrhythmias, Cardiac↗
PubMed1991

Inability of isolated soluble interleukin-2 receptor levels to predict biopsy rejection scores after heart transplantation.

Successful cardiac transplantation requires suppression of rejection, and endomyocardial biopsy is generally used to quantify this and guide immunotherapy. Biopsy, however, is an invasive, costly, cardiac catheterization with repetition limited. Since rejection requires lymphocyte activation, an alternative method of assessing rejection dynamics might be ELISA determination of soluble interleukin-2 receptor (sIL-2R) levels since induction of the interleukin-2 ligand and its receptor is required. Reports suggest that sIL-2R levels rise during kidney, liver, and heart-lung allograft rejection and heart recipients have an adverse prognosis if sIL-2R is elevated postoperatively. It is unclear, however, if serial measurements or single determinations are sufficient or if change from a baseline assessment is important. The purpose of this study was to determine if an isolated sIL-2R level after heart transplant predicted endomyocardial biopsy score at that moment. To do this, we prospectively followed 60 consecutive patients after orthotopic heart transplant and correlated 479 endomyocardial biopsy scores (McAllister scale 0-10) with matched sIL-2R levels. Regression analysis demonstrated minimal relationship between sIL-2R level and biopsy score (r =.11, r2 =.01, P=.009). When the maximum sIL-2R level for each individual patient was compared with the matched biopsy score, regression analysis revealed r=.04, r2=.001, P=.8. Likewise, when all biopsy scores and sIL-2R levels for each patient were meaned, analysis showed r=.14, r2=.02, P=.26. Thus in heart transplant patients, there is poor correlation between an isolated biopsy score and matched sIL-2R level. However, when mean +/- SEM sIL-2R was determined for severe rejection (score 7-10) and compared with sIL-2R for all other grades, it was significantly higher (1600 +/- 257 vs. 423 +/- 57 U/ml; P=.012). Still, the sensitivity, specificity, and predictive value of an sIL-2R level above 1000 U/ml predicting severe rejection was only 52%, 63%, and 8%. It would be difficult, therefore, to use a single sIL-2R determination after heart transplant to foretell the endomyocadial biopsy score. Serial measurements or quantification of a change in sIL-2R level from baseline might be more predictive of rejection severity.

Biomarkers↗
PubMed1990

Complications of flow-directed balloon-tipped catheters.

Acute or short-term complications following the use of flow-directed balloon-tipped catheters are well recognized. Long-term sequelae are rarely reported. We report herein an early complication of pulmonary arterial rupture with infarction followed by the delayed development of a pulmonary arterial aneurysm.

Aged↗
PubMed1985

Proteoglycans from lungs of rabbits treated with pronase and cadmium chloride.

The composition of proteoglycans was studied in lungs from rabbits treated intratracheally with pronase, CdCl2, or saline. Proteoglycans were extracted from the lungs by 0.5 M and 4.0 M guanidine hydrochloride (GdnHCl) in sequence. Proteoglycans were isolated from the extracts by CsCl isopycnic centrifugation and fractionated by gel filtration on a Sepharose CL-4B column. The lungs from pronase-treated rabbits had approximately 33% greater total uronate than did lungs from saline-treated control animals, whereas CdCl2-treated rabbit lungs had 28% less uronate than did control lungs. Pronase-treated animal lungs had a greater proportion of hyaluronic acid and dermatan sulfate than did the control animal lungs. Relatively greater amounts of uronate were extracted by 0.5 M GdnHCl from the enzyme-treated rabbit lungs than from the CdCl2- or saline-treated animal lungs. The concentrations of hyaluronic acid and heparan sulfate in 0.5 M GdnHCl extract and dermatan sulfate in 4.0 M GdnHCl extract were greater in pronase-treated animal lungs than in control lungs. Gel filtration of proteoglycans sedimented at q greater than 1.45 revealed that pronase-treated animal lungs had proteoglycans smaller in molecular size than those in control lungs. The observations indicate that intratracheal treatment with pronase and CdCl2 alters the composition of proteoglycans in the lung, and such alterations are likely important in the pathogenesis of emphysema.

Animals↗
PubMedDate not supplied

Sudden death caused by bradycardia and asystole in a heart transplant patient with coronary arteriopathy.

The mechanism of death as a result of allograft ischemic heart disease is not well characterized. Ventricular tachycardia and fibrillation may not be the terminal events they often are in the general population. We report observations in a 41-year-old man with cardiac allograft arteriopathy who died suddenly while wearing an ambulatory monitor. The lethal rhythm was a progressive bradycardia terminating in asystole. Autopsy revealed epicardial and small vessel intramyocardial, coronary arteriopathy, and only mild allograft rejection. It is our belief that ischemia caused the bradycardic sudden death. We would like to hypothesize that prophylactic permanent pacemaker implantation may prevent bradycardic sudden death and improve survival in heart transplant patients with coronary disease.

Adult↗
PubMedDate not supplied

Elevated soluble interleukin-2 receptor levels early after heart transplantation and long-term survival and development of coronary arteriopathy.

Rejection dynamics after heart transplantation might be characterized by soluble interleukin-2 receptor levels. To determine whether elevated levels early (measured by enzyme-linked immunosorbent assay once weekly the first 3 weeks at time of heart biopsy) after transplantation predict mortality and development of coronary disease, the means of these three determinations and the endomyocardial biopsy scores (McAllister scale 0-10) were compared for survivors and nonsurvivors and patients who had coronary arteriopathy develop and those who did not. Fifty-five patients alive 30 days after heart transplantation were prospectively followed up. Overall, 47 patients were male (85%), and the median age was 51 years. Mean +/- SD follow-up was 26 +/- 15 months (range, 1 to 54 months). There were 38 survivors (69%), and coronary arteriopathy developed in 15 patients (27%). Whereas mean +/- SD heart biopsy scores for the early weeks were similar between survivors and nonsurvivors (3.6 +/- 1.4 vs 4.4 +/- 1.6; p greater than 0.05), the difference in soluble interleukin-2 receptor levels was significant (703 +/- 362 U/ml vs 1793 +/- 1070 U/ml; p less than 0.001). A mean level less than 1000 U/ml in any given patient predicted long-term survival with a 76% sensitivity, 79% specificity, and 88% negative predictive value. Mean receptor levels for those patients in whom coronary arteriopathy did not develop were 880 +/- 846 U/ml and for those with this difficulty, 1410 +/- 590 U/ml (p = 0.001). Late morbidity and mortality after heart transplantation seem predicted by early elevation of plasma soluble interleukin-2 receptor levels.(ABSTRACT TRUNCATED AT 250 WORDS)

Biopsy↗