Margaret E. Billingham

A Clinical Trial of Immunosuppressive Therapy for Myocarditis

BACKGROUND Myocarditis is a serious disorder, and treatment options are limited. This trial was designed to determine whether immunosuppressive therapy improves left ventricular function in patients with myocarditis and to examine measures of the immune response as predictors of the severity and outcome of disease. METHODS We randomly assigned 111 patients with a histopathological diagnosis of myocarditis and a left ventricular ejection fraction of less than 0.45 to receive conventional therapy alone or combined with a 24-week regimen of immunosuppressive therapy. Immunosuppressive therapy consisted of prednisone with either cyclosporine or azathioprine. The primary outcome measure was a change in the left ventricular ejection fraction at 28 weeks. RESULTS In the group as a whole, the mean (+/- SE) left ventricular ejection fraction improved from 0.25 +/- 0.01 at base line to 0.34 +/- 0.02 at 28 weeks (P < 0.001). The mean change in the left ventricular ejection fraction at 28 weeks did not differ significantly between the group of patients who received immunosuppressive therapy (a gain of 0.10; 95 percent confidence interval, 0.07 to 0.12) and the control group (a gain of 0.07; 95 percent confidence interval, 0.03 to 0.12). A higher left ventricular ejection fraction at base line, less intensive conventional drug therapy at base line, and a shorter duration of disease, but not the treatment assignment, were positive independent predictors of the left ventricular ejection fraction at week 28. There was no significant difference in survival between the two groups (P = 0.96). The mortality rate for the entire group was 20 percent at 1 year and 56 percent at 4.3 years. Features suggesting an effective inflammatory response were associated with less severe initial disease. CONCLUSIONS Our results do not support routine treatment of myocarditis with immunosuppressive drugs. Ventricular function improved regardless of whether patients received immunosuppressive therapy, but long-term mortality was high. Patients with a vigorous inflammatory response had less severe disease.

Antiatherogenic effects of L-arginine in the hypercholesterolemic rabbit.

The purpose of this study was to determine if chronic administration of L-arginine, the precursor of endothelium-derived relaxing factor (EDRF), normalizes endothelium-dependent relaxation and decreases atherosclerosis in hypercholesterolemic animals. Male rabbits were fed (a) normal rabbit chow; (b) 1% cholesterol diet; or (c) 1% cholesterol diet supplemented by 2.25% L-arginine HCl in drinking water. Arginine supplementation doubled plasma arginine levels without affecting serum cholesterol values. After 10 wk, the thoracic aorta was harvested for studies of vascular reactivity and histomorphometry. Endothelium-dependent relaxations (to acetylcholine and calcium ionophore A23187) were significantly impaired in thoracic aortae from animals fed a 1% cholesterol diet. By contrast, vessels from hypercholesterolemic animals receiving L-arginine supplementation exhibited significantly improved endothelium-dependent relaxations. Responses to norepinephrine or nitroglycerin were not affected by either dietary intervention. Histomorphometric analysis revealed a reduction in lesion surface area and intimal thickness in thoracic aortae from arginine-supplemented animals compared to those from untreated hypercholesterolemic rabbits. This is the first study to demonstrate that supplementation of dietary L-arginine, the EDRF precursor, improves endothelium-dependent vasorelaxation. More importantly, we have shown that this improvement in EDRF activity is associated with a reduction in atherogenesis.

Heart-lung transplantation: successful therapy for patients with pulmonary vascular disease.

: We report our initial experience with three patients who received heart-lung transplants. The primary immunosuppressive agent used was cyclosporin A, although conventional drugs were also administered. In the first patient, a 45-year-old woman with primary pulmonary hypertension, acute rejection of the transplant was diagnosed 10 and 25 days after surgery but was treated successfully; this patient still had normal exercise tolerance 10 months late. The second patient, a 30-year-old man, underwent transplantation for Eisenmengers syndrome due to atrial and ventricular septal defects. His graft was not rejected, and his condition was markedly improved eight months after surgery. The third patient, a 29-year-old woman with transposition of the great vessels and associated defects, died four days postoperatively of renal, hepatic, and pulmonary complications. We attribute our success to experience with heart-lung transplantation in primates, to the use of cyclosporin A, and to the anatomic and physiologic advantages of combined heart-lung replacement. We hope that such transplants may ultimately provide an improved outlook for selected terminally ill patients with pulmonary vascular disease and certain other intractable cardiopulmonary disorders.

Doxorubicin Cardiomyopathy: Evaluation by Phonocardiography, Endomyocardial Biopsy, and Cardiac Catheterization

Right ventricular endomyocardial biopsy, right heart catheterization, and systolic time intervals were done in 33 adult patients receiving doxorubicin (AdriamycinTM). Doxorubicin administration was associated with a dose-related increase in the degree of myocyte damage, and 27 of 29 patients biopsied at doses greater than or equal to 240 mg/m2 had doxorubicin-associated degenerative changes identified on biopsy. The pre-ejection period to left ventriculr ejection time ratio (PEP/LVET) showed a threshold phenomenon and did not begin to increase until a total dose of 400 mg/m2 had been reached. Seven patients with catheterization-proven heart failure had a significantly greater amount of myocyte damage on biopsy than dose-matched control subjects (P less than 0.01). Preveious mediastinal radiation appeared to potentiate the doxorubicin-associated degenerative process. Mediastinal radiation and age greater than or equal to 70 years appeared to be risk factors for doxorubicin-associated heart failure. Dose limitation by combined clinical, noninvasive, invasive, and morphologic criteria offered an advantage over empirical dose limitation or dose limitation by PEP/LVET alone.

Early Anthracycline Cardiotoxicity

Eight patients in whom cardiac dysfunction developed within four weeks of receiving their first or second course of daunorubicin or doxorubicin are described. Four patients presented with pericarditis; three of these four had evidence of myocardial dysfunction. Histopathologic analysis of these patients was consistent with an acute myocyte damage and secondary inflammatory process. An additional group of four patients presented with symptoms and signs of heart failure. These patients were either elderly or had evidence of previous cardiac disease. One of these patients suffered a myocardial infarction 24 hours after receiving 60 mg/m2 of daunorubicin; earlier doses in the same course had been associated with evidence of myocardial ischemia. We conclude that anthracycline antibiotics may manifest clinically significant cardiotoxicity at total cumulative doses much less than have been associated with chronic cardiomyopathy.

Structural changes in glutaraldehyde-treated porcine heterografts used as substitute cardiac valves: Transmission and scanning electron microscopic observations in 12 patients

Scanning and transmission electron microscopic studies were made of (1) 12 glutaraldehyde-treated porcine valvular heterografts that had been implanted in patients for 2 days to 76 months; (2) 3 unimplanted commercially processed porcine aortic valves; and (3) 1 unprocessed porcine aortic valve. Comparison of unprocessed porcine valves and unimplanted commercially processed valves showed loss of endothelium and acid mucopolysaccharides during preimplantation processing. Short-term (less than 2 months) changes after implantation consisted of insudation of plasma proteins, penetration of erythrocytes into surface crevices, formation of a thin surface layer of fibrin, and deposition of macrophages, giant cells and a few platelets. Longer-term (more than 2 months) changes were proportional to the time interval after implantation and consisted of progressive disruption of collagen, erosion of the valve surfaces, formation of aggregates of platelets and accumulation of lipid. The surfaces of the leaflets did not become covered with endothelium or with a fibrous sheath. Calcific deposits were found in one valve and bacterial organisms in another. Thus, progressive breakdown of collagen appears to be a critical factor in determining the long-term durability of glutaraldehyde-treated porcine valvular heterografts.

Treatment of acute inflammatory myocarditis assisted by endomyocardial biopsy

Abstract Right ventricular endomyocardial biopsy was performed to make a diagnosis of inflammatory myocarditis in 10 patients with congestive heart failure. All 10 patients were treated with immunosuppressive agents (either prednisone alone or prednisone in combination with azathioprine) and were followed up prospectively. Each patient had serial invasive and noninvasive assessments of cardiac performance, and 9 of 10 had one or more follow-up endomyocardial biopsies. The course of four patients who showed dramatic improvement in association with immunosuppressive therapy is described in detail. In addition to these four patients, one other had definite improvement and four subjects had stabilization of previously progressive heart failure; the condition of one patient worsened, and he died despite immunosuppression. In the seven patients who had cell inflammation, six underwent a second biopsy after a period of immunosuppressive therapy, and in each case, the inflammatory infiltrate had been eliminated. In two of these patients, signs and symptoms of myocarditis recurred after discontinuation of therapy, and myocardial biopsy confirmed the recrudescence of cell inflammation. Reinstitution of therapy improved symptoms and histologic findings. It is concluded that endomyocardial biopsy can be used to diagnose inflammatory myocarditis and to monitor the histologic results of therapy. Our findings constitute circumstantial evidence that immunosuppressive therapy is effective in eliminating myocardial cell inflammation and thereby improving myocardial performance.

Transplant coronary artery disease: Histopathologic correlations with angiographic morphology

Accelerated coronary artery disease is a major cause of morbidity and mortality among cardiac transplant recipients. Ten patients who died or underwent retransplantation within 2 months of coronary angiography had direct correlation of angiographic (normal discrete lesions, diffuse concentric narrowing) with histologic appearance of coronary arteries. Of the 26 angiographically normal segments, 73% showed mild to moderate fibrous intimal thickening by light microscopy. The remainder had intermediate lesions or atheromatous plaques. Discrete stenoses usually corresponded to lipid-rich intermediate or atheromatous disease. In contrast, angiographically diffuse, concentrically narrowed lesions usually were areas of severe fibrous intimal thickening. Fresh or organizing thrombus was most often associated with discrete lesions and accounted for all complete occlusions. Histologic and angiographic comparisons of the degree of luminal narrowing showed generally good correlation for high grade stenoses. Lesions graded as having less than 25% diameter narrowing were often underestimated angiographically as compared with histologic determinations. Transplant coronary artery disease has a heterogeneous histologic and angiographic appearance, with angiographic underestimation of disease in some patients.

Treatment with rapamycin and mycophenolic acid reduces arterial intimal thickening produced by mechanical injury and allows endothelial replacement

Rapamycin (RPM) and mycophenolic acid (MPA) inhibit immune responses by antagonizing IL-stimulated lymphocyte activation. These 2 drugs, used alone or preferably in combination, also significantly reduced the response of vascular cells to balloon-catheter arterial injury in rats. When rats were treated for 2 weeks with both drugs starting the day of injury, intimal thickening was significantly reduced (P < 0.001) 14 days after injury; however, by 44 days after injury, intimal thickening had progressed to the extent measured in arteries of untreated control rats. When RPM and MPA were administered for 3 days before and 13 days after injury, arterial intimal thickening was significantly (P = 0.024) reduced and endothelium had regrown in vessels analyzed 44 days after injury. Compared with initiation of treatment on the day of injury, starting the administration of RPM plus MPA before injury appears to limit the activation of cells or actions of factors responsible for the progression of intimal thickening that occurred after the administration of the drugs was terminated. RPM and MPA prevented the development of arterial intimal thickening in a model not dependent upon a rejection response. This direct antiproliferative action on smooth muscle cells by RPM and MPA, in vivo, may prevent the development of arterial intimal thickening associated with chronic rejection.

The use of cardiac biopsy to demonstrate reduced cardiotoxicity in AIDS Kaposi's sarcoma patients treated with pegylated liposomal doxorubicin

BACKGROUND Pegylated liposomal doxorubicin (PL-DOX) has been shown in preclinical models to induce less cardiotoxicity than non-liposomal doxorubicin. Endomyocardial biopsy is a highly sensitive and specific method for detecting anthracycline-induced cardiac damage. PATIENTS AND METHODS Myocardial tissue from ten KS patients who had received cumulative PL-DOX (20 mg/m2/biweekly) of 440-840 mg/m2 was evaluated for evidence of anthracycline-induced cardiac damage. Controls were assembled from patients who had received cumulative doxorubicin doses of 174-671 mg/m2 in two earlier cardiac biopsy protocols. Two control groups were selected on the basis of both cumulative (+/- 10 mg/m2) and peak doxorubicin dose (60 or 20 mg/m2, control group 1), or peak dose alone (20 mg/m2, control group 2). RESULTS PL-DOX patients had significantly lower biopsy scores compared with those of doxorubicin controls despite higher cumulative doses of anthracycline. The median biopsy scores for the PL-DOX and doxorubicin groups, respectively, were 0.3 vs. 3.0 (P = 0.002, Cochran-Mantel-Haenszel row mean difference test) for group 1 and 1.25 for group 2 (P < 0.001, Wilcoxon rank-sum test). CONCLUSIONS Less severe cardiac changes were seen in patients given PL-DOX relative to historical control patients given comparable cumulative doses of doxorubicin.