Reversible myocardial depression, manifested by ventricular dilatation and decreased ejection fraction, is common in human septic shock. A proposed mechanism, based on animal studies, is myocardial ischemia resulting from inadequate coronary blood flow. Coronary flow observations have not been reported for human septic shock. To determine whether myocardial depression in human septic shock is associated with reduced coronary flow, thermodilution coronary sinus catheters were placed in seven patients with septic shock for measurements of coronary flow and myocardial metabolism. Four of the seven patients developed myocardial depression. These patients had coronary flow similar to or higher than that of control subjects and similar to that of the other three patients, who did not develop myocardial depression. None of the patients had net myocardial lactate production. In general, compared with values in control subjects, the oxygen content difference (arterial minus coronary sinus) was narrowed, and the fractional extraction of arterial oxygen was diminished. This pattern of disordered coronary autoregulation is analogous to the pattern of arteriovenous shunting in other organs in patients with septic shock. The preservation of coronary flow, the net myocardial lactate extraction, and the increased availability of oxygen to the myocardium argue against global ischemia as the cause of myocardial depression in human septic shock. Circulation 73, No. 4, 637-644, 1986. MYOCARDIAL DEPRESSION within the first several days of human septic shock is characterized by dilatation of the left ventricle, a decrease in left ventricular ejection fraction, and maintenance of normal or increased cardiac index. 1 2 In survivors, these profound changes in ventricular function are transient and the ejection fraction generally returns to normal in 7 to 10 days.' The pathogenesis of myocardial depression in septic shock is unclear, but in canine preparations of endotoxic shock myocardial depression has been attributed to myocardial hypoperfusion caused by reduced coronary blood flow.3-7Human coronary blood flow has been studied extensively in normal subjects and in patients with coronary artery disease, by means of nitrous oxide washout, inert gas washout, and thermodilution techniques. The determinants of myocardial lactate metabolism and myocardial oxygen consumption have been characterized. Measurements dial lactate metabolism, and myocardial oxygen consumption have been reported in cardiogenict but not in septic shock in human beings. The current study was undertaken to determine whether myocardial depression in human septic shock is associated with changes in coronary blood flow and whether such changes could explain the depressed cardiac function. MethodsPatients. From October 1982 to February 1984, seven patients with septic shock were studied in the Medical Intensive Care Unit of the National Institutes of Health. The diagnosis of septic shock was based on hypotension (mean arterial pressure less than 60 mm Hg), t...
Although prednisone has been used to treat patients with idiopathic dilated cardiomyopathy, its efficacy has not been rigorously studied. We therefore randomly assigned 102 patients to either treatment with prednisone (60 mg per day) or a control group. At three months, improvement, defined prospectively as an increase in the ejection fraction of greater than or equal to 5 percentage points, was observed in 53 percent of the patients receiving prednisone and 27 percent of the controls (P = 0.005). The mean (+/- SE) ejection fraction increased 4.3 +/- 1.5 percentage points (from 17.9 +/- 1.0 to 22.2 +/- 1.6 percent) in the prednisone group, as compared with 2.1 +/- 0.8 percentage points (from 17.1 +/- 1.1 to 19.3 +/- 1.4 percent) in the control group (P = 0.054). All patients were categorized prospectively in two separately randomized subgroups. "Reactive" patients (n = 60) were those who had fibroblastic (n = 36) or lymphocytic (n = 2) infiltration or immunoglobulin deposition (n = 16) on endomyocardial biopsy, a positive gallium scan (n = 7), or an elevated erythrocyte sedimentation rate (n = 18). "Nonreactive" patients (n = 42) had none of these features. At three months, 67 percent of the reactive patients who received prednisone had improvement, as compared with 28 percent of the reactive controls (P = 0.004). Nonreactive patients did not improve significantly with prednisone (P = 0.51). After three months, reactive patients who received prednisone daily were switched to alternate-day therapy (60 mg every other day), and after six months the improvement seen earlier was no longer present. These data suggest that patients with idiopathic dilated cardiomyopathy may have some improvement when given a high dose of prednisone daily. However, the increases in the ejection fraction that we observed during prednisone treatment were small, their duration was limited, and the side effects were important. Overall, prednisone was judged to have only marginal clinical benefit, and should not be administered as standard therapy for dilated cardiomyopathy.
Eight patients with refractory ovarian cancer were treated on a pilot protocol of verapamil plus Adriamycin (Adria Laboratories, Columbus, OH). This trial was based on our previous laboratory studies which demonstrated that Adriamycin resistance in human ovarian cancer cell lines could be partially reversed by exposure of the cells to high concentrations of verapamil (3,000 ng/mL). Patients were treated in an intensive care unit with continuous cardiovascular monitoring. The dose of verapamil was escalated in each patient until hypotension or heart block developed, and this dose was maintained for 72 hours. Adriamycin (50 mg/m2) was infused over 24 hours during the second day of the verapamil infusion and verapamil alone was administered on the third day in an effort to block efflux from drug-resistant cells. This intensive approach led to a median plasma verapamil level of 1,273 ng/mL (range, 720 to 2,767). However, the high infusion rates of verapamil (9 micrograms/kg/min) required to achieve these plasma levels produced an unacceptable degree of cardiac toxicity. Two patients developed transient atropine-responsive complete heart block and four patients developed transient congestive heart failure with increases in pulmonary capillary wedge pressure. There was no evidence that the noncardiac toxicities of Adriamycin were enhanced by verapamil. There were no objective responses to therapy. Future studies should use less cardiotoxic calcium channel blockers that can be safely administered to produce the plasma levels required for in vitro sensitization of drug resistant cells.
The prevalence of myocarditis was retrospectively evaluated in 71 consecutive necropsy patients who died from acquired immunodeficiency syndrome (AIDS) between 1982 and 1986. Myocarditis was found in 37 cases (52%). Biventricular dilation at necropsy was present in seven cases (10%) and was accompanied by myocarditis in each case; fatal congestive heart failure occurred in four of these seven cases. Although viral, protozoan, bacterial, fungal and mycobacterial opportunistic pathogens were present in myocardial sections of 7 of 37 myocarditis cases, the etiology of myocarditis in the majority of these patients with AIDS remained idiopathic. Thus, myocarditis is a frequent finding at necropsy in patients with AIDS and may contribute to the development of biventricular dilation.
We observed a 48% response rate with dose-intense paclitaxel for patients with advanced-stage, platinum-resistant, recurrent ovarian cancer. The response rate is higher than previously reported for paclitaxel at a lower dose in similar cohorts of patients treated without G-CSF. Comparison of phase II studies of paclitaxel suggests a dose-response relationship. Therapy with dose-intense paclitaxel and G-CSF should be considered for patients with advanced, platinum-refractory ovarian cancer.
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