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Myocardial preservation during open heart surgery is a subject of intense investigation. A prerequisite for further improvement is a better understanding of the underlying pathophysiologic mechanisms responsible for postoperative myocardial stunning. In this report, we analyzed the role of apoptosis in myocardial stunning.Myocardial samples were obtained from 11 patients undergoing elective coronary artery bypass grafting before (control) and after cardioplegic arrest and reperfusion. Specimens were examined for apoptosis by electron microscopy, in situ end-labeling of DNA fragments, and biochemically for mitochondrial cytochrome c release.Electron microscopy revealed condensation and margination of nuclear chromatin after surgery, as well as swelling and membrane rupture in mitochondria of single myocytes surrounded by healthy cells. TUNEL-positive cells were also found. Cytochrome c release, an initial step in apoptosis, revealed a 3.4 +/- 0.4-fold increase during surgery (p0.0001). Furthermore, cytochrome c release from otherwise intact mitochondria showed a negative correlation with left ventricular function and a positive correlation with the duration of cardioplegic arrest and reperfusion (p0.05).Our data demonstrate that programmed cell death is evident early after open heart surgery and correlates with declining cardiac contractility. We conclude that apoptosis may be an important mechanism in postoperative myocardial stunning.

Tumors of the inferior vena cava are rarely complicated by pulmonary tumor embolism. We report a patient with a leiomyosarcoma of the inferior vena cava complicated by an embolus in the left pulmonary artery. We describe the successful treatment of this condition, which consisted of cavoplasty and pulmonary endarterectomy conducted under hypothermic circulatory arrest. Different aspects of the surgical strategy are discussed.

Somatostatin receptor scintigraphy with 111In-[DTPA-D-Phe1]-octreotide has the potential for visualizing primary and recurrent thymomas in patients with myasthenia gravis, whereas thymic hyperplasias fail to accumulate somatostatin analog peptides. We demonstrate somatostatin receptor imaging findings in a patient with a mixed encapsulated thymoma which exhibited intense 111In-[DTPA-D-Phe1]-octreotide uptake in early and late scans. In another patient with a history of malignant thymoma 111In-[DTPA-D-Phe1]-octreotide accumulation was clearly seen in a mass suspected to be a recurrence. This paper describes the imaging protocol including Single Photon Emission Computed Tomography (SPECT) and discusses the clinical applications of this feasible functional imaging method in patients with thymomas.

Tuberbculous aneurysms of the aorta are supposed to be exceedingly uncommon. In a recent review of the English literature from 1945 to 1999, 41 cases were counted, with only 2 aneurysms located at the aortic arch.1 Incidence and presentation of tuberculosis change rapidly because of migration, traveling, and immunosuppression. Multiresistant strains and comorbidity impair the effects of medical therapy and might result in surgical complications.2 Here we report on 2 patients on whom we have operated for tuberculous pseudoaneurysms of the aortic arch.