The clinical presentation of patients with hourglass-like constrictions in their nerves is similar to that of patients with neuralgic amyotrophy. Histochemical analysis suggests that the pathogenesis may be immunological in origin. The role of surgery in this condition is uncertain.

Coronary heart disease is caused by atherosclerotic narrowing of coronary arteries. It accounts for about two-thirds of heart failure cases, which are frequently secondary to myocardial infarction. Despite considerable progress in the understanding and management of heart failure, its incidence, prevalence and economic burden are steadily increasing. Therefore, efficient preventive and therapeutic measures are urgently needed. In order to investigate the mechanisms involved in the pathogenesis of coronary heart disease-related heart failure and to develop therapies, appropriate animal models are indispensable. According to the aetiology of this disorder, surgical models are based on various methods allowing for the narrowing or occlusion of coronary arteries. Depending on the duration and extent of the impairment of coronary blood flow and its consequences for cardiac tissue, these are classified as models of myocardial infarction, cardiac ischemia/reperfusion injury, or chronic cardiac ischemia. In addition, factors such as species, strain, and gender of the laboratory animals also significantly contribute to the pathophysiology of the induced disorder and, therefore, have to be taken into consideration thoroughly when an animal model is to be established.

Granulocyte colony-stimulating factor (G-CSF), alone or in combination with stem cell factor (SCF), can improve hemodynamic cardiac function after myocardial infarction. Apart from impairing the pump function, myocardial infarction causes an enhanced vulnerability to ventricular arrhythmias. Therefore, we investigated the electrophysiological effects of G-CSF/SCF and the underlying cellular events in a murine infarction model.G-CSF/SCF improved cardiac output after myocardial infarction. Although G-CSF/SCF led to a twofold increased, potentially proarrhythmic homing of bone marrow (BM)-derived cells to the area of infarction, <1% of these cells adopted a cardial phenotype. Inducibility of ventricular tachycardias during programmed stimulation was reduced 5 wk after G-CSF/SCF treatment. G-CSF/SCF increased cardiomyocyte diameter, arteriogenesis, and expression of connexin43 in the border zone of the infarction. An enhanced expression of the G-CSF receptor demonstrated in cardiomyocytes and other cell types of the infarcted myocardium indicates a sensitization of the heart to direct influences of this cytokine. In addition to paracrine effects potentially caused by the increased homing of BM-derived cells, these might contribute to the therapeutic effects of G-CSF.