R N Sampsell

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The susceptibility to the toxic arrhythmogenic effects of digitalis was studied in to normal dogs (group 1) and in 15 dogs with healed myocardial infarction (group 2) 26 ± 5 days after coronary artery ligation. The dose of ouabain required to cause stable digitalis-toxic ventricular tachycardia was 25% less in the group 2 dogs than in the group 1 control(More)
An asymmetric biphasic pulse which stimulates the heart and neutralizes the poststimulation polarization at the electrode-myocardial interface permitting the recording of the evoked endocardial response (EER) up to approximately 1 ms poststimulation with the same electrode used for stimulation is described. Using this mode of cardiac stimulation in 20 dogs(More)
Local ventricular activation time and the conduction time during sinus rhythm at the induction of ventricular tachycardia (VT) and ventricular fibrillation (VF) were investigated using a canine model of chronic myocardial infarction. Of 26 dogs studied, 15 had inducible VT, 10 had inducible VF, and 1 had no inducible arrhythmias. Bipolar local ventricular(More)
In vivo leukocyte adherence has many physiological implications but the effect of vessel size and hemodynamic parameters on adherence initiation remains unclarified. The early phases of adherence, defined to include attachment of previously freely moving leukocytes to endothelium or leukocytes which roll along the vessel wall, are the focus of this report.(More)
BACKGROUND We studied arrhythmogenesis and its underlying pathophysiology during graded reductions of coronary blood flow, superimposed on prior myocardial infarction to test the hypothesis that spontaneous ventricular fibrillation and induced ventricular tachycardia are dependent on different patterns of coronary flow reduction in hearts with prior(More)
Fish intake has long been recognized to play an important role in human health, for example, in reduction of the incidence of heart disease and some cancers and as immunosuppressors. In this study, we examined the effect of dietary supplementation with fish oils (FO) on monocytic procoagulant activity (PCA) in dogs. Six mongrel dogs were fed daily chow(More)
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