Isoprenaline increases Excursive Restitution Slope in the Conscious Rabbit with Ischaemic Heart Failure
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چکیده
running title: QT dynamicity in heart failure word count: 4600 TOC category: cardiovascular 2 Abstract: Background: An increased QT/RR slope is hypothesized to be predictive of sudden cardiac death after
منابع مشابه
VASODILATOR EFFECTS OF THE β -AGONIST ISOPRENALINE IN AN EXPERIMENTAL MODEL OF HEART FAILURE
Heart failure is a clinical syndrome characterized by the inability of the heart to provide nutrient supply to tissues. In 75% of cases, the underlying pathology causing heart failure in patients with cardiac death is coronary heart disease. A rabbit model of heart failure with coronary ligation was produced to mimic coronary heart disease in humans. After producing the model, two arteries ...
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Spatial heterogeneity of repolarization can provide a substrate for reentry to occur in myocardium. This heterogeneity may result from spatial differences in action potential duration (APD) restitution. The restitution portrait (RP) measures many aspects of rate-dependent restitution: the dynamic restitution curve (RC), S1-S2 RC, and short-term memory response. We used the RP to characterize ep...
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The mechanism of arrhythmogenicity in heart failure remains poorly understood. We examined the relationship between electrical abnormalities and ventricular arrhythmia by using experimental heart failure models. Sixty unipolar electrograms were recorded from the entire cardiac surface in control dogs (n = 13) and pacing-induced heart failure dogs (n = 16). In failing hearts, activation time (AT...
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BACKGROUND Apamin-sensitive K currents (I(KAS)) are upregulated in heart failure. We hypothesize that apamin can flatten action potential duration restitution (APDR) curve and can reduce ventricular fibrillation duration in failing ventricles. METHODS AND RESULTS We simultaneously mapped membrane potential and intracellular Ca (Ca(i)) in 7 rabbit hearts with pacing-induced heart failure and i...
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