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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, RESULTS. Meshes: Atrial Fibrillation, Blood Pressure, Chronic Disease, Female, Heart Failure, Hemodynamics, Humans, Male, Middle Aged, Norepinephrine, Sympathetic Nervous System.
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Does chronic atrial fibrillation influence the magnitude of sympathetic overactivity in patients with heart failure? Context: In this study we sought to assess the influence of atrial fibrillation (AF) on sympathetic nervous system overactivity in congestive heart failure (CHF) patients. We studied 133 consecutive patients with moderate to severe CHF. Subjects underwent haemodynamic assessment (right heart catheterization) and assessment of total systemic and cardiac sympathetic activity by the norepinephrine (NE) spillover method. The study population included 108 patients in sinus rhythm (SR) and 25 in AF. While AF patients had a lower cardiac output (CO) (SR vs AF: 4.2+/-0.1 vs 3.7+/-0.2l/min, P<0.05), the groups were otherwise matched for systemic blood pressure (BP), heart rate and filling pressures. In conjunction, total body NE spillover (SR vs AF: 5.8+/-0.4 vs 4.9+/-0.5 nmol/min, P>0.05) and cardiac NE spillover (SR vs AF: 339+/-21 vs 393+/-49 pmol/min, P>0.05) were not significantly different between the two groups, while the systemic clearance rate for NE was lower in the AF group (SR vs AF: 2.2+/-0.1 vs 1.6+/-0.1l/min, P<0.05).
assistant
Congestive heart failure patients in AF do not appear to have heightened sympathetic tone compared to CHF patients in SR. Final Decision: no