Changes in systemic sympathetic nervous system activity after mitral valve surgery and their relationship to changes in left ventricular size and systolic performance in patients with mitral regurgitation

• Published in: The American heart journal 2004-04, Vol.147 (4), p.729-735
• Main Authors: Mehta, Rajendra H, Supiano, Mark A, Grossman, P.Michael, Oral, Hakan, Montgomery, Daniel G, Briesmiester, Kerri A, Smith, Marla J, Starling, Mark R
• Format: Article
• Language: English
• Subjects: Adult; Aged; Biological and medical sciences; Cardiology; Cardiology. Vascular system; Cardiovascular disease; Endocardial and cardiac valvular diseases; Female; Heart; Heart attacks; Heart Ventricles - diagnostic imaging; Heart Ventricles - pathology; Heart Ventricles - physiopathology; Humans; Male; Medical sciences; Middle Aged; Mitral Valve - surgery; Mitral Valve Insufficiency - physiopathology; Mitral Valve Insufficiency - surgery; Norepinephrine - metabolism; Stroke Volume; Studies; Surgery; Sympathetic Nervous System - physiopathology; Systole; Ultrasonography; Ventricular Function, Left - physiology
• ISSN: 0002-8703; 1097-6744
• DOI: 10.1016/j.ahj.2003.10.020

We have shown that the systemic sympathetic nervous system (SNS) is activated in patients with chronic mitral regurgitation (MR). However, the fate of systemic SNS activity after surgical correction of MR is currently unknown. We examined 14 patients with MR who had normal sinus rhythm with an investigational, preoperative cardiac catheterization, including arterial norepinephrine (NE) sampling and [ 3H]-NE infusions and arterial blood sampling to determine NE kinetic parameters using a 2-compartment modeling analysis. The arterial NE and NE kinetic parameters were determined in all patients after mitral valve surgery (MVS) at a mean of 12 months. A 2-dimensional echocardiographic examination was also performed before and after MVS. The average extravascular NE release rates (NE 2) before and after MVS were 1.89 ± 0.66 and 2.26 ± 0.82 μg/min/m 2 ( P = .24), respectively. The average left ventricular (LV) end-diastolic dimension, fractional shortening, and ejection fraction decreased, whereas the mean LV end-systolic dimension did not change between the pre- and post-MVS echocardiographic studies. However, these group averages were comprised of patients with MR in whom the NE 2 and echocardiographic values both increased and decreased. This lack of homogeneity was a reflection of our new observation that the pre- to post-MVS changes in NE 2 were directly proportional to the changes in LV end-systolic dimension ( r = 0.91, P