Stay Connected. Manage Your Care.
Access your health information anytime and anywhere, at home or on the go, with MyHealth.
- Message your clinic
- View your lab results
- Schedule your next appointment
- Pay your bill
The MyHealth mobile app from Stanford Health Care puts all your health information at your fingertips and makes managing your health care simple and quick.
Guest Services
24/7
We are available to assist you
whenever you need it. Give us a call at
650-498-3333 or
PHYSICIAN HELPLINE
Have a question? We're here to help! Call 1-866-742-4811
Monday - Friday, 8 a.m. - 5 p.m.
REFER A PATIENT
Fax 650-320-9443
Track your patients' progress and communicate with Stanford providers conveniently and securely.
Abstract
The functional significance of the autonomic nerves in the anterior mitral valve leaflet (AML) is unknown. We tested the hypothesis that remote stimulation of the vagus nerve (VNS) reduces AML stiffness in the beating heart.Forty-eight radiopaque-markers were implanted into eleven ovine hearts to delineate left ventricular and mitral anatomy, including an AML array. The anesthetized animals were then taken to the catheterization laboratory and 4-D marker coordinates obtained from biplane videofluoroscopy before and after VNS. Circumferential (E(circ)) and radial (E(rad)) stiffness values for three separate AML regions, Annulus, Belly and Edge, were obtained from inverse finite element analysis of AML displacements in response to trans-leaflet pressure changes during isovolumic contraction (IVC) and isovolumic relaxation (IVR).VNS reduced heart rate: 94±9 vs. 82±10min(-1), (mean±SD, p<0.001). Circumferential AML stiffness was significantly reduced in all three regions during IVC and IVR (all p<0.05). Radial AML stiffness was reduced from control in the annular and belly regions at both IVC and IVR (P<0.05), while the reduction did not reach significance at the AML edge.These observations suggest that one potential functional role for the parasympathetic nerves in the AML is to alter leaflet stiffness. Neural control of the contractile tissue in the AML could be part of a central control system capable of altering valve stiffness to adapt to changing hemodynamic demands.
View details for DOI 10.1016/j.jbiomech.2012.04.009
View details for Web of Science ID 000307318300023
View details for PubMedID 22703898