ABSTRACT
Technical developments have enabled
direct methods to be used for SNS assessment
such as microneurography8 (direct intraneural
recordings of, for example, peroneal
sympathetic nerve traffic). Microneurography
has confirmed that SNS activity correlates
with cardiac index, stroke volume index, and
systemic and pulmonary vascular resistances,
Modern indirect methods of SNS assessment
collectively confirm that SNS activity is
progressively increased, and parasympathetic
activity blunted,12,13 as left ventricular
dysfunction develops into clinical chronic
heart failure and the syndrome increases in
severity. Although SNS activity is related to
severity of heart failure, an irrefutable
demonstration that increased SNS output
directly causes or contributes to the decline in
cardiac performance and disease progression
remains elusive.
