Sympathetic hyperactivity and aortic sympathetic nerve sprouting in patients with thoracic aortic dissection.

ABSTRACT

BACKGROUND: To determine the yet unknown relation between thoracic aortic dissection (TAD) and sympathetic nervous system activity. METHODS: Variables such as electrocardiography, blood pressure, respiratory activity, postganglionic muscle sympathetic nerve activity (MSNA), plasma norepinephrine, tyrosine hydroxylase-positive nerve fiber density, and growth-associated protein 43-positive nerve fiber density were detected and statistically analyzed. RESULTS: TAD Patients showed a significant lower R-R interval variance and higher blood pressure, heart rate, respiratory rate, MSNA, plasma norepinephrine (reflecting elevated sympathetic nervous system [SNS] activity), higher tyrosine hydroxylase, growth-associated protein 43-positive nerve fiber density (reflecting sympathetic sprouting and innervation) than those of the control group. CONCLUSIONS: In TAD patients, both overall and regional aortic SNS activities are elevated.