title: Sympathetic neural responses to coronary occlusion during balloon angioplasty.
abstract: OBJECTIVE
  The sympathetic nervous system is a key modulator of prognosis and outcome in cardiac ischaemia and infarction. The effects of acute cardiac ischaemia on sympathetic neural traffic in humans are unknown. We tested the hypothesis that angioplasty, and associated transient myocardial ischaemia, elicits changes in neural circulatory control, including direct intraneural measures of sympathetic traffic.
  
  
  METHODS
  We measured muscle sympathetic nerve activity (MSNA), blood pressure and heart rate in 12 patients (11 men, one woman) undergoing clinically indicated elective coronary angioplasty of the left anterior descending (n = 7) or circumflex (n = 5) coronary artery. Baseline data were obtained for 2 min before occlusion. Each balloon inflation was designed to last up to 120 s.
  
  
  RESULTS
  Coronary occlusion had no significant effect on blood pressure or heart rate. In contrast, occlusion resulted in a significant increase in MSNA, in 10 of the 12 patients, and in all seven of those patients undergoing angioplasty of the left anterior descending artery. The group mean increase in MSNA during occlusion was 36 +/- 11% (P = 0.008 versus preocclusion). MSNA increased within 60 s of occlusion (129 +/- 12% of baseline; n = 12; P = 0.04), and increased further during the next 60 s to 141 +/- 12% of baseline levels (n = 10; P < 0.001). Increases in MSNA were similar in patients with and without significant chest pain (39 +/- 9% versus 34 +/- 13%, respectively; P = 0.84).
  
  
  CONCLUSIONS
  Acute coronary occlusion during angioplasty increases central sympathetic outflow, but there is no systematic change in heart rate. The increase in sympathetic nerve traffic cannot be explained by blood pressure changes or occlusion-related chest pain.
authors.affiliation: Institute of Cardiology, Medical University of Gdańsk, Gdańsk, Poland.
authors.forename: Dariusz
authors.initials: D
authors.lastname: Ciećwierz
authors.forename: Dagmara
authors.initials: D
authors.lastname: Hering
authors.forename: Virend K
authors.initials: VK
authors.lastname: Somers
authors.forename: Joanna
authors.initials: J
authors.lastname: Wdowczyk-Szulc
authors.forename: Tomas
authors.initials: T
authors.lastname: Kara
authors.forename: Paweł
authors.initials: P
authors.lastname: Skarzyński
authors.forename: Andrzej
authors.initials: A
authors.lastname: Rynkiewicz
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Narkiewicz
mesh_terms: D000800:Angioplasty, Balloon; D003327:Coronary Disease / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D013564:Sympathetic Nervous System / Q000503:physiopathology*