Gender differences in sympathetic neural activation following uncomplicated acute myocardial infarction.
OBJECTIVE
To determine whether the magnitude of post-acute myocardial infarction (AMI) sympathetic activation is greater in women (F-AMI) than men (M-AMI).


RESULTS
Both sympatho-humoral activation and female gender are associated with worse outcome in the early phase following AMI. However, women have lower sympathetic output than men. We therefore examined matched groups of F-AMI (18) and M-AMI (18) patients 2-4 days following uncomplicated AMI, then 3 monthly to 9 months; matched normal control (NC) groups comprised M-NC (18) and F-NC (18). Muscle sympathetic nerve activity (MSNA) was measured by microneurography. Muscle sympathetic nerve activity was lower in the F-NC than M-NC (at least P < 0.05) and greater in the two AMI groups than their corresponding NC groups (at least P < 0.001). Muscle sympathetic nerve activity was similar in the F-AMI and M-AMI groups indicating a post-AMI increase in women of about twice that in men (P < 0.0001). Both AMI groups returned to corresponding NC (lower in women) levels by 9 months.


CONCLUSIONS
Following uncomplicated AMI, women developed a relatively greater magnitude of sympathetic activation lasting until its resolution at 9 months. This is consistent with reports of their worse prognosis observed during this time period, with important potential clinical implications.
Hogarth
Andrew J
AJ
Department of Cardiology, Leeds Teaching Hospital NHS Trust, G floor, Jubilee wing, Leeds General Infirmary, Great George Street, Leeds LS1 3EX, UK. andy_hogarth2003@yahoo.co.uk
Graham
Lee N
LN
Mary
David A S G
DA
Greenwood
John P
JP
D000200:Action Potentials / Q000502:physiology*; D000208:Acute Disease; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000503:physiopathology*; D009431:Neural Conduction / Q000502:physiology*; D011379:Prognosis; D011446:Prospective Studies; D012737:Sex Factors; D013564:Sympathetic Nervous System / Q000503:physiopathology*; D013997:Time Factors