Cardiac-specific sympathetic activation in men and women with and without heart failure.
BACKGROUND
Clinical outcomes for cardiovascular syndromes such as heart failure differ between men and women.


OBJECTIVE
To seek phenotypic evidence for sex-differences in cardiac-specific sympathetic nervous system activation, as abnormal sympathetic nervous system activation is a key pathophysiological mechanism in heart failure (HF).


METHODS
Patients who underwent evaluation of cardiac norepinephrine spillover (CNESP) using radiotracer methodology were identified retrospectively, and included in the analysis if they met criteria for either a normal left ventricular (NLV) function group, or systolic HF group, defined as an LV ejection fraction <40% and NYHA class II-III symptoms. Within each group a matched cohort analysis, identifying two control men for each woman, was performed.


RESULTS
166 subjects were identified, 48 within the NLV function group and 118 within the HF group. In the NLV function group, 12 women were matched for age to 24 men. Women had significantly higher NE concentrations in coronary sinus plasma. When normalised to total body NE spillover (CNESP:TBNESP), women had significantly higher values than men (CNESP:TBNESP, 6±3% in women vs 3±3% in men, p<0.05). In the HF group, 20 women were matched for age, date of study and presence of coronary disease to 39 men. There were no differences in comorbidities, drugs or haemodynamic measurements. Both CNESP and CNESP:TBNESP were significantly higher in women with HF than in men (CNESP 264±191 in women vs 182±110 in men, CNESP:TBNESP 9±6% in women vs 4±2% in men, p<0.05 for both).


CONCLUSIONS
In patients with and without HF, women exhibit increased cardiac-specific sympathetic activation. Sexual dimorphism in cardiac autonomic physiology and its relationship to disease merits further investigation.
Mitoff
Peter R
PR
Mount Sinai Hospital, 600 University Avenue, Toronto, Ontario, Canada.
Gam
Daniel
D
Ivanov
Joan
J
Al-hesayen
Abdul
A
Azevedo
Eduardo R
ER
Newton
Gary E
GE
Parker
John D
JD
Mak
Susanna
S
D000368:Aged; D001342:Autonomic Nervous System Diseases / Q000150:complications* / Q000503:physiopathology; D005260:Female; D006333:Heart Failure / Q000209:etiology* / Q000503:physiopathology; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000378:metabolism; D009638:Norepinephrine / Q000378:metabolism; D012189:Retrospective Studies; D012737:Sex Factors; D018487:Ventricular Dysfunction, Left / Q000209:etiology / Q000503:physiopathology
D009638:Norepinephrine