Nighttime ambulatory blood pressure is associated with atrial remodelling and neurohormonal activation in patients with idiopathic atrial fibrillation.
OBJECTIVE
Hypertension is a risk factor for atrial fibrillation. Activation of the renin-angiotensin-system seems to be involved in atrial enlargement, with release of atrial and brain natriuretic peptides. The aim of this study was to evaluate the relationship between ambulatory blood pressure and levels of natriuretic peptides, with left atrial size in normotensives with idiopathic atrial fibrillation.


METHODS
This was a cross-sectional study in patients with idiopathic atrial fibrillation. The following measurements were recorded during the course of the study: office and 24-h ambulatory blood pressure, atrial and brain natriuretic peptides, plasma renin, aldosterone, and angiotensin-converting enzyme.


RESULTS
Forty-eight patients (mean age 55 [10] years; 70.6% male) were included in the study. Mean office sitting blood pressure values were 132.49 (14.9)/80.96 (9.2) mmHg. Mean 24-h ambulatory systolic and diastolic blood pressure values were 121.10 (8.3)/72.11 (6.8) mmHg (daytime, 126.8 [9.7]/77.58 [7.9] mmHg; nighttime, 114.56 [11.6]/68.6 [8.8] mmHg). A clear trend towards increased left atrial size with higher ambulatory blood pressure values was noted, which was statistically significant for nighttime values (r=0.34; P=.020 for systolic and r=0.51; p=.0001 for diastolic). A significant correlation between atrial natriuretic peptide and nighttime systolic (r=0.297; P=.047) and diastolic (r=0.312; P=.037) blood pressure was observed. Significant correlations were also observed between left atrial size and atrial natriuretic peptide levels (r=0.577; p<.0001) and brain natriuretic peptide levels (r=0.379; P=.012).


CONCLUSIONS
Nighttime blood pressure is associated with left atrial size and the release of natriuretic peptides in normotensive patients with idiopathic atrial fibrillation.
Unidad de Hipertensión y Riesgo Vascular, Servicio de Medicina Interna, Instituto de Medicina y Dermatología, Hospital Clínic (IDIBAPS), Universidad de Barcelona, Barcelona, Spain.
Mónica
M
Doménech
Unidad de Arritmias, Servicio de Cardiología, Instituto del Tórax, Hospital Clínic (IDIBAPS), Universidad de Barcelona, Barcelona, Spain.
Antonio
A
Berruezo
Unidad de Arritmias, Servicio de Cardiología, Instituto del Tórax, Hospital Clínic (IDIBAPS), Universidad de Barcelona, Barcelona, Spain.
Irma
I
Molina
Unidad de Arritmias, Servicio de Cardiología, Instituto del Tórax, Hospital Clínic (IDIBAPS), Universidad de Barcelona, Barcelona, Spain.
Lluis
L
Mont
Unidad de Hipertensión y Riesgo Vascular, Servicio de Medicina Interna, Instituto de Medicina y Dermatología, Hospital Clínic (IDIBAPS), Universidad de Barcelona, Barcelona, Spain. Electronic address: acoca@clinic.ub.es.
Antonio
A
Coca
D001281:Atrial Fibrillation / Q000503:physiopathology*; D064752:Atrial Remodeling; D001794:Blood Pressure / Q000502:physiology*; D018660:Blood Pressure Monitoring, Ambulatory; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D005260:Female; D006325:Heart Atria / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D018377:Neurotransmitter Agents / Q000378:metabolism*
D018377:Neurotransmitter Agents