Article

Although a higher heart rate is associated with an increased risk of
cardiovascular disease, the mechanism is not well understood. As thrombosis has
an important role in plaque development and acute coronary syndromes, the
increase related to heart rate may result from a prothrombotic imbalance. Methods
We investigated the relation between heart rate and thrombotic potential in 3451
participants from the Offspring Cohort of the Framingham Heart Study (mean age 54
years, 55% women). Participants were divided into quintiles based on heart rate
derived from a resting electrocardiogram. Results Higher heart rates were
associated with significant age-adjusted increases in fibrinogen, viscosity,
factor VII antigen, and impaired fibrinolytic potential (plasminogen activator
inhibitor and tissue plasminogen activator antigen) among men and women, and von
Willebrand factor antigen among men. Fibrinogen levels were 9% higher among men
with a heart rate of 80.9 +/- 8.1 beats/min (quintile 5) vs. 50.0 +/- 3.9
beats/min (quintile 1) (314 vs. 287 mg/dl, p < 0.001 for linear trend) and 13%
higher among women (83.5 +/- 7.7 beats/min vs. 53.7 +/- 3.5 beats/min (330 vs.
291 mg/dl, p < 0.001). The significant relations persisted after multivariate
adjustment, other than among men, in whom factor VII was not significant and
fibrinogen was borderline significant ( p = 0.065). Conclusions Higher heart
rates are associated with a prothrombotic state. Because these factors are also
associated with endothelial dysfunction and inflammation, these findings are
consistent with an injurious effect of higher heart rates on the endothelium.
Measures to reduce thrombotic potential may be of particular value in people with
higher heart rates.

Langue : ANGLAIS