Is abnormal heart rate variability a specific feature of congestive heart failure?

In conclusion, a variety of pathophysiologic conditions characterized by neurohumoral activation such as CHF and appropriate sinus tachycardia have similar, but not identical, effects on HR, and traditional as well as nonlinear indexes of HR dynamics. Although, these pathophysiologic conditions could produce different effects on the degree of vagal and sympathetic activity, the overall effect is probably similar. Moreover, differences in HR and HRV in these abnormal states could be explained by differences in the magnitude of the stimulus.