Figure 3.

The logic of the heart rate variability (HRV)-based stress predictive model. All risk factors (stressors) have effects during the progression from transient ischemic attack (TIA) to the development of outcome events (ischemic stroke, TIAs, cardiovascular diseases, and vascular death). Autonomic nervous system (ANS) is directly affected by the risk factors/stressors; on the other hand, dysfunctional ANS activity conversely contributes to the development of risk factors/stressors. If correct, this model would suggest that whether HRV parameters (as markers of ANS) can predict the occurrence of secondary outcome events.