1. different degrees of parasympathetic activity on sinus node.
Deceleration Capacity variants reflect
different degrees of parasympathetic activity on
sinus node.
Arsenos1 P., Manis2 G. , Gatzoulis1 K.A. , Tousoulis1 D.
1First Department of Cardiology and Electrophysiology Laboratory, Hippokration General Hospital, National and Kapodistrian University
of Athens, Athens, Greece.
2Department of Computer Science and Engineering, University of Ioannina, Ioannina. Greece.

2. Conflict of interest: None

3. Examination of Physiology of Heart Rate

4. Heart Rate physiology Generation of action potential in SAN Phase 4: The slope of depolarization is an important determinant of the rate of AP generation & heart rate max diastolic potential: mV Phase 0: inward Ca++ current Phase 1: there is generally no phase 1 in SAN Phase 2: brief plateau Phase 3: returns the cell to max diastolic repolarisation

5. Heart Rate physiology A
Heart Rate physiology A. intrinsic regulation If pacemaker current establishes the slope of spontaneous diastolic depolarization Intrinsic heart rate in healthy individuals during complete autonomic blockade =100 bpm

6. Heart Rate physiology The autonomic nervous system at the SAN Sympathetic limp: nor-adr, adr acceleration of HR Parasympathetic limp: muscarinic actions of Ach deceleration of HR

7. Heart Rate physiology
B. Extrinsic regulation physical activity response to mental activity sleep state through tonic activity of both limps of autonomic nervous system steepening the slope of spontaneous HR acceleration: diastolic depolarization Sympathetic limp: nor-adr, adr decrease in the slope of spontaneous HR deceleration: diastolic depolarization Vagus: muscarinic actions of Ach
Arsenos 2016

8. Arsenos 2016

9. Background:
Deceleration Capacity (DC) is an established total mortality predictor in post-MI patients.

10. Step 1. Definition of anchors. Step 2. Definition of segments. Step 3
Step 1. Definition of anchors Step Definition of segments Step Phase rectification Step Signal averaging Step Quantification of DC and AC.

12. Deceleration Capacity

13. DC=[x(0)+x(1) -x(-1)-x(-2) ]/4 Paradox negative values = acceleration!
Arsenos Thesis 2013

15. Goal: We hypothesized that
DCsgn and BBDC variants and the original DC method
reflect each one,
a different amount and analogy of ANS limps activity on sinus node.
Rate dependence of these three DC variants was investigated.

16. Methods:
Nineteen persons underwent Stress ECG test according Bruce protocol.
Holter ECG recordings performed including
pre-test resting ( 5 min),
stress test (12 min),
and recovery (10 min) periods.
Heart rate, RR duration, DCorig, DCsgn, BBDC indices were extracted for three different heart rate periods:
1st : RR=400ms, nd : RR =600ms, 3rd : RR=900ms.

17. Results: DCorig (ms) DCsgn (ms) BBDC (ms) RR:400ms 1.5 2.5 3.9
3.6
4.0
4.7
RR:900ms
9.7
8.7

18. Conclusions:
During fast heart rates (RR=400ms) BBDC presents the higher DC values.
During lower heart rates (900ms) it is DCorg that present the higher DC values.

19. Conclusions:
During fast heart rates (RR=400ms) BBDC presents the higher DC values.
During lower heart rates (900ms) it is DCorg that present the higher DC values.
DCorig (ms)
DCsgn (ms)
BBDC (ms)
RR:400ms
1.5
2.5
3.9
RR:600ms
3.6
4.0
4.7
RR:900ms
9.7
8.7
3.9
9.7

20. Considering the vagus nerve function with fast achetylcholine release to the simus node and its short time effect on sinus node function (<400ms),
BBDC with its beat to beat calculation algorithm, reflects probably in a higher analogy the vagus activity than DCorig and DCsgn.

21. DCorig and DCsgn variants
probably reflect net parasympathetic and sympathetic effects
on sinus node.
BBDC is the nearest to parasympathetic activity DC variant.

22. Thank you