Pulse wave analysis

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2. Jafar Al-Said, M.B. ChB. MD. FASN. FACP. Chair of Internal Medicine. Nephrology and Internal Medicine Consultant. Bahrain Specialist Hospital PULSE WAVE ANALYSIS, PULSE WAVE VELOCITY AND CENTRAL BLOOD PRESSURE EUROPEAN HYPERTENSION EXELLENCE CENTER BAHRAIN SPECIALIST HOSPITAL 2

3. Scheme Sphygmomanometer. Pulse wave hemodynamics. Incident wave & Reflected wave. Augmentation pressure. Central Pressure. Pulse wave analysis. Pulse wave Velocity. How to check the Central pressure. Evidenced based clinical significance. PWA and Central BP research data from BSH European HTN excellence center data. Conclusion. 3

4. Measurement of the BP Korotkoff sounds of BP measurement. Discovered By Nocolas K orotkoff 1905. BP CUFF PICTURE. en.wikipedia.org/wiki/ Korotkoff _ sou Wikipedia 4

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6. Telecommunication and Mail 1900 6

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9. 9 CARDIAC CYCLE AND PRESSURE ALTERATION

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12. Schematic representation of pulse pressure amplification. Oliver J J , and Webb D J Arterioscler Thromb Vasc Biol. 2003;23:554-566 Copyright © American Heart Association, Inc. All rights reserved. 12

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15. Affect of Atherosclerosis on blood flow 15

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17. Aorta and Central Arteries INCIDENT WAVE REFLECTIVE WAVE 17

18. 18 Arterial system is a closed system Primary wave (blue) travels along the arteries generating reflected waves from bifurcations These small reflected waves return to the heart, summing to create a reflected pressure wave as shown in grey, starting even before the end of systole Figure 2 Physiology - Pressure Wave Reflection at the Heart

19. 19 Central pressure waveform) is the sum of the outgoing and reflected wave (the green wave at left) Figure 3 Pressure Wave Reflection at the Heart

20. 20 S P AP PP DP Systolic pressure (SP) Diastolic pressure (DP) Central Pulse Pressure (PP) Augmented pressure (AP) “ measure of the energy “wasted” by the heart due to the reflected wave” AIx (= AP/PP) “ composite measure of the magnitude of wave reflection and arterial stiffness” Key Central pressure parameters.

21. 21 With stiffer arteries, the reflected wave arrives back at the heart sooner, adding to (i.e. augmenting) the outgoing wave Now there is a very different Central Pressure Waveform (the green wave) These features in the waveform can be measured, and have predictive value. Figure 5 Pressure Wave Reflection at the Heart

22. Aortic Pulse wave Analysis Figure 1: Aortic pulse pressure waveform. Systolic and diastolic pressures are the peak and trough of the waveform. Augmentation pressure is the additional pressure added to the forward wave by the reflected wave. Augmentation index is defined as the augmentation pressure as a percentage of pulse pressure. The dicrotic notch represents closure of the aortic valve and is used to calculate ejection duration. Time to reflection is calculated as the time at the onset of the ejected pulse waveform to the onset of the reflected wave. 22

23. Faster reflected time. Added to systole 23

24. Schematic representation of pulse pressure amplification. Oliver J J , and Webb D J Arterioscler Thromb Vasc Biol. 2003;23:554-566 Copyright © American Heart Association, Inc. All rights reserved. 24

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26. Central Arterial Pressure Wave Analysis of the pressure waveform. The initial systolic pressure is labelled as P1 and augmented pressure (DeltaP) is typically measured as the difference between peak pressure (P2) and P1. Augmentation index is DeltaP/PP. PP, pulse pressure. 26

27. Aging and changes in the pulse wave 27

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29. ESH guidelines 2013 29

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31. 31 In the CAFE study of over 2,000 patients, brachial blood pressure was controlled in both study arms But the ACE/ CCB arm had up lower central BP and 30% less CV events than the beta blocker arm. Augmented Pressure was reduced by the ACE/ CCB but not by the beta blocker. Brachial pressure does not measure arterial stiffness Central Pressure shows the effects of Drug therapy masked by Brachial Pressure Williams B et al., Circulation 2006; 113: 1213-25

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36. Central Pulse P ressure is better than brachial pressure in determining CV risk. Strong Heart Study showed that central pulse pressure (CPP) defines a threshold for CV risk: Below 50 mmHg- Risk of heart attack or stroke was normal. Above 50 mmHg– there were twice as many heart attacks and stokes when CPP exceeded 50mmHg. * NS from Q1 ** p<0.003 from Q1 Roman MJ et al., Circulation 2008 118: S1165 Brachial pulse pressure does not show a similar threshold 36

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40. Final analysis Report 40

41. Patient with CKD IV 41

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45. BSH study on PWA and Central BP Aim: 1-Is their a significant difference between the Brachial and Central: Systolic. Dialysis. Pulse Pressure. MAP . 2-Independent variables affecting the Augmentation pressure and the Augmentation Pressure Index. 45