scholarly journals Coronary wave intensity during the Valsalva manoeuvre in humans reflects altered intramural vessel compression responsible for extravascular resistance

2012 ◽  
Vol 590 (18) ◽  
pp. 4623-4635 ◽  
Author(s):  
M. Cristina Rolandi ◽  
Froukje Nolte ◽  
Tim P. van de Hoef ◽  
Maurice Remmelink ◽  
Jan Baan Jr ◽  
...  
Keyword(s):  
Wave Intensity ◽  
Valsalva Manoeuvre ◽  
Extravascular Resistance

Waveform Shape Analysis: Extraction of Physiologically Relevant Information from Doppler Recordings

1994 ◽  
Vol 86 (5) ◽  
pp. 557-565 ◽  
Author(s):  
Margaret M. Ramsay ◽  
Fiona Broughton Pipkin ◽  
Peter C. Rubin ◽  
Robert Skidmore
Keyword(s):  
Laplace Transform ◽  
Pulsatility Index ◽  
Flow Characteristics ◽  
Resistance Index ◽  
Relevant Information ◽  
Peripheral Circulation ◽  
Valsalva Manoeuvre ◽  
Flow Conditions ◽  
Physiological Relevance ◽  
Healthy Female

1. Doppler recordings were made from the brachial artery of healthy female subjects during a series of manoeuvres which altered the pressure—flow characteristics of the vessel. 2. Changes were induced in the peripheral circulation of the forearm by the application of heat or icepacks. A sphygmomanometer cuff was used to create graded occlusion of the vessel above and below the point of measurement. Recordings were also made whilst the subjects performed a standardized Valsalva manoeuvre. 3. The Doppler recordings were analysed both with the standard waveform indices (systolic/diastolic ratio, pulsatility index and resistance index) and by the method of Laplace transform analysis. 4. The waveform parameters obtained by Laplace transform analysis distinguished the different changes in flow conditions; they thus had direct physiological relevance, unlike the standard waveform indices.

Sign in / Sign up

Export Citation Format

Share Document