Article Text
Abstract
Objective Wave intensity analysis is a method that allows separating pulse waves into components generated proximally and in the periphery of arterial trees, as well as characterising them as accelerating or decelerating. The early diastolic suction wave (eaDSW) is one of the most prominent wave events in the coronaries. The aim of this study was to determine whether (1) microvascular dilatation directly influences its energy, (2) stenosis severity can be assessed proximal to stenoses, (3) distal pulse wave entrapment exists in the presence of stenoses and (4) coronary collaterals influence wave entrapment.
Methods In 43 coronary artery disease patients, Doppler flow velocity and pressure measurements were performed in a proximal coronary segment at rest, in a distal segment at rest, during adenosine-induced hyperaemia and during balloon occlusion. Wave energies were calculated as the area under the wave intensity curves.
Results The eaDSW energy showed a significant increase during hyperaemia, but did not differ between proximal and distal segments. There was no significant correlation between eaDSW energy and coronary stenosis severity. Pulse wave entrapment could not be observed consistently in the distal segments. Consequently, the effect of coronary collaterals on pulse wave entrapment could not be studied.
Conclusions Microvascular dilation in the coronary circulation increases distal eaDSW energy. However, it does not show any diagnostically useful variation between measurement sites, various stenosis degrees and amount of collateral flow. The assessment eaDSW and its reflections were not useful for the quantification of coronary stenosis severity or the collateral circulation in clinical practice.
- coronary haemodynamics
- coronary artery disease
- wave intensity analysis
- coronary stenosis
- coronary collateral circulation
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Footnotes
Contributors *SFdM: planning, construction of measurement equipment, software writing, data acquisition, data analysis and manuscript preparation. CG, SG and TT: patient recruitment, data acquisition and data analysis. SC: patient recruitment and data acquisition. RV: planning, patient recruitment and data acquisition. KG: preliminary in vitro tests, construction of measurement equipment, software writing and data acquisition. *CS: planning, data acquisition, data analysis and manuscript preparation. The authors marked with * are responsible for the overall content as guarantors.
Funding This study was supported by a grant of the Swiss National Science Foundation (SNF 32003B_163256/1).
Competing interests None declared.
Patient consent for publication Not required.
Ethics approval The protocol was accepted by the Ethics Committee of the Kanton of Bern, Switzerland (KEK-#145/09).
Provenance and peer review Not commissioned; externally peer reviewed.
Data availability statement Data are available on reasonable request.