Quantitative assessment of coronary artery stenosis by intravascular Doppler catheter technique. Application of the continuity equation.

Abstract

Application of the continuity equation to Doppler catheter measurement of coronary flow velocity can be used to successfully compute the severity of coronary stenoses. This may be a useful alternative method to estimate functional severity of coronary artery disease, although further technical developments will be necessary to improve the sensitivity.

The application of breath hold phase velocity mapping techniques to the measurement of coronary artery blood flow velocity: Phantom data and initial in vivo results

“…For these studies, the peak flow velocity and the maximum rate of change of peak flow velocity through the unstenosed part of the phantoms was approximately 15 cmls and 40 cmlsZ, respectively. Although this value of acceleration is lower than the maximum found in a normal coronary artery, in vivo stenosis assessment would initially be performed in diastole, when the arterial velocity time curve is relatively flat and acceleration correspondingly low (31)(32)(33)(34)(35)(36).…”

“…However, this approach presents potentially more problems with vessel tortuosity and motion and these are currently under investigation in phantom studies. Further in vitro work is also necessary to validate the technique under a range of pulsatile flow conditions, reflecting the wide range of blood flow velocities and accelerations found in coronary arteries in vivo (31)(32)(33)(34)(35)(36). The in vitro studies described in this report were performed in phantoms with internal lumen diameters of 5.6 mm (3.5 pixels), representing coronary artery diameters at the upper end of the normal range (37).…”

Intravascular Ultrasound Doppler Measurement of Blood Flow Velocity

“…IVDS using a catheter was investigated mainly in the coronary artery in previous studies. 10,11 This study is the first to apply this modified technique in the neurovessels and extremity vessels using the Doppler micro-guide wire system. Compared with other systems usually with a diameter of 0.46 mm (0.018 in.…”

“…was developed. Therefore, a renewed investigation of intravascular Doppler sonography (IVDS) using such a microprobe in the form of either Doppler microguide wire [5][6][7][8] or Doppler catheter [9][10][11] gained importance.…”

Angiographically borderline left main coronary artery lesions: correlation of transthoracic doppler echocardiography and intravascular ultrasound: a pilot study

“…Although it provides detailed anatomical information on the vessel lumen, it is an expensive and invasive procedure. Several other diagnostic tools, such as myocardial perfusion scintigraphy [14,15], stress echocardiography [16], multidetector computed tomography [17] and coronary flow reserve measurement [18,19] have been proposed as valuable adjunct to coronary angiography in the difficult clinical decision making process of patients with borderline LM lesions. It has also been demonstrated, that simple resting Doppler transthoracic echocardiography (TTDE) is an effective method in assessing hemodynamically significant LM lesions [20-22].…”