Non-invasive assessment of coronary arterial tone using trans-thoracic Doppler echocardiography.
BACKGROUND
As coronary flow velocity (CFV) is inversely related to the luminal size that exists for the myocardial bed, the elevated arterial tone can be assessed as the higher flow velocity in the epicardial artery. We examined the usefulness of transthoracic Doppler echocardiography (TTDE) for the assessment of coronary arterial tone.


RESULTS
A total of 32 patients underwent TTDE and angiography. The luminal diameter (LD) in the left anterior descending artery (LAD) was measured by using quantitative coronary angiography before and after nitroglycerin (NTG) administration. The ratio of post NTG LD to the control (LD(NTG/Pre)) was assessed as a standard parameter of coronary arterial tone. We also measured CFV and CFV reserve (CFVR) at the LAD by TTDE. We evaluated the change of CFV (CFV(NTG/Pre)) and CFVR (CFVR(NTG/Pre)) following NTG administration. The LD increased from 1.98+/-0.46 to 2.51+/-0.34 mm (p<0.001), while the CFV decreased from 23.9+/-10.0 to 16.3+/-5.6 cm/s (p<0.03), and the CFVR increased from 2.39+/-0.65 to 3.56+/-1.12 (p<0.001). There were significant correlations between CFV(NTG/Pre) and LD(NTG/Pre) (p<0.0001, R2 = 0.532), and between the CFVR(NTG/Pre) and LD(NTG/Pre) (p<0.0001, R2 = 0.715).


CONCLUSIONS
TTDE can assess the coronary arterial tone by measuring the responses of CFV and CFVR to NTG administration.
Department of Cardiology, Tokyo Women's Medical University, Japan. mtakagi@hij.twmu.ac.jp
Atsushi
A
Takagi
Yukio
Y
Tsurumi
Kotaro
K
Arai
Yasuhiro
Y
Ishii
Kyomi
K
Tanimoto
Naoko
N
Ishizuka
Hiroshi
H
Kasanuki
D000328:Adult; D000368:Aged; D001783:Blood Flow Velocity / Q000187:drug effects; D017023:Coronary Angiography; D003331:Coronary Vessels / Q000000981:diagnostic imaging* / Q000187:drug effects / Q000503:physiopathology*; D004452:Echocardiography; D015150:Echocardiography, Doppler; D005260:Female; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D005996:Nitroglycerin / Q000494:pharmacology; D014665:Vasodilator Agents / Q000494:pharmacology
D014665:Vasodilator Agents; D005996:Nitroglycerin