[Evaluation of myocardial oxygen extraction dynamics in syndrome X by continuous measurement of coronary sinus oxygen saturation and its relation to clinical features].
We investigated the relation of myocardial oxygen extraction dynamics to pathophysiology and clinical features in syndrome X. In patients with syndrome X who underwent cardiac catheterization, coronary sinus oxygen saturation (n = 21) during rapid atrial pacing loading was continuously measured using a fiberoptic catheter system, and global and regional left ventricular function (n = 14) was evaluated before and immediately after pacing loading. Results were as follows: 1) In 5 of 21 patients with syndrome X, coronary sinus oxygen saturation during pacing loading fell less than 5% below the baseline without any impairments of global and regional left ventricular function. 2) In 16 patients with syndrome X, coronary sinus oxygen saturation during the pacing loading continuously fell over 5% below the baseline accompanied by impairment of both global and regional left ventricular function. The decrease in regional wall motion of the left ventricle was mainly observed in the apical area. These findings imply that changes in myocardial oxygen extraction dynamics in syndrome X during rapid atrial pacing may show the extent of a patchy area where myocardial oxygen demand-supply imbalance occurs due to coronary microcirculatory disturbances.
Mikuniya
A
A
Second Department of Internal Medicine, Hirosaki University School of Medicine.
Fujino
Y
Y
Higashiyama
A
A
Narita
T
T
Fukushi
T
T
Sasaki
M
M
Onodera
K
K
Sawai
M
M
Akitsu
H
H
Oike
Y
Y
D000328:Adult; D000368:Aged; D003326:Coronary Circulation; D003327:Coronary Disease / Q000503:physiopathology*; D003331:Coronary Vessels / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction; D009206:Myocardium / Q000378:metabolism*; D010101:Oxygen Consumption; D010138:Pacemaker, Artificial; D016277:Ventricular Function, Left