Measurement of myocardial oxygen tension: a valid and sensitive method in the investigation of transmyocardial laser revascularization in an acute ischemia model.
BACKGROUND
The effect of transmyocardial laser revascularization (TMLR) on microperfusion and oxygen supply was studied in an acute ischemia model, using 35 pigs, with 13 serving as controls.


METHODS
Measurement of tissue oxygen tension was compared with the semiquantitative measurement of microperfusion using contrast echocardiography and infrared laser Doppler. All methods were used before and after coronary occlusion and after TMLR. Effects were measured in the ischemic area and in two ischemia independent areas.


RESULTS
At baseline, oxygen partial pressure was 54.2 +/- 15.7 mmHg and decreased to 2.8 +/- 1.4 mmHg ( P < 0.05) after occlusion. After TMLR, oxygen tension increased to 27.3 +/- 8.5 mmHg ( P < 0.05) in the ischemic area, indicating a significant effect of TMLR on microperfusion and oxygen tension. Changes in regional oxygen tension corresponded to Levovist density changes in contrast echocardiography and changes in microperfusion measured by infrared laser Doppler.


CONCLUSIONS
Our data indicate that measurement of tissue oxygen tension is a suitable experimental tool to assess the effect of TMLR on myocardial perfusion, which cannot be discriminated using clinical imaging methods.
Heidt
M C
MC
Department of Cardiology, University Clinic Giessen, Giessen, Germany. Martin.C.Heidt@innere.med.uni-giessen.de
Sedding
D
D
Stracke
S K H
SK
Stadlbauer
T
T
Boening
A
A
Vogt
P R
PR
Schönburg
M
M
D000208:Acute Disease; D000818:Animals; D003287:Contrast Media; D003326:Coronary Circulation; D004195:Disease Models, Animal; D004452:Echocardiography / Q000379:methods; D004563:Electrochemistry / Q000295:instrumentation; D017736:Ion-Selective Electrodes; D053685:Laser Therapy; D017078:Laser-Doppler Flowmetry; D054018:Lasers, Excimer; D008297:Male; D008833:Microcirculation; D017202:Myocardial Ischemia / Q000000981:diagnostic imaging / Q000378:metabolism / Q000503:physiopathology / Q000601:surgery*; D009204:Myocardial Revascularization / Q000379:methods*; D009206:Myocardium / Q000378:metabolism*; D010100:Oxygen / Q000097:blood / Q000378:metabolism*; D010313:Partial Pressure; D011134:Polysaccharides; D015203:Reproducibility of Results; D013552:Swine
D003287:Contrast Media; D011134:Polysaccharides; C059891:SHU 508; D010100:Oxygen