[Effect of changes of the left ventricular diastolic pressure on the coronary circulation hemodynamics]

In order to understand the effect of LVEDP changes caused by contrast injection during angiography on coronary hemodynamics we studied 15 patients (5 congestive CMP, 5 mixed angina and 5 controls). Our results do not cope with an important negative role played from LVEDP changes on coronary hemodynamics and cardiac metabolism. Actually LVEDP increase after ventriculography was balanced by coronary flow increase and impedance reduction even when the latter has been matched with LVEDP. We also observed lactate metabolism changes which are not likely to be provoked by myocardial ischemia, since there was not a definite negativization of % lactate extraction and delta A-VO2 always turned to reduction; this is apparently not in agreement with other Authors who had reported metabolic alterations suggestive for myocardial ischemia, even if they did not calculate delta A-VO2 and coronary flow. This difference could be related to the different populations studied, specially when considering the different functional meaning of coronary stenoses of the same degree at angiography. Is thus the Authors' thought that, when coronary reserve is still adequate, is it possible not to take into account LVEDP, which becomes important in patients with a more advanced coronary disease as in those cases this extravascular impedance factor to coronary flow could take his own worsening role.