[Clinical estimation of the relation between coronary artery disease and regional myocardial blood flow by continuous thermodilution with the multithermistor catheter].

To evaluate coronary hemodynamics more precisely in ischemic heart disease, great cardiac vein flow ( GCVF ) and coronary sinus flow (CSF) were simultaneously measured before and during atrial pacing by a continuous thermodilution technique with the multithermistor catheter in 10 patients with significant coronary stenosis (narrowing of the left anterior descending artery of 75% or more) (Group 1: CAD) and 12 cases with the normal coronary artery (narrowing of 25% or less) (Group 2: NonCAD ). GCVF reflects the anterior regional flow of the left ventricle and CSF reflects total left ventricular flow. Between the two groups, no significant differences were noticed in either resting GCVF or resting CSF. However, atrial pacing induced a reduction of coronary resistance (CR) and increasing regional myocardial blood flow in both groups in the same way, and the maximal pacing provoked anginal episode in CAD group in which both the percent decrease of coronary resistance (CR) (% delta CRant 25.3% and % delta CRt 23.3%) and the percent increase of regional myocardial blood flow (% delta GCVF 49.6% and % delta CSF 40.6%) were lower than those in NonCAD group (% delta CRant 42.3%, % delta CRt 37.6%, % delta GCVF 80.6%, and % delta CSF 68.3%, respectively). These data imply that resting coronary blood flow may be maintained as normal in patients with angiographically significant coronary stenosis, though coronary reserve probably decreased in these patients. In this respect, the continuous thermodilution technique using the multithermistor catheter may be useful for the clinical estimation of coronary hemodynamics induced by various interventions. This technique can be performed repeatedly for a short time and permits simultaneous assessment of venous blood flow draining from the anterior wall and of total left ventricular flow.