[Experimental evaluation of the reliance of coronary sinus blood flow (CSF) and great cardiac vein blood flow (GCVF) measured by local thermodilution method].

A closed circuit was made to evaluate the reliance of coronary sinus blood flow (CSF) and great cardiac vein blood flow (GCVF) measured by local thermodilution method using multi-thermister catheter. The circuit consists of four parts: a constant-temperature water bath, a reservoir, a rotary pump and a polyethylene tube with a cock. Using this circuit and thermodilution catheters, flow rate was measured under various conditions. Measurements were repeated in changing injection rate of indicator, thermister interval of the catheter, diameter of the polyethylene tube and temperature difference between the room and the water bath. Indicator injection rate and thermister interval were important factors in flow rate measurement. Measured data and real flow were well correlated until 300 ml/min in injection rate of 40-50 ml/min. Other factors did not significantly influence the flow measurement. These results indicate that local thermodilution method is reliable if only injection rate of indicator and thermister interval are suitably settled.