PULSATILE ASPECTS OF CORONARY SINUS BLOOD FLOW IN CLOSED-CHEST DOGS

Phasic aspects of the velocity of coronary sinus blood flow were studied in closed-chest dogs by means of an electromagnetic flow measuring device located at the tip of a cardiac catheter. In agreement with observations in open-chest dogs, it was noted that flow was predominantly systolic, and the wave form was characterized by marked variability. Peak flow velocity occurred at various phases of systole. Small presystolic reversals of coronary sinus flow seemed to occur occasionally in some dogs. Cyclic respiratory changes of coronary sinus blood velocity were not infrequently observed. This study demonstrates a suitable method for the measurement of the velocity of flow within the coronary sinus of closed-chest animals, and perhaps, more importantly, demonstrates a method potentially applicable to human subjects. © 1969.