Adenosine-recruitable flow reserve is absent during myocardial ischemia in unanesthetized dogs studied in the basal state.

We conducted the present study to determine if pharmacologically recruitable flow reserve was present during ischemia in unanesthetized dogs studied in the absence of adrenergic activation. Microsphere measurements of regional perfusion at reduced coronary pressures in a distal circumflex region subjected to intracoronary adenosine infusion (0.265 mg/min IC) were compared with measurements in a proximal circumflex region where pressure was reduced but flow was being autoregulated normally.