The effect of acute changes in coronary blood flow on left ventricular end-diastolic wall thickness. An...

The effect of acute alterations in coronary blood flow (CBF) on left ventricular (LV) end-diastolic wall thickness was measured by reflected ultrasound in twelve anesthetized dogs. During five minutes of coronary ligation, wall thickness decreased from a control of 9.0 +/- 0.3 mm to 8.1 +/- 0.3 mm (P less than 0.001); during reperfusion (reactive hyperemia), wall thickness was greater than control (10.2 +/- 0.2 mm at one minute, P less than 0.001). Increased CBF produced by intracoronary nitroglycerin or papaverine resulted in transient increases in wall thickness from 8.9 +/- 0.1 mm to 9.7 +/- 0.2 at one minute (P less than 0.001) and 10.0 +/- 0.6 mm to 11.2 +/- 0.7 mm at one minute (P less than 0.001), respectively. The observed direct relation between CBF and wall thickness suggests a dynamic role for CBF in calculations of LV mass, diastolic wall stress, and myocardial stiffness constants.