Adenosine infusion is accompanied by increases in coronary blood flow and myocardial bllood volume. Myocardial blood volume may produce changes in diastolic left ventricular (LV) performance by increasing myocardial turgor. Diastolic dysfunction may also be the result of myocardial ischemia. The relation between changes in LV mass and diastolic function has not been previously investigated. this study examined the relation between changes in LV mass during adenosine-induced coronary hyperemia and LV diastolic function. Serial two-dimensional and Doppler echocardiographic measurements were made before, during, and after adenosine infusion (140 μg/min for 6 min) in 21 patients with (group 1) and 10 patients without (group 2) coronary artery disease (CAD). The LV mass and transmitral diastolic filling indexes were determined from digitized images from apical four-chamber view. Adenosine infusion produced a greater increase in LV mass in group 2 than in group 1 (29% + 11% vs 9% + 6%, p < 0.0002). The ratio of transmitral early (E) to atrial (A) filling velocity ( E A) increased 10% + 16% in group 2 and decreased 8% ± 20% in group 1 (p < 0.02), and the velocity time integral of early filling increased 11% ± 52% in group 2 and decreased 20% ± 31% in group 1 (p < 0.04). There was a correlation between the change in E A ratio and the LV mass (r = 0.53, p < 0.003). Thus adenosine infusion caused a greater increase in LV mass in normal subjects than in patients with CAD. There were also changes in Doppler-derived indexes of diastolic LV function. The diastolic dysfunction in CAD cannot be entirely the result of increased myocardial turgor. © 1995.