Background: The purpose of this study was to determine the influence of left ventricular (LV) hypertrophy and geometry on the diagnostic accuracy of wall motion and additional perfusion imaging during high-dose dobutamine/atropine stress magnetic resonance for the detection of coronary artery disease.
Methods and results: Combined dobutamine stress magnetic resonance (DSMR)-wall motion and DSMR-perfusion imaging was performed in a single session in 187 patients scheduled for invasive coronary angiography. Patients were classified into 4 categories on the basis of LV mass (normal, ≤ 81 g/m(2) in men and ≤ 62 g/m(2) in women) and relative wall thickness (RWT) (normal, <0.45) as follows: normal geometry (normal mass, normal RWT), concentric remodeling (normal mass, increased RWT), concentric hypertrophy (increased mass, increased RWT), and eccentric hypertrophy (increased mass, normal RWT). Wall motion and perfusion images were interpreted sequentially, with observers blinded to other data. Significant coronary artery disease was defined as ≥ 70% stenosis. In patients with increased LV concentricity (defined by an RWT ≥ 0.45), sensitivity and accuracy of DSMR-wall motion were significantly reduced (63% and 73%, respectively; P<0.05) compared with patients without increased LV concentricity (90% and 88%, respectively; P<0.05). Although accuracy of DSMR-perfusion was higher than that of DSMR-wall motion in patients with concentric hypertrophy (82% versus 71%; P < 0.05), accuracy of DSMR-wall motion was superior to DSMR-perfusion (90% versus 85%; P < 0.05) in patients with eccentric hypertrophy.
Conclusions: The accuracy of DSMR-wall motion is influenced by LV geometry. In patients with concentric remodeling and concentric hypertrophy, additional first-pass perfusion imaging during high-dose dobutamine stress improves the diagnostic accuracy for the detection of coronary artery disease.