Positive effect of sublingual nitroglycerin on performance of non-contrast enhanced magnetic resonance coronary angiography

Abstract

Background Cardiac magnetic resonance imaging (CMR) is increasingly proposed for non-invasive detection of relevant coronary artery disease (CAD), currently using an integrated assessment of myocardial perfusion, viability and function. Magnetic resonance coronary artery imaging (MRCA) is still experimental. Currently, it is not proven if sublingual nitroglycerin (slNitro) should be given to enhance performance of MRCA. Methods 15 volunteers, 9 (60%) of them male, mean age 37.2 years (±11) without known CAD underwent MRCA, without and with slNitro. slNitro dosage was adjusted according to blood pressure (systolic blood pressure (BP) >180 mmHg =>1.6 mg glyceroltrinitrat, BP 140-179 mmHg =>1.2 mg, BP 100-139 mmHg =>0.8 mg, BP 90-100mmHg =>0.4mg). All volunteers were examined in supine position using a GE Signa HDxt 1.5 Tesla scanner, equipped with EchoSpeed gradients, and a dedicated 8-element phased array cardiac coil (GE Healthcare, Milwaukee, Wisconsin). For imaging of the coronary arteries a commercially available whole heart 3D navigator gated multislab steady state free precession sequence (3D HEART, based on 3D FatSat FIESTA) without the administration of contrast medium was employed. This sequence is designed for free breathing cardiac MR angiography, using a navigator echo pulse that detects motion of the diaphragm. We used an abdominal belt in all vol to reduce motion of the diaphragm. Post processing was perfomed with cvi 42 5.0 (Circle, Calgary, Canada). Vessel diameter was measured before and after slNitro. Image quality was graded visually before and after slNitro on a 4-point scale: 1 = non-assessable with severe image artifacts, poor vessel contrast; 2 = assessable with