Abstract 15196: Dying inside the MR: an MR Imaging and 12-lead ECG Study of Stages of Acute Ventricular Ischemia Leading to Death
Background: An MR compatible 12-lead ECG, equipped with MRI noise removal hardware and Magnetohydrodynamic (MHD) voltage removal software , was previously applied to physiological monitoring of Premature Ventricular Contraction (PVC) and atrial fibrillation patients inside the MRI bore, as well as for synchronizing cardiac sequences. MHD removal improved ST segment visualization. The monitoring of patients with ischemic histories during imaging or MR guided intervention requires rapid detection of acute ischemia. In addition, MRI visualization of cardiac function during ischemia may enhance the understanding of its progression and lead to therapy improvement. Objectives: To perform Left Anterior Descending (LAD) artery occlusion in a swine inside MRI, detect ST elevation and perform MR imaging during the stages of ischemia from onset to death.
Methods: A 2-mm balloon catheter partially filled with Gd-doped water was inserted into a swine’s distal LAD under X-ray guidance. The swine was then moved to an MR suite equipped with the 12-lead ECG system and continuous ECG monitoring was performed. Multiphase wall-motion imaging was performed using 12-lead ECG synchronization. The balloon was inflated to 20 atmospheres (t=0 sec), followed by repeated MRI and ECG monitoring until death (t=1200 sec). Post-mortem high-resolution 3D T1 imaging confirmed balloon positioning, while T2-weighted imaging detected edema.
Results: 12-lead ECG detected ST elevation in V3-V5 t=1.5 sec after onset (Fig A), progressing to acute ischemia (Fig A2-3), bradycardia and death. Cine MRI (Fig C1-C4) detected progression of ventricular dysfunction, with periods of unusual flow vortexes. Epicardial edema was detected adjacent to the balloon (Fig D).
Conclusions: MR compatible 12-lead ECG rapidly detects acute ischemia, with MRI visualizing ichemia progression Ref: ZTH Tse, ISMRM ‘09-‘11 Acknowledgements: NIH U41-RR019703, R43 HL110427-01, AHA 10SDG261039
- © 2012 by American Heart Association, Inc.