Clinical application of MRI tagging for detection of left ventricular asynergic wall after myocardial infarction

Objective To estimate the clinical value of MRI tagging in the diagnosis of asynergic zones of left ventricular aneurysm (LVA). Methods Twelve patients presenting with formerly typical symptoms of AMI along with abnormal Q waves on ECG and diagnosed angiographically as coronary artery disease (CAD) with LVA underwent MRI examination applying tagging sequence in combination with late-delayed enhancement (LDE) evaluation to observe the morphological and functional characteristics of asynergic segments after AMI. Results MRI tagging technique can visualize distinctly three patterns of ventricular wall motion: kinetic, akinetic and dyskinetic in 10/12 patients (success rate 83%). By comparing with LDE images, in 6/16 akinetic segments, we found no signs of myocardial infarction including intramural hyper-enhancement or wall thinning, implying that these regions reflected reversibly ischemic injury (such as hibernation or stunning) which had the potential of functional recovery after surgical revascularization without the need of exclusion in the LVA repair procedure. Meanwhile, we also found that in 5 longitudinally akinetic zones, tagging can demonstrate the existence of radial contractility, showing the possibility of postoperative revitalization. Conclusion The clinical analysis of MRI tagging results can differentiate among the various conditions of regional ventricular-wall function in LVA or remote myocardium and provide more valuable information to further surgical treatment of LVA.