Role of MPI & FDG-PET in the assessment of viable myocardium in patients with significant LV dysfunction

Patients with significant LV dysfunction and uncontrolled symptoms need intensive medical and surgical management. Myocardial perfusion imaging (MPI) and FDGPET scan can provide myocardial viability assessment. Method: Retrospective comparison of findings from Rest 99mTc Tetrofosmin MPI followed by 18F FDG-PET scan by Glucose loading protocol with the Echocardiography reports in the 5 segment myocardial model. Results: 13 males with mean age 55 ± 8.3 years and mean Echocardiography Ejection Fraction 24.6±6.4% were evaluated. 65 myocardial segments demonstrated 22 (34%) akinetic and 30 (46%) severely hypo-kinetic on Echocardiography. 17 (77%) of the 22 akinetic and 15 (50%) of the 30 hypo-kinetic segments demonstrated perfusion defects. 15 (68%) of the akinetic segments and 13 (43%) hypo-kinetic segments demonstrated matching perfusion-metabolism defects indicating scarred tissue. 5 (23%) akinetic and 15 (50%) hypo-kinetic segments demonstrated varying perfusion indicating viable myocardium. 2 (9%) akinetic and 2 (7%) hypo-kinetic segments showed perfusion metabolism mismatch indicating hibernating myocardium. 54% of the akinetic and hypo-kinetic segments were non-viable.

MPI and FDG-PET can provide reliable assessment of myocardial viability in akinetic and severely hypo-kinetic segments in patients with significant LV dysfunction.