Direct imaging of viable myocardium by gated SPECT in patients with ischaemic left ventricular dysfunction

Area of Science:

• Cardiology
• Nuclear Medicine
• Medical Imaging

Background:

• Ischaemic left ventricular (LV) dysfunction affects cardiac function and requires revascularization.
• Predicting functional recovery after revascularization is crucial for patient management.
• Gated SPECT imaging offers insights into myocardial viability and function.

Purpose of the Study:

• To evaluate a novel polar map of myocardial viability using gated SPECT.
• To assess the map's ability to predict functional recovery post-revascularization.
• To aid clinical decision-making in patients with ischaemic LV dysfunction.

Main Methods:

• 17 patients with ischaemic LV dysfunction underwent nitrate-enhanced gated SPECT before and after revascularization.
• A semiautomated method generated a viable myocardium (VIA) map by matching perfusion and motion polar maps.
• A recovery (REC) map was created by comparing pre- and post-revascularization motion polar maps.

Main Results:

• The VIA map identified 73% of segments as viable.
• Of dysfunctional viable segments, 75% showed improved LV function post-revascularization.
• The VIA map demonstrated high accuracy (85% concordance, 89% sensitivity, 75% specificity) in predicting functional recovery.

Conclusions:

• The proposed polar map from gated SPECT accurately predicts myocardial functional recovery.
• Perfusion/function matching provides a direct quantitative image of viability.
• This imaging technique can assist clinical decisions in ischaemic LV dysfunction management.