Table 1.

Techniques to study myocardial viability

Technique	Imaging finding	Criteria for viability
Echocardiography
	Left ventricular wall thickness Inotropic contractile reserve	>6 mm [9] Biphasic response better predictive accuracy versus monophasic response [14]
	Contrast echocardiography perfusion imaging Strain and strain rate imaging	No perfusion defect [16] Global left ventricular strain of −13.7% on automated function imaging [13]
Cardiac MRI
	Left ventricular wall thickness Inotropic contractile reserve LGE	>5.5 mm [22] Improved contractility [22] <25% transmural LGE 26–50% transmural LGE intermediate recovery [31]
Radionuclide techniques
SPECT
Thallium-201	Perfusion Redistribution	>50% peak levels [38, 39] >50% peak levels [38, 39]
Technetium-99m	Perfusion	>50% peak levels [39]
Nitrate-enhanced perfusion imaging	Perfusion	>50% peak levels [36]
Low-dose dobutamine	Contractile reserve	Improvement in regional wall motion with low-dose dobutamine [38]
PET
F-18 FDG	Glucose uptake	>50% peak activity

LGE late gadolinium enhancement

The techniques of strain and strain rate imaging, 3D echocardiography, BMIPP SPECT, C-11 acetate and palmitate PET, and delayed contrast enhancement using MDCT are currently under investigation and criteria for viability are not well established