Table 2.

Common output measurements for in vivo MI and MI/reperfusion studies

Measurement	Information Provided
Infarct size	Infarct size (MI)
	Infarct size per area at risk (MI/reperfusion)
	Initial ischemic stimulus
	Final area of damage
	Effect of therapy or intervention
Plasma biomarkers	Ischemia: creatine kinase, troponins
	Inflammation: cytokines and chemokines
	Scar formation: growth factors and the ECM
	Neovascularization: angiogenic factors
Left ventricular physiology (echocardiography, MRI, positron emission tomography imaging)	Geometry and function: dimensions, wall thickness, left ventricular dimensions and volumes, fractional shortening, ejection fraction, remodeling index
	Electrophysiological function: PR, QRS, and QT intervals/morphology; spontaneous and inducible arrhythmias
Inflammation	Immunohistochemistry and immunoblot analysis for cell numbers and inflammatory protein expression
	Flow cytometry analysis of the digested myocardium for individual cell phenotypes
	Gene expression
	Systemic and circulating inflammation
ECM scar	Picrosirius red for collagen deposition
	Immunohistochemistry and immunoblot analysis for ECM proteins and cross-linking enzymes
	Gene expression
	Scar strength assessment
Neovascularization	Blood vessel numbers
	Vessel type and quality
Microvascular damage	Microvascular plugging
	Hyperpermeability/edema
	Hemorrhage

MI, myocardial infarction; ECM, extracellular matrix; MRI, magnetic resonance imaging.