Advanced technique of myocardial no-reflow quantification using indocyanine green.

The post-ischemic no-reflow phenomenon after primary percutaneous coronary intervention (PCI) is observed in more than half of subjects and is defined as the absence or marked slowing of distal coronary blood flow despite removal of the arterial occlusion. To visualize no-reflow in experimental studies, the fluorescent dye thioflavin S (ThS) is often used, which allows for the estimation of the size of microvascular obstruction by staining the endothelial lining of vessels. Based on the ability of indocyanine green (ICG) to be retained in tissues with increased vascular permeability, we proposed the possibility of using it to assess not only the severity of microvascular obstruction but also the degree of vascular permeability in the zone of myocardial infarction.

visualization and quantification of experimental myocardial infarction by indocyanine green fluorescence imaging.

The fluorophore indocyanine green accumulates in areas of ischemia-reperfusion injury due to an increase in vascular permeability and extravasation of the dye. The aim of the study was to validate an indocyanine green-based technique of in vivo visualization of myocardial infarction. A further aim was to quantify infarct size ex vivo and compare this technique with the standard triphenyltetrazolium chloride staining.

Autofluorescence spectroscopy for NADH and flavoproteins redox state monitoring in the isolated rat heart subjected to ischemia-reperfusion.

Background: Reduction of myocardial ischemia-reperfusion injury in the patients undergoing cardiac surgery under cardiopulmonary bypass represents an important goal. Intraoperative monitoring of myocardial metabolic state using continuous registration of nicotinamide adenine dinucleotide (NADH) and flavin adenine dinucleotide (FAD) fluorescence might contribute to the solution of the problem. The successful application of fluorescent spectroscopy in the clinical field requires additional refinement of the technique, particularly using excitation of both NADH and FAD with different wavelengths.