In situ diagnostics of myocardial diseases: prospects for optical biopsy

The method of laser-induced fluorescence was tested in the model of global ischemia and reperfusion by using isolated rat hearts. The device LAКK-M was used to register integral fluorescence signals. Induced radiation absorption peak and fluorescence intensity were significantly lower in the reperfusion suggesting lower degree, absorption rate, and radiation reflection. These characteristics imply the left shift of NAD+/NADH ratio which is one of key processes in ischemia and reperfusion injury. The method of laser-induced fluorescence is significantly sensitive to changes in this ratio. It allows for real-time registration of myocardial viability and may represent promising in situ diagnostic modality for myocardial diseases.