In Vivo Monitoring der Vitalitat von Herzgewebe durch die kombinierte Aktivitat

A prototype system for in vivo monitoring of the heart tissue viability by using combined measurements of fluorescence, thermography and electrical activity has been elaborated for cardiac surgery. The fluorescence imaging of nicotinamide adenine dinucleoticle NAD(P)H in the blue light range (lambda=467 nm) by using UV light (X=347 nm) excitation was used to detect metabolic disturbances. The method of the principal component analysis was used for the processing of the fluorescence image sequences. Far infrared (lambda=7.5-13 mu m) imaging was used to evaluate temperature dynamics of the tissue surface during circulation disturbances. Evaluation of the epicardial electrogram shape by using continuous wavelet transform was used to detect and evaluate ischemia-caused disturbances of the electrical activity of the tissue. The combination of temperature, fluorescence and electrical activity estimates obtained from synchronically registered parameters during the experiments on model systems and experimental animals yielded qualitatively new results for the evaluation of cardiac tissue viability and enabled to achieve a versatile evaluation of the heart tissue viabilityKauno medicinos universiteto Biomedicininių tyrimų institutasKauno medicinos universiteto Kardiologijos instituta

Širdies audinių temperatūros stebėsena ir nuosruvių funkcijos įvertinimas kardiochirurginių operacijų metu

Thermography is a relatively new contact-free method used in experimental and clinical studies and in cardiovascular surgery to investigate the myocardium and coronary artery function. Objects of complex study included mongrel dogs and patients with coronary artery disease who underwent cardiac surgery. For active dynamic thermography, we used a thermovision camera “A20V” (FLIR Systems, USA). Our data indicate that both experimental and clinical study performed on beating hearts could be an important approach to interoperation inspection of autovenous graft function. An infrared camera also can be successfully used to determine the extent of ischemic damage to the myocardium, heart, and blood vessels during surgery as a significant prognostic tool for evaluating outcome after cardiac operation