Early reperfusion is the best therapy for myocardial infarction (MI). Effectiveness, however, varies significantly between patients and has implications for long-term prognosis and treatment. A technique to assess the extent of myocardial salvage after reperfusion therapy would allow for high-risk patients to be identified in the early post-MI period. Mitochondrial dysfunction is associated with cell death following myocardial reperfusion and can be quantified by fluorometry. Therefore, we hypothesized that variations in the fluorescence of mitochondrial nicotinamide adenine dinucleotide (NADH) and flavoprotein (FP) can be used acutely to predict the degree of myocardial injury. Thirteen rabbits had coronary occlusion for 30 min followed by 3 h of reperfusion. To produce a spectrum of infarct sizes, six animals were infused cyclosporine A prior to ischemia. Using a specially designed fluorometric probe, NADH and FP fluorescence were measured in the ischemic area. Changes in NADH and FP fluorescence, as early as 15 min after reperfusion, correlated with postmortem assessment infarct size (r=0.695, p<0.01). This correlation strengthened with time (r=0.827, p<0.01 after 180 min). Clinical application of catheter-based myocardial fluorometry may provide a minimally invasive technique for assessing the early response to reperfusion therapy.
Date of this Version
bio-optics, biomedical measurement, cardiology, cellular biophysics, diseases, fluorescence, muscle, patient treatment, acute myocardial injury, cell death, cyclosporine A, flavoprotein, fluorescence, ischemia, mitochondrial dysfunction, myocardial infarction, myocardial salvage, nicotinamide adenine dinucleotide, ratiometric fluorometry, reperfusion therapy, time 3 h, time 30 min, Apoptosis, fluorometery, mitochondrial disruption, mitochondrial redox state, myocardial infarction, myocardial reperfusion injury
Date Posted: 13 October 2009
This document has been peer reviewed.