After myocardial infarction, regional damage of autonomic sympathetic innervation is often more extensive than of myocard itself. This difference is called Tl-MIBG-Mismatch and quantifies the amount of sympathetic denervated but viable myocardium. Results of animal studies point out that the electrophysiologic mecanisms of this myocardium are disordered. It remains unclear, wheather this kind of denervation causes changes in surface-ECG. In this study we prospectively evaluated wheather ECG-parameters korrelate to Tl-MIBG-Mismatch. 67 patients after acute myocardial infarction were included in this study. Within 14 days after reperfusion therapy, scintigraphic imaging was done with I-123-MIBG for visualisation of autonomic sympathetic denervation and with Cl-210-Thallium for visualisation of viable myocardium. The scintigraphic images of tracer-distribution were transformed to a "polar map" with 460 pixels. The sum of pixels with tracer-activities below 50% of maximal activity quantified distribution defect. The difference of neuronal and myocardial defect-size equals Tl-MIBG-mismatch, which was compared to parameters of resting-ECG, signal-averaged-ECG and Holter-ECG. Of many patients the neuronal defect was greater than the myocardial defect (38.4±22.2% vs. 14.3±16.4%), resulting in an average denervation of 25.8±16.3% of viable myocardium. Only two parameters korrelated significantly with Tl-MIBG-Mismatch: an inverse korrelation was shown for RMS40 of signal-averaged-ECG (r=–0.37, p=0.0053), indicating a relative slow conduction in the denervated myocardium. A positive korrelation was shown for QTc (frequency-corrected QT-time of resting-ECG) (r=0.34, p=0.0064), indicating a relative slow repolarisation in the denervated myocardium. These findings might be indicative for relatively slow depolarisation and repolarisation processes in denervated but viable myocardium.     «

After myocardial infarction, regional damage of autonomic sympathetic innervation is often more extensive than of myocard itself. This difference is called Tl-MIBG-Mismatch and quantifies the amount of sympathetic denervated but viable myocardium. Results of animal studies point out that the electrophysiologic mecanisms of this myocardium are disordered. It remains unclear, wheather this kind of denervation causes changes in surface-ECG. In this study we prospectively evaluated wheather ECG-para...     »