[Diagnostic significance of QRST isointegral map in patients with premature ventricular contraction]

Identification of the focus of premature ventricular contraction (PVC) has been reported by various body surface mapping methods: i.e. PVC isopotential map, ventricular activation time map, QRS isointegral map, PVC T wave map, etc. For evaluating the clinical usefulness and diagnostic significance of QRST isointegral map in patients with PVC, 23 patients without apparent underlying heart disease (group N), and 44 patients with dilated cardiomyopathy (group D), were studied. The significant changes in QRST values at maximal points during two activation sequences (basic rhythm and PVC) were detected in group D (N:D = 26.6 +/- 17.6:52.6 +/- 27.0%, p < 0.01), which were frequently directed to the PVC focus and influenced by the short coupling interval (Q-Q interval: 300-390 ms). In conclusion, QRST isointegral map reflecting ventricular gradient may be useful for identifying the presence of underlying heart disease and may correlate with the focus and coupling interval of PVC.