Exercise high resolution ECG in patients with hypertrophic cardiomyopathy: preliminary study

The exercise high resolution ECG (EHRECG) study was performed in two groups: 13 healthy individuals (normals) and 24 patients with hypertrophic cardiomyopathy (HCM). The standard HRECG parameters for both groups were similar(QRSdur: 107+/-7 vs 114+/-18ms, n.s). The EHRECG signal was acquired in rest, then in peak exercise (-30 beats) for further shea time signal averaging (STSA) as well as for adaptive filtering process (AFP) to extract an exercise component. The exercise was done in supine position on a bicycle ergometer. The load of SOW was incremented by 50W steps in 3min intervals and test was terminated by fatigue. Signals were recorded in XYZ bipolar leads with 20Hz high pass filter. The STSA revealed the QRS shortening of 2.4+/-2.5ms in 11 normals and prolongation of 3.2+/-2.9ms in 19 HCM patients. The exercise component obtained as the result of AFP revealed statistically significant difference between normals and HCM patients (64+/-4ms vs 71+/-6 ms, p<0.0024) and between HCM patients with and without VT/DS (74+/-6ms vs 69+/-6ms, p<0.046).