Heart rate variability is an important tool for cardiac diagnosis. In this work, the band analysis of Very Low Frequency (VLF) is performed using Wavelet Packet Transform (WPT) on VTA (Ventricular Tachyarrhythmia) Patients. In order to determine the performance of Daubechies Wavelets, the energy value of each nodes is computed using db4, db8, db12, db16 and db20 WPTs. The energy characteristic of main VLF band is estimated from sub-bands using Multilayer Perceptron Neural Network and dominant sub-bands of VLF are obtained. The dominant band is determined and the performance of Daubechies Wavelets is compared in VLF band.