In this work deals about the efficient intracardial ECG analysis algorithm. The main focus was design an optimal detection method for intracardial signals based on essential intracardial measuring methods and basic principles of gathering and processing data from invasive catheters. Intracardial ECG analysis is further important step in heart behavior understanding, especially it’s electric manners. Detailed signal description generated in heart,together with heart function knowledge can provide us with an useful information about heart’s condition or it’s diseases. Designed detection methodis able to mark significant points in intracardial records, compute it‘s elemental parameters and important time intervals. Incurred algorithm was designed and tested on intracardial records provided by Cardiology Clinic of Hospital IKEM – Praha, and Electrophysiology Laboratory of Hospital Podlesi – Trinec.