What is Vectorcardiography

In order to diagnose a possible cardiac disorder, ECG (electrocardiogram) signals are usually recorded on standard grid papers in hospitals. Many efforts have been made to advance the technology in order to improve the diagnosis and management of cardiovascular disease. There is a need to convert the existing ECG records into digital forms, as it is the most efficient method to store and analyze ECG attributes for clinical uses. The main purpose of this chapter is to review the existing algorithms for digital conversion of paper ECG. It discusses the various challenges and a systematic study on different methods that have been used so far to convert paper ECG records into digitized form so that they can be retrieved efficiently. Initial challenge involved in the digitization process is gridline removal. In this process, information of ECG signal is also removed. None of the existing methods provide flawless gridline removal. The paper ECG used in hospitals differs in shape, size, formats, so the main challenge in digitization process is to achieve a worldwide ECG format.