The CardioExpress SL18A 18-lead ECG obtains right side chest leads (V3R, V4R and V5R) and posterior leads (V7, V8 and V9) at the same time, which offers more evidence in certain cases e.g. PMI and RVI compared to traditional 12-lead ECG devices. It also highlights the arrhythmia part of an ECG waveform with a conspicuous color that enables the user to identify arrhythmias consistently.