52 years old male with palpitations and dyspnea.

1. The first ECG finding of this ECG Case is non standard voltage calibration. Instead of 10mm/1mv, voltage calibration is done 5mm/1mv. Half standard calibration was used to prevent superposition of waveforms.

            At the beginning of the ECG recording, the ECG machine automatically performs a calibration while recording a rectangular shape signal with different amplitude.

Fig.1.The calibration signal (marked with red) has 5mm vertically. This show presence of half standard calibration (5mm/1mv), instead of 10mm/mV.

2. Basic normocardic sinus rhythm is interfered from a Ventricular Extrasystole (QRS nr. 4). This complex fulfills all criteria for Ventricular Extrasystole: QRS is wider than 0.12 s, is premature, followed by a compensatory pause and discordant ST.

              From QTS complex nr.7, begins a regular uniform wide complex tachycardia and continues until end of rhythm strips (QRS nr.24). Rhythm from 7-24 represents an episode of Monomorphic Ventricular Tachycardia with frequency ~180/min. Ventricular exstrasystole and Ventricular tachycardia have same morphology showing unifocal origin. 

Fig.2. VES (nr. 4) and VT (7-24) are marked with red.

3. Third significant finding is abnormal left axis deviation caused my Left Anterior Hemi Block (LAHB). qR pattern in I and aVL plus rS in II and III is quite enough to diagnose LAHB.

Fig.3. qr pattern in I and aVL plus rS in II and III (marked with red) in patient with abnormal left axis deviation diagnose LAHB.

Final diagnosis: Sinus rhythm. Monomorphic Ventricular Tachycardia. LAHB. Non standart voltage calibration.