Concertina effect in WPW syndrome is varying QRS width in WPW syndrome due to varying degrees of pre-excitation. More the pre-excitation, shorter the PR and wider the QRS.
ECG features suggesting epicardial ablation of VT: Pseudo delta, Intrinsicoid deflection 85 ms or more, R/S complex 121 ms or more, Q waves in lead I and no
Global ischemic contracture of the heart resulting in a firm myocardium and loss of intracavitary volume is termed stone heart syndrome. It was described in the early years
Ventricular tachycardia can be treated with intravenous amiodarone or lignocaine. In case of hemodynamic compromise, electrical cardioversion with a direct current shock is needed.
Magnesium blocks the L-type calcium channels and suppresses early afterdepolarizations (EAD) to subthreshold amplitude and hence reduces the chance of torsade de pointes.
Isolated hypomagnesemia is rare and has been reported to cause global T wave inversion. Most of the arrhythmias associated with hypomagnesemia has hypokalemia as contributing factor. Suppression of
ST segment prolongation without changes in the T wave is the hallmark of hypocalcemia. ECG changes and clinical features of hypocalcemia are due to lowering of ionized calcium
