Myocardial ischaemia and infarction in intraventricular conduction malfunctions on ECG

Czech version

Authors: D. Pospíšil; M. Sepši; M. Kozák
Authors‘ workplace: Interní kardiologická klinika LF MU a FN Brno
Published in: Kardiol Rev Int Med 2017, 19(4): 251-260

Overview

Malfunction of the electrical conduction system of the heart can make it difficult or impossible to recognise ischaemia or myocardial infarction. The most problematic ones are left intraventricular blocks, e.g. left bundle branch block or left anterior hemiblock, which disallow the development of pathological Q wave. If the conduction block is secondary to acute ischaemia, we call it an acquired block, which is associated with massive muscle damage. On the other hand, pre-existing blocks do not affect the prognosis, although they are quite frequent. It is important to monitor the patient’s clinical and laboratory status and to assess ST-T changes over time. Acute ischaemia can also be imitated or masked by the existence of an accessory pathway with prograde conduction or by ventricular pacing with an implantable device.

Key words:
electrocardiogram – ECG – heart conduction system – bundle branch block, ischaemia, myocardial infarction

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