Introduction
Extrasystole, or premature ventricular extrasystole (PVC), is caused by an ectopic pacemaker in the ventricles.
They appear as wide QRS complexes, not preceded by P waves.
The typical pattern for these PVCs is a tall R wave, with inverted T waves with LBBB or RBBB morphology. These are usually asymptomatic, but for symptomatic individuals, beta-blockers are the first-line treatment.
Clinical Presentation:
History is an important first step to distinguish symptomatic PVCs from asymptomatic ones. Symptomatic patients may suggest underlying ischemic heart disease (IHD), such as angina, chest pain, or hemodynamic compromise.
In history, the patient may report:
– Feeling of the heart stopping
– Lightheadedness
– Syncope (as frequent PVCs can cause hypotension)
On Examination (O/E):
– Hemodynamic compromise in symptomatic patients
– Neurologic examination may indicate sympathetic activation, suggesting catecholamines as the cause of ectopy
– Cardiac findings may show a Cannon A wave at the time of PVC
Investigations:
1. ECG: To confirm the presence of PVCs and identify the underlying cause
2. ECHO: To assess cardiac structure and function
3. Laboratory tests: For drug levels and serum electrolytes
Emergency Management:
Outpatient or emergency management depends on whether the individual is symptomatic.
For ED Management:
Non-invasive measures:
– Treat hypoxia
– Correct any drug toxicity
– Correct electrolyte imbalances
If acute MI is the cause:
– Use beta-blockers for hemodynamically stable patients
Invasive measures:
– Catheter ablation