Introduction
- Cause : usually myocardial irritation due to primary cardiac or systemic disease.
- Signs : depends on frequency - may be asymptomatic or weakness and lethargy.
- Diagnosis : electrocardiography.
- Treatment : treat underlying disease, antidysrhythmic agents if required.
- Prognosis : variable - occasional VPCs do not effect mortality. Guarded related to significant underlying pathology.
Diagnosis
Clinical signs
- Irregular heart beat.
- VPCs may be linked to normal beat so may regularly hear irregular sounds, ie double beat followed by compensatory pause.
- Pulse rate does not match heart rate (pulse deficit).
- Evidence of poor peripheral perfusion, eg pallor.
- Signs of underlying disease, eg murmur.
Diagnosis
Differential diagnosis
- Atrial premature contraction with abnormal ventricular conduction.
- Bundle branch block.
- Ventricular escape complexes.
Sequelae
Prognosis
- Depends on underlying disease - if this can be controlled dysrhythmia may resolve spontaneously.
- Electrically unstable VPCs may progress to ventricular tachycardia which carries a guarded prognosis.
Expected response to treatment
- Reduced frequency of VPCs on electrocardiogram.
- Improving demeanor of patient.
Reasons for treatment failure
- Severe underlying pathology.
- Failure to recognize and treat progressing VPCs before ventricular tachycardia
develops.
