Post Operative PVC’s, When to Worry?
Definition
 PVC’s are premature ventricular contractions, also known as Ventricular
premature beats (VPBs) or Ventricular Premature Depolarization (VPDs).
 PVC’s are ectopic impulses originating from a focus distal to the His Purkinje
system.
 PVC’s are the most common ventricular arrhythmia with variable prognostic
importance.
Pathophysiology
 Enhanced Automaticity- new site of depolarization in non-nodal ventricular
tissue. Associated with electrolyte abnormalities, ischemia, or increased
catecholamines.
 Triggered Activity- early or late afterdepolarizations that can be associated with
electrolyte abnormalities, ischemia, or drug toxicity (digoxin, prolonged QT)
 Reentry- occurs with unidirectional block (slow conducting myocardium next to
normal conducting tissue). Occurs in the setting of damaged myocardium.
Causes
 Cardiac- Acute MI, Valvular disease (MVP), Cardiomyopathy (ischemia, dilated,
hypertrophic), Cardiac Contusion, LVH, CHF (EF<40%), and Tachycardia
(associated w/ high catecholamine state), Previous Cardiac Surgery, Congenital
Heart Disease (h/o tetrology of fallot)
 NonCardiac- electrolyte abnormalities (hypokalemia, hypomagnesemia,
hypercalcemia), medications (digoxin, TCA, amitriptyline, pseudophedrine,
flouoxetine), drugs (cocaine, amphetamines, caffeine, alcohol), stress response
(surgery, infection), anesthestics (sevoflurane, droperidol, ondansetron, etc…)
Evaluation
 Symptomatic- palpitations, skipped beat, dizziness
 Past Medical/Surgical History/Physical Exam- high risk patient identification as
well as possible identification of underlying causes (renal failure, acute MI, etc…)
 Frequency- greater then 10/hr, bigeminy, trigeminy
 Character- multifocal vs. unifocal
Work-Up- look for underlying/reversible causes
 EKG- evaluate for ischemia, prolonged QT
 Electrolyte Panel- chem. 10 as well as Ca and Mg
Treatment- only needed for symptomatic pt’s, high risk pt’s (CHF, cardiomyopathy or
previous MI and EF<40%), or frequent PVC’s
 Beta-Blockers- 1st line treatment
 Amniodarone, Sotalol
Bottom Line Worry If:
 Pt is high risk: previous MI, CHF, Cardiomyopathy w/ EF<40%
 PVCs are frequent >10/hr, mutifocal, or bigeminy/trigeminy
 If there is any evidence of Acute Ischemia, hemodynamic instability, or altered
mental status
References:
1. Curry T., Gaver R., & White R. Acquired Long QT syndrome and Anesthesia. Pediatric
Anesthesia. Feb 2006;16,471-478.
2. Clinical Significance and Treatment of VPBs. www.uptodate.com
3. Ventricular Premature Complexes. www.emedicine.com
Kim Howard-Quijano M.D. 9/17/2008