Ventricular arrhythmias occur commonly in clinical practice and range from benign asymptomatic premature ventricular complexes (PVCs) to ventricular fibrillation (VF) resulting in sudden death. The presence of structural heart disease plays a major role in risk stratification; however, it is important to recognize potentially lethal arrhythmias that may occur in structurally normal-appearing hearts. In general, management depends on the associated symptoms, hemodynamic consequences, and associated long-term prognosis. Initial management, risk stratification, and treatment of ventricular arrhythmias pose a significant challenge to clinicians. This chapter provides an overview of the clinical presentation, natural history, diagnosis, and therapeutic options for the ventricular arrhythmias encountered in clinical practice.
Care has been taken to incorporate the American College of Cardiology/American Heart Association/European Society of Cardiology (ACC/AHA/ESC) 2006 Guidelines for Management of Patients With Ventricular Arrhythmias and the Prevention of Sudden Cardiac Death and the ACC/AHA/Heart Rhythm Society (HRS) 2008 Guidelines for Device-Based Therapy of Cardiac Rhythm Abnormalities.1,2 As with all ACC/AHA guidelines, these documents provide specific categories of recommendation, according to the level of evidence available (Table 42–1).
Table 42–1. Classification of Recommendations and Levels of Evidence to Support Them |Favorite Table|Download (.pdf)
Table 42–1. Classification of Recommendations and Levels of Evidence to Support Them
|Classification of recommendations|
- Class I: Conditions for which there is evidence and/or general agreement that a given procedure or treatment is beneficial, useful, and effective.
- Class II: Conditions for which there is conflicting evidence and/or divergence of opinion about the usefulness/efficacy of a procedure or treatment.
- Class IIa: Weight of evidence/opinion is in favor of usefulness/efficacy.
- Class IIb: Usefulness/efficacy is less established by evidence/opinion.
- Class III: Conditions for which there is evidence and/or general agreement that a procedure/treatment is not useful/effective and in some cases may be harmful.
|Level of evidence|
- Level of Evidence A: Data derived from multiple randomized clinical trials or meta-analyses.
- Level of Evidence B: Data derived from a single randomized trial or nonrandomized studies.
- Level of Evidence C: Only consensus opinion of experts, case studies, or standard of care.
PVCs are commonly seen in clinical practice. The significance of PVCs depends on the frequency of PVCs, the presence and severity of structural heart disease, and the presence of associated symptoms.
PVCs in the Absence of Organic Heart Disease
PVCs occur frequently in the general population.3 In general, PVCs that occur in patients without structural heart disease are not associated with excess risk of sudden death. Kennedy and coworkers4 studied 73 patients with frequent ventricular ectopy and no structural heart disease on a 24-hour ambulatory (Holter) monitor. Patients were followed for an average of 6.5 years with no excess in mortality. PVCs that occur in patients with a structurally normal heart warrant no therapy, unless significant symptoms are present.
PVCs after Myocardial Infarction