[ECG] VPCs, VPBs, PVBs

Treatment of ventricular premature beats
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General principles —
Two issues need to be addressed in the patient found to have VPBs. The first relates to the possible presence of underlying structural heart disease, which has prognostic significance and may require specific therapy which, in some cases, may also reduce VPBs.
The two major examples are beta blockers, which improve survival in patients with a prior myocardial infarction or heart failure, and antihypertensive therapy to induce regression of LVH in patients with hypertension [23].
The second issue relates to whether the VPBs produce symptoms. As noted in the preceding discussions, there is no clear evidence that VPBs alone are an independent risk factor for mortality or that VPB suppression with antiarrhythmic drugs improves overall survival in patients who have not had a major arrhythmic event. Thus, the only indication for the use of antiarrhythmic drugs for VPB suppression is in symptomatic patients. In addition to symptoms related to ectopy, frequent VPBs can result in deterioration of left ventricular function in patients with left ventricular dysfunction [21].
Limited role for antiarrhythmic drugs — In addition to the lack of benefit from VPB suppression in asymptomatic patients, some antiarrhythmic drugs (eg, flecainide, encainide, and d-sotalol) are associated with increased mortality due to proarrhythmia, primarily when given to patients with a prior MI. Proarrhythmia is less of a concern in patients without organic heart disease [35].
When an antiarrhythmic drug is given to suppress symptomatic VPBs, the drugs of choice are a beta blocker and amiodarone, both of which are effective and have no or little potential for proarrhythmia(促心律不整性), respectively. Sotalol is an alternative agent [36]. Furthermore, among patients with a prior MI or heart failure, a beta blocker should be part of standard therapy because of a clear survival benefit. This benefit may be associated with a reduction in VPBs.
Beta blockers are the first-line drugs for suppression of symptomatic VPBs. The lowest dose of beta blockers that relieves symptoms should be used in order to minimize side effects with the exception of patients with a prior MI or heart failure in whom the dose is titrated to that recommended for treatment of the underlying disease.
Amiodarone can be added in patients who remain symptomatic or who cannot tolerate beta blockers.(先用BB不行再用Amiodarone) Trials of amiodarone use in patients with VPBs post-MI (eg, CAMIAT and EMIAT) or with VPBs and heart failure (eg, CHF-STAT) have demonstrated a significant reduction in VPBs and in arrhythmic mortality, but routine amiodarone therapy is not recommended in asymptomatic patients because of the absence of a significant improvement in overall mortality. Subset analysis has suggested that overall mortality in post-MI patients may be significantly reduced when amiodarone is given to patients also treated with a beta blocker. These issues are discussed in detail separately.
Sotalol, dofetilide and, when available, azimilide do not appear to be harmful in patients who have had an MI. Although only limited data are available concerning the efficacy of these drugs for VPBs, they may be considered in patients who do not tolerate or respond to amiodarone.
Other therapies — Some alternative techniques that have been employed for VPB suppression include biofeedback, exercise, anxiolytics, and stress reduction. Whether these measures have a significant effect on the majority of patients, and if so, how much is a placebo effect, is not known. In addition, anxiolytics have the potential induce psychologic and physical dependence.
Frequent VPBs may be associated with worsening of systolic heart failure in patients with a dilated cardiomyopathy. Small studies have suggested that in selected patients, radiofrequency ablation of ectopic ventricular foci is associated with an improvement in left ventricular function and clinical improvement in symptoms [1,2,47,48].
The 2006 American College of Cardiology/American Heart Association/European Society of Cardiology (ACC/AHA/ESC) guidelines for the management of ventricular arrhythmias included suggestions regarding ablation therapy for VPBs [49]. They note that ablation of VPBs may be useful in the following settings:
• VPBs that are frequent, symptomatic, and monomorphic, if they are refractory to medical therapy or if the patient chooses to avoid long-term medical therapy.
Ventricular arrhythmia storm that is consistently provoked by VPBs of a similar morphology [50].