Study Selection

The criteria about literature inclusion are as follows: 1) Study design: RCTs. 2) Participants: All the enrolled participants were required to meet the current or past definitions of HF and VA. Trials without a description of the detailed diagnostic criteria but which reported patients with definite HF-VA were also included. 3) Interventions: The control group was treated with amiodarone alone. While, the experimental group was treated with SSYX and amiodarone. The basic therapies in two groups were similar, including angiote nsin II receptor antagonists, angiotensin-converting enzyme inhibitors, beta-blockers, diuretics, aldosterone receptor antagonists, nitrates, et al. SSYX was the only intervention difference between the control group and the experimental group in all studies. 4) Outcomes: The primary outcomes included the total effective rate and ADRs. The secondary outcomes included the frequency of ventricular premature complexes (VPCs), left ventricular ejection fraction (LVEF), N terminal pro Btype natriuretic peptide (NT-proBNP), and QT dispersion (QTd). The included studies reported at least one of the above outcomes.

The criteria of literature exclusion were as follows: 1) For duplicate publications, only those with the earliest publication time were selected. 2) Interventions in the control group included other traditional Chinese medicine therapies, such as acupuncture or Chinese herbs. 3) The criteria of efficiency evaluation did not meet the following definitions: Markedly effective: Based on 24 h electrocardiogram, VPCs disappeared or decreased by 70% or more; Ventricular tachycardias (VTs) disappeared or decreased by 80% or more; The improvement of New York Heart Association functional class (NYHA) was more than two grades or reached grade I, and there was an obvious improvement in the clinical symptom. Effective: VPCs decreased by 50–70%; VTs decreased by 50–80%; The improvement of NYHA was more than one grade or reached grade I, and the clinical symptom partially improved partly. Ineffective: It did not reach the above standards of efficiency, and even exacerbation. The total effective rate = markedly effective rate + effective rate.