Amiodarone and β-blocker combination therapy versus β-blocker monotherapy for ICD shock prevention: A meta-analysis.

While implantable cardioverter-defibrillator (ICD) shocks are a lifesaving therapy, they can negatively affect the patient's quality of life. Amiodarone is commonly combined with β-blockers (BB) in ICD recipients. However, this combination therapy's efficacy in preventing shocks compared to standard BB monotherapy is not well studied. The aim of this systematic review and meta-analysis is to determine if combined amiodarone and BB therapy improves prevention of ICD shock delivery compared to BB monotherapy. We performed a comprehensive literature search using PubMed, Cochrane, and Web of Science databases, for studies that assess the impact of amiodarone and BB versus BB monotherapy in patients with an ICD. The primary outcome was a total number of ICD shocks delivered by the end of the study period. Four studies: three retrospective studies and one randomized controlled trial (RCT), with a total of 5818 patients with ICDs, were included in the analysis. Follow-up periods ranged from 1 to 5 years. The combined amiodarone and BB group was not associated with a significantly lower number of ICD shocks compared to the BB monotherapy group (OR, 0.76; 95% CI, 0.44-1.31; P = .32). A combination therapy of amiodarone and BB was not associated with any further reduction in ICD shocks, hospitalizations, or mortality. Additional RCTs are recommended to further validate our findings.