Risk of LVEF decline and CHF associated with dual HER2 blockade
All of the 15 included trials reported the LVEF decline data, thus included for calculating the OR of LVEF decline associated with dual HER2 blockade. A total of 284 LVEF decline events were observed in dual HER2 blockade versus 357 LVEF decline events in anti-HER2 monotherapy. The pooled results demonstrated that the dual HER-2 blockade in cancer patients significantly increased the risk of developing LVEF decline with an OR of 1.20 (95% CI 1.02–1.41, p =0.031, Figure 3A) using a fixed-effects model (χ2-based Q statistic test: Q=22.58;p =0.091, I 2 =32.6).
A total of 14 randomized trials reported CHF data. A total of 55 CHF events were observed in dual HER2 blockade versus 57 CHF events in anti-HER2 monotherapy. The pooled results showed that the dual HER-2 blockade in cancer patients significantly increased risk of developing CHF with an OR of 1.45 (95% CI 1.00–2.11, p =0.049, Figure 3B) using a fixed-effects model (χ2-based Q statistic test: Q=12.67;p =0.53, I 2 =0).