Predictors of echocardiographic response in the Budapest-CRT upgrade trial - Eperke Merkel; Richárd Masszi; Bálint Lakatos; Robert Hatala; Boglárka Veres; Alexandra Fábián; István Osztheimer; László Gellér; Tamás Urbán; Csaba Horváth; Scott D. Solomon; Valentina Kutyifa; et al. (Clinical Research in Cardiology, 2026)