Efficacy and safety of Kuoxin Formula in the treatment of dilated cardiomyopathy-related heart failure (Qi-Yin deficiency combined with blood stasis syndrome): study protocol of a randomized, double-blind, placebo-controlled, multi-center clinical trial

Background Dilated cardiomyopathy (DCM) is a severe condition characterized by cardiac enlargement and declining heart function, often leading to refractory heart failure and life-threatening outcomes. Globally, and particularly in China, a notable challenge arises from the insufficient availability of targeted therapies demonstrating significant efficacy for DCM. Additionally, the application of traditional anti-heart failure drugs in DCM is constrained, as many patients exhibit a propensity for hypotension or show limited improvement in their heart failure symptoms. Kuoxin Formula (KXF), an internally agreed-upon prescription at Longhua Hospital, is supported by clear biological evidence for improving cardiac function and myocardial remodeling. Previous clinical studies have also demonstrated its potential to improve patients' quality of life. This trial aims to further evaluate the safety and efficacy of KXF in treating DCM -related heart failure. Method This prospective, randomized, double-blind, placebo-controlled, multicenter trial recruits 230 patients diagnosed with DCM (Qi-Yin deficiency combined with blood stasis syndrome) from five centers. Participants will be randomly assigned in a 1:1 ratio to either the KXF treatment group or a placebo group. The treatment will span 12 weeks, during which key indicators and adverse events will be monitored. The primary outcome is the proportion of patients whose NT-proBNP decreased by more than 30%. The secondary outcomes include the NYHA functional classification, TCM syndrome scores, echocardiographic parameters, TGF-β, PICP, CITP, galectin-3, ST2 levels, 6MWT, Lee's heart failure score, and MLHFQ score. Discussion: This study will be the first multicentered research conducted in China that utilizes a randomized, double-blind, placebo-controlled design to investigate the use of TCM in the treatment of dilated cardiomyopathy. It seeks to develop new theoretical frameworks and provide solid clinical data to support the integration of TCM and modern medicine in treating heart failure in DCM patients. Trial Registration: China Clinical Trial Registry, ChiCTR2300068937. Registered on March 1, 2023.