Cirrhotic Cardiomyopathy Following Bile Duct Ligation in Rats—A Matter of Time?

Cirrhotic patients often suffer from cirrhotic cardiomyopathy (CCM). Previous animal models of CCM were inconsistent concerning the time and mechanism of injury; thus, the temporal dynamics and cardiac vulnerability were studied in more detail. Rats underwent bile duct ligation (BDL) and a second surgery 28 days later. Cardiac function was assessed by conductance catheter and echocardiography. Histology, gene expression, and serum parameters were analyzed. A chronotropic incompetence (P(d31) < 0.001) and impaired contractility at rest and a reduced contractile reserve (P(d31) = 0.03, P(dob-d31) < 0.001) were seen 31 days after BDL with increased creatine (P(d35), P(d42), and P(d56) < 0.05) and transaminases (P(d31) < 0.001). A total of 56 days after BDL, myocardial fibrosis was seen (P(d56) < 0.001) accompanied by macrophage infiltration (CD68: P(group) < 0.001) and systemic inflammation (TNFα: P(group) < 0.001, white blood cell count: P(group) < 0.001). Myocardial expression of peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC1α) was increased after 31 (P(d31) < 0.001) and decreased after 42 (P(d42) < 0.001) and 56 days (P(d56) < 0.001). Caspase-3 expression was increased 31 and 56 days after BDL (P(d31) = 0.005; P(d56) = 0.005). Structural changes in the myocardium were seen after 8 weeks. After the second surgery (second hit), transient myocardial insufficiency with secondary organ dysfunction was seen, characterized by reduced contractility and contractile reserve.