Cirrhotic cardiomyopathy

Potential mechanisms involved in the impaired contractile function of the cardiomyocyte in cirrhotic cardiomyopathy: Down-regulation of β-adrenergic receptors with decreased content of G-protein (G_αi: inhibitory G-protein; G_αs: stimulatory G-protein); up-regulation of cannabinoid 1-receptor stimulation; increased inhibitory effects of cardiodepressant substances such as haemoxygenase (HO), carbon monoxide (CO), nitric oxide synthase (NOS)-induced nitric oxide (NO) release, and tumour necrosis factor-α (TNF-α). Many post-receptor effects are mediated by adenylcyclase (AC) inhibition or stimulation. (RGS: regulator of G-protein signalling; PDE: phosphodiesterase; PKA: protein kinase A). Sarcoplasmatic reticulum (SR), Altered function and reduced conductance of potassium channels, inhibition of L-type calcium channels, and increased fluidity of the plasma membrane (increased cholesterol/phospholipid ratio) also contribute to reduced calcium release and contractility together with altered ratio of collagens and titins.

Brain natriuretic peptide (BNP) and its pro-peptide (pro-BNP) in controls and in patients with cirrhosis, according to the Child–Turcotte classification. BNP and pro-BNP are significantly increased in cirrhosis and correlate with the prolonged QT interval, indicating that the cardiac generation of BNPs reflects cardiac dysfunction in cirrhosis. Data from Henriksen et al. [73].

Schematic illustration of the transmitral Doppler flow profile. Peak E denotes the early filling of the ventricle and peak A the late atrial contribution. Diastolic dysfunction induces characteristic changes in the flow pattern, including increased E/A ratio and prolonged deceleration time (DT). The lower diagrams show a normal filling pattern (left) and a filling pattern indicating diastolic dysfunction (right).

Mechanical and electrical time intervals from the aortic pressure curve and electrocardiogram. (A) P_a, arterial pressure as a function of time; t_P, time to peak pressure; t_S, systolic time; t_D, diastolic time; t_RR, time of one heart cycle; QT interval, the time from the start of the Q wave to the end of the T wave. (B) Difference between electrical and mechanical systole time (Δt=QT−t_S) in controls and patients with cirrhosis. Data from Henriksen et al. [113].

Illustration of reversibility of systolic dysfunction in patients with cirrhosis and controls. The change in heart rate (dHR), cardiac index (dCI), and left-ventricular ejection fraction (dEF) after stress ventriculography significantly improved following liver transplantation (Ltx). ^∗p<0.05. ^∗∗p<0.01. Figure based on data from Torregrosa et al. [12].