CBS 2019
CBSMD教育中心
中 文

充血性心力衰竭

Abstract

Recommended Article

The prevalence and importance of frailty in heart failure with reduced ejection fraction - an analysis of PARADIGM-HF and ATMOSPHERE Dilated cardiomyopathy: so many cardiomyopathies! Lateral Wall Dysfunction Signals Onset of Progressive Heart Failure in Left Bundle Branch Block Metformin Lowers Body Weight But Fails to Increase Insulin Sensitivity in Chronic Heart Failure Patients without Diabetes: a Randomized, Double-Blind, Placebo-Controlled Study Longitudinal Change in Galectin-3 and Incident Cardiovascular Outcomes Cardiac resynchronization therapy with a defibrillator (CRTd) in failing heart patients with type 2 diabetes mellitus and treated by glucagon-like peptide 1 receptor agonists (GLP-1 RA) therapy vs. conventional hypoglycemic drugs: arrhythmic burden, hospitalizations for heart failure, and CRTd responders rate Exercise Intolerance in Patients With Heart Failure: JACC State-of-the-Art Review Heart Failure With Recovered Left Ventricular Ejection Fraction: JACC Scientific Expert Panel

Original Research2020 Aug 3;258:120285.

JOURNAL:Biomaterials. Article Link

The conductive function of biopolymer corrects myocardial scar conduction blockage and resynchronizes contraction to prevent heart failure

S He, J Wu, RK Li et al. Keywords: conductive biomaterial; HF; myocardial infarction; resynchronization.

ABSTRACT

Myocardial fibrosis, resulting from ischemic injury, increases tissue resistivity in the infarct area, which impedes heart synchronous electrical propagation. The uneven conduction between myocardium and fibrotic tissue leads to dys-synchronous contraction, which progresses towards ventricular dysfunction. We synthesized a conductive poly-pyrrole-chitosan hydrogel (PPY-CHI), and investigated its capabilities in improving electrical propagation in fibrotic tissue, as well as resynchronizing cardiac contraction to preserve cardiac function. In an in vitro fibrotic scar model, conductivity increased in proportion to the amount of PPY-CHI hydrogel added. To elucidate the mechanism of interaction between myocardial ionic changes and electrical current, an equivalent circuit model was used, which showed that PPY-CHI resistance was 10 times lower, and latency time 5 times shorter, compared to controls. Using a rat myocardial infarction (MI) model, PPY-CHI was injected into fibrotic tissue 7 days post MI. There, PPY-CHI reduced tissue resistance by 30%, improved electrical conduction across the fibrotic scar by 33%, enhanced field potential amplitudes by 2 times, and resynchronized cardiac contraction. PPY-CHI hydrogel also preserved cardiac function at 3 months, and reduced susceptibility to arrhythmia by 30% post-MI. These data demonstrated that the conductive PPY-CHI hydrogel reduced fibrotic scar resistivity, and enhanced electrical conduction, to synchronize cardiac contraction.