CBS 2019
CBSMD教育中心
中 文

Congestive Heart Failure

Abstract

Recommended Article

AIM2-driven inflammasome activation in heart failure Natriuretic Peptide-Guided Heart Failure Therapy After the GUIDE-IT Study Progression of Device-Detected Subclinical Atrial Fibrillation and the Risk of Heart Failure Positive recommendation for angiotensin receptor/neprilysin inhibitor: First medication approval for heart failure without "reduced ejection fraction" Cardiovascular Aging and Heart Failure: JACC Review Topic of the Week Dapagliflozin in Patients with Heart Failure and Reduced Ejection Fraction Longitudinal Change in Galectin-3 and Incident Cardiovascular Outcomes Seattle Heart Failure and Proportional Risk Models Predict Benefit From Implantable Cardioverter-Defibrillators

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.