Related Experiment Video
Updated: May 31, 2026
05:26
Postconditioning with Lactate-enriched Blood for Cardioprotection in ST-segment Elevation Myocardial Infarction
Published on: May 28, 2019
Reconstituted high-density lipoprotein shortens cardiac repolarization.
Hester M Den Ruijter1, Remco Franssen, Arie O Verkerk
1Heart Failure Research Center, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam, the Netherlands.
Journal of the American College of Cardiology
|June 25, 2011
Summary
Increasing high-density lipoprotein cholesterol (HDL-C) shortens cardiac repolarization. This finding suggests a new mechanism by which HDL infusion may reduce sudden cardiac death risk.
Area of Science:
- Cardiovascular Science
- Lipid Metabolism
- Electrophysiology
Background:
- High-density lipoprotein cholesterol (HDL-C) is inversely associated with sudden cardiac death.
- The direct relationship between HDL-C levels and cardiac repolarization remains largely unexplored.
Purpose of the Study:
- To investigate the hypothesis that elevated HDL-C shortens cardiac repolarization.
- To explore a potential novel mechanism linking HDL to cardiac electrical stability.
Main Methods:
- Cardiac repolarization was assessed using the patch clamp technique on isolated rabbit cardiomyocytes exposed to reconstituted HDL (rHDL).
- Surface electrocardiograms (ECG) were recorded in dyslipidemic patients and healthy volunteers before and after rHDL infusion (40 mg/kg).
Main Results:
- rHDL and purified apolipoprotein AI significantly shortened repolarization in isolated cardiomyocytes by approximately 25%.
- rHDL infusion led to a significant shortening of the heart rate-corrected QT interval in all human participants.
Conclusions:
- Reconstituted HDL effectively shortens cardiac repolarization.
- These findings provide evidence for a novel mechanism through which HDL infusion may reduce the risk of sudden cardiac death.
Related Concept Videos
01:30Cardiac Action Potential
Cardiac action potentials are essential for proper heart function, enabling the rhythmic contractions needed for adequate blood circulation. Nodal cells and Purkinje fibers, specialized for electrical conduction, generate these action potentials.
The cardiac action potential process involves a series of phases characterized by the movement of ions across the cardiac cell membranes, leading to the depolarization and repolarization of the cardiac myocytes.
Ionic Basis of Cardiac Action Potentials
The cardiac action potential process involves a series of phases characterized by the movement of ions across the cardiac cell membranes, leading to the depolarization and repolarization of the cardiac myocytes.
Ionic Basis of Cardiac Action Potentials
01:20Antiarrhythmic Drugs: Class IV Agents as Calcium Channel Blockers
Class IV antiarrhythmic drugs, such as verapamil and diltiazem, block calcium channels. They primarily affect the heart, slowing the conduction in calcium-dependent tissues like the SA and AV nodes. These drugs manage reentrant supraventricular tachycardia (SVT) and reduce ventricular rate in atrial flutter/fibrillation.
Verapamil, a calcium channel blocker, inhibits calcium movement across myocardial cell membranes and vascular smooth muscle. This results in the dilation of coronary and...
Verapamil, a calcium channel blocker, inhibits calcium movement across myocardial cell membranes and vascular smooth muscle. This results in the dilation of coronary and...