Related Experiment Video

Updated: Jun 22, 2026

Implantation of Electroencephalogram and Electrocardiogram Telemetry Devices in Neonatal Rabbit Kits
06:46

Implantation of Electroencephalogram and Electrocardiogram Telemetry Devices in Neonatal Rabbit Kits

Published on: February 28, 2025

Hyperhomocysteinemia and sudden cardiac death: potential arrhythmogenic mechanisms

Claudio Maldonado1, Chirag V Soni, Nathan D Todnem

  • 1Department of Physiology and Biophysics, and Department of Surgery, University of Louisville, Louisville, KY 40292, USA. cjmald01@louisville.edu

Current Vascular Pharmacology
|June 3, 2009
PubMed

Insights

Elevated homocysteine (Hcy) causes heart rhythm problems and sudden cardiac death by affecting cardiac cells and conduction. B vitamin supplements may help patients with hyperhomocysteinemia and heart disease.

Area of Science:

  • Cardiology
  • Biochemistry
  • Pathophysiology

Background:

  • Elevated serum homocysteine (Hcy) causes hyperhomocysteinemia (HHcy), linked to cardiac diseases like coronary heart disease (CHD), arrhythmias, and sudden cardiac death (SCD).
  • Mechanisms linking HHcy to cardiac arrhythmias and SCD remain unclear.
  • Hcy acts as an N-methyl-D-aspartate receptor (NMDA-R) agonist in cardiac tissue, increasing intracellular calcium and cell excitability.

Purpose of the Study:

  • To review literature on HHcy-induced cardiac tissue remodeling.
  • To explore mechanisms of HHcy-induced arrhythmogenesis and SCD.
  • To evaluate B vitamin supplementation efficacy in HHcy and CHD patients.

Main Methods:

  • Literature review focusing on HHcy, cardiac pathology, and oxidative stress.
  • Analysis of studies investigating Hcy's role as an NMDA-R agonist.
  • Examination of HHcy's impact on matrix metalloproteinases (MMPs) and cardiac remodeling.

Main Results:

  • HHcy induces cardiac oxidative stress and activates MMPs, degrading cellular components.
  • Cardiac remodeling due to HHcy can disrupt impulse conduction, particularly in the specialized conduction system.
  • Hcy's action on NMDA-Rs increases cardiac cell excitability, potentially leading to arrhythmias.

Conclusions:

  • HHcy-induced oxidative stress and cardiac remodeling are potential mechanisms for arrhythmogenesis and SCD.
  • Further research is needed to fully elucidate these pathways.
  • B vitamin supplementation shows potential efficacy in managing HHcy and CHD.

Related Concept Videos

Mechanism of Cardiac Arrhythmias01:28

Mechanism of Cardiac Arrhythmias

Arrhythmias are irregular heart rhythms occurring when the heart's electrical impulses become abnormal. These disturbances can lead to various symptoms, depending on their severity and the underlying cause. Some common factors contributing to arrhythmias include hypoxia, ischemia, electrolyte imbalances, excessive catecholamine exposure, drug toxicity, and muscle overstretching. Arrhythmias can be classified into two main types based on the rate and site of origin of abnormal heart rhythms.
Cardiomyopathy III: Hypertrophic Cardiomyopathy01:29

Cardiomyopathy III: Hypertrophic Cardiomyopathy

Hypertrophic cardiomyopathy, or HCM, is an autosomal dominant genetic disorder characterized by asymmetric left ventricular hypertrophy without ventricular dilation. It is more common in men and is typically diagnosed in young, athletic adults.EtiologyHCM is primarily genetic and is caused by mutations in genes encoding sarcomeric proteins. Researchers have identified over 1400 mutations across at least 11 different genes. Among these, the most frequently occurring mutations are found in the...
Blood Studies for Cardiovascular System II: CRP, Hcy, and Cardiac Natriuretic Peptide Markers01:19

Blood Studies for Cardiovascular System II: CRP, Hcy, and Cardiac Natriuretic Peptide Markers

Cardiac biomarkers are critical in diagnosing, prognosing, and managing cardiovascular diseases. Routine measurement of specific biomarkers such as B-type natriuretic peptide (BNP), C-reactive protein (CRP), and homocysteine (Hcy) is common practice in clinical settings to evaluate heart function and predict cardiovascular events.
These markers indicate stress or strain on the heart muscle:
Natriuretic Peptides (BNP)
Cardiac myocytes produce these hormones in response to ventricular stretching...
Coronary Artery Disease III: Clinical Manifestations01:30

Coronary Artery Disease III: Clinical Manifestations

Coronary Artery Disease (CAD) is a primary health risk worldwide, leading to significant morbidity and mortality. The condition arises from the buildup of atherosclerotic plaques within the coronary arteries, resulting in diminished blood supply to the heart muscle.The clinical manifestations of CAD vary widely, from asymptomatic stages to severe, life-threatening conditions. Understanding these manifestations is crucial for early diagnosis and effective management.Angina Pectoris: The Warning...
Pathophysiology of Heart Failure01:17

Pathophysiology of Heart Failure

Heart failure (HF) is a progressive syndrome involving ventricles that leads to inadequate cardiac output. It can be classified based on location and output or ejection fraction. Ejection fraction (EF) is an essential measurement in the diagnosis and surveillance of HF. Reduced EF corresponds to systolic heart failure (HFrEF). However, HF with preserved ejection fraction (HFpEF) is becoming increasingly prevalent. Also known as diastolic HF, this form of HF is related to aging. The...
Myocarditis I: Introduction01:21

Myocarditis I: Introduction

Myocarditis is inflammation of the myocardium, which is the muscular layer of the heart.EtiologyMyocarditis has a diverse etiology, including a wide range of infectious and non-infectious causes:Infectious CausesViral: Common viruses include Coxsackie A and B, adenovirus, parvovirus B19, enteroviruses, and influenza A.Bacterial: Examples include infections caused by Streptococcus, Staphylococcus, and Mycoplasma species.Rickettsial: Infections like Rocky Mountain spotted fever can result in...