Plasma homocysteine levels associated with a corrected QT interval
Zhao Li1, Xiaofan Guo1, Guozhe Sun1
1Department of Cardiology, the First Hospital of China Medical University, 155 Nanjing North Street, Heping District, Shenyang, 110001, People's Republic of China.
BMC Cardiovascular Disorders
|July 12, 2017
Summary
Elevated homocysteine (Hcy) levels are linked to prolonged QT intervals in the general population. This study found increased odds of a longer QTc interval in those with the lowest and highest Hcy levels.
Area of Science:
- Cardiology
- Clinical Biochemistry
- Public Health
Background:
- The relationship between homocysteine (Hcy) levels and QT interval duration is not well understood.
- Homocysteine is an amino acid linked to cardiovascular disease.
- The QT interval on an electrocardiogram (ECG) reflects cardiac repolarization.
Purpose of the Study:
- To investigate the association between homocysteine levels and corrected QT (QTc) intervals.
- To determine if varying homocysteine concentrations correlate with altered QTc durations in a general population.
Main Methods:
- A population-based study included 7002 participants aged 35 years and older.
- Plasma homocysteine levels were measured.
- Twelve-lead ECGs were performed and automatically analyzed to determine QTc intervals.
Main Results:
- Participants were divided into four homocysteine level quartiles.
- The lowest (Q1) and highest (Q4) homocysteine quartiles showed increased odds of a QTc interval greater than 440 ms compared to the second quartile (Q2).
- Adjusted odds ratios were 1.23 for Q1 and 1.40 for Q4, both with P < 0.05.
Conclusions:
- A significant association exists between homocysteine levels and QTc interval duration in the general population.
- Both low and high homocysteine levels may be associated with prolonged QTc intervals.
- Further research is warranted to elucidate the clinical implications of this association.
Related Concept Videos
01:19Blood Studies for Cardiovascular System II: CRP, Hcy, and Cardiac Natriuretic Peptide Markers
651
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...
These markers indicate stress or strain on the heart muscle:
Natriuretic Peptides (BNP)
Cardiac myocytes produce these hormones in response to ventricular stretching...
651
01:15Pharmacodynamic Models: Linear Concentration–Effect Model
32
The linear concentration–effect model, underpinned by the principle that pharmacological effect (E) is directly proportional to plasma drug concentration (C), emerges as a pivotal simplification of the Emax model for conditions where C is significantly less than EC50. This model portrays a linear trajectory of the concentration–effect relationship when drug levels are markedly below the EC50 threshold.Despite its inherent assumption of continuous effect augmentation with increasing...
32
01:29Electrocardiogram
7.1K
An electrocardiogram (ECG or EKG) is a critical diagnostic tool that records the electrical signals produced by the heart during each heartbeat. This recording is achieved through electrodes placed strategically on the arms, legs, and chest. The electrocardiograph amplifies these signals and produces 12 distinct tracings, offering a comprehensive understanding of the heart's electrical activity.
Three major waveforms are present in a typical ECG recording: the P wave, the QRS complex, and...
Three major waveforms are present in a typical ECG recording: the P wave, the QRS complex, and...
7.1K
01:30Acute Coronary Syndrome III: Diagnostic Studies
334
Diagnosing acute coronary syndrome or ACS begins with a thorough patient history. Notable symptoms include central, crushing chest pain radiating to the left arm, neck, jaw, or back, along with shortness of breath, sweating (diaphoresis), nausea, vomiting, dizziness, and palpitations.It is crucial to note any history of cardiac illnesses and assess risk factors, including age, gender, smoking, hypertension, diabetes, hyperlipidemia, and a sedentary lifestyle.During physical examination, vital...
334
01:22Effect of Hepatic Disease on Pharmacokinetics: Pathophysiologic Assessment and Liver Function Test
244
In clinical practice, the direct measurement of hepatic blood flow to evaluate liver function presents significant challenges due to the intricate and specialized nature of the necessary techniques. Consequently, healthcare professionals often rely on empirical estimates derived from thorough patient examinations and liver function tests to gauge liver health. Among the tools at their disposal, the Child–Pugh and MELD scoring systems stand out for their ability to categorize and assess...
244
01:29Pharmacogenetic Phenotypes: Alterations in Pharmacokinetics, Drug Targets and Biologic Milieu
57
Genetic variations significantly influence drug response through pharmacokinetics, receptor interactions, and biologic milieu modifications. Pharmacokinetic alterations impact drug metabolism and clearance, affecting efficacy and toxicity. Variants in drug-metabolizing enzymes, such as CYP2C9 and CYP2C19, alter drug activation and elimination. For example, CYP2C9 loss-of-function variants require lower warfarin doses to prevent excessive bleeding, while CYP2C19 variants reduce clopidogrel...
57