Related Experiment Video

Updated: Aug 29, 2026

A Method to Study the Correlation Between Local Collagen Structure and Mechanical Properties of Atherosclerotic Plaque Fibrous Tissue
13:45

A Method to Study the Correlation Between Local Collagen Structure and Mechanical Properties of Atherosclerotic Plaque Fibrous Tissue

Published on: November 11, 2022

Circadian variation of plaque rupture in acute myocardial infarction

Atsushi Tanaka1, Takahiko Kawarabayashi, Daiju Fukuda

  • 1Baba Memorial Hospital, Sakai, Japan. m4497147@msic.med.osaka-cu.ac.jp

The American Journal of Cardiology
|December 31, 2003
PubMed

Insights

Acute myocardial infarction (AMI) shows a morning peak, driven by increased plaque rupture. This contrasts with non-rupture cases, which peak overnight, revealing distinct circadian patterns in AMI causes.

Area of Science:

  • Cardiology
  • Circadian Biology
  • Medical Imaging

Background:

  • Circadian variations in acute myocardial infarction (AMI) onset are established.
  • Plaque rupture is a primary cause of AMI, but its specific circadian pattern is understudied.

Purpose of the Study:

  • To investigate the circadian variation of plaque rupture in patients with AMI using intravascular ultrasound (IVUS).

Main Methods:

  • 174 consecutive AMI patients underwent pre-interventional IVUS.
  • Patients were categorized into plaque rupture or non-rupture groups based on IVUS findings.

Main Results:

  • The plaque rupture group showed a significant increase in AMI onset between 6 AM and 12 PM (p < 0.05).
  • AMI in the rupture group occurred more frequently at rest (67% vs 31%) and with less pre-infarction angina (22% vs 57%).
  • The non-rupture group exhibited a significant nocturnal nadir in AMI onset (12 AM to 6 AM).

Conclusions:

  • The circadian variation of AMI onset is significantly influenced by the timing of plaque rupture.
  • A morning increase in plaque rupture incidence underlies the observed circadian pattern in AMI.

More Related Videos

A Microscopic 2,3,5-Triphenyltetrazolium Chloride Assay for Accurate and Reliable Analysis of Myocardial Injury11:17

A Microscopic 2,3,5-Triphenyltetrazolium Chloride Assay for Accurate and Reliable Analysis of Myocardial Injury

Published on: November 28, 2025

Real-time Pressure-volume Analysis of Acute Myocardial Infarction in Mice07:28

Real-time Pressure-volume Analysis of Acute Myocardial Infarction in Mice

Published on: July 2, 2018

Related Concept Videos

Coronary Artery Disease II: Pathophysiology01:26

Coronary Artery Disease II: Pathophysiology

Coronary Artery Disease (CAD) originates from a series of events that impair the function of coronary arteries, the blood vessels responsible for delivering oxygen-rich blood to the heart muscle. The pathophysiology of CAD is closely linked to atherosclerosis, a chronic inflammatory and lipid-driven condition affecting the vascular endothelium.1. Endothelial DamageThe process begins with damage to the vascular endothelium, which serves as a protective barrier between the blood and the vessel...
Chronopharmacokinetics: Circadian Rhythms and Influence on Drug Response01:15

Chronopharmacokinetics: Circadian Rhythms and Influence on Drug Response

Circadian rhythms are cyclic changes that are crucial in plasma drug concentrations. Various standard circadian parameters, including core body temperature, heart rate, and other cardiovascular factors, directly impact disease states and the therapeutic response to drug therapy.
The time of drug administration is an important factor to consider, as it can influence the toxic dose of a drug. For example, a study conducted by Prins et al. in 1997 examined the effects of the timing of...
Acute Coronary Syndrome III: Diagnostic Studies01:30

Acute Coronary Syndrome III: Diagnostic Studies

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...
Blood Studies for Cardiovascular System I: Cardiac Biomarkers01:20

Blood Studies for Cardiovascular System I: Cardiac Biomarkers

Cardiac biomarkers are enzymes, proteins, and hormones released into the blood when cardiac cells are injured. They are powerful tools for triaging.
The essential diagnostic tools for detecting myocardial necrosis and monitoring individuals suspected of having acute coronary syndrome (ACS) include:
Troponins
Troponins, particularly cardiac troponins I and T, are the most precise and sensitive markers of myocardial injury. They are detectable within 4-6 hours of myocardial injury and remain...
Acute Coronary Syndrome I: Introduction01:30

Acute Coronary Syndrome I: Introduction

Acute Coronary Syndrome (ACS) encompasses a spectrum of heart conditions caused by sudden obstruction of coronary arteries, typically resulting from the rupture of an atherosclerotic plaque and subsequent thrombus (blood clot) formation. This obstruction can lead to partial or complete blockage of blood flow, causing varying degrees of myocardial ischemia or infarction.ACS includes the following clinical entities:Unstable Angina (UA)Non-ST-Elevation Myocardial Infarction (NSTEMI)ST-Elevation...
Atherosclerosis I: Introduction01:30

Atherosclerosis I: Introduction

Atherosclerosis is a progressive disorder characterized by the buildup of plaques on the arterial inner wall, causing them to narrow and harden over time. These plaques comprise lipids, calcium, blood components, carbohydrates, and fibrous tissue. The process primarily affects the intima of large and medium-sized arteries, reducing blood flow in any artery.Etiology and risk factorsThe cause of atherosclerosis is multifactorial, involving a complex interplay among endothelial injury, lipid...