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A Research Method For Detecting Transient Myocardial Ischemia In Patients With Suspected Acute Coronary Syndrome Using Continuous ST-segment Analysis
18:11

A Research Method For Detecting Transient Myocardial Ischemia In Patients With Suspected Acute Coronary Syndrome Using Continuous ST-segment Analysis

Published on: December 28, 2012

[The clinical relevant factors of the myocardial ischemic threshold]

D Lu1

  • 1First Affiliated Hospital, Zhejiang Medical University, Hangzhou.

Zhonghua Xin Xue Guan Bing Za Zhi
|December 1, 1992
PubMed

Insights

The heart rate at which ischemia occurs varies significantly throughout the day in coronary heart disease patients. This myocardial ischemic threshold variability may indicate disease severity and patient prognosis.

Area of Science:

  • Cardiology
  • Cardiovascular Physiology

Context:

  • Assessed myocardial ischemic threshold (MIT) in 92 coronary heart disease (CHD) patients.
  • MIT is the heart rate at which myocardial ischemia begins.

Purpose:

  • To evaluate the diurnal variation in MIT among CHD patients.
  • To explore correlations between MIT variability and clinical factors.

Summary:

  • Highest MIT occurred during daytime activities (122 +/- 18 bpm), while lowest MIT (82 +/- 17 bpm) occurred during early morning or sleep.
  • Mean MIT variability (VMIT) was 30.22%, positively correlated with ischemic episodes and negatively with lowest MIT.
  • VMIT was significantly higher in senior-aged patients compared to middle-aged patients (P < 0.001).

Impact:

  • Findings suggest LMIT and VMIT may reflect coronary lesion severity, coronary tonus, and patient prognosis.
  • Understanding MIT diurnal patterns can inform clinical management and risk stratification in CHD.

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