Related Experiment Videos
Influence of right ventricular ischemia on precordial ST depression during right coronary artery occlusion
1Second Department of Internal Medicine, Oita Medical University, Japan.
Insights
Precordial ST depression in acute inferior myocardial infarction often indicates reciprocal ST deviation reflecting inferoposterior involvement. Right ventricular involvement lessens this precordial ST depression.
Area of Science:
- Cardiology
- Medical Research
Background:
- Precordial ST depression is observed in acute inferior myocardial infarction.
- The underlying cause and relationship with ventricular involvement require clarification.
Purpose of the Study:
- To investigate the cause of precordial ST depression in acute inferior myocardial infarction.
- To evaluate the correlation between precordial ST deviation and ventricular involvement.
Main Methods:
- Analysis of 49 patients with acute inferior myocardial infarction and 60 patients undergoing elective right coronary artery angioplasty.
- Patients categorized into two groups based on lesion proximity to the right ventricular branch.
- Comparison of inferior ST elevation and precordial ST depression between groups.
Main Results:
- No significant difference in inferior ST elevation between groups.
- Greater precordial ST depression observed in patients with lesions distal to the right ventricular branch (Group B).
- Significant correlation between inferior and precordial ST deviation found only in Group B.
Conclusions:
- Precordial ST depression in inferior infarction is likely reciprocal ST deviation indicating inferoposterior involvement.
- Right ventricular involvement in inferior infarction is associated with reduced precordial ST depression.
Abstract:
To determine the cause of precordial ST depression in acute inferior myocardial infarction, we evaluated the relationship between precordial ST deviation and ventricular involvement. Forty-nine patients who were admitted to the hospital with an acute inferior myocardial infarction, and 60 patients who were treated with elective angioplasty to the right coronary artery, were analyzed. All patients had single vessel disease and were divided into 2 groups (A and B) according to the site of the lesion. Patients in group A had a lesion proximal to the largest right ventricular branch, while in group B the lesion was distal to that branch. There were no differences in inferior ST elevation between the 2 groups, but precordial ST segments were more depressed in group B than in group A. A significant correlation was observed between inferior and precordial ST deviation in group B, but not in group A. These results were similar in patients with myocardial infarction and in those treated by angioplasty. These results suggest that precordial ST depression in an evolving inferior infarction is due to reciprocal ST deviation which reflects inferoposterior involvement. In addition, when inferior infarction is accompanied by right ventricular involvement the precordial ST depression is lessened.