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Effects of the Mueller maneuver on global and regional left ventricular function in angina pectoris with or without
Insights
Prior transmural myocardial infarction (MI) is necessary for left ventricular (LV) regional wall akinesia during the Mueller maneuver in men with coronary artery disease. Ischemic disease alone does not cause this effect.
Area of Science:
- Cardiology
- Cardiovascular Physiology
Background:
- Coronary artery disease (CAD) can lead to left ventricular (LV) dysfunction.
- The Mueller maneuver, an inspiratory effort against a closed glottis, can reveal subtle cardiac abnormalities.
Purpose of the Study:
- To determine if myocardial ischemic disease without infarction causes LV regional wall akinesia during the Mueller maneuver.
- To ascertain if prior acute myocardial infarction (MI) is a prerequisite for this phenomenon.
Main Methods:
- First-pass radionuclide ventriculography was used in men with CAD and varying degrees of MI history.
- Measurements included LV ejection fraction, volumes, and heart rate during the Mueller maneuver.
- Comparison was made between normal volunteers and patients with no prior MI, non-transmural MI, and transmural MI.
Main Results:
- LV ejection fraction decreased in all CAD groups during the Mueller maneuver, unlike normal subjects.
- Regional wall akinesia during the Mueller maneuver was observed exclusively in patients with prior transmural MI (17 out of 36).
- Akinetic segments during the Mueller maneuver were often only visualized with radionuclide ventriculography, not routine contrast studies.
Conclusions:
- Prior transmural MI, not just ischemic heart disease, is necessary for LV regional wall akinesia during the Mueller maneuver in men with CAD.
- The Mueller maneuver, combined with radionuclide ventriculography, can detect LV abnormalities not apparent on routine contrast imaging.
Abstract:
In patients with coronary artery disease, left ventricular (LV) regional wall akinesia can develop during the Mueller maneuver. The present study determines if the presence of myocardial ischemic disease with no infarction is a sufficient condition for this to occur, or if the presence of prior acute myocardial infarction (MI) is necessary. In men, first-pass radionuclide ventriculography was performed in the 30 degree left anterior oblique supine position to measure LV ejection fraction, end-diastolic and end-systolic volumes and heart rate, and to obtain an image of the LV cavitary perimeter. This procedure was performed in 4 subject groups: 13 normal volunteers, 25 patients with coronary artery disease but no prior MI, 13 patients with coronary artery disease and prior nontransmural MI, and 36 patients with coronary artery disease and prior transmural MI. All patients had angina and underwent routine contrast coronary angiography; 60 also underwent contrast coronary angiography; 60 also underwent contrast LV angiography. Ejection fraction decreased during the Mueller maneuver in each of all the coronary artery disease groups (p less than 0.01), but not in the normal subjects. Heart rate increased in groups 1, 2 and 4 (p less than 0.01), and end-diastolic volume decreased in all 4 groups (p less than 0.01), whereas end-systolic volume did not change. Only in group 4 did regional wall akinesia develop (17 patients) during the Mueller maneuver. Among patients who had akinesia during the Mueller maneuver and also underwent routine contrast ventriculography, half of the akinetic segments were not seen on routine contrast study, but were seen only on radionuclide ventriculography during the Mueller maneuver.(ABSTRACT TRUNCATED AT 250 WORDS)