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Frequency of transient reductions in left ventricular ejection fraction at rest in coronary artery disease
M R Freeman1, L de Yang, A Langer
1University of Toronto, Ontario, Canada.
Insights
Patients with coronary artery disease (CAD) experience frequent left ventricular (LV) ejection fraction (EF) reductions. Unstable angina showed the highest prevalence of LV dysfunction, indicating significant CAD impact.
Area of Science:
- Cardiology
- Nuclear Medicine
- Cardiovascular Imaging
Background:
- Coronary artery disease (CAD) can impair left ventricular (LV) function.
- Assessing LV ejection fraction (EF) at rest is crucial for understanding CAD severity.
Purpose of the Study:
- To determine the prevalence and frequency of LV ejection fraction (EF) decreases in patients with stable angina, unstable angina, and recent myocardial infarction.
- To compare LV function in CAD patients with that of normal subjects.
Main Methods:
- Continuous assessment of LV function using a novel nuclear device.
- Monitoring LV ejection fraction (EF) for extended periods in patients and healthy controls.
- Comparing episodes and duration of EF reductions between groups.
Main Results:
- Episodes of significant EF reduction were more frequent in patients with stable angina (48%), recent myocardial infarction (64%), and unstable angina (85%) compared to normal subjects (0%).
- Patients with unstable angina and recent myocardial infarction showed significantly more frequent EF decreases per hour than normal subjects.
- The duration of EF decrease was significantly longer in unstable angina patients than in normal subjects.
Conclusions:
- LV ejection fraction (EF) decreases are prevalent in patients with coronary artery disease (CAD), particularly in unstable angina.
- Continuous monitoring with nuclear devices can effectively detect transient LV dysfunction in CAD patients.
- Findings highlight the significant impact of CAD on myocardial function, especially during acute events.
Abstract:
To determine the prevalence of decreases in left ventricular (LV) ejection fraction (EF) at rest in patients with coronary artery disease (CAD), including those with stable angina (n = 21), unstable angina (n = 13), and recent myocardial infarction (n = 11), continuous assessment of LV function for 162 +/- 136 minutes was performed using a new nuclear device. The results were compared with those of a group of normal subjects (n = 10) monitored for 80 +/- 28 minutes. Episodes of EF reduction of > 7% from baseline for a total duration of > 5% monitored time occurred in 0 of 10 normal subjects; episodes were more frequent in patients with stable angina (10 of 21, 48%; p = 0.01), with recent myocardial infarction (7 of 11, 64%; p = 0.004), and with unstable angina (11 of 13, 85%; p = 0.0001). The number of EF decreases per hour in patients after myocardial infarction (1.7 +/- 2.5 [SD]) and unstable angina (1.2 +/- 0.7) was significantly more frequent than in normal subjects (0.3 +/- 0.4), but was not different from that in patients with stable angina (0.8 +/- 1.0). The duration of the decrease in EF, expressed as minutes per hour of monitored time in normal subjects (0.7 +/- 1.0%), was significantly less than in patients with unstable angina (10 +/- 8%). Patients with stable angina (6 +/- 9%) and recent myocardial infarction (6 +/- 6%) were not significantly different from normal subjects.(ABSTRACT TRUNCATED AT 250 WORDS)