Related Experiment Videos
Angiographic findings 1 month after myocardial infarction: a prospective study of 259 survivors
Insights
Coronary artery disease significantly impacts left ventricular function after myocardial infarction. However, collateral circulation can improve regional wall motion and preserve heart function in survivors.
Area of Science:
- Cardiology
- Cardiovascular Physiology
- Interventional Cardiology
Background:
- Left ventricular (LV) function is crucial after acute myocardial infarction (MI).
- Coronary anatomy and obstructive lesions play a significant role in post-MI cardiac function.
- Understanding these relationships aids in predicting patient outcomes and guiding treatment strategies.
Purpose of the Study:
- To prospectively assess the relationship between coronary anatomy and LV function in male patients surviving acute MI.
- To evaluate the impact of obstructive coronary artery lesions and collateral circulation on regional and global LV function.
Main Methods:
- Prospective study of 259 male patients (≤60 years) undergoing catheterization 30 days post-MI.
- Assessment of coronary artery anatomy, including obstructive lesions (stenosis >50%), total/subtotal occlusions, and collateral circulation.
- Evaluation of left ventricular function through ejection fraction and analysis of akinetic segments.
Main Results:
- 93% of patients had obstructive coronary lesions; 45% had total/subtotal occlusions.
- Patients with normal or non-obstructive coronary arteries had higher ejection fractions.
- Lower ejection fraction and higher akinetic segments were observed in patients with total/subtotal occlusions and no collaterals.
- Adequate collateral circulation (11% of patients) significantly improved regional wall motion and reduced akinetic segments.
Conclusions:
- Obstructive coronary artery disease is prevalent in MI survivors and negatively impacts LV function.
- Collateral circulation plays a vital role in improving myocardial function and reperfusion in the infarcted area.
- Approximately 32% of patients experience spontaneous reperfusion via collaterals or the involved artery, ameliorating wall motion deficits.
Abstract:
Coronary anatomy as it relates to left ventricular function was assessed prospectively in patients who survived acute myocardial infarction. The study population included 259 consecutive male patients age 60 years or younger who underwent catheterization 30 days after the acute event. Coronary artery obstructive lesions (greater than 50% reduction in luminal diameter) were found in 241 patients (93%), 118 (45%) of whom had total and 76 (29%) subtotal (greater than 90%) stenosis) occlusion of at least one coronary artery. Normal coronary vessels were seen in eight patients (3%) and nonobstructive lesions in 10 (4%). One-, two- and three-vessel disease were present in 89, 86 and 66 patients, respectively. Patients with normal coronary arteries or nonobstructive lesions had higher ejection fractions than those with obstructive lesions in one, two or three vessels (p less than 0.05). Ejection fraction was lower (p less than .001) and the percentage of akinetic segments higher (p less than 0.001) in patients with total or subtotal lesions and no collaterals. Adequate collaterals, seen in 29 patients (11%), significantly improved regional wall motion (p less than 0.05) and decreased the percentage of akinetic segments (p less than 0.001). Thus, in a substantial number of patients (32% in our series), the infarcted area is spontaneously reperfused by collaterals or through the involved artery. Both mechanisms ameliorate wall motion in corresponding areas.