Good collaterals predict viable myocardium.

Area of Science:

• Cardiology
• Interventional Cardiology
• Cardiac Imaging

Background:

• Percutaneous coronary intervention (PCI) for totally occluded coronary arteries remains controversial.
• Assessing myocardial viability before PCI is recommended but lacks practical, sensitive methods in the catheterization lab.
• Coronary collateral circulation is a potential indicator of myocardial viability.

Purpose of the Study:

• To determine if highly developed coronary collaterals predict myocardial viability in the area supplied by a totally occluded coronary artery.
• To evaluate the diagnostic accuracy of coronary collateral circulation for detecting viable myocardium.
• To inform decisions regarding revascularization strategies for chronic total occlusions.

Main Methods:

• Prospective enrollment of 47 patients with a single totally occluded coronary artery.
• Diagnostic coronary angiography to assess coronary anatomy and collateral status.
• Dobutamine stress echocardiography to determine myocardial viability in the occluded artery's territory.

Main Results:

• 18 patients (38.3%) had viable myocardium (Group A), while 29 (61.7%) had nonviable myocardium (Group B).
• Significant coronary collateral circulation was more frequent in patients with viable myocardium (66.7%) compared to nonviable (20.7%) (p=0.002).
• Good collateral circulation was an independent predictor of viable myocardium (p=0.006, OR 16.7), with 75% sensitivity and 75% positive predictive value.

Conclusions:

• Good coronary collateral circulation is a sensitive and specific predictor of myocardial viability in totally occluded coronary arteries.
• Assessing coronary collateral circulation is vital for guiding decisions on percutaneous coronary intervention versus coronary artery bypass surgery.
• This assessment offers a practical approach to identifying suitable candidates for revascularization in the catheterization laboratory.