Chronic total occlusions (CTO) are a progressive form of coronary artery disease, where the entire vessel is blocked by cholesterol and inflammatory cells, preventing any blood to flow to the heart muscle. Often adjacent blood vessels will form collateral blood flow to keep the heart muscle alive.
Symptoms of CTO are similar to angina and heart failure and include:
The diagnostic modality of choice is coronary angiography to define which vessel and the length of vessel occluded. Echocardiography is useful to determine which part of the heart muscle is starved of blood. Viablility stress testing often help determine the degree and size of ischemia (low blood flow state).
Treatment options include conservative medical therapy to alleviate symptoms of chest pain and shortness of breath. For symptomatic patients, they may require advanced treatments which include minimally-invasive catheterization techniques or bypass surgery to completely restore all blood flow to the heart muscle.