Obtuse marginal branches
The obtuse marginal (OM) arteries sometimes referred to as lateral branches are branch coronary arteries that come off the circumflex artery. There can be one or more obtuse marginal arteries. It typically traverses along the left margin of heart towards the apex. The first obtuse marginal artery (OM1) is usually found on or close to the obtuse margin of the heart and is also known as the “margo obtusus”