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    Related Topics

    From Cardiovascular System

    Median Cubital Vein
    Connects cephalic and basilic veins at the elbow.
    Crista Terminalis
    Smooth muscular ridge in the right atrium.
    Pericardium
    Double-walled sac containing the heart and the roots of the great vessels.
    Descending Aorta
    Portion of the aorta descending through thorax and abdomen.
    Ulnar Arteries
    Supply the medial aspect of the forearm and hand.
    Brachiocephalic Trunk
    First major branch off the aortic arch.
    Trabeculae Carneae
    Irregular muscular columns on the walls of the ventricles.
    Radial Arteries
    Supply the lateral aspect of the forearm and hand.
    Cephalic Veins
    Superficial veins of the lateral upper limb.
    Internal Carotid Artery
    Supplies blood to the brain.
    Papillary Muscles
    Muscles that anchor the heart valves via chordae tendineae.
    Anterior Cardiac Veins
    Drain directly into the right atrium.
    Subclavian Arteries
    Supply blood to the arms and part of the brain.
    Great Saphenous Vein
    Longest vein in the body, running along the leg.
    Small Cardiac Vein
    Drains right atrium and ventricle.
    Right Superior Pulmonary Vein
    Returns oxygenated blood from right lung.
    Anterior Interventricular Branch
    Supplies anterior interventricular septum (LAD).
    Auricles
    Small muscular pouches of each atrium.
    Ascending Aorta
    Initial portion of the aorta emerging from the heart.
    External Jugular Veins
    Drain blood from the face and scalp.
    External Iliac Veins
    Drain lower limbs and join internal iliac veins.
    Left Inferior Pulmonary Vein
    Returns oxygenated blood from left lung.
    Axillary Veins
    Drain the upper limbs and join with subclavian veins.
    Coronary Sinus
    Collects blood from coronary veins.
    Circumflex Branch
    Curves around to the posterior heart.

    Marginal Branch

    Reviewed by our medical team

    Supplies right ventricle along the margin.

    Overview

    The marginal branch, commonly referring to the right marginal branch of the right coronary artery (RCA), is an important arterial vessel that supplies blood to the right ventricle of the heart. It is one of the key branches of the RCA and plays a significant role in maintaining adequate perfusion to the anterior portion of the right heart. Occasionally, the term "marginal branch" may also refer to the obtuse marginal branches of the left circumflex artery (LCx), which supply the lateral wall of the left ventricle. However, unless otherwise specified, "marginal branch" typically refers to the right marginal artery.

    Location

    The right marginal branch originates from the right coronary artery as it courses along the right atrioventricular (coronary) sulcus. The branch emerges near the inferior border (acute margin) of the heart and runs toward the apex. It travels along the anterior surface of the right ventricle, often visible on the external surface of the heart during dissection or imaging.

    In contrast, obtuse marginal branches (OM1, OM2, etc.) arise from the LCx and run along the left lateral margin of the heart, supplying the lateral wall of the left ventricle.

    Structure

    The right marginal branch is a relatively large artery that travels superficially along the right border of the heart. It is often accompanied by a marginal vein, which drains into the small cardiac vein. The artery itself is a muscular, medium-caliber vessel and follows a relatively straight course toward the apex of the heart.

    Its origin and branching pattern may vary slightly between individuals, but it typically branches off from the mid-portion of the right coronary artery.

    Function

    The primary function of the right marginal branch is to supply oxygenated blood to the:

    • Anterior portion of the right ventricle

    • Right border of the heart (acute margin)

    • Occasionally the apex of the heart, through collateral supply

    This perfusion is crucial to maintain contractility and electrical activity of the right ventricular free wall.

    Physiological Role(s)

    The marginal branch supports several key physiological roles in cardiovascular function:

    • Ventricular contraction: By perfusing the right ventricular myocardium, it ensures proper contraction during systole, essential for pulmonary circulation.

    • Electrophysiological stability: The artery indirectly supports the electrical conduction system by maintaining viable myocardium in areas near conduction pathways.

    • Collateral circulation: In cases of partial coronary occlusion, the marginal artery may contribute to collateral flow to the left or posterior heart regions.

    Clinical Significance

    The right marginal branch has considerable clinical importance in both ischemic and interventional cardiology:

    • Coronary Artery Disease (CAD): Atherosclerosis can affect the right marginal branch, leading to ischemia of the right ventricle. Symptoms may include chest pain, arrhythmias, or right-sided heart failure.

    • Myocardial Infarction: Occlusion of the right coronary artery proximal to the marginal branch can cause infarction in the right ventricular free wall. This is often identified on ECG with ST elevation in right-sided chest leads.

    • Percutaneous Coronary Intervention (PCI): The marginal branch is frequently visualized and sometimes stented during right coronary angioplasty if significant stenosis is present.

    • Bypass Surgery: In cases of multivessel coronary disease, the marginal branch may be bypassed using a graft, especially if it supplies a large territory of viable myocardium.

    • Imaging: Coronary angiography and CT angiography help visualize the marginal branch for diagnosis and surgical planning.

    • Anatomical Variants: The number and size of marginal branches can vary; some individuals may have multiple right marginal arteries, while others have a dominant single vessel.

    Proper understanding of the marginal branch's anatomy and variability is essential during cardiac catheterization, coronary surgery, and in the management of right ventricular infarctions.

    Did you know? Oxygenated blood is carried to the heart via the pulmonary veins.