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    Related Topics

    From Cardiovascular System

    Tricuspid Valve
    Valve between the right atrium and right ventricle.
    Right Superior Pulmonary Vein
    Returns oxygenated blood from right lung.
    Auricles
    Small muscular pouches of each atrium.
    Abdominal Aorta
    Part of descending aorta within the abdomen.
    Left Common Carotid Artery
    Supplies the head and neck.
    Subclavian Arteries
    Supply blood to the arms and part of the brain.
    External Iliac Veins
    Drain lower limbs and join internal iliac veins.
    Left Inferior Pulmonary Vein
    Returns oxygenated blood from left lung.
    Small Cardiac Vein
    Drains right atrium and ventricle.
    Common Carotid Arteries
    Major arteries supplying blood to the head and neck.
    Pulmonary Valve
    Valve between right ventricle and pulmonary trunk.
    External Carotid Artery
    Supplies blood to the face and scalp.
    Superior Vena Cava
    Returns deoxygenated blood from upper body.
    Radial Arteries
    Supply the lateral aspect of the forearm and hand.
    Right Coronary Artery
    Supplies blood to right side of heart.
    Small Saphenous Vein
    Superficial vein of the posterior leg.
    Left Atrium
    Receives oxygenated blood from the lungs.
    Axillary Veins
    Drain the upper limbs and join with subclavian veins.
    Brachiocephalic Veins
    Formed by the union of subclavian and internal jugular veins.
    Ascending Aorta
    Initial portion of the aorta emerging from the heart.
    External Jugular Veins
    Drain blood from the face and scalp.
    Axillary Arteries
    Continuation of subclavian arteries into the armpit.
    Aortic Arch
    Curved portion of the aorta giving rise to major arteries.
    Coronary Sinus
    Collects blood from coronary veins.
    Descending Aorta
    Portion of the aorta descending through thorax and abdomen.

    Right Pulmonary Artery

    Reviewed by our medical team

    Carries blood to right lung.

    Overview

    The right pulmonary artery is one of the two branches of the pulmonary trunk that transports deoxygenated blood from the right ventricle to the right lung. Despite being an artery, it carries oxygen-poor blood — a unique feature of pulmonary arteries compared to systemic arteries. The right pulmonary artery plays a central role in pulmonary circulation by delivering blood to the right lung for oxygenation.

    Location

    The right pulmonary artery arises from the pulmonary trunk at the level of the sternal angle (around T5–T6 vertebrae). It travels:

    • Horizontally to the right, passing posterior to the ascending aorta and superior vena cava

    • Anterior to the right main bronchus

    • Enters the right lung at the hilum as part of the root of the lung

    Once inside the lung, it divides into lobar and then segmental arteries to supply all regions of the right lung.

    Structure

    The right pulmonary artery is a thick-walled, elastic artery adapted for high-volume, low-pressure blood flow. It typically has:

    • Origin: Pulmonary trunk

    • Course: Longer and larger than the left pulmonary artery due to the heart's left-sided position

    • Diameter: Approximately 1.5–2.5 cm in adults

    • Wall composition: Tunica intima (endothelium), tunica media (elastic fibers and smooth muscle), and tunica adventitia

    At the hilum, the right pulmonary artery typically lies anterior to the bronchus and superior to the pulmonary veins.

    Function

    The primary function of the right pulmonary artery is to:

    • Transport deoxygenated blood from the right ventricle to the right lung

    There, the blood flows through smaller arteries, arterioles, and capillaries surrounding the alveoli, allowing gas exchange to occur. The now oxygenated blood returns to the left atrium via the right pulmonary veins.

    Physiological Role(s)

    The right pulmonary artery contributes to several physiological processes:

    • Gas exchange support: Delivers blood to alveolar capillaries for oxygen uptake and carbon dioxide release

    • Low-pressure circulation: Operates under significantly lower pressure than systemic arteries to protect delicate pulmonary capillaries

    • Dynamic flow adjustment: Can constrict or dilate in response to oxygen levels, optimizing ventilation-perfusion matching

    • Right ventricular afterload regulation: Its resistance influences right ventricular workload and output

    Clinical Significance

    The right pulmonary artery is central to several cardiopulmonary conditions and clinical procedures:

    • Pulmonary Hypertension: Increased pressure in the pulmonary arteries leads to right ventricular hypertrophy and failure. Often involves both left and right pulmonary arteries.

    • Pulmonary Embolism (PE): A clot may lodge in the right pulmonary artery, reducing blood flow to the right lung and causing hypoxia, chest pain, or sudden death.

    • Pulmonary Artery Stenosis: Narrowing of the right pulmonary artery (congenital or acquired) can cause reduced lung perfusion and right-sided pressure overload.

    • Congenital Heart Disease: Abnormal development of the right pulmonary artery may be seen in conditions like Tetralogy of Fallot or truncus arteriosus. Surgical correction is often required.

    • Right Heart Catheterization: The right pulmonary artery is a target site during catheter-based hemodynamic studies to measure pulmonary artery pressures and cardiac output.

    • Imaging: CT pulmonary angiography and echocardiography are critical tools for assessing right pulmonary artery size, flow, and pathology.

    Timely diagnosis and treatment of right pulmonary artery-related conditions are essential to prevent complications such as hypoxemia, pulmonary infarction, or right heart failure.

    Did you know? The heart is about the size of your fist and weighs less than a pound.