Pulmonary vein

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Pulmonary vein
Diagram of the human heart (cropped).svg
Anterior (frontal) view of the opened heart. White arrows indicate normal blood flow.
Alveoli diagram.png
Diagram of the alveoli with both cross-section and external view.
Details
Precursor Truncus arteriosus
System Circulatory system
Drains from Lungs
Drains to Left atrium
Artery Pulmonary artery
Identifiers
Latin venae pulmonales
MeSH D011667
TA98 A12.3.02.001
TA2 4107
FMA 66643
Anatomical terminology
Openings of pulmonary veins.png

The pulmonary veins are the veins that transfer oxygenated blood from the lungs to the heart. The largest pulmonary veins are the four main pulmonary veins, two from each lung that drain into the left atrium of the heart. The pulmonary veins are part of the pulmonary circulation.

Contents

Structure

There are four main pulmonary veins, two from each lung – an inferior and a superior main vein, emerging from each hilum. The main pulmonary veins receive blood from three or four feeding veins in each lung, and drain into the left atrium. The peripheral feeding veins do not follow the bronchial tree. They run between the pulmonary segments from which they drain the blood. [1]

At the root of the lung, the right superior pulmonary vein lies in front of and a little below the pulmonary artery; the inferior is situated at the lowest part of the lung hilum. Behind the pulmonary artery is the bronchus. [2] The right main pulmonary veins (contains oxygenated blood) pass behind the right atrium and superior vena cava; the left in front of the descending thoracic aorta.[ citation needed ]

Variation

Occasionally the three lobar veins on the right side remain separate, and not infrequently the two left lobar veins end by a common opening into the left atrium. Therefore, the number of pulmonary veins opening into the left atrium can vary between three and five in the healthy population.[ citation needed ]

The two left lobar veins may be united as a single pulmonary vein in about 25% of people; the two right veins may be united in about 3%. [2]

Function

The pulmonary veins play an essential role in respiration, by receiving blood that has been oxygenated in the alveoli and returning it to the left atrium.[ citation needed ]

Clinical significance

As part of the pulmonary circulation they carry oxygenated blood back to the heart, as opposed to the veins of the systemic circulation which carry deoxygenated blood.[ citation needed ] By definition, a vein is a blood vessel that carries blood to the heart, whether oxygenated or deoxygenated.

A groundbreaking study published in 1998 identified the pulmonary vein as the predominant trigger for atrial fibrillation. [3] Atrial fibrillation frequently results from bursts of tachycardia that originate in muscle bundles extending from the atrium to the pulmonary veins. [4] Pulmonary vein anatomy is highly variable among atrial fibrillation patients. [5] Pulmonary vein isolation by transcatheter ablation can restore sinus rhythm. [4] As atrial fibrillation becomes more persistent, the junction between the pulmonary veins and the left atrium becomes less of an initiator and the left atrium becomes an independent source of arrhythmias. [6] Pulmonary vein isolation ablation technology has used thermal methods (radiofrequency ablation or cryoablation), which can damage adjacent tissues, notably the esophagus, lung or phrenic nerve. [7] Electroporation, however, eliminates the risk of thermal damage. [7] Atrial fibrillation most often recurs after ablation because of pulmonary vein reconnection. [8]

On chest X-ray, the diameters of pulmonary veins increases from upper to lower lobes, from 3 mm at the first intercoastal space, to 6 mm just above the diaphragm. [9]

A rare genetic defect of the pulmonary veins can cause them to drain into the pulmonary circulation in whole or in part, this is known as a total anomalous pulmonary venous connection (or drainage), or partial anomalous pulmonary connection, respectively.[ citation needed ]

Additional images

See also

Related Research Articles

<span class="mw-page-title-main">Artery</span> Blood vessels that carry blood away from the heart

An artery is a blood vessel in humans and most other animals that takes oxygenated blood away from the heart in the systemic circulation to one or more parts of the body. Exceptions that carry deoxygenated blood are the pulmonary arteries in the pulmonary circulation that carry blood to the lungs for oxygenation, and the umbilical arteries in the fetal circulation that carry deoxygenated blood to the placenta. It consists of a multi-layered artery wall wrapped into a tube-shaped channel.

<span class="mw-page-title-main">Heart</span> Organ found inside most animals

The heart is a muscular organ found in most animals. This organ pumps blood through the blood vessels of the circulatory system. The pumped blood carries oxygen and nutrients to the body, while carrying metabolic waste such as carbon dioxide to the lungs. In humans, the heart is approximately the size of a closed fist and is located between the lungs, in the middle compartment of the chest, called the mediastinum.

<span class="mw-page-title-main">Vein</span> Blood vessels that carry blood towards the heart

Veins are blood vessels in the circulatory system of humans and most other animals that carry blood towards the heart. Most veins carry deoxygenated blood from the tissues back to the heart; exceptions are those of the pulmonary and fetal circulations which carry oxygenated blood to the heart. In the systemic circulation, arteries carry oxygenated blood away from the heart, and veins return deoxygenated blood to the heart, in the deep veins.

<span class="mw-page-title-main">Circulatory system</span> Organ system for circulating blood in animals

The circulatory system is a system of organs that includes the heart, blood vessels, and blood which is circulated throughout the entire body of a human or other vertebrate. It includes the cardiovascular system, or vascular system, that consists of the heart and blood vessels. The circulatory system has two divisions, a systemic circulation or circuit, and a pulmonary circulation or circuit. Some sources use the terms cardiovascular system and vascular system interchangeably with circulatory system.

<span class="mw-page-title-main">Ventricle (heart)</span> Chamber of the heart

A ventricle is one of two large chambers located toward the bottom of the heart that collect and expel blood towards the peripheral beds within the body and lungs. The blood pumped by a ventricle is supplied by an atrium, an adjacent chamber in the upper heart that is smaller than a ventricle. Interventricular means between the ventricles, while intraventricular means within one ventricle.

<span class="mw-page-title-main">Pulmonary artery</span> Artery in pulmonary circulation carrying deoxygenated blood from heart to lungs

A pulmonary artery is an artery in the pulmonary circulation that carries deoxygenated blood from the right side of the heart to the lungs. The largest pulmonary artery is the main pulmonary artery or pulmonary trunk from the heart, and the smallest ones are the arterioles, which lead to the capillaries that surround the pulmonary alveoli.

<span class="mw-page-title-main">Pulmonary circulation</span> Part of the circulatory system which carries blood from heart to lungs and back to the heart

The pulmonary circulation is a division of the circulatory system in all vertebrates. The circuit begins with deoxygenated blood returned from the body to the right atrium of the heart where it is pumped out from the right ventricle to the lungs. In the lungs the blood is oxygenated and returned to the left atrium to complete the circuit.

<span class="mw-page-title-main">Atrium (heart)</span> Part of the human heart

The atrium is one of the two upper chambers in the heart that receives blood from the circulatory system. The blood in the atria is pumped into the heart ventricles through the atrioventricular mitral and tricuspid heart valves.

<span class="mw-page-title-main">Catheter ablation</span> Removal or termination of an electrical pathway from parts of the heart

Catheter ablation is a procedure that uses radio-frequency energy or other sources to terminate or modify a faulty electrical pathway from sections of the heart of those who are prone to developing cardiac arrhythmias such as atrial fibrillation, atrial flutter and Wolff-Parkinson-White syndrome. If not controlled, such arrhythmias increase the risk of ventricular fibrillation and sudden cardiac arrest. The ablation procedure can be classified by energy source: radiofrequency ablation and cryoablation.

<span class="mw-page-title-main">Transposition of the great vessels</span> Group of congenital heart defects

Transposition of the great vessels (TGV) is a group of congenital heart defects involving an abnormal spatial arrangement of any of the great vessels: superior and/or inferior venae cavae, pulmonary artery, pulmonary veins, and aorta. Congenital heart diseases involving only the primary arteries belong to a sub-group called transposition of the great arteries (TGA), which is considered the most common congenital heart lesion that presents in neonates.

<span class="mw-page-title-main">Bronchial artery</span> Blood vessels supplying the lungs

In human anatomy, the bronchial arteries supply the lungs with oxygenated blood, and nutrition. Although there is much variation, there are usually two bronchial arteries that run to the left lung, and one to the right lung, and are a vital part of the respiratory system.

<span class="mw-page-title-main">Tricuspid atresia</span> Malformation where the heart lacks the tricuspid valve

Tricuspid atresia is a form of congenital heart disease whereby there is a complete absence of the tricuspid valve. Therefore, there is an absence of right atrioventricular connection. This leads to a hypoplastic (undersized) or absent right ventricle. This defect is contracted during prenatal development, when the heart does not finish developing. It causes the systemic circulation to be filled with relatively deoxygenated blood. The causes of tricuspid atresia are unknown.

<span class="mw-page-title-main">Fetal circulation</span> Circulatory system of fetuses

In humans, the circulatory system is different before and after birth. The fetal circulation is composed of the placenta, umbilical blood vessels encapsulated by the umbilical cord, heart and systemic blood vessels. A major difference between the fetal circulation and postnatal circulation is that the lungs are not used during the fetal stage resulting in the presence of shunts to move oxygenated blood and nutrients from the placenta to the fetal tissue. At birth, the start of breathing and the severance of the umbilical cord prompt various changes that quickly transform fetal circulation into postnatal circulation.

<span class="mw-page-title-main">Coronary sinus</span> Set of veins which drain blood from the myocardium (heart muscle)

The coronary sinus is the largest vein of the heart. It drains over half of the deoxygenated blood from the heart muscle into the right atrium. It begins on the backside of the heart, in between the left atrium, and left ventricle; it begins at the junction of the great cardiac vein, and oblique vein of the left atrium. It receives multiple tributaries. It passes across the backside of the heart along a groove between left atrium and left ventricle, then drains into the right atrium at the orifice of the coronary sinus.

<span class="mw-page-title-main">Smallest cardiac veins</span> Small veins in the walls of all four heart chambers

The smallest cardiac veins are small, valveless veins in the walls of all four heart chambers that drain venous blood from the myocardium directly into any of the heart chambers.

<span class="mw-page-title-main">Atrial fibrillation</span> Irregular beating of the atria of the heart

Atrial fibrillation is an abnormal heart rhythm (arrhythmia) characterized by rapid and irregular beating of the atrial chambers of the heart. It often begins as short periods of abnormal beating, which become longer or continuous over time. It may also start as other forms of arrhythmia such as atrial flutter that then transform into AF.

<span class="mw-page-title-main">Bronchial circulation</span> Circulation of blood supplying lungs tissues

The bronchial circulation is the part of the systemic circulation that supplies nutrients and oxygen to the cells that constitute the lungs, as well as carrying waste products away from them. It is complementary to the pulmonary circulation that brings deoxygenated blood to the lungs and carries oxygenated blood away from them in order to oxygenate the rest of the body.

Raghib syndrome is rare a congenital heart defect where the left superior vena cava (LSVC) is draining into the left atrium in addition to an absent coronary sinus and an atrial septal defect. This can be considered a dangerous heart condition because it puts the individual at a high risk of stroke. Other defects that are often associated with Raghib syndrome can include ventricular septal defects, enlargement of the tricuspid annulus, and pulmonary stenosis. While this is considered an extremely rare developmental complex, cases regarding a persistent left superior vena cava (PLSVC) are relatively common among congenital heart defects. It is also important to note that the PLSVC often drains into the right atrium, and only drains into the left atrium in approximately 10 to 20% of individuals with the defect.

Ganglionated plexi (GP) comprise the intrinsic cardiac autonomic nervous system composed of autonomic ganglia of the heart atrium and ventricles. The GP are embedded in the epicardial fat pads, consisting of only a few neurons or as many as 400 neurons. GP are spatially close to the pulmonary veins, such that pulmonary vein isolation necessarily affects the GP. GP has been shown to be a contributor to atrial fibrillation (AFib), such that ablation of the GP has been a strategy for treatment of AFib. Pulsed field ablation has shown to be an AFib ablation strategy which effectively destroys the GP. GP ablation alone has been shown to eliminate AFib in approximately three-quarter of AFib patients.

Pulsed field ablation (PFI) is a non-thermal method of biological ablation utilizing high-amplitude pulsed electric fields to create irreversible electroporation in tissues. It is used most widely to treat tumors (cancer) or cardiac arrhythmias.

References

PD-icon.svgThis article incorporates text in the public domain from page 642 of the 20th edition of Gray's Anatomy (1918)

  1. Drake, Richard L.; Vogl, Wayne; Tibbitts, Adam W.M. Mitchell; illustrations by Richard; Richardson, Paul (2005). Gray's anatomy for students (Pbk. ed.). Philadelphia: Elsevier/Churchill Livingstone. ISBN   978-0-443-06612-2.
  2. 1 2 Skandalakis, John E. (2004). "Chapter 7. Pericardium, Heart, and Great Vessels in the Thorax". Skandalakis' surgical anatomy : the embryologic and anatomic basis of modern surgery. Athens, Greece: PMP. pp. section titled 'Pulmonary veins'. ISBN   9603990744.
  3. Bradley CJ, Haines DE (2020). "Pulsed field ablation for pulmonary vein isolation in the treatment of atrial fibrillation". Journal of Cardiovascular Electrophysiology . 31 (8): 2136–2147. doi:10.1111/jce.14414. PMID   32107812.
  4. 1 2 McGarry TJ, Narayan SM (2012). "The anatomical basis of pulmonary vein reconnection after ablation for atrial fibrillation: wounds that never felt a scar?". Journal of the American College of Cardiology . 50 (10): 939–941. doi:10.1016/j.jacc.2011.11.032. PMC   3393092 . PMID   22381430.
  5. Calkins H, Hindricks G, Yamane T (2018). "2017 HRS/EHRA/ECAS/APHRS/SOLAECE expert consensus statement on catheter and surgical ablation of atrial fibrillation". Europace . 20 (1): e1–e160. doi:10.1093/europace/eux274. PMC   5834122 . PMID   29016840.
  6. Eranki A, Wilson-Smith A, Manganas C (2023). "Mid term freedom from atrial fibrillation following hybrid ablation, a systematic review and meta analysis". Journal of Cardiothoracic Surgery . 18 (1): 155. doi: 10.1186/s13019-023-02189-2 . PMC   10114378 . PMID   37076929.
  7. 1 2 Ramirez FD, Reddy VY, Jaïs P (2020). "Emerging Technologies for Pulmonary Vein Isolation". Circulation Research . 127 (1): 170–183. doi:10.1161/CIRCRESAHA.120.316402. PMID   32716722.
  8. Darby AE (2016). "Recurrent Atrial Fibrillation After Catheter Ablation: Considerations For Repeat Ablation And Strategies To Optimize Success". Journal of Atrial Fibrillation. 9 (1): 1427. doi:10.4022/jafib.1427. PMC   5089515 . PMID   27909521.
  9. Porres, Diego Varona; Morenza, Óscar Persiva; Pallisa, Esther; Roque, Alberto; Andreu, Jorge; Martínez, Manel (July 2013). "Learning from the Pulmonary Veins". RadioGraphics. 33 (4): 999–1022. doi:10.1148/rg.334125043. ISSN   0271-5333. PMID   23842969.