Internal thoracic artery

{{Short description|Artery of the thorax}}

{{Infobox artery

| Name = Internal thoracic artery

| Latin = {{Lang|la|arteria thoracica interna, arteria mammaria interna}}

| Image2 = Gray522.png

| Caption2 = Right internal thoracic artery and its branches (labeled under its old name the Internal mammary artery, at upper right).

| BranchFrom = Subclavian artery

| BranchTo = Pericardiocophrenic
Anterior intercostal branches
Musculophrenic
Superior epigastric
Perforating branches

| Vein = Internal thoracic vein

| Supplies =

}}

The internal thoracic artery (ITA), also known as the internal mammary artery, is an artery that supplies the anterior chest wall and the breasts.{{Citation|last1=Kramer|first1=R. S.|title=Coronary Artery Bypass Grafting|date=2018-01-01|url=http://www.sciencedirect.com/science/article/pii/B9780128096574997540|encyclopedia=Encyclopedia of Cardiovascular Research and Medicine|pages=700–729|editor-last=Vasan|editor-first=Ramachandran S.|place=Oxford|publisher=Elsevier|language=en|doi=10.1016/b978-0-12-809657-4.99754-0|isbn=978-0-12-805154-2|access-date=2020-11-12|last2=Morton|first2=J. R.|last3=Groom|first3=R. C.|last4=Robaczewski|first4=D. L.|editor2-last=Sawyer|editor2-first=Douglas B.}} It is a paired artery, with one running along each side of the sternum, to continue after its bifurcation as the superior epigastric and musculophrenic arteries.

Structure

The internal thoracic artery arises from the anterior surface of the subclavian artery near its origin.{{Citation |last1=Stewart |first1=Charles E. |title=Chapter 18 - Deltopectoral flap |date=2009-01-01 |url=http://www.sciencedirect.com/science/article/pii/B9780721605197000186 |work=Flaps and Reconstructive Surgery |pages=193–205 |editor-last=Wei |editor-first=Fu-Chan |access-date=2020-11-12 |place=Edinburgh |publisher=W.B. Saunders |language=en |doi=10.1016/b978-0-7216-0519-7.00018-6 |isbn=978-0-7216-0519-7 |last2=Urken |first2=Mark L. |editor2-last=Mardini |editor2-first=Samir}}{{Citation|last1=Barral|first1=Jean-Pierre|title=13 - Vessels of the breast|date=2011-01-01|url=http://www.sciencedirect.com/science/article/pii/B9780702043512000132|work=Visceral Vascular Manipulations|pages=121–132|editor-last=Barral|editor-first=Jean-Pierre|place=Oxford|publisher=Churchill Livingstone|language=en|doi=10.1016/b978-0-7020-4351-2.00013-2|isbn=978-0-7020-4351-2|access-date=2020-11-12|last2=Croibier|first2=Alain|editor2-last=Croibier|editor2-first=Alain}} It has a width of between 1-2 mm.{{Citation|last1=Markiewicz|first1=Michael R.|title=43 - Local and Regional Flap Reconstruction of Maxillofacial Defects|date=2017-01-01|url=http://www.sciencedirect.com/science/article/pii/B9780702060564000447|work=Maxillofacial Surgery (Third Edition)|pages=616–635|editor-last=Brennan|editor-first=Peter A.|publisher=Churchill Livingstone|language=en|doi=10.1016/b978-0-7020-6056-4.00044-7|isbn=978-0-7020-6056-4|access-date=2020-11-12|last2=Ord|first2=Robert|last3=Fernandes|first3=Rui P.|editor2-last=Schliephake|editor2-first=Henning|editor3-last=Ghali|editor3-first=G. E.|editor4-last=Cascarini|editor4-first=Luke}}

It travels downward on the inside of the rib cage, approximately 1 cm from the sides of the sternum, and thus medial to the nipple. It is accompanied by the internal thoracic vein.

It runs deep to the abdominal external oblique muscle, but superficial to the vagus nerve.

In adults, the internal thoracic artery lies closest to the sternum at the first intercostal space. The gap between the artery and lateral border of the sternum increases when going downwards, up to 1.1 cm to 1.3 cm at the sixth intercostal space. In children, the gap ranges from 0.5 cm to 1.0 cm.{{cite journal |vauthors=Jelicić N, Djordjević L, Stosić T |title=Unutrasnji grudni krvni sudovi (a. et vv. thoracicae internae) i njihov prakticni znacaj |language=sr |trans-title=The internal thoracic blood vessels (internal thoracic arteries and veins) and their practical significance |journal=Srpski Arhiv Za Celokupno Lekarstvo |volume=124 |issue=3–4 |pages=58–61 |date=1996 |pmid=9102819 |doi= }}

=Branches=

After passing the sixth intercostal space, the internal thoracic artery splits into the following two terminal branches:

  • Musculophrenic artery{{Dash}}roughly follows the costal margin and it again gives branch for 7,8,9 ribs
  • Superior epigastric artery{{Dash}}continues the course of the internal thoracic artery, travelling downward into the abdominal wall and to the content of rectus sheath

Function

The internal thoracic artery supplies the chest wall and the breasts.

Clinical significance

=Use in bypass grafts=

The internal thoracic artery is the cardiac surgeon's blood vessel of choice for coronary artery bypass grafting. The left ITA has a superior long-term patency to saphenous vein grafts{{cite journal | last1 = Kitamura | first1 = S | last2 = Kawachi | first2 = K | last3 = Kawata | first3 = T | last4 = Kobayashi | first4 = S | last5 = Mizuguchi | first5 = K | last6 = Kameda | first6 = Y | last7 = Nishioka | first7 = H | last8 = Hamada | first8 = Y | last9 = Yoshida | first9 = Y | title = Ten-year survival and cardiac event-free rates in Japanese patients with the left anterior descending artery revascularized with internal thoracic artery or saphenous vein graft: a comparative study | journal = Nippon Geka Gakkai Zasshi | volume = 97 | issue = 3 | pages = 202–9 | year = 1996 | pmid = 8649330 }}{{cite journal | last1 = Arima | first1 = M | last2 = Kanoh | first2 = T | last3 = Suzuki | first3 = T | last4 = Kuremoto | first4 = K | last5 = Tanimoto | first5 = K | last6 = Oigawa | first6 = T | last7 = Matsuda | first7 = S | title = Serial angiographic follow-up beyond 10 years after coronary artery bypass grafting | journal = Circulation Journal | volume = 69 | issue = 8 | pages = 896–902 | year = 2005 | pmid = 16041156 | doi = 10.1253/circj.69.896 | doi-access = free }} and other arterial grafts{{cite journal |last1=Cohen |first1=G |last2=Tamariz |first2=MG |last3=Sever |first3=JY |last4=Liaghati |first4=N |last5=Guru |first5=V |last6=Christakis |first6=GT |last7=Bhatnagar |first7=G |last8=Cutrara |first8=C |last9=Abouzahr |first9=L |last10=Goldman |first10=Bernard S |last11=Fremes |first11=Stephen E |display-authors=8 |year=2001 |title=The radial artery versus the saphenous vein graft in contemporary CABG: a case-matched study |journal=The Annals of Thoracic Surgery |volume=71 |issue=1 |pages=180–5; discussion 185–6 |doi=10.1016/S0003-4975(00)02285-2 |pmid=11216742 |doi-access=free}} (e.g. radial artery, gastroepiploic artery) when grafted to the left anterior descending coronary artery, generally the most important vessel, clinically, to revascularize.

Plastic surgeons may use either the left or right internal thoracic arteries for autologous free flap reconstruction of the breast after mastectomy. Usually, a microvascular anastomosis is performed at the second intercostal space to the artery on which the free flap is based.

Additional images

File:Grant 1962 407.png|Anterior thoracic wall, from behind

File:Grant 1962 405.png|Diagram of an intercostal space

References

{{Reflist}}

=Figures of ITA grafts=

  • [https://web.archive.org/web/20130720091445/http://www.texheartsurgeons.com/Images/CADbypass.gif Figure of heart with two saphenous vein grafts (SVGs) and a LITA graft] - texheartsurgeons.com
  • [http://www.darcystudios.com/images/openingheart_28.jpg Drawing of the heart with a SVG to the right coronary artery (RCA) and a LITA graft to the LAD] {{Webarchive|url=https://web.archive.org/web/20211010070546/http://www.darcystudios.com/images/openingheart_28.jpg |date=2021-10-10 }} - D'Arcy Studios
  • [https://web.archive.org/web/20070928010512/https://www.mayoclinic.org/coronaryartery-jax/images/arterybypass.jpg Drawing of the heart with a SVG to the RCA and a LITA graft to the LAD] - Mayo Clinic

{{Arteries of chest}}

{{Authority control}}

Category:Arteries of the thorax