Bilateral variation in the branching pattern of the subclavian artery: an unusual finding with clinical implications / Variação bilateral no padrão de ramificação da artéria subclávia: um achado incomum com implicações clínicas

Abstract The subclavian artery is a significant branch of the aortic arch. We present a rare case of a bilateral variation in the branching pattern of the subclavian artery, observed in an adult male cadaver aged 70 years. On both the sides of the neck, all the branches of the subclavian artery took their origin from its first part. There was a rare occurrence of a cervicodorsoscapular trunk, which gave rise to superficial cervical, suprascapular, and dorsal scapular arteries. The same branching pattern was observed on the left side of the neck, with the presence of another cervicodorsoscapular trunk. Thyrocervical trunk and transverse cervical artery were both absent from the cervical region bilaterally. The inferior thyroid artery was a direct branch from the subclavian artery. Knowledge regarding variations of the subclavian artery is very important as lateral cervical region arteries are important for flap harvesting in plastic and reconstruction surgery. Preoperative radiologic evaluation of pedicles might help in choosing the optimal flap design, prevent ischemic complications, and help to improve overall treatment outcomes.

Resumo A artéria subclávia é um ramo significativo do arco da aorta. Apresentamos um caso raro de variação bilateral do padrão de ramificação da artéria subclávia, observada em um cadáver adulto do sexo masculino de 70 anos. Em ambos os lados do pescoço, todos os ramos da artéria subclávia originavam-se de sua primeira parte. Houve rara ocorrência de tronco escapular cervical dorsal, que deu origem às artérias cervical superficial, supraescapular e escapular dorsal. O mesmo padrão de ramificação foi observado no lado esquerdo do pescoço, com a presença de tronco escapular cervical dorsal. O tronco tireocervical e a artéria cervical transversa estavam ausentes em ambas as regiões cervicais direita e esquerda. A artéria tireóidea inferior consistia em um ramo direto da artéria subclávia. O conhecimento das variações da artéria subclávia é fundamental, pois as artérias da região cervical lateral são importantes para a obtenção de retalhos em cirurgias plásticas e reconstrutivas. A avaliação radiológica pré-operatória dos pedículos pode ajudar na escolha do desenho ideal do retalho, prevenir complicações isquêmicas e ajudar a melhorar o resultado geral do tratamento.

Variant Anatomy Of Internal Thoracic Artery- Clinical Implications

Background: Now a days, Internal thoracic artery (ItA) is being widely used in coronary artery bypass grafting(CABG) and in breast reconstructive surgeries. In addition, the area around its origin is also used for subclavianvein catheterization and introducing a pacemaker.Aim: Aim of the study was to know the normal and variant anatomy of internal thoracic artery in Indian subjectsin order to provide useful data to thoracic surgeons, so as to prevent iatrogenic complications in ItA dissections.Clinical applications related to variations were analysed.Material and Methods: 30 cadavers were dissected to see the mode of origin of internal thoracic artery, diameterat its origin and relation with phrenic nerve and thyrocervical trunk.Results: 55 arteries were showing normal origin and tend to arise opposite the root of thyrocervical trunk.Remaining 5 were arising in common with one or two branches of thyrocervical trunk. Average diameter at itsorigin was 2.8cm on left and 2.6cm on right. Relation with phrenic nerve was variable.Conclusion: During CABG surgery, Breast reconstructive surgery and various interventional procedures, it isimportant to know the variant pattern of ItA so as to avoid iatrogenic complications

Scalenus Anterior Muscle With Two Heads Associated With Variation In The Branches Of Subclavian Artery: A Rare Presentation

Arterial variations are quite common. Many studies had elaborated variations in branching pattern of subclavianartery. Present study illustrates a unique feature of scalenus anterior muscle having two heads of origin and acommon trunk for internal thoracic artery (ITA) and thyrocervical trunk (TCT). This rare common trunk passesbetween two heads of right scalenus anterior. Such rare variation was not reported so far. The rarity of suchvariation signifies the necessity of the present study. On the left side all branches arose normally from subclavianartery except dorsal scapular artery which originates from second part itself instead of third part which is aquite common variation. The Internal thoracic artery is widely utilized as a great conduit for MyocardialRevascularization. This common truncal origin is of great surgical importance to Cardiothoracic Surgeons,Cardiovascular Surgeons and Interventional Therapy Radiologists.