Operative Anatomy of the Heart

Bearbeitet von Denis Berdajs, Marko Turina

1st Edition. 2010. Buch. xv, 543 S. Hardcover ISBN 978 3 540 69227 0 Format (B x L): 21 x 27,7 cm Gewicht: 1597 g

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I Adachi); in this rare instance, the artery can be identified on the lat- eral edge of the scalenus anterior.

Fig. 3.1. Origin of the internal thoracic artery Brachial plexus Internal Subclavian artery Insertion of scalenus anterior thoracic artery Superior Ascending cervical artery cervical artery Suprascapular artery 3.1 Internal Thoracic Artery 111

Scalenus anterior Sternohyoid muscle Phrenic nerve Internal thoracic artery

Sternum

Internal Clavicle jugular vein

Vagus nerve Subclavian vein Phrenic nerve Subclavius Superficial cervical artery Cervical pleura

Ascending First Rib cervical artery

Brachial plexus Subclavian artery Insertion of scalenus anterior Transverse cervical artery Fig. 3.2. Origin of the internal thoracic artery, schematic drawing

In this case, the cervical internal thoracic artery traverses the first rib and enters the thoracic cavity in the first intercostal space.

Run off of the Internal Thoracic Artery Below the first costal cartilage, the artery descends just vertical to its Internal thoracic branching point. The artery is cov- artery ered by the intercostal cartilage and the internal intercostal muscle. It runsintheconnectivetissueofthe endothoracic fascia on the parietal Superior epigastric artery pleura, as far as the level of the third rib. Below this level, the artery is found upon the transversus thora- cis.Themostfrequentlevelofter- mination of the artery is the sixth intercostal space, where in 90% of cases it divides into two branches Fig. 3.3. Run-offofthe internal thoracic artery and in 10% of cases into three branches (Fig. 3.3). 112 3 Coronary Bypass Grafts

Table 3.1 Intercostal Adachi on 52 specimens (mm) Sandmann on Delorme Mignon Our data measured on 50 specimens (mm) space 40 specimens on 30 specimens Male Female (mm) (mm) Left Right I 8–9 (0–16) 8 11 6–20 6 (SD 3.9) 6.4 (SD 3.9) II 13 (8–19) 10 (6–15) 15.3 10–20 13.7 (SD 2.6) 13.9 (SD 2.7) III 12, 13, 14 (16–18) 11 (5–14) 15.6 10–21 14.5 (SD 3.1) 14.8 (SD 2.7) IV 12 (7–16) 10 (6–15) 15.4 8–25 14 (SD 3.6) 14.6 (SD 3.1) V 16.3 (SD 1.7) 16.8 (SD 2.5)

Sternal insertion of Manubrium of sternum pectoralis major Transversus thoracis Endothoracic fascia

I II III IV

Fig. 3.4. Relation between the internal tho- racic artery and the sternum External intercostal muscle Internal thoracic artery/vein Internal intercostal muscle

According to our measurements, the artery runs ap- the transversus thoracis and is lateral to the vein. Note proximately 13 mm lateral from the sternal edge. that in the second intercostal space lateral to the vein, a Figure 3.4 shows a superior view of the relationship retrosternal lymphoid gland has been left in situ. A between the lateral sternal edge and the run off of the comparisonofthedistancebetweentheleftandright internal thoracic artery. The intercostal muscles have arteries revealed no significant deviations (Table 3.1). been removed; one can see that the artery runs superfi- The minimal distance was measured at the first inter- cial to the endothoracic fascia. The transversus thoracis costal space. From the second to the fourth intercostal was left in situ. Initially, the artery is medial to the con- space, the distance between the artery and the sternal joined vein (first and second intercostal spaces), then line remains approximately constant. We noted increase just behind the third rib the vein crosses the artery and in this distance at the level of the sixth intercostal space travels more medially. This is particularly obvious in (Fig. 3.4). the third intercostal space. Here, the artery runs along 3.1 Internal Thoracic Artery 113

5 5 5 6 6 6 4 4 4 7 7 11 7 11 1 11 3 1 3 8 1 8 3

8 9 9 9 2 2 10 2 10 10 a b c

5 5 5 6 6 6 7 4 8 4 7 11 11 7 11 1 3 1 8 3 1 8 4

9 9 9 10 2 2 10 10 2 d e f

5 4 6 5 4 6 11 1. Vertebral artery 2. Internal thoracic artery 7 11 1 1 3. Thyrocervical trunk 7 8 3 3 4. Inferior thyroid artery 5. Ascending cervical artery 8 6. Superficial cervical artery 9 7. Suprascapular artery 8. Transverse cervical artery 2 9 2 9. Costocervical trunk 10 10. Supreme intercostal artery 11. Deep cervical artery g 10 h Fig. 3.5. Variants of the origin of the internal thoracic artery

Morphological variants of the origin of the internal tho- ers likewise together (Fig. 3.5b). In the third variant racic artery cannot be discussed without emphasizing (8.3%), the internal thoracic artery and the suprascapu- its relationships with the vertebral artery, and the costo- lar artery share a common origin (Fig. 3.5c). In the cervical and thyrocervical trunks. Adachi’s classifica- fourth variant (4.1%), the transverse cervical artery tion scheme distinguishes several frequently occurring originates separately and the other arteries branch off anatomical types with respect to origin from the sub- together (Fig. 3.5d). All of the vessels may arise from a clavian artery. In the most common (normal) type common trunk (3.3%; Fig. 3.5e). The internal thoracic, (45.5%), the vertebral and the internal thoracic arteries, suprascapular, and transverse cervical arteries can arise and the costocervical and thyrocervical trunks arise as separately, the others having a common origin (3.3%; separate branches (Fig. 3.5a). In the second variant Fig. 3.5f). The internal thoracic and the inferior thyroid (19%), the internal thoracic artery and the transverse arteries can have separate origins, with the others aris- cervical artery arise from a common trunk, and the oth- ing together (3.3%; Fig. 3.5g).Thetransversecervical