E-mail address: Jean. Deslauriers fmed. Occasionally the right superior Coronary veins entering the coronary sinus in intercostal vein integrating the first to fourth inter- the right atrium costal veins drains to it directly instead of to the Coronary venous return to the right and left azygos system.
The inferior thyroid vein also ventricle via the thebesian veins enters it medially. Bronchial venous drainage distal to third generation of bronchial tree entering the Left Brachiocephalic Vein pulmonary venous system to the left atrium This structure is longer than its contralateral equiv- alent and runs for about 6 cm in length beginning behind the sternal end of the left clavicle and pro- superior intercostal vein. On rare occasion, this gressing obliquely downward and to the right vein may be patent and pose a hazard during intra- behind the manubrium sterni of the right first costal pericardial left pneumonectomy.
It descends costal vein draining the upper 3 or 4 intercostal for 2 to 3 cm to the point where the pleura, right spaces as well as a variable number of inferior phrenic nerve, and internal thoracic artery and thymic veins entering its superior aspect. Pericar- vein form its lateral relationship. The thymus gland dial tributaries also interface with this structure. This vessel joins the left brachiocephalic vein Superior Vena Cava at the level of the lower border of the first right costal From the junction of the 2 brachiochephalic veins, cartilage to become the superior vena cava.
Its distal portion is enveloped by the pericardium. The phrenic Table 2 Points of interest nerve has a direct lateral relationship to this struc- ture and its medial relationships include the The space between the posterior wall of the innominate artery and the ascending aorta.
The superior vena cava and the anterior right final tributary to the superior vena cava near its main pulmonary artery must be free to allow termination is the azygos vein passing over the proximal control of the latter structure upper aspect of the right main stem bronchus during a right pneumonectomy. The vestigial vein of Marshall may be patent in This structure originates from calescence of the the pericardial fold over the left right subcostal and intercostal veins on the right intrapericardial pulmonary artery mandating and the hemiazygos vein, which pass from the control during an intrapericardial left left anterior to the spinal column.
Several esopha- pneumonectomy. The tissue plane between Intraoperative detection of a venous the posterior wall of the distal superior vena cava abnormality should alert the surgeon to the and the anterior wall of the right main pulmonary probability that other anomalies of the artery is referred to surgically as the retro caval systemic and pulmonary circulation and the bronchial tree may be encountered during space of Allison and is of particular significance a thoracic surgical procedure.
Superior Vena Cava and Brachiocephalic Veins Internal jugular vein Left brachiocephalic vein External jugular vein Left subclavian vein Highest Right intercostal brachiocephalic vein vein Ligament of the Superior left vena cava vena cava Coronary sinus Oblique vein of the left atrium oblique vein of Marshall Accessory Azygos vein hemiazygos vein Intercostal veins Hemiazygos Inferior vein vena cava Fig.
Formation of the systemic venous system in the embryo. As a result, the left brachiocephalic vein does not form. Abnormal pulmonary venous return is also possible and would potentially result in the pulmonary veins draining into the superior vena cava.
Obstructions of the superior vena cava via mediastinal mass or thrombus may require surgical correction. Trauma to the thoracic region, damage from long-term central line catheterization, or damage from chronic use of pacing electrodes can also result in a need for surgical repair of the superior vena cava.
Great care is necessary when clamping off the superior vena cava for surgical repair as venous return from the head and neck will be impaired under these circumstances, and such impairment could potentially lead to poor patient outcomes. Complete or partial obstruction of the superior vena cava can occur, resulting in a condition known as superior vena cava syndrome.
Causes of the obstruction may include intrinsic stenosis, extrinsic compression, or thrombosis of the vein. Malignancy is the single most common cause with cancer of the lung, lymphoma, or metastatic cancers resulting in the majority of superior vena cava obstructions. The clinical presentation of superior vena cava syndrome may vary widely and depends on a variety of factors including the severity, speed, and location of the obstruction. Patients with a slowly developing obstruction may show few or no symptoms.
These patients may develop collateral channels for blood flow to restore their venous return. The location of these collateral channels depends upon the location of the blockage. If the obstruction occurs in the area of the superior vena cava located before the azygos vein, the right superior intercostal veins will serve as the primary collateral pathway for azygos vein drainage. This pathway is often the most asymptomatic. If the obstruction occurs at the azygos vein, collateral channels will form between the superior vena cava and inferior vena cava via the internal mammary veins, superior and inferior epigastric veins, and the iliac vein.
If the obstruction occurs past the point at which the azygos vein drains into the superior vena cava the blood will move via channels from the azygos and hemiazygos veins into the ascending lumbar and lumbar veins which will drain into the inferior vena cava and allow return into the right atrium. When this large-bore vein suffers more acute obstruction, it can result in upstream effects causing tributary veins in the head and neck to appear enlarged. It can also result in clinical symptomology that may include shortness of breath, cough, angina, facial flushing, headache, bilateral upper extremity swelling, and dysphagia.
Patients with an obstructed superior vena cava may have a positive Pemberton sign. Treatment of the obstruction depends on the cause. In the context of cancer, chemotherapy, or radiation are options. In the event of a thrombus, anticoagulation may be indicated to prevent further clot formation.
Stent placement is considered a first-line treatment option. CT is the imaging modality of choice for diagnosis of a superior vena cava obstruction. Plain radiographs may also be used to detect indirect signs of a mediastinal mass, but are not ideal. This book is distributed under the terms of the Creative Commons Attribution 4. StatPearls [Internet]. Affiliations 1 Alabama College of Osteopathic Medicine. Introduction The superior vena cava is a large, significant vein responsible for returning deoxygenated blood collected from the body back into the heart.
Structure and Function The right and left brachiocephalic veins, also known as the innominate veins, join to form the superior vena cava posterior to the inferior border of the first right costal cartilage. Embryology The superior vena cava derives from the proximal portion of the right anterior cardinal vein and the right common cardinal vein at a point that is caudal to the transverse anastomosis in the embryo.
Blood Supply and Lymphatics The right and left brachiocephalic, or innominate, veins converge to form the superior vena cava at the level of the right first costal cartilage. Nerves Sympathetic axons originating from the right stellate ganglion descend along the superior vena cava. Muscles As with other arteries and veins, the superior vena cava is made up of three total layers of muscle. Physiologic Variants One physiological variation that can occur is known as left superior vena cava.
Surgical Considerations Obstructions of the superior vena cava via mediastinal mass or thrombus may require surgical correction. Clinical Significance Complete or partial obstruction of the superior vena cava can occur, resulting in a condition known as superior vena cava syndrome.
Se desconoce la causa exacta de los sarcomas, incluidos los leiomiosarcomas. El tumor puede crecer y diseminarse sin signos aparentes. La trombosis de la vena cava inferior VCI es una entidad poco reconocida que se asocia con una morbilidad y mortalidad significativa a corto y largo plazo.
Por lo tanto, el cribado de todos los pacientes con TVP para la trombosis de VCI puede ser tedioso, de bajo rendimiento y poco rentable. Estas condiciones incluyen:. La principal diferencia entre la aorta y la vena cava es que la aorta lleva sangre oxigenada mientras que la vena cava lleva sangre desoxigenada. Suministra sangre oxigenada en todo el cuerpo. Son la vena cava superior y la vena cava inferior. La vena cava superior drena la sangre desoxigenada de la cabeza, los brazos y otras partes superiores del cuerpo, mientras que la vena cava inferior drena la de las partes inferiores del cuerpo.
El tumor se extrae y la vena cava se cierra. Ocasionalmente se requiere un bypass venoso o incluso un bypass cardiopulmonar completo para realizar estos procedimientos de manera segura.
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