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Venous thoracic outflow syndrome may occur as a result from compression of the subclavian and/or axillary vein and consequently, decreased blood flow and increased risk of thrombus formation. A previously healthy 34-year-old woman who, after intensive crossfit training, experienced sudden intense pain and swelling in her right upper arm was referred for computed tomography of her right upper arm and thoracic veins. The computed tomography was performed using bilateral injection of low dose, diluted contrast medium. The computed tomography venography revealed an elongated contrast medium embraced thrombus in the right subclavian and axillary vein. By using a dual injection consisting of diluted contrast medium, artifact-free visualization of arm veins and sufficient enhancement of thoracic veins can be achieved. Keywords: Ct, Contrast agents-intravenous, Upper extremities, Computed tomography venography

Introduction The axillary and cephalic veins are used for various clinical purposes but their anatomy is not fully understood. Increased knowledge and information about them as well as superficial veins in the upper arm would be useful. Objective The aim of this study is to contribute to the literature regarding the anatomy of the venous drainage of the upper extremity. Methods The veins of forty upper extremities from twenty one adult cadavers were injected and their axillary regions dissected. The course and pattern of drainage of the venous tributaries in the axillary region were identified and recorded. Results The basilic, brachial, subscapular, lateral thoracic and superior thoracic veins drained mainly into the axillary vein, in common with most textbook descriptions. However, the thoracoacromial veins were observed to drain into the cephalic vein in 70.0% of upper limbs. In addition, a venous channel connecting the distal part and proximal part of the axilla was found along the posterolateral wall of the axilla in 77.5% of the upper limbs. In 95.0% of upper limbs, we discovered a superficial vein which ran from the axillary base and drained directly into the axillary vein. Conclusion The veins from the inferomedial part of the axilla drain into the axillary vein, whereas the veins from the superolateral part of the axilla drain into the cephalic vein. The venous drainage of the axilla is variable and in common with venous drainage elsewhere, does not necessarily follow the pattern of the arterial supply.

Background Accurate anatomical landmarks to locate the thoracodorsal nerve are important in axillary clearance surgery. Methods Twenty axillary dissections were carried out on ten preserved Sri Lankan cadavers. Cadavers were positioned dorsal decubitus with upper limbs abducted to 900. An incision was made in the upper part of the anterior axillary line. The lateral thoracic vein was identified and traced bi-directionally. The anatomical location of the thoracodorsal nerve was studied in relation to the lateral border of pectoralis minor and from a point along the lateral thoracic vein, 2 cm inferior to its confluence with the axillary vein. Results The lateral thoracic vein was invariably present in all the specimens. All the lateral thoracic veins passed lateral to the lateral border of pectoralis minor except in one specimen, where the lateral thoracic vein passed along its lateral border. The thoracodorsal nerve was consistently present posterolateral to the lateral thoracic vein. The mean distance to the lateral thoracic vein from the lateral border of pectoralis minor was 28.7 ± 12.6 mm. The mean horizontal distance, depth, and displacement, from a point along the lateral thoracic vein, 2 cm inferior to its confluence with the axillary vein to the thoracodorsal nerve were 14.5 ± 8.9 mm, 19.7 ± 7.3 mm and 25 ± 5 mm respectively. The thoracodorsal nerve was found in a posterolateral direction, at a 540 ± 120 angle to the horizontal plane, 95% of the time. Conclusions The lateral thoracic vein is an accurate guide to the thoracodorsal nerve. We recommend exploring for the thoracodorsal nerve from a point 2 cm from the confluence of the lateral thoracic vein and the axillary vein for a distance of 25 ± 5 mm in a posterolateral direction, at a 540 ± 120 angle to the horizontal plane.

Thoracic veins congenital abnormalities are important uncommon developmental anomalies that have a wide range of presentation from isolated incidental findings to a part of more complex anomalies. It can be categorized into systemic venous system and pulmonary venous system. It is of important value to understand the mediastinal vascular anatomy to help to identify variable vascular anomalies. In this study we attempt to describe some incidentally encountered mediastinal large venous anatomical variants in patients undergoing MDCT chest in order to avoid further unnecessary studies.

Introduction. Persistent left superior vena cava is the most common thoracic venous abnormality which is usually asymptomatic, found incidentally during pacemaker implantation. The main problem is related to reaching the appropriate pacing site and ensuring stable lead placement. Case report. We reported a successful implantation of a biventricular pacing and defibrillator device (CRT-D) via a persistent left superior vena cava in a 55-year-old man with dilated cardiomyopathy and severe heart failure. A persistent left superior vena cava was detected during CRT-D implantation. We managed to position electrodes in the right ventricular outflow tract, a posterior branch of the coronary sinus and in the right atrium. Conclusion. Congenital anomalies of thoracic veins may complicate lead placement on the appropriate and stable position. The presented case demonstrates a successful biventricular pacing and defibrillator therapy device implantation in a patient with dilated cardiomyopathy and severe heart failure.

The study has analysed the action of histamine in the rabbit venous system and evaluated its potential role in contraction during increased venous pressure. We have found that a great variety exists in histamine sensitivity and H(1) -histamine receptor expression in various types of rabbit veins. Veins of the extremities (saphenous vein, femoral vein, axillary vein) and abdomen (common iliac vein, inferior vena cava) responded to histamine by a prominent, concentration-dependent force generation, whereas great thoracic veins (subclavian vein, superior vena cavas, intrathoracic part of inferior vena cava) and a pelvic vein (external iliac vein) exhibited slight sensitivity to exogenous histamine. The lack of reactivity to histamine was not due to increased activity of nitric oxide synthase (NOS) or heme oxygenase-1. H(1) -histamine receptor expression of veins correlated well with the histamine-induced contractions. Voltage-dependent calcium channels mediated mainly the histamine-induced force generation of saphenous vein, whereas it did not act in the inferior vena cava. In contrast, the receptor-operated channels were not involved in this response in either vein. Tyrosine phosphorylation occurred markedly in response to histamine in the saphenous vein, but not in the inferior vena cava. Histamine induced a prominent ρ kinase activation in both vessels. Protein kinase C and mitogen-activated protein kinase (MAPK) were not implicated in the histamine-induced intracellular calcium sensitization. Importantly, transient clamping of the femoral vein in animals caused a short-term constriction, which was inhibited by H(1) -histamine receptor antagonist in vivo. Furthermore, a significantly greater histamine immunopositivity was detected in veins after stretching compared to the resting state. We conclude that histamine receptor density adapts to the actual requirements of the circulation, and histamine liberated by the venous wall during increased venous pressure contributes to the contraction of vessels, providing a force for the venous return.

Ectopic activity in cardiac muscle within pulmonary veins (PVs) is associated with the onset and the maintenance of atrial fibrillation in humans. The mechanism underlying this ectopic activity is unknown. Here we investigate automatic activity generated by catecholaminergic stimulation in the rat PV. Intracellular microelectrodes were used to record electrical activity in isolated strips of rat PV and left atrium (LA). The resting cardiac muscle membrane potential was lower in PV [−70 ± 1 (SE) mV, n = 8] than in LA (−85 ± 1 mV, n = 8). No spontaneous activity was recorded in PV or LA under basal conditions. Norepinephrine (10−5 M) induced first a hyperpolarization (−8 ± 1 mV in PV, −3 ± 1 mV in LA, n = 8 for both) then a slowly developing depolarization (+21 ± 2 mV after 15 min in PV, +1 ± 2 mV in LA) of the resting membrane potential. Automatic activity occurred only in PV; it was triggered at approximately −50 mV, and it occurred as repetitive bursts of slow action potentials. The diastolic membrane potential increased during a burst and slowly depolarized between bursts. Automatic activity in the PV was blocked by either atenolol or prazosine, and it could be generated with a mixture of cirazoline and isoprenaline. In both tissues, cirazoline (10−6 M) induced a depolarization (+37 ± 2 mV in PV, n = 5; +5 ± 1 mV in LA, n = 5), and isoprenaline (10−7 M) evoked a hyperpolarization (−11 ± 3 mV in PV, n = 7; −3 ± 1 mV in LA, n = 6). The differences in membrane potential and reaction to adrenergic stimulation lead to automatic electrical activity occurring specifically in cardiac muscle in the PV.

Background and purpose: Our case report deals with the importance of detailed echocardiographic examination for differential diagnosis of coronary sinus dilation and development of abnormalities of great thoracic veins. Case presentation: A 49-year-old man underwent transthoracic echocardiography for atypical chest pain. A dilated coronary sinus was found and venous contrast echocardiography raised the suspicion of absent right and persistent left superior vena cava. Transesophageal echocardiography showed absence of right superior vena cava. The echocardiographic findings were confirmed by upper venous digital subtraction cavography. Conclusion: combination of agenesia of right SVC and isolated persistent left SVC in adult patients is a very rare abnormality. Both clinicians and sonographers should be alerted to the possible presence of this combined venous anomaly. Transthoracic echocardiograpy – including agitated saline infusion to the antecubital vein – is an important diagnostic tool for accurate diagnosis of this congenital thoracic venous malformation.

ObjectivesThis study sought to investigate the regional frequency distribution from multiple bi-atrial sites in different types of paroxysmal atrial fibrillation (AF).BackgroundA previous study showed a left atrium (LA) to right atrium (RA) frequency gradient in patients with paroxysmal AF.MethodsForty-four patients (age = 60 ± 16, male patients = 27) with paroxysmal AF originating from the pulmonary veins (PVs) (n = 31) or superior vena cava (SVC) (n = 13) were included. Frequency analysis was performed on the intracardiac electrograms (7 s, 1 kHz/channel) recorded from PV, posterior LA, coronary sinus (CS), posterolateral RA, and SVC. The largest peak frequency was identified as the dominant frequency (DF).ResultsIn the PV-AF patients, there was a frequency gradient from the PV ostium to the LA, RA, and SVC (8.5 ± 3.3 Hz vs. 5.9 ± 1.1 Hz vs. 5.2 ± 0.85 Hz vs. 5.5 ± 0.48 Hz, respectively, p < 0.001). The highest DFs were mostly located at the arrhythmogenic PV ostium (58%). The DFs of the arrhythmogenic PV and PV ostium were significantly higher than those of the non-arrhythmogenic PVs and PV ostia (p < 0.05). In the SVC-AF patients, there was a frequency gradient from the SVC to the RA, LA, and PV (8.0 ± 2.4 Hz vs. 5.9 ± 1.1 Hz vs. 5.9 ± 0.7 Hz vs. 5.8 ± 0.7 Hz, respectively, p = 0.001). The highest DFs were mostly located inside the SVC (77%) instead of the SVC ostium (as compared with PV-AF patients, p = 0.035).ConclusionsThe location of the highest DF depended on the arrhythmogenic PV or SVC. A frequency gradient was present between the arrhythmogenic thoracic vein and atrium in all patients.

puted tomographic scanning usually suggests the diagnosis of cystic lesions. Opacification of the thoracic collateral veins can be very difficult to obtain, and it depends on the amount of contrast material, the injection rate, and the timing of the administration. In the present case the site and density of the mass were consistent with the diagnosis of a pleuropericardial cyst. The possibility of a mediastinal varix was not considered for the absence of other varicose abnormalities and the absence of clinically evident portal hypertension. The possibility of a membranous obstruction of the inferior vena cava was considered after surgical exploration and confirmed by means of echocardiographic Doppler examination. The site of this rare abnormality was atypical. Of the 4 cases of paracardiac mass caused by mediastinal varices reported by Chung and colleagues, all were on the left side, and the pattern of drainage was from the hepatic veins through the left inferior phrenic vein to the left pericardiophrenic vein. In the presented case, on the basis of surgical exploration, it was reasonable to assume that the drainage was from the right inferior phrenic vein through the right pericardiophrenic vein into the right thoracic vein. This observation suggests that isolated varicose abnormality of the pericardiophrenic vein should be considered in the differential diagnosis of mediastinal plurilobate masses. In this case a different timing in image uptake after contrast injection could support such a diagnosis and justify magnetic resonance, venocavography, or both, to avoid invasive diagnostic procedures such as videoassisted thoracoscopy.