F.P. Weber syndrome associated with a brachial artery aneurysm. A case report

Klippel-Trenaunay syndrome is characterized by the triad of unilateral port-wine hemangiomas, varicose veins, and hypertrophy of bone and soft tissue affecting one or more limbs. The rare F.P. Weber syndrome describes the mentioned entity and additional arteriovenous malformations. The association of an arterial aneurysm with the F.P. Weber syndrome has never been described in the current literature. A case of a brachial artery aneurysm in a patient with F.P. Weber syndrome is presented and the etiology of arterial aneurysm combined with congenital vascular abnormalities is discussed.

Brachioradialis muscle flap: clinical anatomy and use in soft-tissue reconstruction of the elbow

A detailed gross anatomical dissection of 53 upper extremities was performed to define the muscular and vascular anatomy of the brachioradialis muscle and to evaluate its arc of rotation with specific examination of its usefulness in covering soft-tissue defects of the elbow region. A consistent vascular anatomy was delineated, with a major pedicle found each time near the elbow arising (in descending order of frequency) from the radial recurrent, radial, and brachial arteries. A variable number of minor pedicles were found throughout the muscle's length. Pedicled proximally, the distal muscle could cover the elbow both anteriorly and posteriorly in each case; the proximal portion of the muscle (distally pedicled flap) could cover the anterior elbow consistently (100%) as well as the posterior elbow (in 91% of dissections). The muscle's arc of rotation encompasses the distal half of the arm and the proximal two thirds of the forearm, with a consistent ability to cover defects of up to 3 cm in the elbow region. Our studies confirm a consistent and robust vascular anatomy as well as an arc of rotation that allows predictable coverage of elbow defects in a one-stage procedure with minimal morbidity, no loss of upper extremity function, and no need to sacrifice the major vessels of the upper extremity.

Multiple aneurysms and aortic dissection: an unusual manifestation of Marfan's syndrome

Annuloaortic ectasia and dissection of the ascending aorta are common cardiovascular complications of Marfan's syndrome. True aneurysms of the subclavian arteries in these patients are rare. We present an unusual case of a 37-year-old woman who over the span of 10 years sequentially developed an aneurysm of the ascending aorta (annuloaortic ectasia), a right subclavian artery aneurysm, a left axillary-subclavian artery aneurysm, and a dissection of the aortic arch. Aside from the aortic dissection, the aneurysms produced no symptoms. All vascular complications were detected with computed tomography and managed successfully. This case emphasizes the need for close postoperative surveillance in patients with Marfan's syndrome who have had one cardiovascular complication of the disease.

An anomalous muscle in the distal half of the arm

During dissection an anomalous muscle was found on the medial aspect in the distal half of one left upper extremity. This muscle arose from the humerus between the m. coracobrachialis and the m. brachialis, passed obliquely across the front of the brachial artery and median nerve and blended with the common origin of the forearm flexor muscles. It does not appear to be an additional head of the biceps brachii or the brachialis muscles. The existence of this anomalous muscle should be kept in mind in a patient presenting with a high median nerve palsy together with symptoms of brachial artery compression.

Platelet aggregation and in vivo shear forces

Haemodynamic shear forces have been reported to exert direct and indirect effects on platelet reactivity. In vitro, they activate platelets leading to spontaneous or facilitated aggregation. In vivo, they stimulate the production of endothelium-derived anti-aggregatory agents. This study was designed to evaluate in hypertensive patients, before and after antihypertensive treatment, the possible role of these haemodynamic forces, determined at the brachial artery level on the ex vivo platelet aggregatory response to ADP and collagen. Platelet reactivity, evaluated by EC50 for ADP and collagen, was found to be related to blood velocity, shear rate and shear stress (p < 0.01 for each). These inverse correlations of platelet aggregation with stress levels did not depend on age, body mass index, mean blood pressure, serum cholesterol and triglycerides or haematocrit. They were also independent of platelet cytosolic Ca2+ and cyclic AMP. The changes in shear forces and in aggregatory responses to ADP and collagen induced by nitrendipine treatment for 6 months remained negatively correlated, confirming the relationships existing between haemodynamic shear forces and platelet reactivity. These results indicate that the shear antiaggregant effects, likely mediated by flow-dependent endothelium-derived factors, prevail over its direct platelet aggregating effects.

Bilateral brachial artery fibromuscular dysplasia

Fibromuscular dysplasia is a nonatherosclerotic, noninflammatory vascular disease that usually involves medium- and small-sized arteries. It is most commonly observed in the renal, carotid, and intracerebral arteries, although it has been reported in other arterial beds. The most common form is characterized by medial fibrosis, with or without smooth muscle cell hyperplasia, which can result in luminal narrowing and turbulent flow. There is often a secondary aneurysmal degeneration of the artery, which may or may not be associated with thrombosis or obstruction of flow. This accounts for the typical "string-of-beads" appearance seen on arteriography. We describe a patient who presented with ischemia of the right hand secondary to fibromuscular dysplasia of the brachial artery. Subsequent studies also demonstrated fibromuscular dysplasia in the other brachial artery as well as mild involvement of the right renal artery. The patient was treated on the symptomatic side with dilatation of proximal lesions, resection of the thrombosed segment, and reconstruction with a reversed saphenous vein graft. Distal pulses were fully restored postoperatively. Pathologic examination confirmed the arteriographic and clinical diagnosis of fibromuscular dysplasia. The salient features of this case are reviewed in addition to the other cases reported in the literature.

Structural and dynamic changes in the elastic arteries due to arterial hypertension and hypercholesterolemia

Five groups of 20 patients each were studied to analyze the vascular dynamics and structure of the elastic arteries. Group I consisted of healthy young individuals (27 +/- 4 years); Group II of healthy adults (46 +/- 9 years); Group III of normotensive hypercholesterolemic adults (45 +/- 12 years and serum cholesterol > 239 mg/dl); Group IV of hypertensive normocholesterolemic adults (56 +/- 13 years); and Group V of hypertensive hypercholesterolemic adults (56 +/- 9 years). The differential arterial pressure was estimated and divided by the volume change (delta P/delta V) of the aorta and the carotid and brachial arteries. The volume change was calculated using the "cylinder formula", measuring the radius from the ultrasonographic vessel image and assigning the cylinder a height of 1 cm. The A/E index of the Doppler transmitral spectrum and the maximum velocity flow using Doppler in the above arteries were calculated. The presence of carotid atherosclerosis was observed and given an arbitrary scoring grade of 0, 1, or 2. A higher arterial and ventricular stiffness was found in the hypertensive patients regardless of the presence of hypercholesterolemia. A higher fall in Doppler velocity and an increase in atherosclerosis lesions were found in Group V. Based on the results of this study, it was concluded that vascular and left ventricular stiffness have a close relationship with arterial hypertension but not with hypercholesterolemia. The hypercholesterolemic patients had a higher prevalence of carotid atherosclerosis and a higher scoring grade of severity.

Myxomatosic aneurysm of a brachial artery in a child

We present a case of an aneurysm in a brachial artery of a 4.5-year-old child which was resected with the interposition of a venous graft. Histological examination of the aneurysm showed a myxomatous damage to the wall of the vessel. Examination of the cardiovascular system did not reveal a myxoma of the heart. The available literature was searched for a similar description of an isolated aneurysm of a peripheral artery but none was found.

[Acute arterial occlusion of the upper extremity by tumor embolism]

We present a case of acute occlusion of the right branchial artery in a 56-year-old male caused by bronchogenic tumor embolus as the first manifestation of malignancy. The primary tumor was shown to be inoperable and rapidly formed metastases in skin and liver. The case presented demonstrates, that embolic events originating from malignant tumor cells are characteristic for organ-exceeding tumor growth. Thus the prognosis is generally poor.

Comparative effects of diabetes mellitus and hypertension on physical properties of human large arteries

OBJECTIVES

The effects of hypertension and diabetes on the physical properties of large arteries were compared in men.

BACKGROUND

Although these two diseases are linked to vascular stiffening, no study has analyzed whether the arterial rigidity in diabetes is as substantial as in hypertension.

METHODS

Noninvasive measurements of brachial artery mean pressure, diameter (pulsed Doppler study) and compliance (pulse wave velocity) were obtained in 29 men: 11 control subjects, 9 hypertensive nondiabetic patients and 9 diabetic normotensive patients. Individual diameter- and compliance-pressure curves extrapolated from the measured diameter and mean pressure point with a logarithmic elastic model permitted calculation of isobaric diameter and compliance at the same pressure in each subject.

RESULTS

Compared with control subjects, hypertensive patients had a larger brachial artery measured diameter and isobaric diameter (p < 0.01) and lower measured and isobaric compliance (p < 0.001, p < 0.01). Compared with control subjects, diabetic patients had lower measured and isobaric compliance (p < 0.01). Comparison of diabetic and hypertensive patients showed that measured diameter and isobaric diameter were decreased in the former (p < 0.01). In the control and hypertensive groups, mean pressure correlated positively with measured diameter and isobaric diameter (p < 0.01) and negatively with measured and isobaric compliance (p < 0.001 and p < 0.01, respectively). In the control and diabetic groups, fasting glucose correlated negatively with measured and isobaric compliance (p < 0.01, p < 0.05).

CONCLUSIONS

Intrinsic alterations of the large artery independent of a stretching pressure effect reduce arterial elasticity similarly in those with hypertension or diabetes. The loss of compliance is related to the chronic elevation of blood pressure in hypertension and to that of glycemia in diabetes and is associated with a relative large artery vasoconstriction in diabetic patients as compared with patients with hypertension.

The effect of hypertension and ACE inhibition on arterial structure and compliance

1. Large artery dilatation may be produced by angiotensin-converting enzyme inhibition in hypertensive subjects independently of blood pressure reduction. The resulting increase in arterial compliance may be due to both blood pressure reduction and to arterial smooth muscle relaxation. 2. In healthy volunteers and in hypertensive subjects, dosages producing large artery dilatation seem to be even higher than those causing arteriole dilatation with the resulting blood pressure reduction. 3. It may be important to consider such findings for the remodelling of the cardiovascular system produced by angiotensin-converting enzyme inhibition.

Upper extremity aneurysm in infants

We report a 2-month-old female infant with a false aneurysm of the brachial artery and an 8-month-old male infant with a true aneurysm of a common digital artery. These traumatic aneurysms in the upper extremity are extremely rare in infants. In the former infant, reanastomosis of the brachial artery was performed. In the latter infant, simple excision was successful.

Fibromuscular dysplasia of the brachial artery: a case report and review of the literature

Fibromuscular dysplasia is a nonatherosclerotic, noninflammatory vascular disease that involves primarily medium-sized and small arteries. Fibromuscular dysplasia is characterized by medical fibrosis with or without smooth muscle cell hyperplasia and may produce luminal impingement with severe turbulence. Secondary aneurysmal deformity with or without thrombosis may also contribute to the obstruction. Fibromuscular dysplasia most commonly involves the renal and carotid arteries, with upper-extremity disease rarely reported. This case report describes a patient with digital embolization from brachial artery fibromuscular dysplasia. Angiography demonstrated significant narrowing and irregularity with a characteristic "string-of-beads" appearance of the right midbrachial artery. The abnormal segment was resected and reconstructed with a reversed saphenous vein graft. Histologic studies revealed disruption of the internal elastic lamina and disorientation of the hyperplastic medial smooth muscle cells characteristic of fibromuscular dysplasia.

Large artery function in patients with chronic heart failure. Studies of brachial artery diameter and hemodynamics

BACKGROUND

Although progressive chronic congestive heart failure (CHF) is associated with elevated systemic vascular resistance and increased impedance to ventricular outflow, the contribution of changes in large artery function has not been well documented in humans.

METHODS AND RESULTS

We studied 45 patients with a broad range of clinical severity of CHF and compared noninvasive measurements of brachial artery diameter, flow, and pulse wave velocity with 22 normal controls of similar age. In CHF, mean arterial pressure was lower than in controls (85 +/- 1 versus 93 +/- 2 mm Hg, p less than 0.001), as were brachial artery diameter (4.07 +/- 0.10 versus 4.53 +/- 0.09 mm, p less than 0.001), flow (40.9 +/- 4.1 versus 70.9 +/- 11.5 ml.min-1, p less than 0.02), compliance (1.29 +/- 0.12 versus 2.00 +/- 0.18 cm4.dyne-1.10(-7), p less than 0.002), and conductance (0.49 +/- 0.05 versus 0.76 +/- 0.13 units, p = 0.06). Limb vascular resistance (40.2 +/- 5.0 versus 20.5 +/- 3.1 units, p less than 0.001) and pulse wave velocity (10.6 +/- 0.5 versus 9.2 +/- 0.4 m.sec-1, p less than 0.03) were higher than in controls. Brachial artery diameter was progressively lower than in controls as severity of CHF increased (New York Heart Association class II, 4.47 +/- 0.23 mm, p = NS; class III, 4.05 +/- 0.10 mm, p less than 0.05; class IV, 3.71 +/- 0.28 mm, p less than 0.05). Similar changes were observed for arterial compliance (class II, 1.76 +/- 0.32 cm4.dyne-1.10(-7), p = NS; class III, 1.21 +/- 0.13 cm4.dyne-1.10(-7), p less than 0.05; class IV, 0.95 +/- 0.10 cm4.dyne-1.10(-7), p less than 0.05). While the lower arterial pressure and flow might be expected to passively reduce arterial diameter, this would be associated with a reduced pulse wave velocity and improved arterial compliance, yet the opposite was observed. Differences in large artery function were not likely caused by underlying atherosclerosis alone, because patients with dilated cardiomyopathy and patients with ischemic heart disease of the same sex, age, left ventricular ejection fraction, and exercise treadmill duration had similar changes in large artery function.

CONCLUSIONS

We conclude that alterations in brachial artery function are present in patients with moderate and severe CHF. The observed reduction in arterial compliance, if present diffusely throughout the arterial tree, could increase left ventricular end-systolic stress directly and through increased velocity of reflected pressure waves from the periphery.

Digital artery embolization as a result of fibromuscular dysplasia of the brachial artery

A 74-year-old woman was admitted to the hospital with sudden onset of a blue, painful right index finger, and the condition progressed to digital ulceration. The ulcer gradually healed over a period of 2 months. Peripheral pulses, Doppler-derived brachial and radial systolic pressures, and results of an echocardiogram were normal. Digital pulse volume recordings showed obstructive waveforms in all digits of the right hand. Arteriography showed a normal arch and normal innominate, subclavian, and axillary arteries. The midbrachial artery was markedly abnormal and had alternating areas of stenosis and aneurysm formation. Multiple occlusions involved the palmar arch and proper digital arteries. The abnormal brachial artery segment was excised and replaced with an autogenous reversed saphenous-vein conduit. Histologic examination confirmed the lesion to be medial fibromuscular dysplasia. Fibromuscular dysplasia that involves upper extremity arteries is extremely uncommon and rarely presents with digital artery embolization. This case emphasizes the importance of exclusion of proximal reconstructible arterial occlusive disease by means of complete arteriographic examination of patients who were admitted with unilateral finger or hand ischemia.

Delayed brachial artery occlusion owing to a dog bite of the upper extremity

We report a case of delayed presentation of vascular injury from a superficial dog bite of the upper extremity in a five-year-old male. This example of a significant arterial injury, in the setting of seemingly minor trauma, is the first known report of blunt arterial trauma owing to a dog bite in any age group. Blunt arterial trauma in children is rare unless associated with fractures, dislocations, or massive crush injuries. Additionally, persistent pulses following arterial occlusion are rare and can potentially lead to misdiagnosis of a serious arterial injury. A brief review of pediatric blunt vascular injuries is presented with implications for diagnosis and management of such cases.

Non-invasive evaluation of segmental pressure drop and resistance in large arteries in humans based on a Poiseuille model of intra-arterial velocity distribution

STUDY OBJECTIVE

The aim of the study was to evaluate in hypertensive subjects the longitudinal pressure drop and segmental resistance in a large artery in relation to shearing forces of the circulating blood column at the arterial wall.

DESIGN

Arterial diameter, blood velocity, and flow were measured in the brachial artery using pulsed Doppler apparatus. Blood viscosity was measured at 96 s-1 with a low shear viscometer. Segmental resistance per unit arterial length was calculated using the basic Poiseuille resistance expression from the ratio between blood viscosity and the fourth power of arterial diameter. Longitudinal pressure drop was deduced as the product between segmental resistance and blood flow. The Poiseuille model of velocity distribution also enabled wall shear rate and stress to be calculated from the ratio between blood velocity and arterial diameter and from the product between shear rate and blood viscosity respectively.

PATIENTS

19 ambulatory male patients with mild to moderate hypertension and 11 normotensive male controls of similar age were studied.

RESULTS

Compared to controls, hypertensive patients had higher arterial diameter (p less than 0.001) lower blood velocity (p less than 0.05), higher blood viscosity (p less than 0.01), lower segmental resistance and pressure drop (p less than 0.001, p less than 0.01) and lower shear rate and stress (p less than 0.01, p less than 0.05). A negative correlation existed in the overall normotensive and hypertensive population between pressure drop and mean blood pressure (r = -0.55, p less than 0.01).

CONCLUSION

The hypertensive state is associated with a clear reduction in large artery segmental resistance and longitudinal pressure drop concomitantly with a decrease in shear conditions at the arterial wall. The mechanisms of reduced resistance and pressure drop are related to decreased wall shear and increased diameter of the artery, both of which reduce the frictional forces at the blood-arterial wall interface.

Non-traumatic cervicomediastinal vascular lesions. A clinicopathological study in the different populations of Natal

Apart from those suffering from vascular trauma, 334 patients with cervicomediastinal lesions have been treated at Durban Metropolitan Hospitals over a period of 8 years. Sixty-seven of these were black (20%), 79 Indian (24%), 10 coloured (3%) and 178 white (53%). Atherosclerotic disease was found in 50% of black, 80% of Indian and 99% of white patients; the remaining patients suffered from miscellaneous conditions, such as arteritis, fibromuscular dysplasia, mucoid degeneration and radiation. Aneurysmal disease was found in 33% of blacks, but only 2% of Indians and 0.6% of whites; the remainder had occlusive lesions. More blacks presented with complete stroke (16%) than in the other population groups, who presented most frequently with episodic neurological dysfunction. It is concluded that atherosclerosis is as common as arteritis in blacks, while it is the most common precipitating factor for cervicomediastinal lesions in the other two groups. Aneurysms and complete stroke are also common in blacks.

Abnormal wall shear conditions in the brachial artery of hypertensive patients

Brachial artery wall shear phenomena were studied in 20 untreated essential hypertensive patients and in 11 normotensive controls of similar age. A pulsed-Doppler velocimeter was used to measure brachial artery internal diameter and mean cross-sectional and systolic centreline blood velocities. A coaxial-cylinder viscometer was used to measure blood viscosity at a shear rate of 96 s-1. A Poiseuille model of velocity distribution across the arterial lumen was used to determine wall shear rate and stress from, respectively, the ratio of blood velocity to arterial diameter and the product of shear rate and blood viscosity. Mean and systolic shear rates and stresses were calculated using, respectively, mean cross-sectional and systolic centreline blood velocities. Hypertensive patients had larger brachial artery diameters (P less than 0.001), lower systolic centreline and mean cross-sectional blood velocities (P less than 0.001, P less than 0.05), higher blood viscosity (P less than 0.001), lower mean and systolic wall shear rates (P less than 0.01, P less than 0.001) and lower systolic wall shear stress (P less than 0.05) than normotensive controls. In all subjects, mean blood pressure was negatively correlated both with mean and systolic shear rates (r = -0.38, P less than 0.05;r = -0.45, P less than 0.01). Thus the hypertensive state was associated with decreases in both mean and systolic wall shear rates, and in systolic wall shear stress. These shear abnormalities merit attention because of the atherogenic effect of low-shear conditions.