Quality of life in vascular anomalies

Hemangiomas and vascular malformations that cause disfigurement or functional limitations may affect the quality life of the affected individual and their families. Negative reaction from strangers, social stigmatization, sadness, stress and low self-esteem are some of the commonly reported effects of having such lesions. Extensive and accurate education about the disease process and advice from support groups may improve quality of life. Psychological intervention may be indicated for some individuals and families.     

Genetics of vascular anomalies: an update

Vascular anomalies arise from genetic, environmental, mechanical, and/or hormonal factors. Some are inherited in a Mendelian fashion whereas others result from abnormal chromosomal segregation during gametogenesis or appear sporadically during various stages of life. Understanding the molecular basis of vascular development and vascular anomalies provides potential tools for diagnosis and treatment of the diseases.     

Circulating endothelial progenitor cells and vascular anomalies

Recent findings regarding pathways of stem/progenitor cell involvement in adult blood vessel growth (postnatal vasculogenesis) suggest new theories for the pathogenesis of vascular anomalies. The somatic growth of vascular malformations and the mysterious pattern of proliferation and involution in infantile hemangioma can no longer be purely understood through the paradigm of angiogenesis. Molecular signals for postnatal vasculogenesis are being discovered in numerous animal models of cancer and ischemia, yet little research has addressed the importance of vasculogenesis in the growth of vascular anomalies. In this review, we discuss early studies that have investigated stem/progenitor cell involvement in the pathophysiology of infantile hemangioma and other congenital vascular anomalies.     

Update on the molecular genetics of vascular anomalies

Genetic factors play a critical role in the pathogenesis of vascular anomalies. Significant advances have been made in recent years in identifying the genetic and molecular determinants of a variety of vascular anomalies using a molecular genetic approach. Several genes for vascular anomalies have been identified. These genes include AGGF1 for Klippel-Trenaunay syndrome, RASA1 for capillary malformations, KRIT1, MGC4607, PDCD10 for cerebral cavernous malformations, glomulin for glomuvenous malformations, TIE2 for multiple cutaneous and mucosal venous malformations, VEGFR-3, FOXC2, NEMO, SOX18 for lymphedema or related syndromes, ENG, ACVRLK1, MADH4 for HHT or related syndromes, NDP for Coats' disease, Notch3 for CADASIL, and PTEN for Proteus Syndrome. These findings have made genetic testing possible in some clinical cases, and may lead to the development of therapeutic strategies for vascular anomalies. Furthermore, these studies have identified critical genes involved in vascular morphogenesis, and provided fundamental understanding of the molecular mechanisms underlying vasculogenesis and angiogenesis.     

Updated classification of hemangiomas and other vascular anomalies

Vascular anomalies comprise a widely heterogenous group of tumors and malformations. Great confusion has arisen because of the term hemangioma has been and is continued to be used to represent a multitude of vascular entities. This review presents the updated classification of vascular anomalies with the goal of clarifying the term hemangioma. In addition, newer clinical concepts in hemangiomas and other vascular tumors is presented. Hemangioma subtypes and hemangioma variants are also discussed, and a brief review of pyogenic granuloma and Kaposiform hemangioendothelioma is provided. Finally, the immunohistochemical marker GLUT1 is reviewed, a marker that heralds a new era in vascular anomalies research.     

Graded cutaneous vascular responses to dynamic leg exercise

The cutaneous vascular conductance-esophageal temperature (CVC-Tes) relationship was examined at five work loads (75-200 W) in each of four men to find whether there is a role for exercise intensity in the control of skin blood flow (SkBF). Several factors contributed to our evaluation of the CVC-Tes relationship during work. Laser-Doppler velocimetry (LDF) provided a continuous measure of SkBF that is not influenced by underlying muscle blood flow. Local warming to 39 degrees C at the site of measurement of SkBF provided a consistent skin temperature and facilitated observation of changes in LDF. Mean arterial pressure was measured noninvasively once per minute to calculate CVC. Supine exercise minimized baroreceptor-induced cutaneous vasoconstriction. Our major finding was that the internal temperature at which CVC began to rise during exercise (CVC threshold) was graded with work load beyond 125 W (P less than 0.05). In that range the CVC threshold increased by 0.16 degrees C for every increment of 25 W. The CVC threshold was never reached at the highest work load in three of the four subjects. There was no consistent effect of work load on the slope of the CVC-Tes relationship or on the internal temperature at which sweating began during exercise (sweat rate threshold). We conclude that the level of work beyond 125 W affects the CVC-Tes relationship in a graded fashion, principally through shifts in threshold.     

Galanin mediated inhibitory nervous modulation of cutaneous vascular reactions

Noxious stimulation induces local inflammatory responses in a variety of mammals but these reactions are only faint in avian species. The possibility that endogenous galanin inhibits neurogenic vascular responses in avians was tested in the wing skin of anaesthetized pigeons. Intraarterial infusion of nanomolar concentrations of the specific galanin antagonist M35 dose dependently enhanced the small mustard oil induced increase of skin blood flow measured by means of a Laser Doppler Imager. Similarly, the small transient vasodilatation following electrical stimulation of a cutaneous nerve was also enhanced by M35. The effect of M35 was not observed after chronic denervation. Coperfusion of M35 dose dependently augmented the histamine and bradykinin induced plasma extravasation revealed by skin microdialyses, but this effect was abolished in the chronically denervated skin. However, chronic denervation per se enhanced the plasma extravasation induced by histamine but not by bradykinin and this effect was diminished by coperfusion of galanin. The results suggest an inhibitory modulation of cutaneous neurogenic inflammatory reactions by endogenous galanin in the pigeon.     

Noninvoluting congenital hemangioma: a rare cutaneous vascular anomaly

The authors studied a rare, congenital, cutaneous vascular anomaly that grows proportionately with the child and does not regress. A total of 53 patients were compiled from three vascular anomaly centers. These patients' lesions were analyzed for presentation, physical findings, radiologic and histopathologic characteristics, natural history, and outcome after resection.The lesions occurred slightly more often in male patients, always appeared alone, and were located (in order of frequency) in the head/neck region, extremities, and trunk. They were round-to-ovoid in shape, were plaque-like or bossed, occurred in variable shades of pink to purple, and had an average diameter of 5 cm. The overlying skin was frequently punctuated by coarse telangiectasia, often with central or peripheral pallor. The lesions were warm on palpation; fast-flow was further documented by Doppler ultrasonography. Magnetic resonance imaging and angiographic findings were similar to those of common hemangioma of infancy. All lesions were easily excised without recurrence.Histologic examination revealed lobular collections of small, thin-walled vessels with a large, often stellate, central vessel. Interlobular areas contained predominantly dilated, often dysplastic veins; arteries were also increased in number. Small arteries were observed "shunting" directly into lobular vessels or into abnormal extralobular veins. "Hobnailed" endothelial cells lined the small intralobular vessels. Mast cells were increased. Tests for glucose transporter-1, a recently reported reliable marker for common hemangioma of infancy, were negative in all 26 specimens examined.In conclusion, the authors think these clinicopathologic and radiologic features define a rare vascular lesion for which the term "noninvoluting congenital hemangioma" is proposed. These lesions of intrauterine onset may be a variant of common hemangioma of infancy or another hemangiomatous entity with persistent fast-flow.     

Prenatal diagnosis of vascular anomalies: update and review of the literature

Optimal care for a subgroup of infants with complicated vascular anomalies requires prenatal diagnosis. Fetal vascular lesions are either vascular tumors or vascular malformations, both of which are often detected on routine ultrasound. Imaging, such as ultrasound and fetal MRI, can be used to examine lesions and provide the data for a differential diagnosis, which may impact the course of care both in utero and postnatally. Prenatal diagnosis provides the opportunity for antenatal intervention, parental counseling, and planning of the mode and location of delivery to optimize postnatal care. Prenatal diagnosis of vascular lesions also serves to alert the physician to the potential for associated syndromes and complications. Any indication of a vascular anomaly should be referred for further examination by an experienced multidisciplinary team of physicians to ensure the window in which evaluation, planning, and treatment can take place is not missed.     

Effect of work load on cutaneous vascular response to exercise.

The purpose of the present study was to examine whether intensity of exercise affects skin blood flow response to exercise. For this purpose, six healthy men cycled, in a random order on different days, for 15 min at 50, 60, 70, 80, and 90% of their maximum oxygen consumption (VO2max) at a room temperature of 25 degrees C. At the end of exercise, esophageal temperature (Tes) averaged 37.4 +/- 0.2, 37.7 +/- 0.2, 37.9 +/- 0.2, 38.6 +/- 0.3, and 38.9 +/- 0.4 degrees C (SE) at the 50, 60, 70, 80, and 90% work loads, respectively. At the two highest work loads, no steady state was observed in Tes. Skin blood flow was estimated by measuring forearm blood flow (FBF) with strain-gauge plethysmography and by laser-Doppler flowmetry on the upper back. Both techniques showed that skin blood flow response to rising Tes was markedly reduced at the 90% work load compared with other work loads. At the end of exercise, FBF averaged 7.5 +/- 1.7, 10.7 +/- 3.1, 9.6 +/- 2.1, 11.3 +/- 2.6, and 5.4 +/- 1.3 (SE) ml.min-1.100 ml-1 (P less than 0.01) at the 50, 60, 70, 80, and 90% VO2max work loads, respectively. The corresponding values for Tes threshold for cutaneous vasodilation (FBF) were 37.42 +/- 0.16, 37.48 +/- 0.13, 37.59 +/- 0.13, 37.79 +/- 0.19, and 38.20 +/- 0.22 degrees C (P less than 0.05) at 50, 60, 70, 80, and 90% VO2max, respectively. In two subjects, no cutaneous vasodilation was observed at the 90% work load.(ABSTRACT TRUNCATED AT 250 WORDS)