Arch Abnormalities Research Articles

Aortic Arch Abnormality in a Patient with Klippel-Feil Syndrome

We present a case of a 43-year-old female with headaches, progressive paresthesias of the upper extremities, and vertigo. Ultrasonography could not visualize the left internal carotid artery (ICA). Magnetic resonance imaging (MRI) showed complete fusion of the C5, C6, and C7 levels, representing Klippel-Feil deformity. Angiography showed a unique abnormality of the aortic arch with complete absence of the left ICA. An embryologic defect associated with this type of abnormality is proposed, with defects of development of the third aortic arch and the aortic sac secondarily.

3-D echocardiographic imaging of double aortic arch

Delineation of arch abnormalities is difficult by conventional 2-D echocardiography and MRI has been the investigation of choice. 3-D echocardiography is increasingly used in congenital heart disease for both functional anatomy and morphology. This case report demonstrates that 3-D echocardiography can be used in delineating arch anomalies, which can avoid further imaging that needs a general anaesthetic.

Images in anesthesia: transesophageal echocardiography during cesarean section in a marfan’s patient with aortic dissection

with Marfan’s syndrome presented to the emergency room with chest, back, and epigastric pain. Echocardiography three months earlier had shown mild aortic dilatation (37 mm) and mitral valve prolapse. Both transesophageal echocardiography (TEE) and computer tomography confirmed aortic dissection from the take-off of the left subclavian artery that extended past the bifurcation and to the iliac arteries. The patient was hospitalized in the intensive care unit (ICU) near the cardiothoracic surgery department for invasive monitoring that confirmed acute (Stanford) type B aortic dissection.1 Antihypertensive, sedative, and steroid therapy were administered immediately. Three days later, because of exacerbation of pain, the patient was scheduled for Cesarean section with preparation for aortic replacement in case of expansion of the dissection into the aortic arch or other unexpected and untoward complications. General anesthesia was induced with fentanyl, propofol, and rocuronium to minimize cardiovascular response to tracheal intubation, and the TEE probe was immediately positioned to monitor the condition of the dissection (video available at www.cja-jca.org). The patient remained hemodynamically stable throughout delivery and was returned to the ICU for continuous conservative treatment. Two weeks later she was discharged in good health. The baby suffered from bilateral hydronephrosis (no genetic information available to date) and mild aortic arch abnormalities compatible with Marfan’s syndrome. In the past, women with Marfan’s syndrome were counseled to avoid the risk of pregnancy and delivery. Today, with improved means of identifying patients that facilitate better care, increased longevity, and improved quality of life, more women with Marfan’s syndrome are attempting to have babies, despite the high risk of aortic dissection even in the absence of aortic root dilatation prior to pregnancy. For this reason, intraoperative TEE observation ensures an extra measure of real-time control during Cesarean section, particularly in case of acute or chronic aortic dissection, and risk factors such as aortic diameter $ 40 OBSTETRICAL AND PEDIATRIC ANESTHESIA 737

Study on the common teratogenic pathway elicited by the fungicides triazole-derivatives

Triazole-derivatives alter the pharyngeal apparatus morphogenesis of rodent embryos cultured in vitro. The hindbrain segmentation and the rhombencephalic neural crest cell (NCCs) migration are altered by Fluconazole exposure in vitro. The aim of the present work is to identify if a common pathogenic pathway is detectable also for other molecules of this class of compounds. 9.5 days post coitum (d. p.c.) old rat embryos were exposed in vitro to the teratogenic concentrations of Flusilazole, Triadimefon and Triadimenol and cultured for 24, 48 or 60 h. The expression and localisation of Hox-b1 and Krox-20 proteins (used as markers for hindbrain segmentation) were evaluated after 24 h of culture. The localisation and distribution of NCC was evaluated after 24, 30 and 48 h of culture. The morphology of the embryos was analysed after 48 h, while the branchial nerve structures were evaluated after 60 h of culture. Hindbrain segmentation and NCC migration alteration as well as pharyngeal arch and cranial nerve abnormalities were detected after exposure of the tested molecules. A common severe teratogenic intrinsic property for the tested molecules of this chemical class has been found, acting through alteration of the normal hindbrain developmental pattern.

Late-onset dysphagia lusoria assessed by 3-dimensional computed tomography of an aortic arch abnormality

Symptomatic vascular rings causing late-onset dysphagia (dysphagia lusoria) are quite unusual in adults. We present a 42-year-old woman with a 1-year history of dysphagia from a right-sided aortic arch with an aberrant left subclavian artery and left-sided ligamentum arteriosum. Using a helical CT scan of the chest and a three-dimensional reconstruction software, her anatomic abnormality was completely delineated. Arch aortogram confirmed the anomaly. The patient underwent a left posteriolateral thoracotomy. Intraoperative findings correlated precisely with the preoperative reconstruction data. Division of the ligamentum resulted in a complete decompression of the esophagus and resolution of the patient's symptoms.

Life-threatening cryoglobulinemia in HCV-negative Southern Chinese and a novel association with structural aortic abnormalities

Cryoglobulinemia is uncommon in Southern Chinese in Hong Kong, with tropical climates and low incidence of hepatitis C virus (HCV) infection. Eight positive cases were detected among 481 patients screened for cryoglobulins over a 10-year period. Three HCV carriers (38%) ran benign courses. The others included two carriers of hepatitis B virus (HBV), two patients with adenocarcinoma, and one with chronic lymphocytic lymphoma. Four of them (except one HBV carrier) ran fulminant courses and died of cryoglobulin-related complications. Interestingly, all four cases also had structural aortic abnormalities, including multiple dissections, aneurysms, and congenital aortic arch abnormalities, which were often life threatening. The association of aortic abnormality and cryoglobulinemia is hitherto unreported and may be peculiar to our ethnic group. Aggressive control of the cryoglobulin may help to reduce aortic intima damage.

OC176: The aberrant right subclavian artery is a common aortic arch abnormality in fetuses with Down's syndrome

Objective: Conversely to the normal right subclavian artery arising from the brachiocephalic artery, an aberrant right subclavian artery (ARSA) arises as a separate vessel from the aortic isthmus and crosses to the right, behind the trachea. This variant is present in less than 1% of the normal population but pediatric cardiology observations report on a frequent occurrence in subjects with Down’s syndrome (DS). The purpose of this study was to assess the possibility of detecting an ARSA in fetuses with DS. Patients and Methods: 14 fetuses with prenatally detected DS were examined between 18 and 33 weeks of gestation. The right subclavian artery was visualized in the transverse three-vesseltrachea view of the upper thorax using color Doppler to detect a normal arising vessel or an ARSA. Results: An ARSA was identified in 35.7% (5/14) of trisomy 21 fetuses. In only one fetus it was associated with a cardiac defect (AVSD) and the four others it was either isolated (n = 1) or associated with an intracardiac echogenic focus. Conclusions: This preliminary study suggests that the in utero identification of an ARSA may be a new ultrasound marker found in fetuses with Down’s syndrome.

Relationship between hindbrain segmentation, neural crest cell migration and branchial arch abnormalities in rat embryos exposed to fluconazole and retinoic acid in vitro

Fluconazole (FLUCO) and retinoic acid (RA) can perturb morphogenesis of the branchial apparatus in rodent embryos exposed in vitro. The aim of the present study was to compare the effects induced by in vitro exposure to FLUCO or to RA on rhombomere organisation, neural crest cell (NCC) migration and cranial nerve differentiation using specific antibodies. For this purpose 9.5 d.p.c. rat embryos were exposed to teratogenic concentrations of FLUCO or RA; another group was exposed to no-effect concentrations of both agents. Expression of Hox-b1 and Krox20 (markers of specific rhombomeres) was altered after FLUCO and RA exposure. Furthermore, FLUCO and RA showed a synergistic effect. These results suggest that the observed branchial abnormalities are due to anomalous NCC migration related to incorrect organisation of specific rhombomeres.

Left-sided cervical aortic arch aneurysm: case report

Cervical aortic arch is a rare type of vascular congenital anomaly. Aneurysmal formation has been reported in only 10 cases but is seen occasionally by experienced thoracic aortic surgeons.1Farsak B Yilmaz M Kaplan S Böke E Cervical aortic arch with aneurysm formation.Eur J Cardiothorac Surg. 1998; 14: 437-439Crossref PubMed Scopus (18) Google Scholar Although most of the patients with this anomaly are asymptomatic, newer imaging techniques demonstrate aneurysmal change in the cervical arch, and pathologic findings in surgical series support the indication for surgical intervention.2Cooly D.A Mullins C.E Gooch J.B Aneurysm of right-sided cervical arch; surgical removal and graft replacement.J Thorac Cardiovasc Surg. 1976; 72: 106-108PubMed Google Scholar A 16-year-old woman was admitted to Asahi General Hospital with a pulsatile mass in the left neck. Blood pressure was 110/60 mm Hg in the right arm and 90/60 mm Hg in the left arm. Examination of the neck revealed a visible 4-cm pulsatile mass in the left supraclavicular region. A thrill with a grade II/VI bruit was noted over the left carotid artery. Chest radiography revealed a smooth left-sided mediastinal mass. Three-dimensional computed tomography (3D-CT), magnetic resonance angiography (MRA), and aortography revealed a saccular aneurysm of the cervical aortic arch just distal to the origin of the left carotid artery, with normal branching. An aberrant and torturous left subclavian artery originated from the distal end of the aneurysm (Figure 1). The aortic arch, the descending aorta, and the left subclavian artery were accessed via a left thoracotomy in the fourth intercostal space. The left superior vena cava was dissected from the aneurysm. After systemic heparinization (200 IU/kg body weight), the descending aorta and inferior vena cava were cannulated, and partial cardiopulmonary bypass was established. After core cooling to a rectal temperature of 34°C, the aorta was then clamped just distal to the left carotid artery and the descending aorta, after which the subclavian artery was clamped and divided. The aneurysm was excised, and a 22-mm Hemashield graft (woven double velour graft; Boston Scientific, Natick, Mass) was anastomosed in an end-to-end fashion. The aberrant subclavian artery was reconstructed to the side of the graft by using an interposed 8-mm Hemashield graft. Pathologic examination revealed cystic medial degeneration of the aortic arch. Deletion of chromosome 22q11 was not detected in genetic analysis. The postoperative course and 4-year follow-up were uneventful (Figure 2). Cervical arch abnormalities are not that rare to experienced, high-volume thoracic aortic surgeons and are common in patients with a bicuspid aortic valve. However, this condition is rarely reported or discussed in the literature. Cervical aortic arch was first described in 1914, and it was postulated that the anomaly arises from an abnormal persistence of the third aortic arch and the regression of the fourth arch, which normally forms the aortic arch.3Reid D.G Three examples of a right aortic arch.J Anat Physiol. 1914; 48: 174-181PubMed Google Scholar The pathophysiology of aneurysmal dilatation is unknown. Most patients with this malformation are asymptomatic but patients may have symptoms of vascular compression of the esophagus and trachea, which manifest as dysphagia, dyspnea, or frequent pulmonary infections. Dysphagia and respiratory distress are associated with a right-sided cervical arch, whereas aneurysmal formations are more often associated with a left-sided cervical arch. Physical examination reveals a large pulsatile mass in the supraclavicular region.4Morris R Ruttley M Left cervical aortic arch associated with aortic aneurysm.Br Heart J. 1978; 40: 87-90Crossref PubMed Scopus (17) Google Scholar 3D-CT, angiography and MRA are useful for definite diagnosis and surgical treatment. Deletion of chromosome 22q11 was recently reported in some cases of cervical aortic arch5Kumar A McCombs J.L Sapire D.W Deletions in chromosome 22q11 region in cervical aortic arch.Am J Cardiol. 1997; 79: 388-390Abstract Full Text Full Text PDF PubMed Scopus (28) Google Scholar but was not evident in this case. The female predilection for aneurysm formation is consistent with a genetic factor.1Farsak B Yilmaz M Kaplan S Böke E Cervical aortic arch with aneurysm formation.Eur J Cardiothorac Surg. 1998; 14: 437-439Crossref PubMed Scopus (18) Google Scholar The pathologic finding of cystic medial degeneration in the aneurysm has been reported in a large surgical series and supports the importance of recognition and surgical intervention in this condition, whether patients are symptomatic or not.2Cooly D.A Mullins C.E Gooch J.B Aneurysm of right-sided cervical arch; surgical removal and graft replacement.J Thorac Cardiovasc Surg. 1976; 72: 106-108PubMed Google Scholar

High incidence of cardiac malformations in connexin40-deficient mice.

Gap junctions are intercellular channels formed by oligomerization of a protein called connexin (Cx). The heart expresses at least three connexin isotypes: Cx40, Cx43, and Cx45. A possible role for Cx40 in cardiac morphogenesis remains to be determined. We have characterized the anatomy and histology of fetal and newborn hearts obtained from crossing Cx40-deficient mice of mixed genetic background (C57BL/6x129Sv). Hearts were serial-sectioned (5 microm) along the coronal plane, stained with hematoxylin-eosin, and visualized by conventional light microscopy. Cardiac malformations in mice lacking Cx40 in one allele (Cx40+/-) included bifid atrial appendage, ventricular septal defect, tetralogy of Fallot (TOF), and an aortic arch abnormality. In Cx40-/- mice resulting from crossing of Cx40+/- mice, the most common cardiac malformations were double-outlet right ventricle (DORV), TOF, and endocardial cushion defects. Overall incidence of cardiac malformations was 6/33 (18%) in Cx40+/- mice and 4/12 (33%) in Cx40-/- mice. No cardiac malformations were observed in 15 wild-type mice studied. In addition, we examined 39 hearts from offspring of Cx40-/- matings. Frequency of cardiac malformations was even higher in this group (44%). Over one third of the hearts (14 of 39) showed conotruncal malformations corresponding to either DORV or TOF. Endocardial cushion defects were found in 3 out of 39 hearts. Our results suggest that Cx40 participates in cardiac morphogenesis, likely in association with other (unknown) products whose expression may vary with the genetic background of the mice.

Split spinal cord malformations: report of 22 cases and review of the literature.

The aims of this study were to describe the embryological changes that drive the formation of a split spinal cord malformation, analyse the forms of presentation, evaluate the diagnostic procedures and discuss the indications for the different forms of therapy for each case. Clinical and radiological features of 22 cases of split spinal cord malformations (SSCM) are reported. Three groups of patients are considered: group a, patients with signs of tethered cord or scoliosis; group b, patients with midline cutaneous stigmata and group c, patients with a meningocele or meningomyelocele. While CT scan is particularly useful for the evaluation of vertebral bodies and posterior arch abnormalities and spur characteristics in SSCM, MRI gives complementary information on the anatomy of spinal cord, dural sac, conus and filum terminale and permits the exclusion of associated lesions such as hydro-syringomyelia, dermal sinus or dermoid and epidermoid cysts. Surgery should be considered indicated in all cases of SSCM, even the asymptomatic ones, except in very badly handicapped meningomyelocele patients with nonprogressive disability and type II SSCM.

Pathogenic pathways in fluconazole-induced branchial arch malformations.

A widely-used antimycotic agent, bis-triazole fluconazole (FLUCO), is able to produce abnormalities to the branchial apparatus (hypoplasia, agenesis, and fusion) in postimplantation rodent embryos cultured in vitro. The branchial apparatus is a complex and transient structure in vertebrate embryos and is essential for the development of the face skeleton. Branchial arch mesenchyme is formed by two different cellular populations: paraxial mesenchyme and ectomesenchyme, which originate from rhombencephalic neural crest cell (NCC) migration. We investigated the possible pathogenic pathways involved in FLUCO-related branchial arch abnormalities. Perturbations in physiological apoptosis, cell proliferation, NCC migration and branchial mesenchyme induction have been considered. Rat embryos (9.5-day postcoitum; 1-3 somites) were exposed in vitro to 0 or 500 microM FLUCO. After 24, 36, or 48 hr of culture, embryos were examined for apoptosis (acridine orange method) and cell proliferation (BrdU incorporation and detection method). Rhombencephalic NCC migration was analyzed using immunostaining of NCC (using anti-CRABP antibodies) and the extracellular matrix (using anti-fibronectin antibodies). The differentiative capability of the branchial mesenchymes was investigated using anti-endothelin and anti-endothelin-receptor antibodies. During the whole culture period, no alterations in physiological apoptosis, cell proliferation, and mesenchymal cell induction were observed in FLUCO-exposed embryos in comparison to controls. On the contrary, severe alterations in NCC migration pathways were observed in FLUCO-exposed embryos. The findings suggest that FLUCO produces teratogenic effects by interfering with the cellular and molecular mechanisms that control NCC migration.

Altered apoptosis pattern during pharyngeal arch artery remodelling is associated with aortic arch malformations in Tgfβ2 knock-out mice

The morphogenetic process underlying the remodelling of the embryonic mammalian pharyngeal arch artery system is unknown. Within this process, the right sixth, carotid ducts and the distal part of the dorsal aorta (right alpha-segment) regress. In order to unravel the underlying mechanism we studied the role of apoptosis in the normal regression of pharyngeal arch artery segments and in a mouse model that develops aortic arch malformations. Normal remodelling was studied in wild-type Swiss (CPBS) and altered remodelling in the Tgfbeta2-/- compared to the Tgfbeta2+/+ (Swiss/Bl6) strain using immunohistochemistry and morphometric analysis. During normal remodelling, apoptosis occurs in the mesenchyme surrounding pharyngeal arch arteries before regression starts. With the onset of regression, apoptosis spreads from the mesenchyme to the media. Morphometric evaluation confirms the increase in apoptosis in the actin-positive media of the disappearing segments. In Tgfbeta2-/-, aberrant apoptosis was found in both fourth arch arteries, whereas the right dorsal aorta lacks apoptosis associated with normal regression. Fourth arch hypoplasia is the main arch abnormality. In the most severe case, the fourth arch is interrupted and the right dorsal aorta alpha-segment persists, giving rise to aortic arch interruption type-B and an aberrant right subclavian artery. We have shown for the first time that specific vascular apoptosis patterns accompany normal regression and that the incidence of apoptosis is selectively altered in the case of arch artery abnormalities in Tgfbeta2 knock-out mice.

Aortoesophageal fistula in a 13-yr-old girl: complication after nasogastric tube placement in the setting of right-sided aortic arch.

To report a case of aortoesophageal fistula in a 13-yr-old girl with a right aortic arch that occurred after nasogastric intubation after surgery for lumbar kyphosis. Case report. Tertiary care pediatric intensive care unit. One 13-yr-old girl who underwent operative repair of a 45-degree kyphosis at the level of the second to fourth lumbar vertebrae. On the eighth postoperative day after operative kyphosis repair and intraoperative placement of a nasogastric tube, sudden massive hematemesis developed and the patient died. Autopsy revealed esophageal ulceration with erosions. One of these had a fistulous tract connecting to the descending aorta. The aortoesophageal fistula was observed where the descending aorta indented the posterior wall of the esophagus, as the aorta crossed the midline from the right side to the left side of the body. In the setting of right-sided aortic arch and other abnormalities of the aortic arch, nasogastric intubation may result in aortoesophageal fistula, massive hemorrhage, and death. Right-sided aortic arch should be added to the list of conditions for which utmost caution during nasogastric intubation is warranted.

A genetic link between Tbx1 and fibroblast growth factor signaling.

Tbx1 haploinsufficiency causes aortic arch abnormalities in mice because of early growth and remodeling defects of the fourth pharyngeal arch arteries. The function of Tbx1 in the development of these arteries is probably cell non-autonomous, as the gene is not expressed in structural components of the artery but in the surrounding pharyngeal endoderm. We hypothesized that Tbx1 may trigger signals from the pharyngeal endoderm directed to the underlying mesenchyme. We show that the expression patterns of Fgf8 and Fgf10, which partially overlap with Tbx1 expression pattern, are altered in Tbx1(-/-) mutants. In particular, Fgf8 expression is abolished in the pharyngeal endoderm. To understand the significance of this finding for the pathogenesis of the mutant Tbx1 phenotype, we crossed Tbx1 and Fgf8 mutants. Double heterozygous Tbx1(+/-);Fgf8(+/-) mutants present with a significantly higher penetrance of aortic arch artery defects than do Tbx1(+/-);Fgf8(+/+) mutants, while Tbx1(+/+);Fgf8(+/-) animals are normal. We found that Fgf8 mutation increases the severity of the primary defect caused by Tbx1 haploinsufficiency, i.e. early hypoplasia of the fourth pharyngeal arch arteries, consistent with the time and location of the shared expression domain of the two genes. Hence, Tbx1 and Fgf8 interact genetically in the development of the aortic arch. Our data provide the first evidence of a genetic link between Tbx1 and FGF signaling, and the first example of a modifier of the Tbx1 haploinsufficiency phenotype. We speculate that the FGF8 locus might affect the penetrance of cardiovascular defects in individuals with chromosome 22q11 deletions involving TBX1.

Anéis vasculares na infância: diagnóstico e tratamento

To present the study carried out by the Pediatric Surgery Department of Instituto da Criança at the Medical School of Universidade de São Paulo regarding the diagnosis and treatment of children with aortic arch abnormalities and to define the role of complementary exams for diagnosis. Retrospective study of 22 patients with diagnosis of tracheoesophageal compression treated at Instituto da Criança from 1985 to 2000, analyzing pre- and postoperative clinical data, diagnostic exams and outcome. The most frequent diagnosis was right aberrant innominate artery (10 cases), followed by double aortic arch (7 cases) and right aortic arch (5 cases). Respiratory symptoms (86%) and early manifestation (76% since the neonatal period) were predominant. Nevertheless, most cases (60%) had the definitive diagnosis established only after 1 year of life. The most relevant examination for the diagnosis was the esophagogram. The correction of all the anomalies was carried out through left postero-lateral thoracotomy. There were no surgical complications. The outcome was worse in patients with delayed treatment. All children remained symptomatic for up to 6 months, although they had significant improvement in the postoperative period. The diagnosis of vascular rings should be considered in children with early respiratory symptoms and in the wheezing baby with difficult control. The diagnosis may be established just through the esophagogram. Other image studies add few information and they are unnecessary in most cases. Less severe symptoms may persist for variable periods.

Comparative study of mouse trisomy 16 and bis‐diamine treated fetuses: Discrimination of possible contribution of neural crest cells to malformations

ABSTRACT In order to directly compare the malformation complex induced by genetic and environmental factors, mouse trisomy 16 (Ts 16) fetuses and bis‐diamine treated (BDT) mouse fetuses in which pregnant females were orally dosed with 3.0 mg and 1.0 mg/B.W. (g) bisdiamine eight hours apart on 9 days of pregnancy, were examined. Cystic hygroma with generalized edema appeared in most Ts 16 and in less than 50% of BDT fetuses. Blunt snout or facial cleft with aplasia or hypoplasia of the olfactory bulb was observed in BDT fetuses. The thymus was markedly to moderately hypoplastic in Ts 16, and absent or markedly hypoplastic in BDT fetuses. Parathyroid glands were inclined to be unsettled in relative location to the thyroid in Ts 16 and absent in BDT fetuses. Aortic arch abnormalities were present in approximately half of the cases of Ts 16 and in the majority of cases of BDT fetuses. In the conotruncal region, double outlet right ventricle and persistent truncus arteriosus were dominantly observed in Ts 16 and BDT fetuses, respectively. Atrioventricular septal defect was observed in every Ts 16 and in about 30% of BDT fetuses. These results indicate that not only environmental factors but also genetic factors can experimentally induce DiGeorge‐Iike anomaly in mice. Abnormal development relevant to neural crest cells seems to occur typically in BDT fetuses, and incompletely in Ts 16 fetuses.

Trauma Centers Bleeding Dollars With Balance Sheets in the Red

In Texas, trauma centers lose, on average, $20 million each year. In California, losses total at least $400 million for the state’s major trauma centers, and the California Medical Association is calling for a $300 million infusion of cash into the state’s trauma system just to maintain the services. “Trauma care in Texas is imperiled,” claims Amir Rubin, chief operations officer at Hermann Hospital in Houston. “Texas’ trauma centers are currently delivering the highest levels of critical services to all Texans around the clock, regardless of HMO plan restrictions, regardless of insurance status. These trauma centers however, cannot sustain losses year after year and remain viable.” In Texas, where motorists rack up the highest number of annual motor vehicle accidents (3901 in 1999), trauma centers often mean the difference between life and death for accident victims, who make up the majority of their patients. However, according to a survey of the state’s Level I and II trauma centers by Mr Rubin, most centers are losing large amounts of money. Trauma in the uninsured population accounts for much of the increase during the past decade, according to Mr Rubin’s study. Twenty-one percent of Texans are without health insurance, he reported, with 31% of the population of Harris County (which includes Houston) and 25% of Dallas County uninsured. During the past year, the volume of trauma increased 5.4%, with concurrent increases in operating losses. At the same time, the federal government cut the funding that goes into state Disproportionate Share Payments. These payments were designed to help defray deficiencies between Medicaid payments and the cost of delivering Medicaid and indigent care (for which there is no reimbursement). Payments to private, nonprofit trauma centers declined 23% and those to public, district facilities dropped 11%. “The survey results reveal not only a bleak financial …

Robert James Graves and the cardiovascular responses to postural changes in heart failure

Circulation 1963;28:1149–1152. 2. Bradley WG. Congenital aortic arch abnormalities with the “subclavian steal” pattern of blood flow. Br Heart J 1966;28:718–720. 3. Pieroni DR, Brodsky ST, Rowe RD. Congenital subclavian steal: report of a case occurring in a neonate and review of the literature. Am Heart J 1972;84: 801–807. 4. Midgley FM, McClenathan JE. Subclavian steal syndrome in the pediatric age group. Ann Thorac Surg 1977;24:252–257. 5. Kajinami K, Mori K, Masuda S, Itoh Y, Morishita E, Imahori E. Asymptomatic congenital subclavian steal in a young male patient with right aortic arch. Chest 1990;97:481–482. 6. Yamakawa H, Nishikawa M, Nakahara I, Inagawa S, Koide T, Handa H. Congenital subclavian steal syndrome with anomaly of the aortic arch. Surg Neurol 1993;39:133–137. 7. Perryman RA, Bayne E, Miller RH. Bull-worker syncope: congenital subclavian steal syndrome following isometric exercise. Pediatr Cardiol 1991;12:105– 106. 8. Naito H, Kurokawa K, Kanno T, Toya S, Osano M. Status epilepticus and cortical blindness due to subclavian steal syndrome in a girl with Blalock’s operation. Surg Neurol 1973;1:46–49. 9. Kurlan R, Krall RL, Deweese JA. Vertebrobasilar ischemia after repair of tetralogy of Fallot: significance of subclavian steal created by Blalock-Taussig anastomosis. Stroke 1984;15:359–362. 10. Deeg KH, Singer H. Doppler sonographic diagnosis of subclavian steal in infants with coarctation of the aorta and interrupted aortic arch. Pediatr Radiol 1989;19:163–166. 11. Deeg KH, Hofbeck M, Singer H. Diagnosis of subclavian steal in infants with coarctation of the aorta and interruption of the aortic arch by color-coded Doppler sonography. J Ultrasound Med 1993;12:713–718. 12. Reivich M, Holling HE, Roberts B, Toole JF. Reversal of blood flow through the vertebral artery and its effect on cerebral circulation. N Engl J Med 1961; 265:878–885.

Symptomatic Vascular Rings in Adulthood: An Uncommon Mimic of Asthma

Symptomatic thoracic vascular rings presenting in adulthood are thought to be rare. During a 3-year time period, we diagnosed four cases of symptomatic vascular rings, which had been treated unsuccessfully for suspected asthma. Spirometry was characterized by normal forced vital capacity (FVC), forced expiratory volume in 1 sec (FEV1), and FEV1/FVC, decreased peak expiratory flow (PEF), and truncation of the expiratory flow volume loop. Chest radiographs revealed a right aortic arch in each case with computed tomography (CT) or magnetic resonance imaging (MRI) confirming the diagnosis of a vascular ring. The specific abnormalities consisted of right aortic arch with mirror branching of the main arteries and persistent ligamentum arteriosum; right aortic arch with diverticulum and a fibrous embryonic left arch; right aortic arch with aberrant left subclavian artery arising from a diverticulum of Kommerell; and a right aortic arch with persistent ligamentum arteriosum. Although they are uncommon, vascular rings first presenting in adulthood as a mimic of asthma are not rare. This diagnosis should be considered in adults when abnormal truncation of the flow-volume loop occurs or when radiographic aortic arch abnormalities are found.