Long-Term Outcomes of Patients With Carotid and Aortic Body Tumors.

Chemodectomas are tumors derived from parasympathetic nonchromaffin cells and are often found in the aortic and carotid bodies. They are generally benign but can cause mass-effect symptoms and have local or distant spread. Surgical excision has been the main curative treatment strategy. The National Cancer Database was reviewed to study all patients with carotid or aortic body tumors from 2004 to 2015. Demographic data, tumor characteristics, treatment strategies, and patient outcomes were examined, split by tumor location. Kaplan-Meier survival estimates were generated for both locations. In total, 248 patients were examined, with 151 having a tumor in the carotid body and 97 having a tumor in the aortic body. Many variables were similar between both tumor locations. However, aortic body tumors were larger than those in the carotid body (477.80 ± 477.58 mm vs 320.64 ± 436.53 mm, p = 0.008). More regional lymph nodes were positive in aortic body tumors (65.52 ± 45.73 vs 35.46 ± 46.44, p <0.001). There were more distant metastases at the time of diagnosis in carotid body tumors (p = 0.003). Chemotherapy was used more for aortic body tumors (p = 0.001); surgery was used more for carotid body tumors (p <0.001). There are slight differences in tumor characteristics and response to treatment. Surgical resection is the cornerstone of management, and radiation can often be considered. In conclusion, chemodectomas are generally benign but can present with metastasis and compressive symptoms that make understanding their physiology and treatment important.

Aortic Body Chemoreceptors Regulate Coronary Blood Flow in Conscious Control and Hypertensive Sheep.

BACKGROUND: Peripheral arterial chemoreceptors monitor the chemical composition of arterial blood and include both the carotid and aortic bodies (ABs). While the role of the carotid bodies has been extensively studied, the physiological role of the ABs remains relatively under-studied, and its role in hypertension is unexplored. We hypothesized that activation of the ABs would increase coronary blood flow in the normotensive state and that this would be mediated by the parasympathetic nerves to the heart. In addition, we determined whether the coronary blood flow response to stimulation of the ABs was altered in an ovine model of renovascular hypertension. METHODS: Experiments were conducted in conscious and anesthetized ewes instrumented to record arterial pressure, coronary blood flow, and cardiac output. Two groups of animals were studied, one made hypertensive using a 2 kidney one clip model (n=6) and a sham-clipped normotensive group (n=6). RESULTS: Activation of the ABs in the normotensive animals resulted in a significant increase in coronary blood flow, mediated, in part by a cholinergic mechanism since it was attenuated by atropine infusion. Activation of the ABs in the hypertensive animals also increased coronary blood flow (P<0.05), which was not different from the normotensive group. Interestingly, the coronary vasodilation in the hypertensive animals was not altered by blockade of muscarinic receptors but was attenuated after propranolol infusion. CONCLUSIONS: Taken together, these data suggest that the ABs play an important role in modulating coronary blood flow and that their effector mechanism is altered in hypertension.

Gastric glomus tumor: A rare etiology of upper gastrointestinal bleed.

The glomus tumor of stomach is an unusual submucosal mesenchymal tumor of the gastrointestinal tract. We describe a 42-year-old female who presented with chronic anemia and an episode of painless hematemesis. A preoperative diagnosis of the probable gastric gastrointestinal stromal tumor was made. Post-surgical histopathological examination of the specimen demonstrated a glomus tumor of the stomach confirmed on immunohistochemistry. The present case highlights the importance of morphology and immunohistochemistry in differentiating the subepithelial tumors of the stomach and one must consider glomus tumor in differential diagnosis of these gastric lesions.

Three-dimensional conformal radiation therapy for canine aortic body tumour: 6 cases (2014-2019).

OBJECTIVE: To determine the feasibility of three-dimensional conformal radiation therapy for canine aortic body tumours. MATERIALS AND METHODS: Medical records of dogs that had undergone three-dimensional conformal radiation therapy with presumptive diagnosis of aortic body tumour were reviewed for clinical characteristics, treatment modality and outcomes. RESULTS: Eight dogs were diagnosed with aortic body tumour and were treated with three-dimensional conformal radiation therapy. One dog had proliferation of a mass in the right atrium during treatment and died of respiratory distress. Another dog did not undergo follow-up CT to evaluate the treatment response due to the increased blood urea nitrogen values. The remaining 6 dogs were included in the case series. Radiotherapy was performed using a median dose per fraction of 7 Gy (3.3-7.14 Gy), a median of seven divided doses (7-15) and a total median dose of 49 Gy (45-50 Gy). The median number of CT scans during the follow-up period was 5 (range: 3-8 times). CT revealed acute side effects in four dogs-grade 1 effects related to the lung (n = 4) and skin (n = 2). Self-limiting or asymptomatic late side effects (grade 1 lung-related effect) were observed in three dogs. After therapy, one dog demonstrated a complete response, another demonstrated a partial response and the disease remained stable in four animals. The median follow-up period was 514.5 (235-1219) days. After three-dimensional conformal radiation therapy, the aortic body tumour reduced gradually over time without regrowth in all these 6 dogs. CLINICAL SIGNIFICANCE: In this small case series, aortic body tumours responded to three-dimensional conformal radiation therapy. Transient and self-limiting side effects of the treatments were common. Further controlled studies are required to prove the effectiveness and the safety of this intervention.

Glomus Vagale Tumor Resection: 2-Dimensional Operative Video.

A 37-yr-old female with prior transient left facial paralysis presented with hearing loss, headaches, and resolved transient right facial paralysis. The neurological examination demonstrated normal facial movement, left hearing loss, and left vocal cord weakness. Magnetic resonance imaging demonstrated a >3 cm left paraganglioma traversing the jugular foramen. After obtaining informed consent from the patient, the tumor was embolized and then resected via a combined left postauricular infratemporal fossa and transcervical approach with cranial nerve monitoring. The ossicles were removed and the vertical segment of the facial nerve was skeletonized. The jugular bulb was identified in the hypotympanum and the petrous carotid artery was exposed. The digastric muscle was reflected inferiorly and the extratemporal facial nerve was identified. The stylomandibular ligament was transected to unlock the exposure to the infratemporal fossa. The external carotid branches were ligated. The vagus nerve and cervical sympathetic chain were infiltrated with tumor, requiring resection. The presigmoid dura and occluded jugular bulb were opened to complete the tumor resection, while preserving the medial wall. Despite anatomic preservation, the glossopharyngeal, accessory, and hypoglossal nerves were postoperatively weak and a facial paralysis recovered after 1 wk. Magnetic resonance imaging at 1 yr demonstrated a clean jugular foramen, although a thin rim of tumor remained around the petrous carotid.

An aortic body carcinoma with sarcomatoid morphology and chondroid metaplasia in a French Bulldog.

An 11-year-old female French Bulldog was presented with a mass at the base of the heart, detected by X-ray and echocardiography. Clinical abnormality included abdominal retention by ascites. Radiation therapy was performed for 5 weeks. The mass volume didn't change during the radiotherapy. The condition became worse and the dog died 6 months after the initial presentation and necropsy was performed. Grossly, the mass, 12.5 × 6.5 × 6.0 cm in size, was found at the base of the heart. Histopathological examination revealed that cardiac mass was composed of alveolar, bundle and diffuse proliferation of neoplastic cells. Most of the neoplastic cells showed a spindle morphology; in some areas small round or polyhedral neoplastic cells were observed. Occasional cartilage metaplasia was seen multifocal in the mass, and it was surrounded by the sarcomatoid proliferation. Electron microscopy revealed a few neuroendocrine granules in the cytoplasm of spindle and polyhedral neoplastic cells. Metastatic cells in the lungs which had not irradiated demonstrated typical morphology of aortic body tumors. Based on these findings, the case was diagnosed as an aortic body carcinoma with sarcomatoid morphology and chondroid metaplasia.

Cross-Sectional Imaging and Thoracoscopic Resection of Functional Intrathoracic Paraganglioma of the Aortic Body.

Paragangliomas are extra-adrenal tumors that are derived from neuroendocrine chromaffin cells. The rare disease has a variable presentation depending upon its anatomic location and functionality. We describe the case of a 56-year-old female patient who had an incidental mass found on imaging. The patient underwent biochemical testing and a mediastinal biopsy due to the nonspecific imaging findings. The mediastinal mass was resected through hemisternotomy and found to be a functional paraganglioma. This case highlights the importance of radiologists to consider the prospect of paragangliomas in the differential diagnosis of an intra-thoracic mass.

[Tumors of glomus vagale: diagnostics and therapy]. / A glomus vagale tumorok kivizsgálása és ellátása.

Introducing the diagnostic protocol and therapy of a rare disease reviewing the worldwide literature named as vagal paraganglioma is our main target. This type is specific for women of middle age, and it is appearing as a unilateral neck mass, with or without Fontaine's sign. Giving a heavy aspect on the ear, nose and throat examination, the most important diagnostic tool is CT-angiography. Carefully looking at the size and relationship with the narrowing arteries, veins, nerves, muscles and bony structures (skull base, cervical spine), in most of the cases we choose the surgical procedure. Orv Hetil. 2019; 160(34): 1358-1362.

Early Peritoneal Dialysis and Major Adverse Events After Pediatric Cardiac Surgery: A Propensity Score Analysis.

OBJECTIVES: Early peritoneal dialysis may have a role in modulating the inflammatory response after cardiopulmonary bypass. This study sought to test the effect of early peritoneal dialysis on major adverse events after pediatric cardiac surgery involving cardiopulmonary bypass. DESIGN: In this observational study, the outcomes in infants post cardiac surgery who received early peritoneal dialysis (within 6 hr of completing cardiopulmonary bypass) were compared with those who received late peritoneal dialysis. The primary outcome was a composite of one or more of cardiac arrest, emergency chest reopening, requirement for extracorporeal membrane oxygenation, or death. Secondary outcomes included duration of mechanical ventilation, length of intensive care, and hospital stay. A propensity score methodology utilizing inverse probability of treatment weighting was used to minimize selection bias due to timing of peritoneal dialysis. SETTING: Cardiac ICU, The Royal Children's Hospital, Melbourne, VIC, Australia. PATIENTS: From 2012 to 2015, infants who were commenced on peritoneal dialysis after cardiac surgery were included. MEASUREMENTS AND MAIN RESULTS: Among 239 eligible infants, 56 (23%) were commenced on early peritoneal dialysis and 183 (77%) on late peritoneal dialysis. At 90 days, early peritoneal dialysis as compared with late peritoneal dialysis was associated with a decreased risk of primary outcome (relative risk, 0.16; 95% CI, 0.05-0.47; p < 0.001 and absolute risk difference, -18.1%; 95% CI, -25.1 to -11.1; p < 0.001). Early peritoneal dialysis was also associated with a decrease in duration of mechanical ventilation and intensive care stay. Among infants with a cardiopulmonary bypass greater than 150 minutes, early peritoneal dialysis was also associated with a survival advantage (relative risk, 0.14; 95% CI, 0.03-0.84; p = 0.03 and absolute risk difference, -7.8; 95% CI, -13.6 to -2; p = 0.008). CONCLUSIONS: Early peritoneal dialysis in infants post cardiac surgery is associated with a decrease in the rate of major adverse events. The role of early peritoneal dialysis warrants the conduct of randomized trials both in high and low-to-middle income countries; any beneficial effects if confirmed have the potential to strongly influence outcomes for children born with congenital heart disease.

Emergency medicine myths and misconceptions: evaluating the evidence.

Medical reversal is common, with rates of reversal of practices that were considered standard of care as high as 40%. Unfortunately, many standards of care are never tested, but instead are often promoted based on pathophysiological explanations or simply being long-established practices. Much of medical practice is based on dogma: a set of principles laid down by authority as incontrovertibly true. This article evaluates four commonly taught dogmatic practices in emergency medicine to determine if they are supported by the medical literature or are instead myths and misconceptions: (1) topical anaesthetics inhibit corneal healing, (2) treatment of myocardial infarction is MONA (morphine, oxygen, nitrates, aspirin), (3) children do not get sprains because their ligaments are stronger than bone, and (4) vagal manoeuvres for supraventricular tachycardia never work in adults. Medicine is changing all the time, and the best way to ensure that one is practicing medicine that is accurate, up to date and not prone to being reversed is to always be sceptical and to learn how to read and interpret the medical literature.

Vasopressin V1a receptors are present in the carotid body and contribute to the control of breathing in male Sprague-Dawley rats.

Vasopressin (AVP) maintains body homeostasis by regulating water balance, cardiovascular system and stress response. AVP inhibits breathing through central vasopressin 1a receptors (V1aRs). Chemoreceptors within carotid bodies (CBs) detect chemical and hormonal signals in the bloodstream and provide sensory input to respiratory and cardiovascular centers of the brainstem. In the study we investigated if CBs contain V1aRs and how the receptors are involved in the regulation of ventilation by AVP. We first immunostained CBs for V1aRs and tyrosine hydroxylase, a marker of chemoreceptor type I (glomus) cells. In urethane-anesthetized adult Sprague-Dawley male rats, we then measured hemodynamic and respiratory responses to systemic (intravenous) or local (carotid artery) administration of AVP prior and after systemic blockade of V1aRs. Immunostaining of CBs showed colocalization of V1aRs and tyrosine hydroxylase within glomus cells. Systemic administration of AVP increased mean arterial blood pressure (MABP) and decreased respiratory rate (RR) and minute ventilation (MV). Local administration of AVP increased MV and RR without significant changes in MABP or heart rate. Pretreatment with V1aR antagonist abolished responses to local and intravenous AVP administration. Our findings show that chemosensory cells within CBs express V1aRs and that local stimulation of the CB with AVP increases ventilation, which is contrary to systemic effects of AVP manifested by decreased ventilation. The responses are mediated by V1aRs, as blockade of the receptors prevents changes in ventilation. We hypothesize that excitatory effects of AVP within the CB provide a counterbalancing mechanism for the inhibitory effects of systemically acting AVP on the respiration.

Chemoreflex mediated arrhythmia during apnea at 5,050 m in low- but not high-altitude natives.

Peripheral chemoreflex mediated increases in both parasympathetic and sympathetic drive under chronic hypoxia may evoke bradyarrhythmias during apneic periods. We determined whether 1) voluntary apnea unmasks arrhythmia at low (344 m) and high (5,050 m) altitude, 2) high-altitude natives (Nepalese Sherpa) exhibit similar cardiovagal responses at altitude, and 3) bradyarrhythmias at altitude are partially chemoreflex mediated. Participants were grouped as Lowlanders ( n = 14; age = 27 ± 6 yr) and Nepalese Sherpa ( n = 8; age = 32 ± 11 yr). Lowlanders were assessed at 344 and 5,050 m, whereas Sherpa were assessed at 5,050 m. Heart rate (HR) and rhythm (lead II ECG) were recorded during rest and voluntary end-expiratory apnea. Peripheral chemoreflex contributions were assessed in Lowlanders ( n = 7) at altitude after 100% oxygen. Lowlanders had higher resting HR at altitude (70 ± 15 vs. 61 ± 15 beats/min; P < 0.01) that was similar to Sherpa (71 ± 5 beats/min; P = 0.94). High-altitude apnea caused arrhythmias in 11 of 14 Lowlanders [junctional rhythm ( n = 4), 3° atrioventricular block ( n = 3), sinus pause ( n = 4)] not present at low altitude and larger marked bradycardia (nadir -39 ± 18 beats/min; P < 0.001). Sherpa exhibited a reduced bradycardia response during apnea compared with Lowlanders ( P < 0.001) and did not develop arrhythmias. Hyperoxia blunted bradycardia (nadir -10 ± 14 beats/min; P < 0.001 compared with hypoxic state) and reduced arrhythmia incidence (3 of 7 Lowlanders). Degree of bradycardia was significantly related to hypoxic ventilatory response (HVR) at altitude and predictive of arrhythmias ( P < 0.05). Our data demonstrate apnea-induced bradyarrhythmias in Lowlanders at altitude but not in Sherpa (potentially through cardioprotective phenotypes). The chemoreflex is an important mechanism in genesis of bradyarrhythmias, and the HVR may be predictive for identifying individual susceptibility to events at altitude. NEW & NOTEWORTHY The peripheral chemoreflex increases both parasympathetic and sympathetic drive under chronic hypoxia. We found that this evoked bradyarrhythmias when combined with apneic periods in Lowlanders at altitude, which become relieved through supplemental oxygen. In contrast, high-altitude residents (Nepalese Sherpa) do not exhibit bradyarrhythmias during apnea at altitude through potential cardioprotective adaptations. The degree of bradycardia and bradyarrhythmias was related to the hypoxic ventilatory response, demonstrating that the chemoreflex plays an important role in these findings.

Regulation of Hypothalamo-Pituitary-Adrenocortical Responses to Stressors by the Nucleus of the Solitary Tract/Dorsal Vagal Complex.

Hindbrain neurons in the nucleus of the solitary tract (NTS) are critical for regulation of hypothalamo-pituitary-adrenocortical (HPA) responses to stress. It is well known that noradrenergic (as well as adrenergic) neurons in the NTS send direct projections to hypophysiotropic corticotropin-releasing hormone (CRH) neurons and control activation of HPA axis responses to acute systemic (but not psychogenic) stressors. Norepinephrine (NE) signaling via alpha1 receptors is primarily excitatory, working either directly on CRH neurons or through presynaptic activation of glutamate release. However, there is also evidence for NE inhibition of CRH neurons (possibly via beta receptors), an effect that may occur at higher levels of stimulation, suggesting that NE effects on the HPA axis may be context-dependent. Lesions of ascending NE inputs to the paraventricular nucleus attenuate stress-induced ACTH but not corticosterone release after chronic stress, indicating reduction in central HPA drive and increased adrenal sensitivity. Non-catecholaminergic NTS glucagon-like peptide 1/glutamate neurons play a broader role in stress regulation, being important in HPA activation to both systemic and psychogenic stressors as well as HPA axis sensitization under conditions of chronic stress. Overall, the data highlight the importance of the NTS as a key regulatory node for coordination of acute and chronic stress.

Metastatic neuroendocrine carcinoma of aortic body origin in a cat.

An 8-year-old, female spayed Domestic Shorthair cat was presented to the Auburn University Emergency and Critical Care service for evaluation of pleural effusion and a suspected intrathoracic mass. Computed tomography was performed which confirmed the presence of a large intrathoracic mass, likely heart-based. Fine-needle aspirates were obtained and a cytologic diagnosis of a neuroendocrine tumor was made. Treatment with toceranib phosphate was briefly attempted at home by the owners. The cat died at home approximately 6 weeks after diagnosis. Necropsy and subsequent histopathologic examination revealed a metastatic neuroendocrine carcinoma of aortic body origin. Aortic body tumors are extremely rare in cats and to the authors' knowledge, a neuroendocrine carcinoma of aortic body origin with distant metastases has not yet been reported in a cat.

Paragangliomas of the Head and Neck.

Paragangliomas of the head and neck are rare vascular skull-base tumors derived from the paraganglionic system with an estimated incidence of 1:30,000 accounting for 3% of all paragangliomas. The most common paraganglioma locations of the head and neck in descending order are the carotid body, jugular, tympanic, and vagal paragangliomas. This article discusses the clinical characterics, normal anatamy, imaging findings and protocols, pathology, staging, and differential diagnosis for paragangliomas of the head and neck.

18F-FDG PET/CT in a Patient With Glomus Vagale Paraganglioma and Eisenmenger Syndrome: Searching for the Missing Link?

There is emerging evidence linking cyanotic heart disease and pheochromocytoma-paraganglioma through a proposed hypoxia pathway. We present a 59-year-old woman with known Eisenmenger syndrome secondary to delayed diagnosis of ventricular septal defect, in whom F-FDG PET/CT provided comprehensive evaluation of both an F-FDG-avid left glomus vagale paraganglioma and also increased right ventricular myocardial glucose metabolism in response to severe pulmonary hypertension in the chronic shunting state.