Carotid Body Research Articles (Page 1)

Paraganglioma (PGL) is a general term for tumors that originate in the paraganglia in dogs, most commonly reported in the carotid and aortic bodies. Reports on surgical treatment are rare because these tumors develop near large blood vessels, and their prognosis remains unclear. In dogs, the indications for and safety of surgical procedures involving the celiac artery (CA) root and the dissection of its major branches have not been established. To the best of our knowledge, this is the first reported case of CA root involvement in canine PGL. Surgery was performed on day 84 to remove a PGL tumor. The mass was firmly attached to the left lobe of the pancreas, portal vein, CA, and cranial mesenteric artery (CMA). Therefore, a combined resection was performed, including the spleen, left lobe of the pancreas, and left hepatic lymph nodes. Among the main branches of the CA, the splenic and left gastric arteries could not be separated and were transected. Consequently, the stomach wall became ischemic, and reduced pulsation of the left gastric and omental arteries was observed. To maintain blood supply, the common hepatic artery was preserved. After normalization of the stomach wall color, the CMA was separated from the mass, and the tumor was removed. Pathological examination confirmed that the mass was a PGL, with no metastasis to the hepatic lymph nodes. A computed tomography scan on day 265 revealed that blood flow in the common hepatic artery, portal vein, and left gastric region was well maintained. As of day 279, there was no evidence of metastasis or recurrence, and the patient remained in good condition. In this case, the main branches of the CA, except for the common hepatic artery, were transected to remove the mass; however, the patient was discharged without serious complications. This is attributable to recovery of blood flow from collateral routes. Considering this blood flow recovery and that intraoperative gastric ischemia was temporary, complete ligation of the CA root may be acceptable in some cases. Additionally, the prognosis for PGL was favorable when complete resection was achieved.

Head and neck paragangliomas (HNPGLs) are rare neuroendocrine tumors and often arise in the head and neck. Due to their localization, the tumor and its surgical treatment pose a risk for cranial nerve impairments. Few studies have focused on the health-related quality of life (HRQOL) in patients with HNPGLs and their relation to tumor localization. In patients (n = 125) treated with primary surgery for HNPGLs between 2006 and 2023, clinical data was obtained. Long-term QOL was assessed with the validated German version of the EORTC QLQ-H&N43 with a mean follow-up since surgery of 6.0 years. Most common were carotid body PGLs (n = 78; 62.4%) including Shamblin I (n = 25), II (n = 42) and III (n = 9) along jugular (n = 31; 24.8%) and vagal (n = 10; 8.0%) tumors. In the QLQ-H&N43, the scales fear of progression (41.2), coughing (33.9), neurological problems (22.4), sexuality (21.4), and swallowing (21.2) showed the highest mean scores. Jugular and vagal tumors showed higher symptom levels compared to carotid body tumors, especially Shamblin I. Surgical treatment of PGLs may lead to significant impairments in physical and psychological domains, especially in larger carotid body, vagal and jugular tumors. Structured pre- and postoperative cranial nerve examinations and interprofessional support should be provided to mitigate postoperative QOL reduction.

Background: Carotid body tumors (CBTs), or paragangliomas, are rare, highly vascular neuroendocrine neoplasms arising at the carotid bifurcation. Though generally benign and slow-growing, their close association with critical neurovascular structures, including the carotid arteries, presents complex diagnostic and therapeutic challenges with significant cardiovascular implications. Case Presentation: A 66-year-old female presented with a right-sided neck swelling of 3 months’ duration, accompanied by intermittent dull headaches and episodic sweating. Physical examination revealed a 7×4 cm firm, expansile mass in the right carotid triangle, mobile horizontally, with palpable pulsations and intact cranial nerve function. Imaging with CT angiography, contrast-enhanced MRI, and digital subtraction angiography demonstrated a highly vascular, enhancing mass at the carotid bifurcation causing splaying of the internal and external carotid arteries—characteristic of a carotid body tumor. Additionally, enlarged right cervical lymph nodes suggestive of paragangliomas were noted. Intervention: The patient underwent successful surgical excision of the tumor via a transcervical approach. Intraoperative vascular control was critical to prevent hemorrhage and preserve cerebral perfusion. Histopathology revealed nests of round to oval cells with eosinophilic cytoplasm arranged in a “zellballen” pattern, confirming paraganglioma. Outcome: Postoperative recovery was uneventful without neurological deficits. The patient remains under close follow-up for surveillance. Conclusion: This case underscores the significance of early vascular imaging and a multidisciplinary approach in managing carotid body tumors. Given the tumor’s direct involvement with carotid arteries and the potential for vascular complications, cardiovascular specialists must be engaged in diagnosis, surgical planning, and perioperative care. Surgical resection remains the definitive treatment, with histopathology confirming diagnosis. Vigilant long-term follow-up is essential due to the tumor’s proximity to critical neurovascular structures and potential syndromic associations.

TRPV4 (transient receptor potential vanilloid 4) is a non-selective, multifunctional cationic channel that is expressed in numerous cells in the body. It can be activated by temperature, mechanical forces, and chemical and biochemical molecules. Functionally, TRPV4 participates in maintaining osmotic homeostasis, blood pressure, and hypoxic preconditioning. As far as we know, the presence of TRPV4 has never been reported in the carotid body despite the overlap that exists between some biological functions of TRPV4 and the physiology of the carotid body. In the present work, immunofluorescence associated with confocal laser microscopy, associated with quantitative analysis (area occupied by immunofluorescence), has been used to examine the occurrence of TRPV4 in the human carotid body. The results demonstrated the presence of TRPV4 in a subpopulation of chemoreceptor type I cells (approximately 65–68%), a subpopulation of type II supporting cells, and in nerve terminals in the human carotid body. Its function, if any, in this multisensory organ must be demonstrated, but it is in line with the functions attributed to the carotid body.

BackgroundCarotid body (CB) ablation can reduce sympathetic activity and blood pressure but impair the body's ability to regulate hypoxia. This study explores the efficacy and safety of using microbubble contrast agents combined with high mechanical index diagnostic ultrasound irradiation (HMIUI) to modulate CB activity in treatment of hypertension in rabbits.MethodsObese hypertensive rabbits were randomly divided into three groups: unilateral intervention group (UIG, n = 6), bilateral intervention group (BIG, n = 10), and control group (CG, n = 7). Rabbits received intravenous injection of sulfur hexafluoride microbubbles for 15 min, and irradiation at the carotid bifurcation by continuous diagnostic ultrasound FLASH mode simultaneously. Blood pressure (BP), hypoxic ventilatory response (HVR), peripheral chemoreceptor sensitivity (PCS), and baroreceptor sensitivity (BRS) were measured, and values were compared with before the intervention and 1 month after. In addition, pathology and electron microscopy were used to observe the histological and ultrastructural changes of CB.ResultsIn both UIG and BIG groups, systolic and diastolic blood pressure significantly decreased compared to pre-intervention (p < 0.05). Compared to the control group, the BIG group showed a decrease of 10 mmHg exceeding in systolic and diastolic blood pressures. HVR and PCS decreased by nearly 50% from pre-intervention. Changes in CB injury and fibrous tissue proliferation were found by Histological. TUNEL assay showed varying degrees of apoptosis in the treated CB, and immunofluorescence confirmed the reducing expression of type I and II cells.ConclusionsUltrasound microbubbles combined with HMIUI effectively modulate CB function and reduce blood pressure in an obese hypertensive rabbit model in the short term.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12938-025-01451-z.

The carotid body is a peripheral chemoreceptor that consists of clusters of chemoreceptive type I cells, glia-like type II cells, afferent and efferent nerves, and sinusoidal capillaries and arterioles. Cells and nerves communicate through reciprocal chemical synapses and electrical coupling that form a “tripartite synapse,” which allows for the process of sensory stimuli within the carotid body involving neurotransmission, autocrine, and paracrine pathways. In this network there are a variety of neurotransmitters and neuromodulators including adenosine 5′-triphosphate (ATP). Carotid body cells and nerve fibre terminals express ATP receptors, i.e., purinergic receptors. Here we used double immunofluorescence associated with laser confocal microscopy to detect the ATP receptor P2X7 and pannexin 1 (an ATP permeable channel) in the human carotid body, as well as the petrosal and cervical sympathetic ganglia. Immunofluorescence for P2X7r and pannexin 1 forms a broad cellular network within the glomeruli of the carotid body, whose pattern corresponds to that of type II cells. Moreover, both P2X7r and pannexin 1 were also detected in nerve profiles. In the petrosal ganglion, the distribution of P2X7r was restricted to satellite glial cells, whereas in the cervical sympathetic ganglion, P2X7r was found in neurons and glial satellite cells. The role of this purinergic receptor in the carotid body, if any, remains to be elucidated, but it probably provides new evidence for gliotransmission.

Elevated sympathetic nerve activity (eSNA) is a hallmark of cardiovascular disease and represents an important clinical target for disease management. A known driver of eSNA is aberrant signalling from, and sensitisation of, the carotid body (CB) arterial chemoreceptors. Sensitisation is coupled with CB hypertrophy, the cause of which remains unclear. Here, we set out to characterise the morphological basis of CB hypertrophy in hypertension to understand its aberrant activity. Using high-throughput fluorescence microscopy, we mapped the neuro-vascular interface and chemoafferent innervation of the CB of Spontaneously Hypertensive Rats (SHR) across multiple age groups.We show that CB hypertrophy driven by chemosensory (type I) cell hyperplasia and an expanded vascular network is evident in 4-6 week-old SHR without established hypertension.Specifically, CB hypertrophy in the SHR is linked to increased chemoafferent innervation and an age-dependent remodelling of nerve fibre composition. CB hypertrophy in hypertension is associated with chemosensory hyperplasia and angiogenesis, likely mediated by impaired HIF-PHD signalling in the SHR. We propose that CB size may serve as a candidate marker of chemoafferent sensitivity and the efficacy of therapies targeting the CB; However, further validation in humans is needed to support this link. Neurotrophic pathways promoting increased chemoafferent innervation in hypertension are proposed as a potential target for modulating CB activity in sympathetically mediated diseases.

Background: Carotid body tumors (CBTs) are rare neoplasms originating from the carotid body. A comprehensive synthesis of the available evidence is essential to enhance the understanding of this condition among clinicians and researchers. Purpose: This review aims to provide a comprehensive overview of CBTs, encompassing their epidemiology, pathophysiology, clinical manifestations, current treatment modalities, and associated complications. Research Design: A narrative literature review was conducted, synthesizing information from relevant studies identified through a systematic search of electronic databases. Study Sample: The review included studies focusing on human subjects with carotid body tumors, encompassing case reports, case series, cohort studies, and relevant review articles. Data Collection and Analysis: The literature search was primarily conducted in the PubMed database. The search strategy utilized a combination of keywords and Medical Subject Headings (MeSH) terms related to "carotid body tumors," "chemodectoma," and "paraganglioma." Retrieved articles were screened based on titles and abstracts, and full texts of relevant studies were reviewed for data extraction. Data on epidemiology, pathogenesis, clinical features, treatments, and complications were then thematically analyzed. Results: Epidemiological data indicate a slight increase in the global incidence of CBTs, although they remain relatively uncommon. The pathogenesis involves factors such as genetic predisposition, chronic hypoxia, and geographical influences. Clinical presentation is variable, commonly featuring neck masses, carotid sinus syndrome, and voice changes, depending on tumor size and location. Primary treatment options include surgical excision, radiotherapy, and embolization, with the choice of modality influenced by patient age, tumor size, and location. While surgery is often the preferred approach, it carries risks of complications such as cranial nerve injury, stroke, and hemorrhage. The review also identifies and discusses rare complications, including baroreceptor reflex failure. Conclusions: A thorough understanding of the multifaceted aspects of CBTs is crucial for refining diagnostic and therapeutic strategies. This integrated knowledge is expected to contribute to improved patient survival and quality of life.

Disclosure: C. Ramirez-Renteria: None. P.E. Espinosa Cardenas: None. A. Albarran: None. N.G. Lopez-Juarez: None. G.R. Manuel: None. E. Sosa: None.Background: Preoperative management with alpha or beta blockade in non-functioning pheochromocytomas (Pheo) and paragangliomas (para) remains controversial, but the pre-anaesthetic evaluation should assess all the cardiovascular risk (CVR) factors that may be present even in young patients. Aim: to describe the frequency of CVR factors in patients evaluated for non-functioning Pheo and PGN in a referral centre. Materials and methods: All the medical files of adult patients evaluated for Pheo or PGN between January 2018 and March 2025. were reviewed. We determined the frequency of traditional CVR factors and previous cardiovascular events in patients with negative hormonal tests and enough clinical information. Results: From a database of 534 patients, 165 fulfilled the inclusion criteria (we excluded 15 from a different referral centre, 39 functioning tumours, and 315 without laboratory test results). Most (91.5%) were women, with a median age of 59 years (IQR 49-68), and 83% were in the carotid body. A previous diagnosis of hypertension was present in 55.2%, and 20% were using beta blockers at the time of diagnosis. Hyperlipidemia was present in 56.1%, previous heart disease in 21.3%, prediabetes in 36.4%, diabetes in 21.8% and active tobacco use in 16.9%. Median total lipids (in mg/dL) were 171 for cholesterol (normal <200), HDL was 46 mg/dL, LDL 99 (<100) and triglycerides 123 (<150). During surgery, 31.4% had elevated blood pressure and 28.2% hypotension, 15.5% required drugs or fluids to stabilize their blood pressure, 11 patients had a cerebrovascular event after the surgery (one died) and 1 had an ischemic cardiac event. Conclusions: Patients with non-functioning Pheo/PGN have a high frequency of comorbidities related to cardiovascular disease. Proper assessment and treatment may help reduce the risk of intraoperative complications. Thorough evaluation, including hormone testing, is suggested in all patients with Pheo/para before surgery.Presentation: Saturday, July 12, 2025

Abstract Disclosure: N. Hernandez: None. G.Y. Kim: None. Background: Paragangliomas (PGLs) are neuroendocrine tumors from chromaffin tissues in sympathetic or parasympathetic ganglia. Head and neck PGLs (HNPGLs) comprise 3% of all PGLs with an incidence of 0.6 cases per 100,000 persons-years. The clinical presentation of PGLs is variable and depend on their location. Although typically asymptomatic, carotid body and vagal PGLs can present as a painless neck mass associated with dysphagia, cough, or hoarseness. HNPGLs are not commonly associated with catecholamine hypersecretion, as up to 95% are non-secretory. Diagnosis is established by anatomical localization of the tumor. Even though catecholamine secretion is rarely found with HNPGLs, biochemical testing should be done to rule out a secretory component. We present a case of a patient with bilateral carotid body PGL with unilateral catecholamine hypersecretion. Clinical Case: 38-year-old woman without significant medical or family history was seen in endocrinology clinic in 2019 with symptoms of daily right sided headache lasting for a few minutes, associated with nausea, sweating and hiccups. These episodes were triggered by positional changes of the neck. MRI revealed a T2 hyperintense right carotid space lesion measuring 4.8 x 2.4 x 3 cm and a similar lesion measuring 1.7 x 1.6 cm in the left carotid space. Biochemical work-up was positive for elevated 24-hour urine normetanephrines at 2,032 [nl. 131-612 mcg] and plasma normetanephrines at 944 [nl. 0-210 pg/mL]. MIBG scan showed abnormal, bilateral focal uptake within the neck, consistent with carotid space PGLs. Genetic testing was negative. She was started on doxazosin 2 mg and atenolol 25 mg oral daily for symptom control. She lost to follow up since 2021 and re-presented to clinic in 2024 due to recurrence of her symptoms. Repeat MRI showed interval increase in size of the right carotid PGL to 4.1 x 5.1 x 6 cm, the left PGL was stable in size. Plasma normetanephrines were elevated to 1,944 [nl. 0-210 pg/mL] with normal plasma metanephrine of 25.7 [nl. 0-88 pg/mL]. Patient underwent surgical excision of the right sided PGL. Pathology showed a 5.5 cm PGL positive for INSM1, SSTR2A and synaptophysin. On her post-op follow up, she had clinical resolution of her symptoms. Plasma normetanephrines normalized to 68.3 and 49.6 pg/mL at 1 week and 5 weeks post-op respectively. Conclusion: HNPGLs are rarely associated with catecholamine hypersecretion. The prevalence of clinically significant catecholamine secreting HNPGLs has been estimated to be 7.7%-9.2%. However, this patient has bilateral carotid body PGLs with distinct metabolic activity. This case highlights the unpredictable metabolic behavior of these tumors. The low incidence of HNPGLs underscores the importance for clinicians to keep it in the differential diagnosis when patients present with enlarging neck masses associated with symptoms of catecholamine excess or non-specific symptoms. Presentation: Monday, July 14, 2025

The bifurcation of the carotid artery is a crucial node for blood supply to the brain. External compression caused by surrounding masses can lead to severe hemodynamic disturbances and neurological abnormalities. This article reviews the pathogenesis, clinical manifestations, diagnostic methods, and treatment approaches of this condition, including the pathological characteristics of common compression lesions such as carotid body tumors and schwannomas. It compares the applicability of imaging examination methods such as ultrasound, CTA, and DSA, analyzes the suitable conditions and treatment effects of surgical removal, vascular reconstruction, and interventional therapy. The research aims to provide standardized diagnostic and treatment concepts for clinical practice, emphasizing the crucial role of individualized treatment plans in improving patient outcomes. It also looks forward to the development trend of precision medicine guided by imaging.

ATP acting on P2X3R within carotid bodies (CBs) underpins chemoreflex-mediated sympathetic overactivity in Spontaneously Hypertensive rats (SHR). Pyridoxal 5'phosphate (PLP), the active form of vitamin B6, is reported as being a non-selective P2X receptor blocker. Hence, we hypothesized that PLP antagonism of P2X3R in the CB would treat hypertension. Herein, we employed a multipronged approach to investigate PLP's capability to attenuate CB hyperexcitability in hypertension.First, PLP inhibited Ca2+ responses evoked by α, β-methylene ATP in cells lines expressing human (h) P2X3R with IC50 of 8.7µM. Next, in-silico data predicted that PLP binds to the same site of Gefapixant, supporting an allosteric antagonism. Using an isolated perfused carotid artery bifurcation-CB preparation, arterial infusion of PLP (50 µM; 15 min) attenuated CBs sensory firing in SHR (P=0.012). Using the in situ working-heart brainstem preparation, carotid artery injections of PLP (1-5mM) attenuated the chemoreflex-evoked sympathetic (P=0.023) but not phrenic (P=0.62) responses; the CB was stimulated with potassium cyanide (KCN,50 µL; 0.04%). In awake telemetered SHR (n=6), intravenous infusion of PLP (48 mg/Kg/h; 30 min) attenuated KCN-evoked chemoreflex responses and reduced systolic, diastolic, and mean blood pressures (ΔMBP = -15.6 mmHg; P=0.025). Translating our results, we performed a small double-blind randomized clinical trial. In volunteers with hypertension (n=14), oral supplementation with pyridoxine hydrochloride (600 mg) attenuated the hypoxic ventilatory response only in patients with high peripheral chemoreflex sensitivity (P=0.021). Our findings suggest that PLP binds to and antagonizes P2X3R and is a viable candidate for larger clinical trials to treat CB dysregulation in cardiovascular diseases.

Hypertension remains a leading global health challenge, affecting over 1.3 billion individuals worldwide and contributing significantly to cardiovascular morbidity and mortality. In recent years, interventional device-based therapies have emerged as promising adjuncts by targeting sympathetic overactivity and autonomic dysregulation, key mechanisms in the pathogenesis of hypertension. Currently, the use of these interventional therapies is primarily reserved for patients with resistant hypertension (RH) who remain uncontrolled despite optimal medical therapy. This review provides an overview of the evolving landscape of interventional approaches, including renal denervation (RDN), baroreceptor activation therapy (BAT), carotid body modulation, hepatic denervation, and cardiac neuromodulation. Among these, RDN has the most robust clinical trial evidence, while other neuromodulatory strategies are being evaluated in early-phase studies. Additionally, this review underscores the importance of systematically identifying and managing secondary causes of hypertension, such as primary aldosteronism, renovascular disease, and obstructive sleep apnea, before considering procedural interventions. As the field advances, these therapies may assume a more prominent role in precision-based hypertension management.

Abstract Glomus tumors, also known as paragangliomas or chemodectomas, are usually slow–growing, benign, highly vascular tumors of neuroendocrine origin. Glomus tumors (paragangliomas) represent 0.6% of neoplasms of the head and neck and 0.03% of all neoplasms. In head-and-neck region, these common paragangliomas originate from the jugular bulb, carotid body, and vagus nerve. The synchronous occurrence of carotid body and glomus jugulare tumors is infrequent. Multicentric paragangliomas are seen in 10% of sporadic patients and 30%–40% in familial forms. We report an extremely rare case of multicentric, nonfamilial, nonfunctional right glomus jugulare with bilateral carotid body tumors and the surgical management.

Abstract Surgical excision of carotid body tumors still continues to be a challenge due to multiple arterial feeders leading to hypervascularity. The hypervascularity is primarily receiving blood supply from the branches of the external carotid artery (ECA). The ascending pharyngeal artery, a branch of the ECA, is the primary feeder, but other branches such as the occipital artery, superior thyroid artery, and even the internal carotid artery or vertebral artery can contribute in some cases. The glomic artery, although rare, can contribute significantly to the hypervascularity. We present the two cases of glomic artery supplying carotid body tumor. A detailed knowledge of arterial supply with the identification of rare arterial feeders such as glomic artery helps in proper planning, avoiding cerebrovascular events during preoperative embolization and reducing perioperative bleeding.

Mechanisms underpinning peripheral chemoreceptor modulation of hypertension.

Background: Fluorescence-guided surgery (FGS) using indocyanine green (ICG) for fluorescent angiography and lymphography is well established as a safe and reproducible technique in head and neck surgery, mostly for thyroid and parathyroid surgery.Methods: We present our experience with FGS for thyroid and parathyroid gland (PG), and other complex surgeries in the head and neck region, such as major gland resections, lymph node dissections, and carotid body tumor resections, among others.Results: A total of 33 patients underwent FGS using ICG in different doses. A total of 50 PGs were identified; two carotid paragangliomas, two major salivary glands, the thoracic duct, and its right side equivalent were observed emitting fluorescence through the supraclavicular hollow. Twenty-one nerves were also observed emitting fluorescence.Conclusions: FGS proved to be an excellent tool for additional surgical-related benefits and surgical safety in head and neck surgery, especially in complex procedures.

Plasticity induced loss of apnea alarm through repeated apneas: A proposed mechanism for respiratory sudden death.

Safety and outcomes of self-expanding covered stents in carotid revascularization for Shamblin class III carotid body tumors.

Ectopic Thyroid Tissues masquerading as a carotid body mass: Report of a case with literature review