Department of Clinical Imaging and Interventional Radiology, Apollo Multispecialty Hospitals, 700054 Kolkata, West Bengal, India

*Corresponding author:Hena Parvin, Department of Clinical Imaging and Interventional Radiology, Apollo Multispecialty Hospitals, 700054 Kolkata, West Bengal, India, Email Id: drhena_p@apollohospitals.com

Copyright:© 2024 Parvin H, et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Article Information:Submission: 04/04/2024; Accepted: 29/05/2024; Published: 05/06/2024

Congenital pelvic arteriovenous malformation (AVM) is an uncommon vascular anomaly characterized by direct connection between arteries and veins, encompassing a malformed vascular network, or nidus. Due to its infrequent occurrence and the nonspecific nature of its symptoms, congenital pelvic AVM in males has been seldom explored. In this case study, we discussed a 64-year-old male who visited the gastroenterology outpatient department at Apollo Multispecialty Hospitals, Kolkata, reporting a mild, dull aching pain on the right side of his abdomen for the past five months. A high-flow pelvic wall AVM was identified through CECT whole abdomen. Absence of any other contributing pathology indicated congenital origin of AV malformation.

Keywords:Arteriovenous Malformation; Pelvic Wall AVM; Vascular Malformation; Venous Malformation; Interventional Radiology

AVM: Arteriovenous Malformation; CECT: Contrast Enhanced Computed Tomography; USG: Ultrasonography; MIP: Maximum Intensity Projection

Arteriovenous malformation (AVM) represents a vascular anomaly characterized by the connection of arteries and veins through a nidus of dysplastic vascular channels [1]. Among these, pelvic wall AVMs are particularly uncommon, with an even rarer occurrence in male patients [2,3]. The majority of pelvic AVMs arise secondary to trauma, previous surgeries, or tumours, making congenital pelvic AVMs in males exceedingly rare [4]. These malformations typically involve bone and soft tissues of the pelvic wall, draining into the branches of the internal iliac veins. Over time, as they grow, arteries and veins from the pelvic organs may also become involved. In addition to collateral from adjacent visceral branches, pelvic wall AVMs are usually fed by a multitude of vessels including branches of pudendal, obturator, and gluteal arteries, potentially reaching substantial sizes and flow rates.The clinical presentation of pelvic AVMs is varied and nonspecific [5-8]. Some individuals may remain asymptomatic, with the diagnosis only made incidentally during cross-sectional imaging of the pelvis for unrelated reasons.

This case report details a rare presentation of a congenital pelvic AVM in a male patient, who reported nonspecific symptoms such as dull aching abdominal pain. A CECT of the whole abdomen ultimately revealed a high-flow arteriovenous malformation on the right side of the pelvic wall.

A 64-year-old male visited the gastroenterology outpatient department at Apollo Multispecialty Hospitals, Kolkata, reporting a mild, dull ache on the right side of his abdomen. The pain was persistent for last five months. An ultrasound of the whole abdomen, previously performed at an external peripheral centre, showed no significant findings. Physical examination did not uncover any notable

abnormalities, and his vitals were stable. The patient had a history of type 2 diabetes mellitus for which he was under medication. He also mentioned self-administering over-the-counter pain relievers for his abdominal discomfort, though these did not provide any noticeable relief. A whole abdomen CECT was advised. It revealed, a high-flow pelvic arteriovenous malformation on the right side, with an illdefined nidus just adjacent to the right seminal vesicle. It wasfed by multiple very small calibre arterial channels arising from the anterior branch of the right internal iliac artery, with a large dilated, tortuous draining vein, showing early opacification and ending into the right internal iliac vein [Figure 1].

Pelvic congenital arteriovenous malformations (AVMs) in males are notably rare. In 2002, Game et al. documented two cases of pelvic congenital AVMs in male patients and reviewed an additional 15 cases previously reported in the literature, with only a handful more cases identified since then [9]. We discuss a scarce instance of a male patient diagnosed with a congenital pelvic AVM via CECT of the whole abdomen. In AVMs, the nidus, a malformed vascular plexus formed by remnants of the capillary network, acts as an intermediary between arterial and venous systems. While AVMs can develop in any body part, they are most commonly found in the brain, neck, kidneys, and lungs, with pelvic AVMs, particularly in males, being exceedingly uncommon [10,11].

The symptoms associated with pelvic AVMs lack specificity and range from subtle to vivid, potentially leading to lethal outcomes. They include flank, abdominal, or pelvic pain, hematuria, hemospermia, impotence, dysuria, and dyspnea due to high-output heart failure, among others [12,13]. Additionally, foot drop resulting from nerve compression and lower extremity edema caused by proximal iliac vein compression have been described [5-8]. The rarity of the condition, combined with the nonspecific nature of its symptoms, complicates early clinical diagnosis. Significant indicators of pelvic AVM include palpating a pulsatile mass and detecting loud or harsh noises upon physical examination, though deep pelvic AVMs are not palpable. In contrast to previous literature, few studies show the application of Doppler and USG is also a potential tool of solid diagnostic value for congenital pelvic AVM in males [14,15]. In the case we present, the patient experienced mild, dull aching pain on the right side of his abdomen for several months. Initial physical examinations and an ultrasound of the whole abdomen showed no abnormalities. A CECT of the whole abdomen was performed to exclude any sinister pathology, revealing a high-flow pelvic arteriovenous malformation, presumed to be congenital due to the absence of other significant contributory pathologies.

Treatment for congenital pelvic AVM in males varies based on the severity of symptoms. Lesions that are asymptomatic or mildly symptomatic may not require intervention. In this case, the patient was presented with various treatment options if his symptoms would intensify. Treatments for AVM in males have included ligation of afferent arteries, lesion excision, embolization, and surgical approaches. Surgical intervention often leads to complications such as haemorrhage, damage to adjacent organs, and recurrence, making it less favourable. Embolization, offering lower morbidity, mortality, and invasiveness, is preferred.Slow-flow VMs (venous and lymphatic

malformations) are often treated by sclera therapy [16-18].Our patient was offered embolization under fluoroscopy guidance as the treatment modality. However, he opted against definitive treatment, choosing instead a conservative ‘wait and watch’ approach.

Congenital pelvic arteriovenous malformation (AVM) is an uncommon vascular anomaly characterized by direct connections between arteries and veins, encompassing a malformed vascular network, or nidus. Only a few cases are reported in males. This case report details presentation of a congenital pelvic AVM in a 64-yearold male patient, who reported nonspecific symptoms such as dull aching abdominal pain. A CECT of the whole abdomen ultimately revealed a high-flow arteriovenous malformation on the right side of the pelvic wall.

•Congenital pelvic wall arteriovenous malformation is a rare entity, rarer in males.
• The symptoms associated with pelvic AVMs are mostly nonspecific and include flank, abdominal, or pelvic pain, haematuria, hemospermia, impotence, dysuria, dyspnoea due to high-output heart failure, foot drop, and lower extremity edema.
• Sometimes it’s an incidental finding.
• Treatment for congenital pelvic AVM in males varies based on the severity of symptoms.

The authors would like to thank Dr. Usha Goenka, director and head, of the department of clinical imaging and interventional radiology in Apollo multispecialty hospitals, for reviewing the case and Mr. Susil Das, senior CT technologist, for volumetric reformation of the CECT images. Author would also like to thank Dr. Mofasser Mallick, Group leader scientist, KIT, Germany for editing and reviewing the report.

The authors certify that they have obtained all appropriate patient consent.