Renovascular hypertension secondary to renal artery compression by diaphragmatic crura

Renovascular hypertension - a primer for the radiologist

Renovascular hypertension (RVHT) is an important cause of secondary hypertension, accounting for approximately 75% of cases. This pictorial review describes the imaging modalities used to diagnose RVHT, including ultrasound, computed tomography angiography, and magnetic resonance angiography, provides their benefits and limitations, and explores the imaging findings, diagnostic criteria, and management of multiple causes of RVHT. Atherosclerosis is the most common cause of RVHT, particularly in older individuals, while fibromuscular dysplasia is more prevalent in younger females. Less common discussed etiologies include polyarteritis nodosa, extrinsic compression, Page kidney, dissection, renal artery (RA) thrombus, and RA aneurysms. This paper also highlights the importance of recognizing anatomical variants and rare conditions that can impact diagnosis and management. While RVHT represents a minority of hypertension cases, its potential reversibility makes accurate diagnosis crucial. Treatment approaches vary based on etiology and may include medical management, angioplasty, stenting, or surgical intervention. This review aims to enhance radiologists' understanding of RVHT, facilitating improved diagnosis and patient care.

Under pressure: a head-to-toe review of vascular compression syndromes

Vascular compression syndromes are a group of conditions resulting from mechanical compression of blood vessels by adjacent structures leading to compromised blood flow and various associated symptoms. They frequently affect young, otherwise healthy individuals and are often underdiagnosed due to their rarity and vague clinical manifestations. Achieving an accurate diagnosis depends on the integration of clinical presentation and imaging findings. Imaging modalities including color doppler ultrasound, computed tomography angiography, magnetic resonance angiography, and catheter-directed digital subtraction angiography are essential for diagnosis and management. Dynamic imaging is crucial in eliciting findings due to the positional nature of many of these syndromes. In this paper, we will present a "head-to-toe" overview of vascular compression syndromes including Vascular Eagle Syndrome, Vascular Thoracic Outlet Syndrome, Quadrilateral Space Syndrome, Hypothenar Hammer Syndrome, Median Arcuate Ligament Syndrome, Renal Artery Entrapment Syndrome, Left Renal Vein Compression/Nutcracker Syndrome, May-Thurner Syndrome, Adductor Canal Syndrome, and Popliteal Artery Entrapment Syndrome. Treatment is variable but typically involves a combination of conservative and surgical management. Surgical approaches focus on decompression of affected neurovascular structures. Endovascular treatment alone is rarely recommended. We aim to equip general radiologists with the knowledge needed to accurately diagnose patients with vascular compression syndromes, allowing for timely treatment.

A Nine-year-old Boy with Renovascular Hypertension: Knowing Where to Look

Renal artery entrapment (RAE) by hypertrophic diaphragmatic crura is an extremely rare cause of renovascular hypertension (RVH). Here, we report the case of a 9-year-old boy diagnosed with RVH caused by right RAE by a hypertrophic diaphragmatic crus and successfully managed with close medical monitoring. Diagnosis of this entity is easily overlooked if the optimal views are not obtained during imaging, which depends on a high index of suspicion. We would like to remind clinicians to keep this rare condition in mind when evaluating children with RVH.

Renal Artery Stenosis Due to Entrapment ()

BACKGROUND

Common etiologies of renovascular occlusive disease include atherosclerosis disease, developmental fibrotic conditions such as fibromuscular dysplasia (FMD), vasculitis. Extrinsic compression of the renal artery is a rarely reported phenomenon but can lead to similar clinical manifestations.

METHODS

We report recent experience with two patients who presented with extrinsic renal artery compression due to entrapment. Diagnosis was made with a constellation of findings on computed tomography angiography, dynamic duplex sonography, and catheter angiography. Both patients had hypertension and one had downstream subsegmental renal infarcts. The patients, both with right sided renal artery entrapment, were treated with open surgical decompression. Exposure was achieved via extended Kocher maneuver followed by mobilization of the right kidney and, in one patient, detachment of the right lobe of liver to allow circumferential exposure of the proximal right renal artery to the aorta. All entrapping tissue was circumferentially released.

RESULTS

Both operations were uncomplicated. Intraoperative sonography was used to confirm luminal patency of the released segments. Follow-up renal artery duplex in both patients demonstrated resolution of dynamic compression. Renal artery peak systolic velocity and accelerations indices were all within normal limits. In both patients, improvement in blood pressure control was noted and discontinuation of anticoagulation was possible in the patient who had recurrent episodes of renal infarct.

CONCLUSION

Extrinsic compression of renal artery by diaphragmatic crura is rare but should be considered in younger patients or otherwise any patients with no vascular risk factors when renovascular hypertension workup yields no demonstrable intrinsic disease. A high index of suspicion should be raised when an anomalously high origin of the renal artery or proximity to the diaphragmatic crura are seen on cross sectional imaging. Work-up should include dynamic imaging to assess compression of renal arteries during expiration. Open surgical or laparoscopic decompression of the involved renal arteries can be curative.

Renovascular Compression by the Diaphragmatic Crus: A Case Report

Renovascular hypertension (RVHT) is among the most prevalent causes of treatment-resistant hypertension. Mostly it is caused by renal artery stenosis (RAS). With atherosclerosis being the most common cause of RAS, RAS due to external compression by the diaphragmatic crus is rare. The treatment of rare causes requires individualization due to the differences between their etiologies. Herein, we present a case of an 18-year-old patient presenting with high blood pressure readings. On follow-up, he was diagnosed with hypertension. On further evaluation, the right diaphragmatic crus compressed the right renal artery.

This case emphasizes medical management in patients with hypertension secondary to diaphragmatic crus compression, and radiological findings in such cases.