Left renal vein compression between the aorta and the superior mesenteric artery at an acute angle of the origin of the latter (“the nutcracker syndrome”) often leads to phlebohypertension in the left renal vein causing a combination of structural and functional changes in the kidneys and pelvic organs, different clinical manifestations such as left-sided varicocele, hematuria, pelvic venous congestion syndrome, the development of renal failure.
The objective of the research: to determine indications for surgical and conservative treatment of aorta mesenteric compression.
Materials and methods. The study included 210 patients (142 men and 68 women) with suspected “nutcracker syndrome” who were referred to vascular surgeons for a consultation by urologists and gynecologists during the period from 1999 to 2020, mainly from the western regions of Ukraine (about 11 million population). The age of the patients ranged from 12 to 52. All patients were interviewed for specific complaints: pain in the left lumbar region and left half of abdomen, inability to eat large amounts of food, hematuria, proteinuria, hemospermia, erectile dysfunction, left sided varicocele in men, and left sided pudendal varicosity and dysmenorrhea in women. All referred patients with suspected “nutcracker syndrome” underwent color Doppler ultrasound to determine the presence of pathological reflux in the left renal and gonadal veins by measuring peak systolic velocities in order to confirm or exclude that pathology. The patients with confirmed left renal vein stenosis underwent CT angiography.
Results. According to color Doppler ultrasound, different degree of aorta mesenteric compression was confirmed in 138 (65.7%) patients (83 men and 55 women), critical left renal vein stenosis was observed in 35 of them. Two patients were diagnosed with the retroaortic left renal vein (“posterior nutcracker”).
According to observations, clinical manifestations of AMC syndrome severe forms occurred in case of an increase in the diameter of the distal part of the LRV compared to its proximal segment by 3-6 times as well as in case of an increase in peak systolic velocity in the stenosed proximal segment by 6-14 times (by 8.7 times on average) compared to the left renal vein distal segment.
Conclusions. Color Doppler ultrasound with determination of peak systolic velocities and diameters of the left renal and gonadal veins, pathological reflux in them must be the obligatory diagnostic stage in the patients with suspected AMC. The choice of treatment approach should be made taking into account clinical and laboratory indices, as well as the assessment of AMC severity according to instrumental data (ultrasound, CT angiography, MRA, etc.). The severity of pathomorphological changes in the pelvic organs and their consequences proves the need to eliminate phlebohypertension in the left renal and gonadal veins. LRV transposition proves its effectiveness in the remote postoperative period.
Asymptomatic nutcracker phenomenon: entrapment of the left renal vein shown by CT without left flank or pelvic pain, or macroscopic haematuria
