Monosodium Urate Crystal Deposition in Coronary Artery Plaque by 128-Slice Dual-Energy Computed Tomography: An Ex Vivo Phantom and In Vivo Study

Abstract

ObjectiveMonosodium uric acid (MSU) crystals may accumulate in the coronary plaque. The objective was to assess whether dual-energy computed tomography (DECT) allows for detection of MSU in coronary plaque.MethodsPatients were examined with 128-slice DECT applying a cardiac electrocardiogram-gated and peripheral extremity protocol. Patients were divided into 3 groups: gout (tophi >1 cm in peripheral joints), hyperuricemia (>6.5 mg/dL serum uric acid), and controls. The groups were matched for cardiovascular risk factors. Monosodium uric acid–positive (+) and calcified plaque were distinguished, and the coronary artery calcium score was calculated. Ex vivo phantom: MSU solutions were diluted in different NaCL solutions (5%/10%/15%/20%/25%). Coronary artery models with 2 different plaque types (MSU+ and calcified) were created.ResultsA total of 96 patients were included (37 with gout, 33 with hyperuricemia, and 26 controls). Monosodium uric acid–positive plaques were found more often in patients with gout as compared with controls (91.9% vs 0.38%; P < 0.0001), and the number of plaques was higher (P < 0.0001). Of 102 MSU+ plaques, 26.7% were only MSU+ and 74.2% were mixed MSU+/calcified. Monosodium uric acid–positive plaque had mean 232.3 Hounsfield units (range, 213–264). Coronary artery calcium score was higher in patients with gout as compared with controls (659.1 vs 112.4 Agatston score; P < 0.001). Patients with gout had more MSU+ plaques as compared with patients with hyperuricemia (91.6% vs 2.9%; P < 0.0001), and coronary artery calcium score was higher (659.1 vs 254 Agatston score; P < 0.001), but there was no difference between patients with hyperuricemia and controls. Ex vivo phantom study: MSU crystals were detected by DECT in solutions with a concentration of 15% or greater MSU and could be distinguished from calcified.ConclusionsCoronary MSU+ plaques can be detected by DECT in patients with gout.

Dual-energy computed tomography in crystalline arthritis: knowns and unknowns

“…These deposits were found in patients with the highest calcium scores. The same results were found by the same group in a similar study separating the control group into hyperuricemic and nonhyperuricemic controls [23]. Our group provided conflicting data from a study of popliteal artery plaques in 126 gout patients and 26 controls, showing that MSU-coded plaques were equally prevalent between groups [24 ▪▪ ].…”

Detection of monosodium urate depositions and atherosclerotic plaques in the cardiovascular system by dual-energy computed tomography

“…In recent years, along with the improvement of living standards and changes in diet, the content of serum MSU in the population has been increasing [ 10 ]. At present, most studies on gout using DECT focus on peripheral joints, such as the metatarsophalangeal joint, knee joint, sacroiliac joint, and wrist joint, and there are few studies on the deposition of MSU crystals in the cardiovascular system [ [23] , [24] , [25] ]. Several clinical studies confirmed a correlation between gout and the incidence of CVD [ [10] , [11] , [12] , [13] , [14] , [15] , [16] , [17] , [18] , [19] ].…”

“…In a study in 2019, Klauser et al [ 23 ] first proposed that there could be MSU deposition in the coronary arteries and proved this view by autopsy. Then, in 2020, Feuchtner et al [ 24 ] also proved that there was MSU deposition in the coronary arteries by establishing a model of MSU deposition in the coronary artery.…”

“…Some studies have attempted to detect urate deposition in coronary plaque using DECT without definite proof. Recently, several articles reported that DECT detects coronary MSU plaque in patients with gout or hyperuricemia [ [23] , [24] , [25] ]. MSU deposition is closely associated with coronary artery diseases [ 23 ], but there are few clinical studies about urate deposition plaque in coronary heart diseases [ 23 , 24 ].…”

Hyperuricemia predicts increased cardiovascular events in patients with chronic coronary syndrome after percutaneous coronary intervention: A nationwide cohort study from Japan

“…In the CARDIA study, a cohort of young subjects showed that the elevation of SUA levels might be a biomarker for early atherosclerosis, as assessed by coronary artery calcified plaque and carotid intima-media thickness ( 33 ). A recent study using dual-energy computed tomography detected coronary monosodium uric acid crystal deposition in gout patients ( 34 ). However, some studies showed that higher SUA levels were not significantly linked to a higher rate of cardiovascular mortality in CAD patients.…”