Giant Pseudoaneurysm From Vieussens' Arterial Ring

Vieussens' Arterial Ring: Historical Background, Medical Review and Novel Anatomical Classification

In coronary artery disease, the presence of Vieussens' arterial ring (VAR), a ring-shaped anastomosis between the conus branch of the right coronary artery with the left anterior descending artery (LAD), will allow blood flow to return to the obstructed coronary system. We have conducted a literature review, aiming to collect all the existing information about the documented VAR cases and any related pathological conditions. A total of 54 studies entered the review, including 56 patients. The mean age of the patients was 56.12 ± 16.2 years. Angina was present in 53.6% of the patients, with 7.2% of the cases being asymptomatic. Coronary artery disease outweighed (58.9%) as the patients' most frequent diagnosis. We propose a novel VAR anatomical classification, based on the sites of origin and termination of its course, with six distinct types, for a better understanding and surgical management of VAR. Type IA, originating from the conus branch and terminating in the proximal segment of the LAD was most frequently reported (51.8%). The recognition and the subsequent evaluation of the ring's anatomy and course are crucial for a customized clinical intervention. When right and left coronary angiographies fail to reveal any collateral circulation, selective conus artery catheterization should be in order. The proposed classification offers a manageable and comprehensive context for the assessment, evaluation and planning of therapeutic strategies of VAR and sets a new terminology frame for treatment guidelines.

Luminal diameter ratio of Vieussens' arterial ring is valuable in determining appropriate clinical management for patients with pathologic Vieussens' arterial ring

BACKGROUND

Although the adverse events of pathologic Vieussens' arterial ring (VAR) have been reported, it is difficult to determine optimal clinical management. Thus, we hypothesized that the luminal diameter ratio of VAR obtained from coronary computed tomography angiography (CCTA) could be used as a clinical tool to inform appropriate patient management.

METHOD

A total of 29 patients with pathologic VAR were retrospectively recruited for this study. The VAR luminal diameter ratio was defined as a quotient of VAR fistula divided by the orifice of RCA or LAD, based on which, patients were divided into small fistula group and large fistula group. The AUC, sensitivity, specificity, positive and negative predictive values were obtained from ROC curve. The cutoff value of the VAR luminal diameter ratio was calculated and assessed during the follow-up.

RESULTS

The VAR luminal diameter ratio of fistula/RCA orifice was 0.505 ± 0.098 in small fistula group and 1.020 ± 0.150 in large fistula group. The VAR luminal diameter ratio of fistula/LAD orifice was 0.507 ± 0.123 in small fistula group and 1.039 ± 0.151 in large group. The value was correlated with the choice of the treatment (r = 0.643 p < 0.01, r = 0.627 p < 0.01). The AUC, sensitivity, specificity, positive and negative predictive values were 0.803, 54.5%, 100%, 100% and 78.3% of the fistula/RCA orifice ratio and 0.833, 63.64%, 94.44%, 87.5% and 81.0% of the fistula/LAD orifice ratio, respectively. The cutoff values of both fistula/RCA orifice and fistula/LAD orifice ratios were 0.676.

CONCLUSIONS

The VAR luminal diameter ratio may be a valuable index to determine appropriate treatment for patients with pathologic VAR.