Clinical characteristics and factors associated with coronary stenosis proximal to a myocardial bridge: a retrospective study

Diagnostic Ability of Perivascular Fat Attenuation Index in Predicting Atherosclerotic Plaque Formation Proximal to Myocardial Bridging of the Left Anterior Descending Artery within 3 Years

RATIONALE AND OBJECTIVES

This study was designed to investigate the association between the perivascular fat attenuation index (FAI) and atherosclerotic plaque formation proximal to myocardial bridging (MB) of the left anterior descending artery (LAD) within 3 years.

MATERIALS AND METHODS

LAD-MB patients who underwent coronary computed tomography angiography at least twice between January 2016 and December 2022 were retrospectively included in this study. In total, 99 LAD-MB patients were included in the study. Based on the formation of atherosclerotic plaques proximal to LAD-MB during follow-up, the patients were classified into two groups: LAD-MB with plaque formation and LAD-MB without plaque formation within 3 years. The anatomical features, clinical factors, and proximal perivascular FAI of LAD-MB were measured and recorded. The association of the previously mentioned factors with the presence of atherosclerotic plaque proximal to LAD-MB was determined.

RESULTS

The results showed that MB length, MB stenosis, and the perivascular FAI were significant predictors of the formation of atherosclerotic plaques proximal to LAD-MB. The area under the curve of the combined predictive model incorporating MB length, MB stenosis, and the perivascular FAI was 0.901(95% confidence interval: 0.824-0.952), with higher diagnostic performance than any other single parameter (all P < 0.05). Moreover, dynamic changes in the perivascular FAI of the vascular segments proximal to LAD-MB were higher in high-risk plaques than in non-high-risk plaques (P = 0.003).

CONCLUSION

The combined use of the perivascular FAI, MB length, and MB stenosis may enable prediction of the probability of atherosclerotic plaque formation proximal to LAD-MB within 3 years. Dynamic changes in perivascular FAI were associated with the vulnerability of plaques proximal to LAD-MB.

Surgical intervention of myocardial bridge combined coronary artery disease: could a combination of supra-arterial myotomy and CABG be a better option?

BACKGROUND

The treatment of coronary artery disease combined with severe atherosclerotic stenosis proximal to a left anterior descending artery myocardial bridge (LAD-MB) is still controversial. This study aimed to analyze the outcomes of surgical intervention in patients with severe atherosclerotic stenosis proximal to a LAD-MB.

METHODS

We retrospectively reviewed all patients with coronary artery disease combined with severe atherosclerotic stenosis proximal to the LAD-MB. The enrolled criteria were systolic compression of LAD more than or equal to 50% and atherosclerotic stenosis proximal to the LAD-MB more than or equal to 70%. All patients suffered from anginal symptoms refractory to medical therapy. All patients received supra-arterial myotomy and coronary artery bypass grafting (CABG) procedures. Clinical characteristics, intraoperative findings, and postoperative outcomes were evaluated.

RESULTS

Between 2004 and 2021, sixteen patients underwent supra-arterial myotomy and CABG procedure. The compression and length of LAD-MB were 63 ± 17.9% and 25.9 ± 16.3 mm, respectively. Of the 16 patients, one patient had a LAD-MB and proximal coronary stenosis, and 15 patients had LAD-MBs and multivessel lesions. All patients survived and recovered uneventfully without in-hospital mortality or severe complications. The median transfusion amount of red blood cells in the operation was 2 units, and no patients required unplanned reoperation for bleeding. The average length of intensive care unit stay was 2.74 days. Fifteen patients were followed up for 6-146.1 months (mean 45.3 ± 42.9 months). One patient had a recurrence of angina pectoris one year after surgery, and 14 patients had no symptoms of myocardial ischemia during the follow-up period. Significant improvement in symptoms and quality of life using the Seattle Angina Questionnaire assessment was observed in all five categories after surgery (p < 0.01).

CONCLUSIONS

Based on the results, supra-arterial myotomy and concomitant bypass surgery may be a better option for the treatment of LAD-MB combined with severe proximal stenosis.

Impact of myocardial bridge on non-culprit vessel lumen changes in patients with acute coronary syndrome

This study aims to clarify the impact of myocardial bridge (MB) on the presence and progression of atherosclerosis in left descending coronary artery (LAD) in patients with acute coronary syndrome (ACS). Ninety-eight patients who underwent percutaneous coronary intervention with the diagnosis of ACS and follow-up coronary angiography but had no significant stenosis in the LAD were included. MB was defined based on coronary angiography. Quantitative coronary angiography was performed to determine the segments where MB was present and proximal to the MB (proximal segment) in patients with MB. In patients without MB, a corresponding region was quantitatively analyzed. The primary endpoint was changes in minimum lumen diameter (MLD) and percentage of diameter stenosis (%DS) in the proximal segment from baseline to follow-up angiography, namely ΔMLD and Δ%DS. MB was identified in 29 (29.6%) patients. Patients with MB had larger MLD and smaller %DS in the proximal segment than their counterpart. During the mean follow-up period of 12.9 ± 5.7 months, MLD and %DS in the proximal segment did not change significantly from baseline to follow-up in patients with and without MB. No significant between-group differences were observed in ΔMLD and Δ%DS. Baseline MLD was identified as the only factor associated with ΔMLD in the proximal segment. ACS patients who had MB but no significant stenosis in the LAD had larger MLD and smaller %DS at the segment proximal to MB compared to those without. In this selected population, serial lumen changes assessed by ΔMLD were not associated with the presence of MB in the LAD.

Relationship between Different Degrees of Compression and Clinical Symptoms in Patients with Myocardial Bridge and the Risk Factors of Proximal Atherosclerosis

OBJECTIVE

To explore the relationship between different degrees of compression and clinical symptoms in patients with the myocardial bridge and the risk factors of proximal atherosclerosis.

METHODS

The clinical data of 156 patients with the myocardial bridge who underwent selective coronary angiography in our hospital from December 2010 to December 2015 were collected. The patients were divided into Noble grade I group (102 cases) and Noble grades II-III group (54 cases) according to the degree of mural coronary artery systolic stenosis. According to the results of coronary angiography, 156 patients with the myocardial bridge were divided into an atherosclerosis group (the myocardial bridge combined with atherosclerosis at the proximal end of the myocardial bridge of simple wall coronary artery), 91 cases, and a control group (isolated myocardial bridge), 65 cases. The relationship between different degrees of compression and clinical symptoms in patients with the myocardial bridge was observed, and the logistic regression model was used to analyze the risk factors of proximal atherosclerosis in patients with the myocardial bridge.

RESULTS

The incidence of atherosclerotic stenosis, angina pectoris, and myocardial infarction in the proximal part of the myocardial bridge in the Noble grades II-III group was higher than that in the Noble grade I group (P < 0.05). The differences in age, hypertension, and Noble classification between the two groups were statistically significant (P < 0.05). The differences of total cholesterol (TC) and C-reactive protein (CRP) between the two groups were statistically significant (P < 0.05). Multivariate analysis showed that age, hypertension, Noble grade, and CRP were all risk factors for proximal atherosclerosis in patients with the myocardial bridge (P < 0.05).

CONCLUSION

The more severe the compression of the myocardial bridge, the greater the risk of cardiovascular events for patients and the higher the incidence of atherosclerotic stenosis in the proximal part of the myocardial bridge. In addition, the occurrence of atherosclerosis in the proximal coronary artery of the myocardial bridge may be affected by age, hypertension, Noble grade, and CRP level.