CT coronary angiography findings in non-atherosclerotic coronary artery diseases

Giant proximal left anterior descending aneurysm causing multi-vessel myocardial ischaemia: the pressure is on-a case report

Background

Giant coronary artery aneurysms are a rare cause of myocardial ischaemia. Due to the rarity and variety of presentation of these cases, no standardized investigation or treatment has been established for management. We report a case study of a giant proximal left anterior descending (LAD) coronary aneurysm causing myocardial ischaemia due to the pressure effect from the weight of the aneurysm as well as from a change in rheology from a 'steal effect' on both the LAD and left circumflex (LCx) arteries.

Case summary

A 55-year-old patient presents initially with a history of angina. Initial investigation with computed tomography (CT) was suboptimal, requiring invasive diagnostic angiography, which detects a giant proximal LAD aneurysm. Subsequent investigations, with CT-fractional flow reserve (FFR) and stress echocardiography (ECHO), correlated to identify multi-vessel ischaemia resulting from the aneurysm. The patient was managed with multi-disciplinary team-led surgical resection and triple coronary artery bypass grafts with good results.

Discussion

This case highlights the complexity of coronary anomalies and importance of additional functional three-dimensional imaging on top of the static computational tomography coronary angiography analysis. Together, these two complimentary investigations qualitatively enabled the assessment of anomaly with surrounding structures such that the possibility of a mass effect on the LCx artery results in a positive stress test. Furthermore, this is a novel use of CT-FFR for coronary anomalies and it demonstrated good correlation of LAD territory ischaemia between CT-FFR and the stress ECHO.

Effect of Calcification Based on Computer-Aided System on CT-Fractional Flow Reserve in Diagnosis of Coronary Artery Lesion

This study was to analyze the diagnostic value of coronary computed tomography angiography (CCTA) and fractional flow reserve (FFR) based on computer-aided diagnosis (CAD) system for coronary lesions and the possible impact of calcification. 80 patients who underwent CCTA and FFR examination in hospital were selected as the subjects. The FFR value of 0.8 was used as the dividing line and divided into the ischemic group (FFR ≤ 0.8) and nonischemic group (FFR > 0.8). The basic data and imaging characteristics of patients were analyzed. The maximum diameter stenosis rate (MDS %), maximum area stenosis rate (MAS %), and napkin ring sign (NRS) in the ischemic group were significantly lower than those in the nonischemic group (P < 0.05). Remodeling index (RI) and eccentric index (EI) compared with the nonischemic group had no significant difference (P > 0.05). The total plaque volume (TPV), total plaque burden (TPB), calcified plaque volume (CPV), lipid plaque volume (LPV), and lipid plaque burden (LPB) in the ischemic group were significantly different from those in the non-ischemic group (P < 0.05). MAS % had the largest area under curve (AUC) for the diagnosis of coronary myocardial ischemia (0.74), followed by MDS % (0.69) and LPV (0.68). CT-FFR had high diagnostic sensitivity, specificity, accuracy, truncation value, and AUC area data for patients in the ischemic group and nonischemic group. The diagnostic sensitivity, specificity, accuracy, cutoff value, and AUC area data of CT-FFR were higher in the ischemic group (89.93%, 92.07%, 95.84%, 60.51%, 0.932) and nonischemic group (93.75%, 90.88%, 96.24%, 58.22%, 0.944), but there were no significant differences between the two groups (P > 0.05). In summary, CT-FFR based on CAD system has high accuracy in evaluating myocardial ischemia caused by coronary artery stenosis, and within a certain range of calcification scores, calcification does not affect the diagnostic accuracy of CT-FFR.

The Value of CTA Based on Gold Nanorod Contrast Agent in Coronary Artery Diagnosis and Plaque Property Analysis

Coronary CT angiography (CTA) with the characteristics of noninvasive and simple operation is widely used in the diagnosis of coronary artery stenosis. The choice of contrast agent exerts an important impact on the imaging quality of CTA. Conventional iodine contrast agents are easily excreted by the kidneys, from which the imaging window is short, and the imaging quality is poor. Metal nanomaterials have unique optical properties and have broad application prospects in imaging. Our aim is to explore the value of gold nanorod contrast agent in the diagnosis of coronary heart disease. A gold nanorod suspension was first prepared, and the prepared gold nanorod was uniform and had good dispersibility. It can be seen from the light absorption curve that there are two obvious peaks on the UV absorption peak of the gold nanorods. The gold nanorods were cultured in different solutions, and it was found that the particle size of the gold nanorods did not change significantly within 72 hours, indicating that the prepared gold nanorods had good stability. When observing the damage degree of mouse kidney tissue, it was shown that the damage degree of gold nanorod contrast agent to mouse kidney tissue was less than that of iodine contrast agent. The above results indicate that the gold nanorod contrast agent has good stability and safety. Therefore, our study demonstrated that the gold nanorod contrast agent has high value in the diagnosis of coronary arteries and the analysis of plaque properties.

Applicability of the Leiden Convention and the Lipton Classification in Patients with a Single Coronary Artery in the Setting of Congenital Heart Disease

In single coronary artery (SCA) anatomy, all coronary tributaries arise from a single ostium, providing perfusion to the entire myocardium. Coronary classification systems can facilitate the description of SCA anatomy. Aim: Evaluation of the applicability of Lipton classification and the Leiden Convention coronary coding system in SCA. Methods: All patients (n = 6209) who underwent computed tomography (CT) scanning between 2014 and 2018 were retrospectively examined for the presence of SCA and classified, according to Lipton classification and the Leiden Convention coronary coding system. Results: The prevalence of SCA was 0.51% (32/6209). Twenty-eight patients (87.5%) had coexisting congenital heart disease (CHD), most frequently pulmonary atresia (9/32, 28.1%). Ten patients (10/32, 31.25%) could not be classified with either the Leiden Convention or Lipton classification (pulmonary atresia n = 9, common arterial trunk (CAT) n = 1). In one case with CAT, Lipton classification, but not the Leiden Convention, could be applied. In two cases with the transposition of the great arteries and in two cases of double outlet right ventricle, the Leiden Convention, but not the Lipton classification, could be applied. Conclusions: Both classifications are useful to detail information about SCA. As Lipton classification was not developed for structural heart disease cases, in complex CHD with abnormal position of the great arteries, the Leiden Convention is better applicable. The use of both systems is limited in pulmonary atresia. In this scenario, it is better to provide a precise description of the coronary origin and associated characteristics that might affect treatment and prognosis.

Coronary Vasculitis

The term coronary “artery vasculitis” is used for a diverse group of diseases with a wide spectrum of manifestations and severity. Clinical manifestations may include pericarditis or myocarditis due to involvement of the coronary microvasculature, stenosis, aneurysm, or spontaneous dissection of large coronaries, or vascular thrombosis. As compared to common atherosclerosis, patients with coronary artery vasculitis are younger and often have a more rapid disease progression. Several clinical entities have been associated with coronary artery vasculitis, including Kawasaki’s disease, Takayasu’s arteritis, polyarteritis nodosa, ANCA-associated vasculitis, giant-cell arteritis, and more recently a Kawasaki-like syndrome associated with SARS-COV-2 infection. This review will provide a short description of these conditions, their diagnosis and therapy for use by the practicing cardiologist.

Comparison on radiation effective dose and image quality of right coronary artery on prospective ECG-gated method between 320 row CT and 2nd generation (128-slice) dual source CT

This retrospective study was to compare the image quality of right coronary artery (RCA) and effective radiation dose on prospective ECG‐gated method between 320 row computed tomography (CT) and 2nd generation (128‐slice) dual source CT. A total of 215 candidates underwent CT coronary angiography using prospective ECG‐gated method, 120 patients enrolled in 320 row CT group, and 95 patients in dual source CT group. We divided RCA image quality scores as 1/2/3/4, which means excellent/good/adequate/not assessable and heart rates were considered, as well as the radiation dose. There is no statistically significant difference of RCA image quality of Score 1/2 between 320 row CT and 2nd generation dual source CT, but lower heart rate (<70/min) improved RCA image quality. Meanwhile, the 2nd generation dual source CT scan have significant lower radiation dose. For patients with high level heart rate variation, both prospective ECG‐gated method of 320 row CT scan (Toshiba) and 2nd generation dual source CT scan (Siemens) basically provided good image quality on RCA. There is an advantage of effective radiation dose reduction in prospective ECG‐gated method using the 2nd generation dual source CT scan. After the iodine contrast agent was injected into elbow vein, the threshold triggering method was used to carry out prospective gated scanning, and the acquired fault image was reconstructed by the standard post‐processing software of each manufacturer. The radiation dose value is obtained through the dose report automatically generated after each scan.