Prevalence and burden of coronary artery disease on computed tomography coronary angiography and its correlation with high-density lipoprotein in the Northern Territory, Australia.

Indigenous Australians are known to have a higher prevalence of coronary artery disease (CAD) than non-Indigenous counterparts. Atherogenic lipid profiles, characterised by low serum levels of high-density lipoprotein (HDL) and higher serum triglycerides, have been shown to be more prevalent in Indigenous Australians. The use of computed tomography coronary angiography (CTCA) for risk stratification and diagnosis of CAD has been validated in moderate risk populations, but limited data exists in specific high-risk populations such as Indigenous Australians. Through a retrospective study of patient records, we aimed to confirm if an atherogenic lipid profile occurred in Indigenous Australians undergoing CTCA in the Northern Territory of Australia and if so, whether this correlated with the prevalence or burden of CAD. We demonstrate that Indigenous Australians have similar prevalence (52.6% vs. 50.3%, P=0.80) and burden of CAD (Leaman score 6.03±4.66 vs. 6.96±4.82, P=0.44) on CTCA as non-Indigenous patients, but were 8 years younger (41.9±8.9 vs. 50.0±11.9 years, P<0.001) at the time of examination. We confirmed the presence of an atherogenic lipid profile in Indigenous patients and showed low serum-HDL was associated with very premature (patients aged 18-35 years) CAD in comparison to premature (patients aged 36-55 years) and mature-onset (patients aged 56 years and older) CAD (0.71±0.25 vs. 1.09±0.35 vs. 1.18±0.36 mmol/L, P=0.009). Future clinical guidelines should consider the role of CTCA in Indigenous Australians and whether younger patients may benefit. The causes of premature CAD, including atherogenic lipid profiles, require an ongoing focus in order to achieve equitable cardiovascular outcomes for Indigenous and non-Indigenous Australians.

Case report: intravascular ultrasound-guided entry to an anomalous highly angulated circumflex coronary artery originating from the right sinus of Valsalva.

Background: Anomalous coronary arteries originating from the contralateral sinus of Valsalva constitute a rare congenital anomaly. Most of such anomalous coronary arteries exhibit slit-like orifice that are often compounded by external compressive factors. Consequently, percutaneous coronary intervention (PCI) of these vessels poses considerable challenges, both in terms of cannulation but also intervention in often acutely angulated vessels. Case summary: A 61-year-old man, with a history of previous coronary artery bypass graft surgery and PCI presented with a history consistent with unstable angina. Notably, the left circumflex artery (LCX) in this individual exhibited an anomalous origin. Due to unfavourable anatomy and ambiguous LCX ostium take-off, previous operators had elected PCI of the saphenous vein graft (SVG) anastomosed to the obtuse marginal branch. A computed tomography scan on this occasion confirmed occlusion of the SVG and defined precise origin of anomalous coronary artery. Real-time live intravascular ultrasound (IVUS) positioned in the ascending aorta, in the right sinus of Valsalva, allowed visualization of the origin and wiring of the anomalous circumflex coronary artery and also facilitated successful PCI. Discussion: As far as we are aware, this is the first description of IVUS assisted wiring of an anomalous coronary artery. Intravascular ultrasound also facilitated decision making in this complex angioplasty of an angulated and heavily diseased circumflex coronary artery.

A Cardiologist's Clinical Dilemma: An Incidental Finding of a Potentially High-Risk Anomalous Right Coronary Artery Origin.

Coronary artery anomalies may place patients at risk for various adverse events. We present a case of a 62-year-old male with a two-year history of intermittent chest pain. A computed tomography coronary angiogram revealed a rare finding of an anomalous right coronary artery (ARCA) originating from the left ascending aorta, with high-risk features. This case highlights the complexities in diagnosing and managing ARCA, underscoring the importance of individualized care and careful consideration of invasive intervention risks versus potential benefits.

Association between vessel-specific coronary Aggregated plaque burden, Agatston score and hemodynamic significance of coronary disease (The CAPTivAte study).

Background: CT coronary angiography (CTCA) is a guideline-endorsed assessment for patients with stable angina and suspected coronary disease. Although associated with excellent negative predictive value in ruling out obstructive coronary disease, there are limitations in the ability of CTCA to predict hemodynamically significant coronary disease. The CAPTivAte study aims to assess the utility of Aggregated Plaque Burden (APB) in predicting ischemia based on Fractional Flow Reserve (FFR). Methods: In this retrospective study, patients who had a CTCA and invasive FFR of the LAD were included. The entire length of the LAD was analyzed using semi-automated software which characterized total plaque burden and plaque morphological subtype (including Low Attenuation Plaque (LAP), Non-calcific plaque (NCP) and Calcific Plaque (CP). Aggregated Plaque Burden (APB) was calculated. Univariate and multivariate analysis were performed to assess the association between these CT-derived parameters and invasive FFR. Results: There were 145 patients included in this study. 84.8 % of patients were referred with stable angina. There was a significant linear association between APB and FFR in both univariate and multivariate analysis (Adjusted R-squared = 0.0469; p = 0.035). Mean Agatston scores are higher in FFR positive vessels compared to FFR negative vessels (371.6 (±443.8) vs 251.9 (±283.5, p = 0.0493). Conclusion: CTCA-derived APB is a reliable predictor of ischemia assessed using invasive FFR and may aid clinicians in rationalizing invasive vs non-invasive management strategies. Vessel-specific Agatston scores are significantly higher in FFR-positive vessels than in FFR-negative vessels. Associations between HU-derived plaque subtype and invasive FFR were inconclusive in this study.

Giant coronary aneurysm in a toddler with Kawasaki disease: technical challenges in CT coronary angiography.

Kawasaki disease is the most common vasculitis causing acquired coronary artery aneurysm (CAA) and affects mostly children. Computed tomography coronary angiography (CTCA) has unique diagnostic and prognostic values in cases of giant CAA. Here, we report technical challenges encountered when performed CTCA for a case of Kawasaki disease complicated with giant CAA. In particular, there was significant flow alteration caused by the giant CAA(s) causing suboptimal enhancement when the standard protocol was applied. We share our experience in optimizing the scan and propose the use of either manual bolus tracking or test bolus technique in similar scenarios, as well as multidisciplinary approach to optimize patient preparation.

CTCA in children with severe heterozygous familial hypercholesterolaemia: Screening for subclinical atherosclerosis.

Familial hypercholesterolemia (FH) is one of the most common genetically inherited disorders in the world. Children with severe heterozygous FH (HeFH), i.e. untreated low-density lipoprotein cholesterol (LDL-C) levels above the 90th percentile for age and sex among FH mutation carriers, can have LDL-C levels that overlap levels of children with homozygous FH (HoFH), but treatment regimen and cardiovascular follow-up to prevent cardiovascular disease are less intensive in children with severe HeFH. In children with HoFH, subclinical atherosclerosis can already be present using computed tomography coronary angiography (CTCA). The question remains whether this is also the case in children with severe HeFH who have a high exposure to elevated LDL-C levels from birth onwards as well. We calculated the cumulative LDL-C exposure (CEtotal [mmol]) in four children with severe HeFH and performed computed tomography coronary angiography (CTCA). These children, aged 13, 14, 15 and 18 years, had CEtotal of 71.3, 97.8, 103.6 and 136.1 mmol, respectively. None of them showed abnormalities on cardiovascular imaging, despite high LDL-C exposure. The results of this study, do not give us an indication to recommend performing CTCA routinely in children with severe HeFH.

Coronary Artery Fistula: A Diagnostic Dilemma.

Coronary artery fistula (CAF), although one of the rare coronary anomalies, is becoming increasingly more detectable in the recent years due to advancements in cardiac diagnostic imaging. Its long-term prognostic implications and importance for the cardiovascular system remain a dilemma for cardiologists and patients. Based on a variety of haemodynamic symptoms and complications, cardiologists must be aware of the characteristics of CAF and the diagnostic importance of multi-slice CT in evaluation, pre-procedural management and follow-up. Both surgical and percutaneous options are available for symptomatic patients or those with complications, while management of asymptomatic CAF remains a viable alternative.

Serum Soluble Lectin-like Oxidized Low-Density Lipoprotein Receptor-1 (sLOX-1) Is Associated with Atherosclerosis Severity in Coronary Artery Disease.

Risk-factor-based scoring systems for atherosclerotic coronary artery disease (CAD) remain concerningly inaccurate at the level of the individual and would benefit from the addition of biomarkers that correlate with atherosclerosis burden directly. We hypothesized that serum soluble lectin-like oxidized low-density lipoprotein receptor-1 (sLOX-1) would be independently associated with CAD and investigated this in the BioHEART study using 968 participants with CT coronary angiograms, which were scored for disease burden in the form of coronary artery calcium scores (CACS), Gensini scores, and a semi-quantitative soft-plaque score (SPS). Serum sLOX-1 was assessed by ELISA and was incorporated into regression models for disease severity and incidence. We demonstrate that sLOX-1 is associated with an improvement in the prediction of CAD severity when scored by Gensini or SPS, but not CACS. sLOX-1 also significantly improved the prediction of the incidence of obstructive CAD, defined as stenosis in any vessel >75%. The predictive value of sLOX-1 was significantly greater in the subgroup of patients who did not have any of the standard modifiable cardiovascular risk factors (SMuRFs). sLOX-1 is associated with CAD severity and is the first biomarker shown to have utility for risk prediction in the SMuRFless population.

Early outcomes following integration of computed tomography (CT) coronary angiography service in an established cardiology practice in disease management.

BACKGROUND: Computed tomography coronary angiography (CTCA) is an established modality for the diagnosis and assessment of cardiovascular disease. However, price and space pressure have mostly necessitated outsourcing CTCA to external radiology providers. Advara HeartCare has recently integrated CT services within local clinical networks across Australia. This study examined the benefits of the presence (integrated) or absence (pre-integrated) of this "in-house" CTCA service in real-world clinical practice. METHODS: De-identified patient data from electronic medical records were used to create an Advara HeartCare CTCA database. Data analysis included clinical history, demographics, CTCA procedure, and 30-day outcomes post-CTCA from two age-matched cohorts: integrated (n â€‹= â€‹495) and pre-integrated (n â€‹= â€‹456). RESULTS: Data capture was more comprehensive and standardised across the integrated cohort. There was a 21% increase in referrals for CTCA from cardiologists observed for the integration cohort vs. pre-integration [n â€‹= â€‹332 (72.8%) pre-integration vs. n â€‹= â€‹465 (93.9%) post-integration, p â€‹< â€‹0.0001] with a parallel increase in diagnostic assessments including blood tests [n â€‹= â€‹209 (45.8%) vs. n â€‹= â€‹387 (78.1%), respectively, p â€‹< â€‹0.0001]. The integrated cohort received lower total dose length product [Median 212 (interquartile range 136-418) mGy∗cm vs. 244 (141.5, 339.3) mGy∗cm, p â€‹= â€‹0.004] during the CTCA procedure. 30-days after CTCA scan, there was a significantly higher use of lipid-lowering therapies in the integrated cohort [n â€‹= â€‹133 (50.5%) vs. n â€‹= â€‹179 (60.6%), p â€‹= â€‹0.04], along with a significant decrease in the number of stress echocardiograms performed [n â€‹= â€‹14 (10.6%) vs. n â€‹= â€‹5 (11.6%), p â€‹= â€‹0.01]. CONCLUSION: Integrated CTCA has salient benefits in patient management, including increased pathology tests, statin usage, and decreased post-CTCA stress echocardiography utilisation. Our ongoing work will examine the effect of integration on cardiovascular outcomes.

An All-in-One Tool for 2D Atherosclerotic Disease Assessment and 3D Coronary Artery Reconstruction.

Diagnosis of coronary artery disease is mainly based on invasive imaging modalities such as X-ray angiography, intravascular ultrasound (IVUS) and optical coherence tomography (OCT). Computed tomography coronary angiography (CTCA) is also used as a non-invasive imaging alternative. In this work, we present a novel and unique tool for 3D coronary artery reconstruction and plaque characterization using the abovementioned imaging modalities or their combination. In particular, image processing and deep learning algorithms were employed and validated for the lumen and adventitia borders and plaque characterization at the IVUS and OCT frames. Strut detection is also achieved from the OCT images. Quantitative analysis of the X-ray angiography enables the 3D reconstruction of the lumen geometry and arterial centerline extraction. The fusion of the generated centerline with the results of the OCT or IVUS analysis enables hybrid coronary artery 3D reconstruction, including the plaques and the stent geometry. CTCA image processing using a 3D level set approach allows the reconstruction of the coronary arterial tree, the calcified and non-calcified plaques as well as the detection of the stent location. The modules of the tool were evaluated for efficiency with over 90% agreement of the 3D models with the manual annotations, while a usability assessment using external evaluators demonstrated high usability resulting in a mean System Usability Scale (SUS) score equal to 0.89, classifying the tool as "excellent".

CT angiography compared to invasive angiography for stable coronary disease as predictors of major adverse cardiovascular events- A systematic review and meta-analysis.

BACKGROUND: Computational tomography coronary angiography (CTCA) is increasingly the diagnostic test of choice for investigating patients with stable anginal symptoms. OBJECTIVES: We sought to conduct a systematic review and meta-analysis comparing CTCA with invasive coronary angiography (ICA) with regards to major adverse cardiovascular events (MACE), procedural complications and rates of revascularisation. METHODS: We conducted a systematic review and meta-analysis in line with the PRISMA statement. A literature search was conducted using PubMed, MEDLINE Ovid and Embase, with three studies included in meta-analysis. Statistical analysis was undertaken using Review Manager 5.3 for MacOS software and outcomes expressed as odds ratio, with 95% confidence intervals and sensitivity analysis was conducted. RESULTS: A total of 5662 patients were included in this study level meta-analysis. There was no difference in MACE between CT and angiography [2.97% v 3.45%, fixed-effect model, OR: 0.84 (0.62-1.14), p = 0.26, I2 0%] and no difference found in rates of myocardial infarction, death or stroke. CTCA was associated with a reduced rate of revascularisation [12.6% v 18.3%, fixed-effects model, OR: 0.64 (0.55-0.75), p<0.00001, I2 =0%]. However, CTCA was not associated with a significantly lower complication rate [0.5% v 1.72%, random effects model, OR: 0.52 (0.06-4.38), p = 0.55, I2 52%]. CONCLUSION: CTCA is a safe strategy for investigating patients with stable angina with no associated increase in MACE but a reduction in revascularisation rates.

Multi-vessel giant coronary artery aneurysms: An unusual cause of chest pain.

We describe an unusual case of multi-vessel giant coronary artery aneurysms complicated by acute coronary syndrome despite escalation of therapy. A 65-year-old man with hypertension and hypercholesterolemia presented to clinic with atypical chest pain over 4 months. Outpatient computed tomography coronary angiography (CTCA) demonstrated giant coronary aneurysms involving all 3 major coronary arteries. Outpatient coronary angiogram findings were in concordance with the CTCA with no definite obstructive coronary disease. Myocardial perfusion imaging was normal. He was commenced on dual antiplatelet therapy (DAPT). At 6 months, he presented with chest pain and non-ST-elevation myocardial infarction. Repeat coronary angiogram demonstrated occluded first septal LAD branch which previously had aneurysmal dilatation. DAPT was changed to long-term oral anticoagulation. He remains well at 18 months. This case highlights the importance of multi-modality imaging in the diagnosis and workup of coronary artery aneurysms and challenges in management; an individualized approach is required.

From Coronary Artery Ectasia to Giant Coronary Artery Aneurysm: Is it Necessary to Follow-Up?

Here we present a case of an asymptomatic patient with a giant coronary artery aneurysm developed in the context of diffuse coronary artery ectasia. Giant coronary artery aneurysm was complicated by the presence of a large thrombus. The heart team settled for surgical treatment of the lesion. (Level of Difficulty: Intermediate.).

A rare case of isolated single coronary artery, Lipton's type LIIB diagnosed by computed tomography coronary angiography.

Single coronary artery (SCA) is a very rare coronary artery anomaly of origin and course with a reported prevalence of only 0.024%-0.066% among patients undergoing routine coronary angiography. The majority of the individuals remain asymptomatic and thus SCA is found only incidentally on conventional or computed tomography coronary angiography done for other reasons. A minority of the patients may have non-specific cardiac symptoms (such as ischemic pain, tachycardia, etc.) or even sudden death. SCA can occur in isolation or in association with other congenital cardiac defects like such as persistent truncus arteriosus, tetralogy of Fallot (TOF), pulmonary atresia, transposition of great vessels (TGA), ventricular septal defect (VSD), coronary arteriovenous fistula (AVF), patent foramen ovale (PFO) and bicuspid aortic valve. We present a case of 50 years male with incidental finding of SCA arising from the left coronary sinus which had an inter-arterial course before branching (SCA Type: LIIB based on the Lipton-Yamanaka classification) which was revealed on computed tomography coronary angiography (CTCA) performed after the patient complained of infrequent chest pain. Management of the diagnosed cases can be either conservative, stent placement or surgical correction based on the symptomatology and clinico-lab findings.

Quantitative plaque characterisation and association with acute coronary syndrome on medium to long term follow up: insights from computed tomography coronary angiography.

Background: Computed tomography coronary angiography (CTCA) is an established imaging modality widely used for diagnosing coronary artery stenosis with expanding potential for comprehensive assessment of coronary artery disease (CAD). Lesion-based analyses of high-risk plaques (HRP) on CTCA may aid further in prognostication presenting with stable chest pain. We conduct qualitative and quantitative assessments to identify HRPs that are associated with acute coronary syndrome (ACS) on a medium to long term follow-up. Methods: Retrospective cohort study of patients who underwent CTCA for suspected CAD. Obstructive stenosis (OS) is defined as ≥50% and the presence of HRP and its constituents: positive-remodelling (PR), low-attenuation-plaque (LAP; <56 HU), very-low-attenuation-plaque (vLAP; <30 HU) and spotty-calcification (SC) were recorded. A cross-sectional quantitative analysis of HRP was performed at the site of minimum-luminal-area (MLA). The primary endpoint was fatal or non-fatal ACS on follow-up. Results: A total of 1,257 patients were included (mean age 61±14 years old and 51% male) with a median follow-up of 7.24 years (interquartile range 5.5 to 7.7 years). The occurrence of ACS was significantly higher in HRP (+) patients compared to HRP (-) patients and patients with no plaques (20.5% vs. 1.6% vs. 0.4%, log-rank test P<0.001). ACS was more frequent in HRP (+)/OS (+) patients (20.7%) compared to HRP (+)/OS (-) patients (8.6%), HRP (-)/OS (+) patients (1.8%) and HRP (-)/OS (-) patients (1.0%). OS, cross-sectional plaque area (PA) and the presence of vLAP identified those HRP lesions that were more likely to cause future ACS. Cross-sectional LAP area (<56 HU) in HRP lesions added incremental prognostic value to OS in predicting ACS (P=0.008). Conclusions: The presence of OS and the LAP area at the site of MLA identify the HRP lesions that have the greatest association with development of future ACS.

Multiple myocardial bridging in the elderly: A rare case.

Myocardial bridging occurs when a segment of major epicardial coronary artery courses intramurally through myocardium, commonly involving the left anterior descending. However, myocardial bridging involving coronary arteries other than left anterior descending is less-common and rarely reported, especially in the elderly population. We report a rare case of multiple myocardial bridging involving the left anterior descending, first obtuse marginal, and ramus intermedius in a 68-year-old Asian female. We also briefly discuss the imaging evaluation and pathophysiology of myocardial ischemia in myocardial bridging. This is the second reported case of myocardial bridging involving such combination, and to our knowledge, the first for elderly patient.