Noninvasive cardiac imaging with computed tomography

Critical Insights Into the Management of Postpartum Left Main Spontaneous Coronary Artery Dissection: Current Strategies and Future Directions

This review article delves into the multifaceted realm of postpartum left main spontaneous coronary artery dissection (PLMSCAD), an infrequent yet critical condition affecting women during the postpartum period. Through a comprehensive exploration of its pathophysiology, clinical presentation, diagnosis, management strategies, and future directions, this review provides a holistic understanding of PLMSCAD's complexities. The article highlights challenges in diagnosis due to overlapping symptoms and underscores the significance of prompt recognition and tailored interventions. Current management strategies, encompassing medical and interventional approaches, are analysed in the context of their short-term and long-term impact on patient outcomes. Ethical considerations and the role of patient education and support networks are explored, shedding light on the broader psychosocial dimensions of PLMSCAD management. As emerging research reveals insights into genetic influences, hormonal dynamics, and the prognosis of affected individuals, this review emphasises the necessity of collaborative research endeavours and data sharing to enhance our understanding and guide future strategies. Ultimately, this review underscores the urgency of addressing the unique needs of women experiencing PLMSCAD, urging ongoing research, multidisciplinary collaboration, and a patient-centred approach to optimise maternal health outcomes and well-being.

Deep Learning for COVID-19 Diagnosis from CT Images

COVID-19, an infectious coronavirus disease, caused a pandemic with countless deaths. From the outset, clinical institutes have explored computed tomography as an effective and complementary screening tool alongside the reverse transcriptase-polymerase chain reaction. Deep learning techniques have shown promising results in similar medical tasks and, hence, may provide solutions to COVID-19 based on medical images of patients. We aim to contribute to the research in this field by: (i) Comparing different architectures on a public and extended reference dataset to find the most suitable; (ii) Proposing a patient-oriented investigation of the best performing networks; and (iii) Evaluating their robustness in a real-world scenario, represented by cross-dataset experiments. We exploited ten well-known convolutional neural networks on two public datasets. The results show that, on the reference dataset, the most suitable architecture is VGG19, which (i) Achieved 98.87% accuracy in the network comparison; (ii) Obtained 95.91% accuracy on the patient status classification, even though it misclassifies some patients that other networks classify correctly; and (iii) The cross-dataset experiments exhibit the limitations of deep learning approaches in a real-world scenario with 70.15% accuracy, which need further investigation to improve the robustness. Thus, VGG19 architecture showed promising performance in the classification of COVID-19 cases. Nonetheless, this architecture enables extensive improvements based on its modification, or even with preprocessing step in addition to it. Finally, the cross-dataset experiments exposed the critical weakness of classifying images from heterogeneous data sources, compatible with a real-world scenario.

3D reconstruction of coronary artery bifurcations from coronary angiography and optical coherence tomography: feasibility, validation, and reproducibility

The three-dimensional (3D) representation of the bifurcation anatomy and disease burden is essential for better understanding of the anatomical complexity of bifurcation disease and planning of stenting strategies. We propose a novel methodology for 3D reconstruction of coronary artery bifurcations based on the integration of angiography, which provides the backbone of the bifurcation, with optical coherence tomography (OCT), which provides the vessel shape. Our methodology introduces several technical novelties to tackle the OCT frame misalignment, correct positioning of the OCT frames at the carina, lumen surface reconstruction, and merging of bifurcation lumens. The accuracy and reproducibility of the methodology were tested in n = 5 patient-specific silicone bifurcations compared to contrast-enhanced micro-computed tomography (µCT), which was used as reference. The feasibility and time-efficiency of the method were explored in n = 7 diseased patient bifurcations of varying anatomical complexity. The OCT-based reconstructed bifurcation models were found to have remarkably high agreement compared to the µCT reference models, yielding r² values between 0.91 and 0.98 for the normalized lumen areas, and mean differences of 0.005 for lumen shape and 0.004 degrees for bifurcation angles. Likewise, the reproducibility of our methodology was remarkably high. Our methodology successfully reconstructed all the patient bifurcations yielding favorable processing times (average lumen reconstruction time < 60 min). Overall, our method is an easily applicable, time-efficient, and user-friendly tool that allows accurate and reproducible 3D reconstruction of coronary bifurcations. Our technique can be used in the clinical setting to provide information about the bifurcation anatomy and plaque burden, thereby enabling planning, education, and decision making on bifurcation stenting.

Coronary Artery Anomalies in Tetralogy of Fallot Patients Undergoing CT Angiography at a Tertiary Care Hospital

Background

The aim of this study was to determine the frequency of coronary artery anomalies (CAAs) in Tetralogy of Fallot (TOF) patients undergoing computed tomography (CT)-angiography in a tertiary care hospital.

Methodology

In this observational study, we included consecutive TOF patients undergoing CT-angiography without prior history of cardiac surgery or congenital heart disease. CAAs were defined based on either origin or course of the artery.

Results

Out of 441 TOF patients, the prevalence of CCAs was 3.6% (16), of which 13 were below 18 years of age. Anomalous left main artery was observed in six (1.4%) patients, followed by left anterior descending artery and right coronary artery, observed in four (0.9%) patients each, and two (0.5%) patients had a single coronary artery originating from the left coronary cusp with an interarterial course.

Conclusions

CAAs were observed in a significant number (3.6%) of TOF patients. A CT-angiographic assessment before surgical correction would help identify the exact anatomy for better surgical planning to minimize complications.

Can coronary artery anomalies be detected on CT calcium scoring studies?

PURPOSE

To determine whether coronary artery anomalies can be detected on noncontrast computed tomography (CT) coronary artery calcium scoring (CCS) studies.

MATERIALS AND METHODS

A total of 126 patients (mean age 62 years; 35 women) underwent noncontrast CCS and contrast enhanced coronary CT angiography (cCTA). Thirty-three patients were diagnosed with a coronary anomaly on cCTA, whereas coronary anomalies were excluded in 93. Two observers (reader 1 [R1] and reader 2 [R2]), blinded to patient information independently evaluated each CCS study for: 1) visibility of coronary artery origins, 2) detection of coronary anomalies, and 3) benign or malignant (ie, interarterial) course. Using cCTA as the reference standard, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of CCS studies for detecting coronary anomalies were calculated.

RESULTS

Of the 33 coronary anomalies, 16 were benign and 17 malignant. Based on noncontrast CCS studies, R1 and R2 correctly identified the left main origin in 123/126 (97.6%) and 121/126 (96%) patients; the left anterior descending origin in 125/126 (99.2%) and 122/126 (96.8%); the circumflex origin in 120/126 (95.2%) and 105/126 (83.3%); and the right coronary artery origin in 117/126 (92.9%) and 103/126 (81.7%), respectively. R1 and R2 identified 34 and 27 coronary anomalies and classified 19 and 15 as malignant, respectively. Interobserver reproducibility for detection of coronary anomalies was good (k = 0.76). Interobserver agreement for detection of malignant variants was even stronger (k = 0.80). On average, coronary artery anomalies were diagnosed with 85.2% sensitivity, 96.4% specificity, 90.5% PPV, and 94.1% NPV on noncontrast CCS studies.

CONCLUSION

Benign and malignant coronary artery anomalies can be detected with relatively high accuracy on noncontrast-enhanced CCS studies. CCS studies should be reviewed for signs of coronary artery anomalies in order to identify malignant variants with possible impact on patient management.

Coronary to pulmonary artery fistula: morphologic features at multidetector CT

The objective of this study is to evaluate the incidence and morphologic features of coronary-pulmonary artery fistulas (CPAF) by multidetector computed tomography (MDCT). From 2006 to 2008, 5,372 patients underwent ECG-gated cardiac CT scans using 64-slice MDCT at our institute. Among them, 17 cases of CPAF were detected (M:F = 14:3, mean age = 63 years). Chief complaints of patients were chest pain (n = 12), abnormal cardiac test (n = 3), known coronary artery disease (n = 1), and known CPAF (n = 1). We retrospectively analyzed the morphologic features of CPAF, such as origin vessels, draining site, fistula size, and aneurysmal sac. Five cases underwent coronary angiography (CAG) and correlated with MDCT findings. Incidence of CPAF was 0.32% by MDCT. The origin of CPAF was the left coronary artery in five (29.4%), the right coronary artery in two (11.8%) and both coronary arteries in ten cases (58.8%). In regard to the diameter of the detected fistula, the diameter of the largest vessel excluding aneurysm was variable from less than 2 to 5.7 mm. Five patients (29.4%) had a fistula that was shown as one vessel that could be traced, one patient (5.9%) was shown as two vessels, and eleven patients (64.7%) were shown as innumerable multiple vessel networks. Five cases were associated with aneurysm (29.4%). Fistulas were located primarily in the left anterolateral aspect of the pulmonary trunk (82.3%) and mostly the drainage site was the left lateral side of the pulmonary trunk (82.3%). CAG was performed in five cases and revealed identical findings to MDCT. In conclusion, coronary-pulmonary artery fistula is more frequently found than anticipated on MDCT. CPAF is supplied by either single or both coronary arteries and drains to the left side of the pulmonary trunk. It is typically located in the anterolateral aspect of the pulmonary trunk. Sometimes CPAF is associated with aneurysms.

Controlling rate and rhythm increases feasibility of CT angiography in atrial fibrillation

A woman, aged 48 years, with severe rheumatic mitral stenosis and uncontrolled permanent atrial fibrillation (AF) underwent preoperative assessment of coronary arteries. Invasive coronary angiography was not possible because of occluded common iliac artery and bilateral radial spasm. Transesophageal echocardiogram showed a very large mobile left atrial appendage clot, precluding cardioversion. The severe motion artifacts during cardiac CT angiography (64 slices) due to atrial fibrillation were overcome by controlling rhythm and rate through insertion of a temporary pacemaker via right femoral vein, and slowing heart rate below 65 beats per minute by intravenous metoprolol (25 mg) and verapamil (5 mg). Clear pictures of all coronary arteries as well as the left atrial appendage clot were obtained. The temporary pacemaker was removed after eight hours. Uneventful mechanical mitral valve replacement and maze procedure were performed and the patient was discharged in a stable condition.

Evaluation of coronary artery disease by computed tomography angiography in patients treated for childhood Hodgkin's lymphoma

PURPOSE To detect pathologies in coronary arteries by computed tomography angiography (CTA) in survivors of childhood Hodgkin's lymphoma who have been treated with radiotherapy and/or cardiotoxic agents. PATIENTS AND METHODS Patients with HL who have been in remission for at least 2 years after completion of therapy were included. CBC, lipid profile, urine analysis, brain natriuretic peptide, troponin-T, creatinine kinase-myocardial band, ECG, telecardiography, echocardiography, and CTA of the patients were performed. Cardiac vascular abnormalities were noted. Results A total of 119 patients were included in the study. In 19 patients (16%), we found coronary artery abnormalities. There was a significant difference between the patients who received mediastinal radiotherapy and those who did not (P = .02). By multivariate analysis, in patients receiving mediastinal radiotherapy the risk of developing a coronary artery abnormality was found to increase 6.8 times compared with patients who did not receive mediastinal radiotherapy (P = .009). Stent implantation was performed in a 28-year-old patient because of critical stenosis in right coronary. In two patients some irregularities were detected both in CTA and conventional angiography, and they remained in close follow-up. A 22-year-old patient whose CTA showed critical stenosis in his left anterior descending artery refused the conventional angiography. CONCLUSION To our knowledge, this is the first large study using CTA for detection of coronary abnormalities in patients treated for HL in pediatric age group. Coronary CTA is a minimally invasive tool for early diagnosis of coronary artery disease in patients who were treated with mediastinal radiotherapy and/or cardiotoxic chemotherapy.

Detection of left ventricular thrombus by coronary computed tomography angiography

Left ventricular thrombus is a recognized complication of acute myocardial infarction. The following case report presents a rare case of left ventricular thrombus detection originally via coronary computed tomography angiography, followed by a brief review of imaging modalities that have been used for the detection of left ventricular thrombus in the past.

An initial case of suppressed restenosis with nuclear factor-kappa B decoy transfection after percutaneous coronary intervention

BACKGROUND

Nuclear factor-kappa B (NF-kappaB) is well known for playing a pivotal role in restenosis after percutaneous coronary intervention (PCI).

METHODS AND RESULTS

This is the first report to demonstrate an effect of NF-kappaB decoy oligodeoxynucleotides (ODN) to prevent restenosis after PCI after a 4-year observation using a coronary computed tomography (CT) scan. We showed that the decoy treatment suppressed neointimal formation after stent implantation compared to that in the same artery.

CONCLUSION

Thus, for the first time, we demonstrate the clinical usefulness of the CT scan to reveal the effects of NF-kappaB decoy ODN transfer after PCI.

Plasma levels of HDL subpopulations and remnant lipoproteins predict the extent of angiographically-defined coronary artery disease in postmenopausal women

OBJECTIVE

The association of coronary heart disease (CHD) with subpopulations of triglyceride (TG)-rich lipoproteins and high-density lipoproteins (HDL) is established in men, but has not been well characterized in women.

METHODS AND RESULTS

Plasma HDL subpopulation concentrations, quantified by 2-dimensional gel electrophoresis, and plasma remnant-like particle cholesterol (RLP-C) concentrations were measured in 256 postmenopausal women with established CHD and in 126 CHD-free postmenopausal women. Coronary artery disease was assessed in women with CHD by quantitative coronary angiography. Plasma RLP-C and prebeta1 HDL concentrations were higher and alpha1 and alpha2 HDL concentrations were lower in CHD than in CHD-free women. After adjustment for conventional CHD-risk factors, plasma levels of RLP-C were positively associated with the degree of coronary artery disease. In similar analyses, plasma prebeta1 HDL particle concentrations were positively associated and alpha2 HDL particle concentrations were inversely associated with the extent of coronary atherosclerosis. Plasma TG, low density lipoprotein cholesterol, and HDL cholesterol levels were not associated with the degree of coronary atherosclerosis.

CONCLUSIONS

The degree of coronary atherosclerosis in postmenopausal women is linked to a dysregulation of the TG/HDL metabolism. Subpopulations of TG-rich and HDL lipoproteins are better predictors of disease than TG and HDL cholesterol concentrations.