A Simple Method for Automatic 3D Reconstruction of Coronary Arteries From X-Ray Angiography

Automatic three-dimensional (3-D) reconstruction of the coronary arteries (CA) from medical imaging modalities is still a challenging task. In this study, we present a deep learning-based method of automatic identification of the two ends of the vessel from X-ray coronary angiography (XCA). We also present a method of using template models of CA in matching the two-dimensional segmented vessels from two different angles of XCA. For the deep learning network, we used a U-net consisting of an encoder (Resnet) and a decoder. The two ends of the vessel were manually labeled to generate training images. The network was trained with 2,342, 1,907, and 1,523 labeled images for the left anterior descending (LAD), left circumflex (LCX), and right coronary artery (RCA), respectively. For template models of CA, ten reconstructed 3-D models were averaged for each artery. The accuracy of correspondence using template models was compared with that of manual matching. The deep learning network pointed the proximal region (20% of the total length) in 97.7, 97.5, and 96.4% of 315, 201, and 167 test images for LAD, LCX, and RCA, respectively. The success rates in pointing the distal region were 94.9, 89.8, and 94.6%, respectively. The average distances between the projected points from the reconstructed 3-D model to the detector and the points on the segmented vessels were not statistically different between the template and manual matchings. The computed FFR was not significantly different between the two matchings either. Deep learning methodology is feasible in identifying the two ends of the vessel in XCA, and the accuracy of using template models is comparable to that of manual correspondence in matching the segmented vessels from two angles.

Deep Recursive Bayesian Tracking for Fully Automatic Centerline Extraction of Coronary Arteries in CT Images

Extraction of coronary arteries in coronary computed tomography (CT) angiography is a prerequisite for the quantification of coronary lesions. In this study, we propose a tracking method combining a deep convolutional neural network (DNN) and particle filtering method to identify the trajectories from the coronary ostium to each distal end from 3D CT images. The particle filter, as a non-linear approximator, is an appropriate tracking framework for such thin and elongated structures; however, the robust 'vesselness' measurement is essential for extracting coronary centerlines. Importantly, we employed the DNN to robustly measure the vesselness using patch images, and we integrated softmax values to the likelihood function in our particle filtering framework. Tangent patches represent cross-sections of coronary arteries of circular shapes. Thus, 2D tangent patches are assumed to include enough features of coronary arteries, and the use of 2D patches significantly reduces computational complexity. Because coronary vasculature has multiple bifurcations, we also modeled a method to detect branching sites by clustering the particle locations. The proposed method is compared with three commercial workstations and two conventional methods from the academic literature.

Substantially Elevated Atherosclerotic Risks in Japanese Severe Familial Hypercholesterolemia Defined by the International Atherosclerosis Society

BACKGROUND

The International Atherosclerosis Society (IAS) has proposed "severe familial hypercholesterolemia" (FH) as a phenotype with the highest cardiovascular risk. However, whether this criteria could appropriately stratify a high-risk Japanese patient with FH remains unknown.

OBJECTIVES

This study sought to characterize atherosclerotic cardiovascular diseases in IAS-defined Japanese subjects with severe FH.

METHODS

This study analyzed 380 clinically diagnosed subjects with heterozygous FH without any history of atherosclerotic cardiovascular diseases. Severe FH was defined as untreated low-density lipoprotein cholesterol >400 mg/dL, >310 mg/dL plus 1 high-risk feature, or >190 mg/dL plus 2 high-risk features according to IAS-proposed statement. The occurrence of first and subsequent composite outcomes (cardiac [cardiac death + coronary artery disease + coronary revascularization] and noncardiac events [stroke + peripheral artery disease] was compared between subjects with severe (n = 135) and non-severe (n = 227) FH.

RESULTS

Severe FH was identified in 40.3% of study population. They had higher low-density lipoprotein cholesterol (P < 0.001) and lipoprotein(a) (P = 0.03) levels. Moreover, they more frequently received high-intensity statin (P < 0.001), PCSK9 inhibitor (P < 0.001), and lipoprotein apheresis (P = 0.01) than nonsevere FH subjects did, which resulted in a lower on-treatment low-density lipoprotein cholesterol level of subjects with severe FH (113 ± 47.2 vs 130 ± 53.9 mg/dL; P = 0.007). However, during the 7.4-year observational period, subjects with severe FH exhibited a 9.3-, 15.4-, and 5.9-fold greater risk for first composite (P < 0.001), cardiac (P < 0.001), and noncardiac outcomes (P = 0.02), respectively. Multivariate Cox proportional hazard model consistently revealed the 7.8- and 7.9-fold elevated risks of first (P < 0.001) and of subsequent (P < 0.001) composite outcomes in subjects with severe FH.

CONCLUSIONS

Japanese subjects with severe FH present profound risks of both first and subsequent atherosclerotic cardiovascular diseases in the primary prevention settings. These findings support the clinical applicability of IAS-defined severe FH in Japanese patients, which identifies those who require further stringent antiatherosclerotic management.

Features of Patients Receiving Extracorporeal Membrane Oxygenation Relative to Cardiogenic Shock Onset: A Single-Centre Experience

Background and Objectives: Extracorporeal membrane oxygenation (ECMO) can be helpful in patients with cardiogenic shock associated with myocardial infarction, and its early use can improve the patient survival rate. In this study, we report a mortality rate-difference analysis that examined the time and location of shock occurrence. Materials and Methods: We enrolled patients who underwent ECMO due to cardiogenic shock related to myocardial infarction and assigned them to either a pre- or post-admission shock group. The primary outcome was the 1-month mortality rate; a subgroup analysis was conducted to assess the effect of bailout ECMO. Results: Of the 113 patients enrolled, 67 (38 with pre-admission shock, 29 with post-admission shock) were analysed. Asystole was more frequently detected in the pre-admission shock group than in the post-admission group. In both groups, the commonest culprit lesion location was in the left anterior descending artery. Cardiopulmonary resuscitation was performed significantly more frequently and earlier in the pre-admission group. The 1-month mortality rate was significantly lower in the pre-admission group than in the post-admission group. Male sex and ECMO duration (≥6 days) were factors significantly related to the reduced mortality rate in the pre-admission group. In the subgroup analysis, the mortality rate was lower in patients receiving bailout ECMO than in those not receiving it; the difference was not statistically significant. Conclusions: ECMO application resulted in lower short-term mortality rate among patients with out-of-hospital cardiogenic shock onset than with in-hospital shock onset; early cardiopulmonary resuscitation and ECMO might be helpful in select patients.

The Use of Maximum Entropy to Enhance Wave Intensity Analysis: An Application to Coronary Arteries in Hypertrophic Obstructive Cardiomyopathy

Background: Wave intensity analysis is useful for analyzing coronary hemodynamics. Much of its clinical application involves the identification of waves indicated by peaks in the wave intensity and relating their presence or absence to different cardiovascular events. However, the analysis of wave intensity peaks can be problematic because of the associated noise in the measurements. This study shows how wave intensity analysis can be enhanced by using a Maximum Entropy Method (MEM). Methods: We introduce a MEM to differentiate between "peaks" and "background" in wave intensity waveforms. We apply the method to the wave intensity waveforms measured in the left anterior descending coronary artery from 10 Hypertrophic Obstructive Cardiomyopathy (HOCM) and 11 Controls with normal cardiac function. We propose a naming convention for the significant waves and compare them across the cohorts. Results: Using a MEM enhances wave intensity analysis by identifying twice as many significant waves as previous studies. The results are robust when MEM is applied to the log transformed wave intensity data and when all of the measured data are used. Comparing waves across cohorts, we suggest that the absence of a forward expansion wave in HOCM can be taken as an indication of HOCM. Our results also indicate that the backward compression waves in HOCM are significantly larger than in Controls; unlike the forward compression waves where the wave energy in Controls is significantly higher than in HOCM. Comparing the smaller secondary waves revealed by MEM, we find some waves that are present in the majority of Controls and absent in almost all HOCM, and other waves that are present in some HOCM patients but entirely absent in Controls. This suggests some diagnostic utility in the clinical measurement of these waves, which can be a positive sign of HOCM or a subgroup with a particular pathology. Conclusion: The MEM enhances wave intensity analysis by identifying many more significant waves. The method is novel and can be applied to wave intensity analysis in all arteries. As an example, we show how it can be useful in the clinical study of hemodynamics in the coronary arteries in HOCM.

The Coronary Arteries in Adults after the Arterial Switch Operation: A Systematic Review

Coronary artery status in adults long after the arterial switch operation (ASO) is unclear. We conducted a systematic review to provide an overview of coronary complications during adulthood and to evaluate the value of routine coronary imaging in adults after ASO, in light of current guidelines. Articles were screened for the inclusion of adult ASO patients and data on coronary complications and findings of coronary imaging were collected. A total of 993 adults were followed with a median available follow-up of only 2.0 years after reaching adulthood. Myocardial ischemia was suspected in 17/192 patients (8.9%). The number of coronary interventions was four (0.4%), and coronary death was reported in four (0.4%) patients. A lack of ischemia-related symptoms cannot be excluded because innervation studies indicated deficient cardiac innervation after ASO, although data is limited. Anatomical high-risk features found by routine coronary computed tomography (cCT) included stenosis (4%), acute angle (40%), kinking (24%) and inter-arterial course (11%). No coronary complications were reported during pregnancy (n = 45), although, remarkably, four (9%) patients developed heart failure. The 2020 European Society of Cardiology (ESC) guidelines state that routine screening for coronary pathologies is questionable. Based on current findings and in line with the 2018 American ACC/AHA guidelines a baseline assessment of the coronary arteries in all ASO adults seems justifiable. Thereafter, an individualized coronary follow-up strategy is advisable at least until significant duration of follow-up is available.

Immunomodulation of IL-33 and IL-37 with Vitamin D in the Neointima of Coronary Artery: A Comparative Study between Balloon Angioplasty and Stent in Hyperlipidemic Microswine

Inflammation is a major contributor to the development and progression of atherosclerosis. Interleukin (IL)-33 and IL-37, members of the IL-1 family, modulate inflammation, with IL-33 having a pro-inflammatory effect and IL-37 having anti-inflammatory properties. IL-37 is constitutively expressed at low levels but upregulated in inflammatory contexts. The aim of this study was to evaluate the effect of vitamin D on the expression of IL-33, IL-37, macrophages, and caspase-1 in the neointimal tissue of coronary artery in Yucatan microswine with vitamin D deficient, sufficient, and supplemented status. The intimal injury was induced by balloon angioplasty and stenting in the coronary artery, and tissues were harvested after 6 months. The expression of various proteins of interest was evaluated by immunostaining. Increased expression of IL-33 and IL-37 in the neointimal tissue of the vitamin D deficient, as compared to the sufficient and supplemented microswine, as revealed by histological evaluation and semi-quantitative analysis, suggested the immunomodulatory effect of vitamin D on the expression of IL-33 and IL-37. The minimal expression or absence of IL-33 and IL-37 expression in stented arteries is suggestive of an attenuated inflammatory response in stented arteries, compared to balloon angioplasty. The decreased IL-33 expression in the sufficient and supplemented microswine could be a potential mechanism for controlling the inflammatory process and neointima formation leading to attenuated luminal narrowing of the coronary artery. Overall, these results support supplementation of vitamin D to attenuate inflammation, neointima formation, and restenosis.

IVUS plus multivariate analysis for evaluating the stability of coronary artery plaque in coronary heart disease

OBJECTIVE

To investigate the effect of intravascular ultrasound (IVUS) plus multivariate analysis in evaluating the stability of coronary artery plaque in coronary heart disease (CHD).

METHODS

A retrospective analysis was conducted on ninety-five patients with CHD admitted to our hospital from February 2020 to February 2021. Patients with CHD were examined by IVUS and assigned to a stable plaque group (n=60) and an unstable plaque group (n=35) according to their characteristics. Multivariate logistic regression analysis was performed to evaluate the risk factors affecting the stability of coronary artery plaque.

RESULTS

Of 95 patients, 35 cases with unstable plaque were determined by IVUS, with a detection rate of 36.84%; notable differences were found in HDL-C, hs-CRP, and homocysteine (Hcy) between the two groups (P<0.05). The eccentricity index and reconstruction index of the two groups were statistically different (P<0.05). Moreover, 17 cases were diagnosed by IVUS as mild coronary stenosis, 28 cases as moderate stenosis, and 50 cases as severe stenosis. In addition, compared with the stable plaque group, the unstable plaque group yielded a much higher stenosis rate (P<0.05) and a higher level of plaque thickness and plaque area (P<0.05). Multivariate logistic regression analysis showed eccentricity index, remodeling index, plaque thickness, and plaque area, stenosis rate, HDL-C, Hcy, and hs-CRP were independent risk factors for unstable plaque (P<0.05).

CONCLUSION

IVUS plus multivariate analysis can accurately assess plaque stability.

In Vivo Based Fluid-Structure Interaction Biomechanics of the Left Anterior Descending Coronary Artery

A fluid-structure interaction-based biomechanical model of the entire left anterior descending coronary artery is developed from in vivo imaging via the finite element method in this paper. Included in this investigation is ventricle contraction, three-dimensional motion, all angiographically visible side branches, hyper/viscoelastic artery layers, non-Newtonian and pulsatile blood flow, and the out-of-phase nature of blood velocity and pressure. The fluid-structure interaction model is based on in vivo angiography of an elite athlete's entire left anterior descending coronary artery where the influence of including all alternating side branches and the dynamical contraction of the ventricle is investigated for the first time. Results show the omission of side branches result in a 350% increase in peak wall shear stress and a 54% decrease in von Mises stress. Peak von Mises stress is underestimated by up to 80% when excluding ventricle contraction and further alterations in oscillatory shear indices are seen, which provide an indication of flow reversal and has been linked to atherosclerosis localization. Animations of key results are also provided within a video abstract. We anticipate that this model and results can be used as a basis for our understanding of the interaction between coronary and myocardium biomechanics. It is hoped that further investigations could include the passive and active components of the myocardium to further replicate in vivo mechanics and lead to an understanding of the influence of cardiac abnormalities, such as arrythmia, on coronary biomechanical responses.

Alteration of the soluble guanylate cyclase system in coronary arteries of high cholesterol diet-fed rabbits

This study aimed to investigate how atherosclerosis affects the soluble guanylate cyclase (sGC) system in coronary arteries. Rabbits were fed a normal diet for 12 weeks (N group) or a diet containing high cholesterol (1%) for 4 weeks (S-HC group) and 12 weeks (L-HC group). Cholesterol deposition in the intima of coronary arteries was observed in the S-HC group, but the formation of an atherosclerotic plaque was not observed. In contrast, a major plaque developed in the L-HC group. The relaxant response of isolated coronary arteries to sodium nitroprusside (SNP, nitric oxide donor) was not different between the N and S-HC groups, whereas the response in the L-HC group was markedly attenuated. The relaxation induced by BAY 60-2770 (sGC activator) tended to be augmented in the S-HC group, but it was significantly impaired in the L-HC group compared to that in the N group. sGC β1 immunostaining was equally detected in the medial layer of the arteries among the N, S-HC, and L-HC groups. In addition, a strong staining was observed in the plaque region of the L-HC group. cGMP levels in the arteries stimulated with SNP were identical in the N and S-HC groups and slightly lower in the L-HC group than the other groups. BAY 60-2770-stimulated cGMP formation tended to be increased in the S-HC and L-HC groups. These findings suggest that the sGC system was not normal in atherosclerotic coronary arteries. The redox state of sGC and the distribution pattern are likely to change with the progression of atherosclerosis.

Differential Evaluating Effect on Exercise Capacity of Cardiopulmonary Exercise Testing and Treadmill Exercise Testing in Post-percutaneous Coronary Intervention Patients

Background: Treadmill exercise testing (TET) is commonly used to measure exercise capacity. Studies have shown that cardiopulmonary exercise testing (CPET) is more accurate than TET and is, therefore, regarded as the "gold standard" for testing maximum exercise capacity and prescribing exercise plans. To date, no studies have reported the differences in exercise capacity after percutaneous coronary intervention (PCI) using the two methods or how to more accurately measure exercise capacity based on the results of TET. Aims: This study aims to measure maximum exercise capacity in post-PCI patients and to recommend exercise intensities that ensure safe levels of exercise. Methods: We enrolled 41 post-PCI patients who were admitted to the Cardiac Rehabilitation Clinic at the First Medical Center, the Chinese PLA General Hospital, from July 2015 to June 2016. They completed CPET and TET. The paired sample t-test was used to compare differences in measured exercise capacity, and multiple linear regression was applied to analyze the factors that affected the difference. Results: The mean maximum exercise capacity measured by TET was 8.89 ± 1.53 metabolic equivalents (METs), and that measured by CPET was 5.19 ± 1.23 METs. The difference between them was statistically significant (p = 0.000) according to the paired sample t-test. The difference averaged 40.15% ± 2.61% of the exercise capacity measured by TET multiple linear regression analysis showed that the difference negatively correlated with waist-hip ratio (WHR). Conclusion: For the purpose of formulating more accurate exercise prescription, the results of TET should be appropriately adjusted when applied to exercise capacity assessment. Clinical Trial Registration:http://www.chictr.org.cn/ number, ChiCTR2000031543.

Coronary artery air embolism complicating a CT-guided percutaneous lung biopsy

Coronary arterial air embolism is an extremely rare but readily recognizable condition on computed tomography (CT) that may complicate a lung biopsy. We present an incidence of symptomatic air embolism into the right coronary artery during a percutaneous CT-guided lung biopsy that was successfully recognized during the procedure and managed accordingly. An active search for this complication should be made when the patient deteriorates on table and the usual complications (pneumothorax, vasovagal shock, etc.) are ruled out, as immediate resuscitative measures could be life-saving.

Risk factors for coronary artery lesions in children with Kawasaki disease

Introduction

Kawasaki disease (KD) is a nonspecific systemic vasculitic disease that frequently occurs among children, and coronary artery lesion (CAL) is the most serious complication.

Objectives

We aimed to study the risk factors for CAL in children with KD.

Materials and methods

KD children in accordance with diagnostic criteria, who were hospitalized from January 2014 to December 2017, were selected as subjects. Univariate and multivariate logistic regression analyses were conducted to explore the relationships between CAL and gender, age, clinical diagnosis, erythrocyte sedimentation rate (ESR), platelet count, hemoglobin level, C reactive protein level, white blood cell count, initiation time of IVIG administration and duration of fever.

Results

The enrolled 982 KD children were divided into a CAL group (n = 104) and an NCAL group (n = 878) according to cardiac color Doppler ultrasonography. The incidence rate of CAL was 10.6 % (104/982). Univariate analysis showed that the two groups had significantly different gender, ESR, platelet count, initiation time of IVIG administration and duration of fever (P &#60; 0.05). Multivariate logistic regression analysis revealed that male gender, elevated ESR and delayed use of IVIG were independent risk factors for KD complicated with CAL.

Conclusions

Male gender, increased ESR and delayed use of IVIG were independent risk factors for KD complicated with CAL.

A Computationally Efficient Approach to Segmentation of the Aorta and Coronary Arteries Using Deep Learning

Early detection and diagnosis of coronary artery disease could reduce the risk of developing a heart attack. The coronary arteries are optimally visualised using computed tomography coronary angiography (CTCA) imaging. These images are reviewed by specialist radiologists who evaluate the coronary arteries for potential narrowing. A lack of radiologists in the UK is a constraint to timely diagnosis of coronary artery disease, particularly in the acute accident and emergency department setting. The development of automated methods by which coronary artery narrowing can be identified rapidly and accurately are therefore timely. Such complex computer based tools also need to be sufficiently computationally efficient that they can run on servers typically found in hospital settings, where graphical processing units for example are unavailable. We propose a fully automatic two-dimensional Unet model to segment the aorta and coronary arteries on CTCA images. Two models are trained to segment two regions of interest, (1) the aorta and the coronary arteries or (2) the coronary arteries alone. Our method achieves 91.20% and 88.80% dice similarity coefficient accuracy on regions of interest 1 and 2 respectively. Compared with a semi-automatic segmentation method, our model performs better when segmenting the coronary arteries alone. The performance of the proposed method is comparable to existing published two-dimensional or three-dimensional deep learning models. Importantly, the algorithmic and graphical processing unit memory efficiencies are maintained such that the model can be deployed without requiring graphical processing units, and therefore can be used in a hospital setting.

A Case of Anomalous Left Anterior Descending Artery Originating From the Right Sinus of Valsalva

The anomalous origin of coronary arteries has been extensively documented in the literature. Most of the anomalies are incidentally found either during coronary angiography or imaging studies and are usually benign; however, malignant outcomes have been reported in the literature. Here, we present the case of a 76-year-old male with non-ST segment elevation myocardial infarction who was found to have an asymptomatic anomalous origin left anterior descending artery from the right sinus of Valsalva.

Male Patients with Takayasu Arteritis and Coronary Artery Involvement are Prone to have Serious Coronary Stenosis and High Mortality

BACKGROUND

Takayasu arteritis (TAK) is a rare autoimmune vasculitis that predominantly affects the aorta and its major branches, including the coronary arteries. Limited information is available regarding sex-specific differences in coronary artery involvement among TAK patients.

OBJECTIVE

To assess the differences in coronary angiographic findings and the long-term outcomes between male and female TAK patients having coronary artery involvement.

METHODS

This retrospective cohort study included 87 TAK patients, grouped by sex, who underwent coronary angiography. General characteristics, clinical features, coronary angiographic findings, and therapeutic strategies were obtained from medical records. Major Adverse Cardiac Events (MACE), including death from any cause; myocardial infarction; repeated coronary artery revascularization; and rehospitalization due to unstable or progressive angina, or heart failure occurring during follow-up, were also recorded.

RESULTS

A total of 207 coronary lesions with stenosis were found in 87 TAK patients. The prevalence of ostial coronary lesions was lower in men than in women (9.1 vs. 23.9%, p=0.031). We observed less moderate stenosis (6.8 vs 22.7%, p=0.018) and more severe stenosis or occlusion (70.5 vs 46.0%, p=0.004) in the coronary lesions of male TAK patients. During the up to 7-year follow-up, death from any cause was greater in men than in women (21.4 vs. 1.5%, p=0.003); no other significant differences in MACE occurrence were observed between sexes.

CONCLUSIONS

Among TAK patients with coronary artery involvement, males tend to have more severe coronary stenosis and a higher risk for long-term mortality than females.

Ordered multi-path propagation for vessel centerline extraction

Vessel centerline extraction from x-ray angiography images is essential for vessel structure analysis in the diagnosis of coronary artery disease. However, complete and continuous centerline extraction remains a challenging task due to image noise, poor contrast, and complexity of vessel structure. Thus, an iterative multi-path search framework for automatic vessel centerline extraction is proposed. First, the seed points of the vessel structure are detected and sorted by confidence. With the ordered seed points, multi-bifurcation centerline is searched through multi-path propagation of wavefront and accumulated voting. Finally, the centerline is further extended piecewise by wavefront propagation on the basis of keypoint detection. The latter two steps are performed alternately to obtain the final centerline result. The proposed method is qualitatively and quantitatively evaluated on 1260 synthetic images and 50 clinical angiography images. The results demonstrate that our method has a highF1score of 87.8% ± 2.7% for the angiography images and achieves accurate and continuous results of vessel centerline extraction.

The Effects of Melatonin on the Oxidative Stress and Duration of Atrial Fibrillation after Coronary Artery Bypass Graft Surgery: A Randomized Controlled Trial

BACKGROUND

Atrial Fibrillation (AF) is a common complication following Coronary artery bypass graft (CABG) Surgery, which may be due to oxidative stress, necrosis and inflammation during CABG and can lead to increases the length of hospital stay and the risk of morbidity and mortality. Melatonin is a hormone with anti-oxidant and anti-inflammatory properties in the cardiovascular system. This study assessed the efficacy of sublingual consumption of melatonin in reducing necrosis and inflammation, in patients undergoing CABG with respect to C-reactive protein (hs-CRP), Creatine Kinase-Muscle-Brain subunits (CK-MB) and cardiac Troponin T (cTnT) levels.

METHODS

One hundred and two patients were enrolled and twenty-six patients were excluded during the study process and finally seventy-six patients undergoing CABG surgery randomly assigned to melatonin group (n = 38, 12 mg sublingual melatonin the evening before and 1 hour before surgery, or the control group which did not receive Melatonin, n = 38). Three patients in the melatonin group and three patients in the control group were excluded from the study because of discontinued intervention and lost to follow up. The samples were collected before and 24 hours after surgery. hs-CRP, CK-MB, and cTnT levels were measured in all patients with the Elisa method.

RESULTS

There was no significant difference in influencing variables among the groups at the baseline. The incidence of AF following CABG surgery was not statistically significant between the two groups, (p-value = 0.71). However, the duration of AF (p-value = 0.01), the levels of hs-CRP (p-value = 0.001) and CK-MB (p-value = 0.004) measured, 24 hours after surgery were significantly lower in the melatonin group. cTnT levels measured 24 hours post-CABG did not show any significant difference in both groups (p-value = 0.52).

CONCLUSION

Our findings suggest that the administration of melatonin may help modulate oxidative stress, based on the reduction of the levels of hs-CRP, CK-MB, and the duration of AF following CABG surgery.

Evaluation of the morphological and clinical features of left anterior descending myocardial bridging with multi-detector computed tomography

Aim

The aim of the study was to assess the incidence, localization, depth, length of myocardial bridging (MB) with left anterior descending (LAD), systolic compression ratio, atherosclerotic plaque localization and degree of stenosis by 256-slice multi-detector computed tomography (MDCT).

Material and methods

Computed tomography (CT) scans from a total of 3947 patients who underwent MDCT were reviewed retrospectively for LAD MB. A diastolic and systolic dataset with the best image quality was selected. Myocardial bridge was defined as a coronary artery with an intra-myocardial course. Myocardial bridging was divided into “deep” or “superficial”. The length and depth of the bridging segment were calculated. For each bridging segment, the presence of atherosclerosis was saved in a 2-cm-long segment proximal to the entry of the bridging segment. The degree of stenosis made by atherosclerotic plaques was determined.

Results

LAD myocardial bridging was detected in 410 (10.4%) patients. Among these, 97 (23.7%) patients had a deep and 313 (76.3%) patients had a superficial course. The mean LAD MB length was 20.28 ±9.63 mm and the depth was 1.72 ±1.11 mm. The systolic and diastolic mean diameter difference was 0.193 mm and the average compression ratio was 9.44%. Atherosclerotic plaques were found in 167 (40.7%) of 410 LAD MB. Atherosclerotic plaques were found in 50.5% of deep MB and 37.7% of superficial MB.

Conclusions

256-slice MDCT coronary angiography has a high sensitivity to show myocardial bridging in LAD localization, to determine length, depth, compression ratio, atherosclerotic plaque localization and degree of stenosis.

Multiple Thrombectomies for Cerebral and Coronary Artery Occlusion in Trousseau Syndrome

Objective

Trousseau syndrome (TS) is a condition of systemic thrombosis generally associated with an underlying malignancy. An ischemic stroke is a representative thrombotic event. Thrombectomy is a useful procedure for the treatment of cerebral large vessel occlusion, and anticoagulation therapy is the main preventive treatment for TS. This case report describes a woman with terminal pancreatic tumor presenting with repeated occlusions of cerebral and coronary arteries necessitating multiple thrombectomies.

Case Presentation

A 67-year-old woman was admitted to our hospital with severe right hemiplegia and global aphasia. MRI revealed left M1 occlusion; therefore, a thrombectomy was performed. Her symptoms recovered completely. Body contrast CT revealed pancreatic cancer with multiple metastases, and she was diagnosed with TS. On day 4 after thrombectomy, the same neurological symptoms occurred and re-occlusion of the left M1 was confirmed. Endothelial injury was suspected, and thrombectomy was repeated. Despite continuing anticoagulation therapy, the coronary artery was occluded and she underwent percutaneous coronary intervention on day 13. To treat the primary pancreatic lesion, she was transferred to the Surgery unit on day 20.

Conclusion

Hypercoagulability associated with TS and endothelial damage due to rough procedure resulted in repeated vessel occlusions in this case. Careful thrombectomy and anticoagulation therapy with strict monitoring are needed in TS patients.

Smooth Muscle Specific Ablation of CXCL12 in Mice Downregulates CXCR7 Associated with Defective Coronary Arteries and Cardiac Hypertrophy

The chemokine CXCL12 plays a fundamental role in cardiovascular development, cell trafficking, and myocardial repair. Human genome-wide association studies even have identified novel loci downstream of the CXCL12 gene locus associated with coronary artery disease and myocardial infarction. Nevertheless, cell and tissue specific effects of CXCL12 are barely understood. Since we detected high expression of CXCL12 in smooth muscle (SM) cells, we generated a SM22-alpha-Cre driven mouse model to ablate CXCL12 (SM-CXCL12^−/−). SM-CXCL12^−/− mice revealed high embryonic lethality (50%) with developmental defects, including aberrant topology of coronary arteries. Postnatally, SM-CXCL12^−/− mice developed severe cardiac hypertrophy associated with fibrosis, apoptotic cell death, impaired heart function, and severe coronary vascular defects characterized by thinned and dilated arteries. Transcriptome analyses showed specific upregulation of pathways associated with hypertrophic cardiomyopathy, collagen protein network, heart-related proteoglycans, and downregulation of the M2 macrophage modulators. CXCL12 mutants showed endothelial downregulation of the CXCL12 co-receptor CXCR7. Treatment of SM-CXCL12^−/− mice with the CXCR7 agonist TC14012 attenuated cardiac hypertrophy associated with increased pERK signaling. Our data suggest a critical role of smooth muscle-specific CXCL12 in arterial development, vessel maturation, and cardiac hypertrophy. Pharmacological stimulation of CXCR7 might be a promising target to attenuate adverse hypertrophic remodeling.

Ifetroban reduces coronary artery dysfunction in a mouse model of Duchenne muscular dystrophy

Dilated cardiomyopathy contributes to morbidity and mortality in Duchenne muscular dystrophy (DMD), an inheritable muscle-wasting disease caused by a mutation in the dystrophin gene. Preclinical studies in mouse models of muscular dystrophy have demonstrated reduced cardiomyopathy and improved cardiac function following oral treatment with the potent and selective thromboxane A₂/prostanoid receptor (TPr) antagonist ifetroban. Furthermore, a phase 2 clinical trial (NCT03340675, Cumberland Pharmaceuticals) is currently recruiting subjects to determine whether ifetroban can improve cardiac function in patients with DMD. Although TPr is a promising therapeutic target for the treatment of dilated cardiomyopathy in DMD, little is known about TPr function in coronary arteries that perfuse blood through the cardiac tissue. In the current study, isolated coronary arteries from young (∼3-5 mo) and aged (∼9-12 mo) mdx mice, a widely used mouse model of DMD, and age-matched controls were examined using wire myography. Vasoconstriction to increasing concentrations of TPr agonist U-46619 (U4) was enhanced in young mdx mice versus controls. In addition, young mdx mice displayed a significant attenuation in endothelial cell-mediated vasodilation to increasing concentrations of the muscarinic agonist acetylcholine (ACh). Since TPr activation was enhanced in young mdx mice, U4-mediated vasoconstriction was measured in the absence and the presence of ifetroban. Ifetroban reduced U4-mediated vasoconstriction in young mdx mice and both aged mdx and control mice. Overall, our data demonstrate enhanced coronary arterial vasoconstriction to TPr activation in young mdx mice, a phenotype that could be reversed with ifetroban. These data could have important therapeutic implications for improving cardiovascular function in DMD.NEW & NOTEWORTHY This investigation revealed 1) impaired acetylcholine-mediated vasodilation, 2) increased U-46619-mediated vasoconstriction, and 3) reversal of the increase in U-46619-mediated vasoconstriction by the thromboxane A₂/prostanoid receptor (TPr) antagonist ifetroban in left anterior descending coronary arteries isolated from young mdx mice, a model of Duchenne muscular dystrophy (DMD). Ifetroban has been used in preclinical studies to demonstrate improved cardiac function in mouse models of muscular dystrophy and is currently being investigated in a phase 2 clinical trial in patients with DMD. The current study supports the role of ifetroban in improving coronary artery function in preclinical DMD models, which may contribute to improved cardiovascular health.

Apelin Does Not Impair Coronary Artery Relaxation Mediated by Nitric Oxide-Induced Activation of BKCa Channels

Apelin-APJ receptor signaling regulates vascular tone in cerebral and peripheral arteries. We recently reported that apelin inhibits BK_Ca channel function in cerebral arteries, resulting in impaired endothelium-dependent relaxations. In contrast, apelin causes endothelium-dependent relaxation of coronary arteries. However, the effects of apelin on BK_Ca channel function in coronary arterial myocytes have not yet been explored. We hypothesized that apelin-APJ receptor signaling does not have an inhibitory effect on coronary arterial BK_Ca channels and hence does not alter nitric oxide (NO)-dependent relaxation of coronary arteries. Patch clamp recording was used to measure whole cell K⁺ currents in freshly isolated coronary smooth muscle cells. Apelin had no effect on the increases in current density in response to membrane depolarization or to NS1619 (a BK_Ca channel opener). Moreover, apelin did not inhibit NO/cGMP-dependent relaxations that required activation of BK_Ca channels in isolated coronary arteries. Apelin-APJ receptor signaling caused a marked increase in intracellular Ca²⁺ levels in coronary arterial smooth muscle cells, but failed to activate PI3-kinase to increase phosphorylation of Akt protein. Collectively, these data provide mechanistic evidence that apelin has no inhibitory effects on BK_Ca channel function in coronary arteries. The lack of inhibitory effect on BK_Ca channels makes it unlikely that activation of APJ receptors in coronary arteries would adversely affect coronary flow by creating a vasoconstrictive environment. It can be expected that apelin or other APJ receptor agonists in development will not interfere with the vasodilator effects of endogenous BK_Ca channel openers.

Imaging and Targeting Coronary Artery Inflammation

Significance: Coronary artery disease (CAD) continues to be a leading cause of morbidity and mortality across the world despite significant progress in the prevention, diagnosis, and treatment of atherosclerotic disease. Recent Advances: The focus of the cardiovascular community has shifted toward seeking a better understanding of the inflammatory mechanisms driving residual CAD risk that is not modulated by current therapies. Significant progress has been achieved in revealing both proinflammatory and anti-inflammatory mechanisms, and how shift of the balance in favor of the former can drive the development of disease. Critical Issues: Advances in the noninvasive detection of coronary artery inflammation have been forthcoming. These advances include multiple imaging modalities, with novel applications of computed tomography both with and without positron emission tomography, and experimental ultrasound techniques. These advances will enable better selection of patients for anti-inflammatory treatments and assessment of treatment response. The rapid advancement in pharmaceutical design has enabled the production of specific antibodies against inflammatory pathways of atherosclerosis, with modest success to date. The pursuit of demonstrating the efficacy and safety of novel anti-inflammatory and/or proinflammatory resolution therapies for atherosclerotic CAD has become a major focus. Future Directions: This review seeks to provide an update of the latest evidence of all three of these highly related but disparate areas of inquiry: Our current understanding of the key mechanisms by which inflammation contributes to coronary artery atherosclerosis, the evidence for noninvasive assessment of coronary artery inflammation, and finally, the evidence for targeted therapies to treat coronary inflammation for the reduction of CAD risk. Antioxid. Redox Signal. 34, 1217-1243.

LncRNA Landscape of Coronary Atherosclerosis Reveals Differentially Expressed LncRNAs in Proliferation and Migration of Coronary Artery Smooth Muscle Cells

We aimed to investigate differentially expressed long non-coding RNAs (lncRNAs) and messenger RNAs (mRNAs) in atherosclerosis and validate the expression of lncRNAs and co-expressed target genes in proliferation and migration models of human coronary artery smooth muscle cells (HCASMCs). Ten coronary artery specimens from a subject who died from a heart attack were employed. The pathological analysis was analyzed by hematoxylin and eosin (H&E) staining, and the lncRNAs and mRNAs were identified by RNA sequencing. Bioinformatic analyses were performed to predict possible mechanisms. The proliferation and migration of HCASMCs were induced with oxidized low-density lipoprotein (ox-LDL). Differentially expressed lncRNAs and mRNAs were validated by quantitative real-time polymerase chain reaction (qRT-PCR). In this study, 68 lncRNAs and 222 mRNAs were identified differentially expressed in atherosclerosis. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses showed that the Fanconi anemia pathway may be involved in atherosclerosis. GON4L was found to be the co-localized target gene of LNC_000439, and 14 genes had high correlations with the expression of seven lncRNAs. In addition, nine lncRNA–miRNA–mRNA networks were constructed, and 53 co-expressed gene modules were detected with weighted gene co-expression network analysis (WGCNA). LNC_000684, LNC_001046, LNC_001333, LNC_001538, and LNC_002115 were downregulated, while LNC_002936 was upregulated in proliferation and migration models of HCASMCs. In total, six co-expressed mRNAs were upregulated in HCASMCs. This study suggests that the differentially expressed lncRNAs identified by RNA sequencing and validated in smooth muscle cells may be a target for regulating HCASMC proliferation and migration in atherosclerosis, which will provide a new diagnostic basis and therapeutic target for the treatment of cardiovascular diseases.