Giant coronary fistula aneurysm presenting as a progressing left-sided asymptomatic mediastinal mass with systolic dominant Doppler flow: a case report

Background Cases of giant coronary artery aneurysms associated with coronary fistula are rarely reported, and they present with various symptoms, including coronary steal syndrome. We report an uncommon case of an asymptomatic giant coronary fistula aneurysm presenting as a progressing left-sided mediastinal mass that has been tracked for years. Case summary A 67-year-old healthy asymptomatic woman was referred to our hospital because of an abnormal shadow on her chest radiography revealing a left-sided mediastinal mass that had progressed in size over the past 4 years. Computed tomography revealed mass progression from 4 cm to 5 cm in diameter within 2 years. Coronary computed tomography and coronary angiography identified a giant coronary artery aneurysm in a coronary fistula originating in the left anterior descending artery and draining into the main pulmonary artery. Transthoracic Doppler echocardiography revealed a unique systolic-dominant flow. She underwent coronary artery aneurysmectomy and fistula ligation. The patient has been in good health without any events for 10 months since her discharge. Discussion A giant coronary artery aneurysm in a coronary fistula can present as an asymptomatic left-sided mediastinal mass that has progressed in size for years in older adults. Echocardiography can provide clues of the steal phenomenon in coronary artery fistula. A close investigation of mediastinal abnormalities can facilitate the detection of coronary aneurysms.

Characteristics and outcomes of cases of children and adolescents with pediatric inflammatory multisystem syndrome in a tertiary care centre in Mexico City.

Background: pediatric inflammatory multisystem syndrome (PIMS) is a complication of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in children that resembles Kawasaki syndrome and poses children at high risk of cardiorespiratory instability and/or cardiac damage. This study aims to describe the clinical presentation and outcomes of patients with PIMS in Mexico City. Methods: this was an observational study (May 1, 2020, to September 30, 2021) of children with PIMS according to Centers of Disease Control and Prevention case definition criteria, hospitalized in a single tertiary care pediatric center in Mexico City. Demographic characteristics, epidemiological data, medical history, laboratory tests, cardiology evaluations, treatment, and clinical outcomes were analyzed. Results: Seventy-five cases fulfilled case-definition criteria for PIMS (median age 10.9 years, IQR: 5.6-15.6). Fifteen (20%) had a severe underlying disease. Forty-eight cases (64%) were admitted to the intensive care unit, 33 (44%) patients required invasive mechanical ventilation, and 39 (52%) received vasopressor support. Two distinct groups of patients were identified: cluster 1 (n=60) who had rash or gastrointestinal symptoms and cluster 2 (n=15) with predominantly respiratory manifestations. Two cases (2.7%) died, both with severe underlying conditions. Five cases (6.7%) developed coronary aneurysms, all of them from cluster 1. Conclusion: clinical manifestations and outcomes are in general comparable what has been previously reported in international series. In our series, there was a high proportion of patients with severe respiratory involvement and positive RT-PCR SARS-CoV-2 and a low frequency of coronary aneurysms which suggests a possible higher proportion of children with severe acute COVID-19 in our included cases.

Recombinant Human Soluble Thrombomodulin Suppresses Arteritis in a Mouse Model of Kawasaki Disease

<b><i>Introduction and Objective:</i></b> Kawasaki disease (KD) is associated with diffuse and systemic vasculitis of unknown aetiology and primarily affects infants and children. Intravenous immunoglobulin (IVIG) treatment reduces the risk of developing coronary aneurysms, but some children have IVIG-resistant KD, which increases their risk of developing coronary artery injury. Here, we investigated the effect of recombinant human soluble thrombomodulin (rTM), which has anticoagulant, anti-inflammatory, and cytoprotective properties on the development of coronary arteritis in a mouse model of vasculitis. <b><i>Methods:</i></b> An animal model of KD-like vasculitis was created by injecting mice with <i>Candida albicans</i> water-soluble fraction (CAWS). This model was used to investigate the mRNA expression of interleukin (IL)-10, tumour necrosis factor alpha (TNF-α), and tissue factor (TF), in addition to histopathology of heart tissues. <b><i>Results:</i></b> rTM treatment significantly reduces cardiac vascular endothelium hypertrophy by 34 days after CAWS treatment. In addition, mRNA expression analysis revealed that rTM administration increased cardiac IL-10 expression until day 27, whereas expression of TNF-α was unaffected. Moreover, in the spleen, rTM treatment restores IL-10 and TF expression to normal levels. <b><i>Conclusion:</i></b> These findings suggest that rTM suppresses CAWS-induced vasculitis by upregulating IL-10. Therefore, rTM may be an effective treatment for KD.

Sex differences in treatment strategy for coronary artery aneurysms: Insights from the international Coronary Artery Aneurysm Registry

Introduction Sex disparities exist in coronary artery disease (CAD) in terms of risk profile, clinical management and outcome. It is unclear if differences are also present in coronary aneurysms, a rare variant of CAD. Methods Patients were selected from the international Coronary Artery Aneurysm Registry (CAAR; ClinicalTrials.gov: NCT02563626), and differences between groups were analysed according to sex. The CAAR database is a prospective multicentre registry of 1565 patients with coronary aneurysms (336 females). Kaplan-Meier method was used for event-free survival analysis for death, major adverse cardiac events (MACE: composite endpoint of death, heart failure and acute coronary syndrome) and bleeding. Results Female patients were older, were more often hypertensive and less frequently smoker. They were treated conservatively more often compared to male patients and received significantly less frequently aspirin (92% vs 88%, p = 0.002) or dual antiplatelet therapy (DAPT) (67% vs 58%, p = 0.001) at discharge. Median DAPT duration was also shorter (3 vs 9 months, p = 0.001). Kaplan-Meier analysis revealed no sex differences in death, MACE or bleeding during a median follow-up duration of 37 months, although male patients did experience acute coronary syndrome (ACS) more often during follow-up (15% vs 10%, p = 0.015). Conclusions These CAAR findings showed a comparable high-risk cardiovascular risk profile for both sexes. Female patients were treated conservatively more often and received DAPT less often at discharge, with a shorter DAPT duration. ACS was more prevalent among male patients; however, overall clinical outcome was not different between male and female patients during follow-up.

477 Three cases of Kawasaki disease developed at young age and with a long term follow-up

Kawasaki disease is a relatively new disease and it took years since its first discovery to find and establish precise diagnostic and therapeutic indications. We report three cases of Kawasaki disease diagnosed between 1976 and 1993, which developed vascular complications and which were followed up for more than 20 years. The first case involved a 45-year-old woman who was first diagnosed with Kawasaki disease at age 3 years old. Her condition was complicated in the acute phase by a myocardial infarction and by the development of an apical aneurysm. The second case involved a 30-years-old woman who was first diagnosed with Kawasaki disease at age 6 months. The disease was complicated by coronary aneurysms and by right coronary artery occlusion. The third case involved a 29-year-old male who received a diagnosis of Kawasaki disease at age 1 year old. Echocardiography in the acute phase showed coronary aneurysms. One year later a new echocardiography revealed a thrombosis of the right coronary artery without myocardial infarction. The coronarography confirmed the coronary aneurysms and the thrombosis. All three cases were treated with a medical therapy and were followed up with periodic imaging exams, stress tests, 24-h Holter monitorings and cardiological check-ups. With these three case reports we have highlighted the possibility of finding a population of adult patients who may come to medical attention for acute events, such as myocardial infarction, presenting complicated, and disastrous angiographic pictures: it is plausible that such a population, in addition to cardiovascular risk factors, may have developed a KD in the years of lacking diagnostic and therapeutic options.

472 Coronary disease in ADPKD patient: a giant coronary aneurysm

Aims Autosomal dominant polycystic kidney disease (ADPKD) is a monogenic disorder driven by mutation of one of two genes: PKD1, which codifies polycystin-1, and PKD2, which codifies polycystin-2. The mutated proteins determine the formation of multiple renal cysts with a consequent decline in kidney function eventually leading to end-stage renal disease (ESRD). In the last decades the cardiovascular complications of ADPKD are emerging as the leading cause of death, but coronary artery disease (CAD) remains to be an uncommon complication. Methods and results A 60-year-old male patient affected by ADPKD, in dialysis treatment for ESRD, was admitted in 2020 to our hospital for invasive coronary angiography (ICA), checking eligibility for kidney transplantation. He had a previous history of hypertension and chronic ischaemic cardiomyopathy. ICA performed in 2017 for unstable angina assessed ectasiant coronary arteries with diffuse atherosclerotic disease (Figure 1), determining significant stenosis of the proximal left anterior descending artery and proximal circumflex artery, treated with percutaneous coronary intervention (PCI). In 2020 was so repeated ICA, that evidenced a good result of the previous PCI, but pointed out a severe progression of ectasiant disease, which led to formation of giant aneurysm of the proximal tract of the right coronary artery, assessed at 3.8 cm × 2.5 cm (Figure 2), fistulizing to the right atrium and determining significant flow limitation in the following part of the right coronary artery. The absence of any symptoms and the lack of evidence of ongoing heart dysfunction, led our team to indicate conservative management and angiography follow-up. Conclusions Cardiovascular disease is a major cause of morbidity and death in ADPKD, underlying a tendency towards accelerated atherosclerosis, but wide data about coronary involvement are still lacking. ADPKD patients seem to have an increased risk of developing coronary aneurisms, but either due to the expression of mutated proteins in arterial smooth cells, to the accelerated atherosclerotic disease or to the combination of both, is still controversial. Consequently, it is difficult to differentiate the underlying pathophysiology of aneurysm formation in an individual patient and to speculate whether ADPKD patients have an increased risk of developing coronary aneurysms independent of their accelerated atherosclerotic process.

Mortality and clinical characteristics of multisystem inflammatory syndrome in children (MIS-C) associated with covid-19 in critically ill patients: an observational multicenter study (MISCO study)

Background The clinical presentation and severity of Multisystem Inflammatory Syndrome in Children associated with COVID-19 (MIS-C) is widespread and presents a very low mortality rate in high-income countries. This research describes the clinical characteristics of MIS-C in critically ill children in middle-income countries and the factors associated with the rate of mortality and patients with critical outcomes. Methods An observational cohort study was conducted in 14 pediatric intensive care units (PICUs) in Colombia between April 01, 2020, and January 31, 2021. Patient age ranged between one month and 18 years, and each patient met the requirements set forth by the World Health Organization (WHO) for MIS-C. Results There were seventy-eight children in this study. The median age was seven years (IQR 1-11), 18 % (14/78) were under one year old, and 56 % were male. 35 % of patients (29/78) were obese or overweight. The PICU stay per individual was six days (IQR 4-7), and 100 % had a fever upon arrival to the clinic lasting at least five days (IQR 3.7-6). 70 % (55/78) of patients had diarrhea, and 87 % (68/78) had shock or systolic myocardial dysfunction (78 %). Coronary aneurysms were found in 35 % (27/78) of cases, and pericardial effusion was found in 36 %. When compared to existing data in high-income countries, there was a higher mortality rate observed (9 % vs. 1.8 %; p=0.001). When assessing the group of patients that did not survive, a higher frequency of ferritin levels was found, above 500 ngr/mL (100 % vs. 45 %; p=0.012), as well as more cardiovascular complications (100 % vs. 54 %; p = 0.019) when compared to the group that survived. The main treatments received were immunoglobulin (91 %), vasoactive support (76 %), steroids (70.5 %) and antiplatelets (44 %). Conclusions Multisystem Inflammatory Syndrome in Children due to SARS-CoV-2 in critically ill children living in a middle-income country has some clinical, laboratory, and echocardiographic characteristics similar to those described in high-income countries. The observed inflammatory response and cardiovascular involvement were conditions that, added to the later presentation, may explain the higher mortality seen in these children.