Multi-detector computed tomography in the diagnosis and management of acute aortic syndromes

Acute aortic syndrome(AAS) is a spectrum of conditions, which may ultimately progress to potentially life-threatening aortic rupture. This syndrome encompasses aortic dissection(AD), intramural haematoma, penetrating atherosclerotic ulcer and unstable thoracic aortic aneurysms. Multi-detector CT(MDCT) is crucial for the diagnosis of AAS, especially in the emergency setting due to its speed, accuracy and ready availability. This review attends to the value of appropriate imaging protocols in obtaining good quality images that can permit a confident diagnosis of AAS. AD is the most commonly encountered AAS and also the one with maximum potential to cause catastrophic outcome if not diagnosed and managed promptly. Hence, this review briefly addresses certain relevant clinical perspectives on this condition. Differentiating the false from the true lumen in AD is often essential; a spectrum of CT findings, e.g., "beak sign", aortic "cobwebs" that allows such differentiation have been described with explicit illustrations. The value of non enhanced CT scans, especially useful in the diagnosis of an intramural hematoma has also been illustrated. Overlap in the clinical and imaging features of the various conditions presenting as AAS is not unusual. However, on most instances MDCT enables the rightdiagnosis. On select occasions MRI or trans-esophageal echocardiography may be required as a problem solving tool.

Angiograms of the Abdominal Aorta in a Patient of Middle Aortic Syndrome

A 42-year old woman of middle aortic syndrome presented with severe hypertension for 20 years, whose abdominal aorta angiography revealed long segment and nearly complete occlusion in the mid portion of abdominal aorta, and extensively enlarged collateral vascular supply to the lower portion of abdominal aorta. The pressures proximal and distal to stenosis were 185/110 and 95/70 mmHg, and the pressure gradient across the stenosis was 90/40 mmHg. After the operation of thoraco-abdominal bypass graft, the pressure difference between the upper and lower extremities eventually disappeared.

Misdiagnosed coronary artery disease-acute aortic syndrome： A case report

It is estimated that 15% of traffic accidents cause trauma to large vessels. In about 70%-95% of cases, aortic rupture took place in the distal ligament of the left subclavian artery, whereas in the remaining cases rupture occurred in the ascending aorta above the aortic valve. Trauma to the aortic sinus and coronary arteries is rarely found in traffic accident victims. Therefore, coronary artery trauma is often misdiagnosed as coronary atherosclerotic heart disease. The present case is a 42 years old male who survived from a traffic accident. He presented with aortic sinus and left coronary artery trauma. He was misdiagnosed as having coronary atherosclerotic heart disease, and therefore wrongly given antiplatelet medicine, such as aspirin, in another hospital. Definite diagnosis was achieved in our hospital, and the patient underwent Bentall and mitral valve replacement, as well as tricuspid valvuloplasty. The aortic occlusion time during surgery was 47 min, and the total cardiopulmonary bypass time was 63 rain. After surgery, transthoracic echocardiography confirmed that all the artificial valves worked sufficiently. The patient felt good and symptoms such as asthma and decreased exercise tolerance disappeared. This case taught us that acute aortic syndrome cannot be ignored when patients present with pectoralgia; antiplatelet medication should not be given before definite diagnosis.

Correlation between C-reactive Protein and Morphology of Aortic Intramural Hematoma on CT Angiography

Objectives To investigate the morphologic characteristics of intramural hematoma(IMH)on CT angiography(CTA),and evaluate the possible correlation of serum C-reactive protein(CRP)with morphologic characteristics of IMH.Material and Methods Forty-two patients who were initially diagnosed as IMH by aortic CTA and also had serum CRP examination on the same day of CTA were enrolled in this retrospective study,including 30 males and 12 females,with the mean age of 61±14 years old.The volumetric CT data were retrospectively processed and analyzed on post-processing workstation.Based on the thickness of IMH and the length-area curve,the crosssectional area of true lumen and total vessel were measured,the hematoma-vessel ratio(HVR)was calculated.Imaging characteristics were compared between patients who had pathological elevated CRP(>0.8 mg/dl)and those did not.Spearman correlation analyses of CRP level and morphological characteristics of IMH were performed,and the receiver operating characteristic(ROC)curve was used to evaluate the diagnostic validity of CRP.Results Of all 42 IMH patients,the mean serum CRP was 3.94±4.71 mg/dl,and the mean HVR was 46.7%±14.2%.HVR in patients with elevated CRP was significantly higher than those with normal CRP(49.7%±15.0%vs.40.7%±10.5%,P=0.030).HVR was mildly correlated with CRP in all patients(r=0.48,P<0.001).CRP levels differed neither between patients with Stanford type A and B(P=0.207),nor between patients with and without intimal disruption(P=0.230).To discriminate HVR>47%(the mean value),the area under curve(AUC)were 0.700(95%CI:0.535-0.865)for CRP at a cutoff point of 3.55 mg/dl,with a sensitivity of 54.5%and a specificity of 90.0%.Conclusion CRP was mildly correlated with the severity of cross-sectional hematoma area of IMH,but not with Stanford types and the presence of intimal disruption.

Triple rule-out computed tomography angiography:Evaluation of acute chest pain in COVID-19 patients in the emergency department

BACKGROUND The aim of this study was to define clinical evidence supporting that triple ruleout computed tomography angiography(TRO CTA)is a comprehensive and feasible diagnostic tool in patients with novel coronavirus disease 2019(COVID-19)who were admitted to the emergency department(ED)for acute chest pain.Optimizing diagnostic imaging strategies in COVID-19 related thromboembolic events,will help for rapid and noninvasive diagnoses and results will be effective for patients and healthcare systems in all aspects.AIM To define clinical evidence supporting that TRO CTA is a comprehensive and feasible diagnostic tool in COVID-19 patients who were admitted to the ED for acute chest pain,and to assess outcomes of optimizing diagnostic imaging strategies,particularly TRO CTA use,in COVID-19 related thromboembolic events.METHODS TRO CTA images were evaluated for the presence of coronary artery disease,pulmonary thromboembolism(PTE),or acute aortic syndromes.Statistical analyses were used for evaluation of significant association between the variables.A two tailed P-value<0.05 was considered statistically significant.RESULTS Fifty-three patients were included into the study.In 31 patients(65.9%),there was not any pathology,while PTE was diagnosed in 11 patients.There was no significant relationship between the rates of pathology on CTA and history of hypertension.On the other hand,the diabetes mellitus rate was much higher in the acute coronary syndrome group,particularly in the PTE group(8/31=25.8%vs 6/16=37.5%,P=0.001).The rate of dyslipidemia was significantly higher in the group with pathology on CTA while compared to those without pathology apart from imaging findings of the pneumonia group(62.5%vs 38.7%,P<0.001).Smoking history rates were similar in the groups.Platelets,D-dimer,fibrinogen,C-reactive protein,and erythrocyte sedimentation rate values were higher in COVID-19 cases with additional pathologies.CONCLUSION TRO CTA is an effective imaging method in evaluation of all thoracic vascular systems at once and gives accurate results in COVID-19 patients.

Penetrating Atherosclerotic Ulcer with Elevated Troponin in A Patient with Old Myocardial Infarction: A Case Report

Penetrating atherosclerotic ulcer(PAU),an uncommon etiology of acute aortic syndrome(AAS),is a potential cause of chest pain seen in emergency departments.As PAU may lead to electrocardiogram(ECG)changes or rarely,elevated troponin levels,it is most likely misdiagnosed as acute coronary syndrome(ACS).Hence,individuals with PAU may be offered potentially life-threatening treatment.This paper reports a case of a 81-year-old male who presented with intermittent chest pain with a history of old inferior myocardial infarction and stent placement in the left circumflex coronary artery(LCX)three years ago.Initially,he was diagnosed with non-ST-elevation myocardial infarction(NSTEMI)based on abnormal ECG changes and raised troponin I.However,emergency coronary angiography(CAG)showed no restenosis in the left circumflex coronary artery(LCX)but with mild stenosis in the left anterior descending artery(LAD)and right coronary artery(RCA).Computed tomographic angiography(CIA)of the whole aorta showed multiple atherosclerotic plaques with penetrating atherosclerotic ulcer in the aortic arch and descending aorta.Endovascular aortic repair with Ankura II covered stent was performed.This case study reminds us that it is clinically difficult to distinguish PAU from ACS.Upon excluding ACS from the diagnosis,we should take into consideration of PAU,especially in elderly patients with positive cTnI.