Evaluation Of Acute Aortic Dissection Research Articles

Identification of Serum Biomarker in Acute Aortic Dissection by Global and Targeted Metabolomics

Acute aortic dissection (AAD) is the most devastating aortic pathology, and the incidence is increasing worldwide. However, the occurrence and development of AAD are unpredictable. A thorough understanding of the serum metabolic landscape through metabolomic analysis may help identify new biomarkers for AAD and offers new insights into its prevention and evaluation. Nineteen patients with Stanford type A aortic dissection and 20 healthy individuals were enrolled in this study. We use global and targeted mass spectrometry-based metabolomics to investigate the serum metabolomics profiles, and the data were analyzed by principal component analysis and orthogonal partial least squares discriminant analysis. Initial untargeted metabolomics analysis revealed significant changes of lipids and polar metabolites in patients with AAD. Alterations of the phosphatidylcholine metabolic pathway were further observed by targeted metabolomics. Trimethylamine N-oxide (TMAO) levels were obviously increased in patients with AAD compared with controls (P<0.005), whereas the levels of carnitine (P<0.005), choline, and betaine (P<0.05) were decreased. Furthermore, TMAO levels were associated with disease severity in AAD and correlated positively with C-reactive protein levels (r=0.537, P=0.018), IL-6 levels (r=0.546, P=0.016), D-dimer levels (r=0.694, P=0.001), and maximum aortic diameter on admission (r=0.748, P=0.002). Patients with AAD showed a predominant and consistent change of metabolites levels, especially the compounds in the phosphatidylcholine metabolic pathway. TMAO could potentially serve as a biomarker for the auxiliary diagnosis and evaluation of AAD.

Characterization of Aortic Dissection: What the Radiologist Needs to Know

Evaluation of acute aortic dissection by computed tomography angiography provides detailed characterization of this disease beyond the Stanford classification. Recent publications based on large patient registries and other sources have identified morphological characteristics that impact patient prognosis, and advanced understanding of both the incidence and demographics of this disease. This article reviews the recent literature and discusses the importance of imaging findings, such as aortic/false lumen diameter, signs of organ malperfusion, false lumen thrombosis, and characterization of intimal tears. The associated entity acute intramural hematoma is discussed, as well as imaging features that predict adverse outcomes. Familiarity with these imaging characteristics maximizes the utility of radiographic evaluation in this disease.

Simultaneous examination of the aorta in echocardiography of patients with coronary artery disease

The majority of aortic aneurysms are asymptomatic and are discovered incidentally on routine physical examination or on imaging studies for other indications [1], although the rupture of the aortic aneurysm can cause uncontrolled hemorrhage and rapid circulatory collapse. Atherosclerosis has been considered the underlying cause of aortic aneurysms, and the concomitant disorder of aortic aneurysm and coronary artery disease can be frequently observed [2]. Echocardiography is a basic modality to assess patients with coronary artery disease and can be used for the screening of aortic aneurysm. I would like to recommend the simultaneous examination of the aorta in the echocardiography of patients with coronary artery disease and propose the following screening method for aortic aneurysms. (1) Superior intercostal view (Fig. 1): left parasternal approach is a standard method for the long-axis view of the left ventricle, atrium, and proximal ascending aorta. The approach from the superior intercostal space can visualize the proximal to mid-portion of the ascending aorta. (2) Small-scale longaxis view (Fig. 2): the descending aorta can be seen behind the left atrium in the parasternal view of echocardiography by adjusting the window depth. (3) Subxiphoid view: abdominal aorta can be seen from subxiphoid and abdominal approaches. (4) Suprasternal view (Fig. 3): aortic arch to proximal descending aorta can be illuminated from the suprasternal approach on the ‘‘sniff’’ and supine position. These approaches may be recalled as the ‘‘four Ss’’. The routine evaluation of the aorta in echocardiography must make the time required for aortic echo shorter. Quick aortic echo using the four S approaches will be able to play an important role not only in the search for aortic aneurysm, but also in the evaluation of acute aortic dissection in the emergency room.

Evaluation of acute aortic dissection by cine-MRI.

We investigated operative indication of acute aortic dissection by analyzing the movement of the intimal flap using cine-MRI. Ten consecutive cases of acute aortic dissection diagnosed between December 1997 and September 1998 participated in this study. Six of these patients had in Stanford type A and four Stanford type B aortic dissection. The diagnosis of aortic dissection was based on demonstration of two aortic channels with each cardiac cycle. After obtaining SE(spin-echo) images, gradient echo sequences (FFE) were obtained such that the false lumen was maximally imaged and the intimal flap was depicted perpendicularly. During one RR-interval of ECG, 12 to 16 measurements were recorded and combined in a cineloop mode. We defined the intimal flap, the site of the entry and thrombosis in the false lumen, and evaluated the movement of the intimal flap as the flap movement index (FMI). Maximum and minimum aortic diameters (ADmax, ADmin), as well as maximum and minimum false lumen diameters (FDmax, FDmin) were measured. FMI was defined as[(FDmax/ADmax) - (FDmin/ADmin)]/(FDmin/ADmin) x 100(%). Total thrombosis was noted in four cases, partial thrombosis in 3, and in the remaining 3 no thrombosis of the false lumen was noted. The FMI ranged between 4% and 87% (mean 26.3 +/- 8.6%). Among the 4 cases with the large FMI of greater than 30%, 3 underwent emergency surgery and were confirmed to have no thrombosis in the false lumen. The fourth case, who had partial thrombosis, underwent medical therapy, but since complete thrombosis in the false lumen never did occur in this case, surgery became absolutely necessary. The other 6 cases with a FMI of less than 30% showed a tendency toward gradual reduction of the false lumen. FMI is a potentially useful parameter in cases with acute aortic dissection to determine whether or not emergency surgery is indicated.

Evaluation of Acute Aortic Dissection by Use with Gadolinium Enhanced MR Angiogra p hy: Comparison withSpin-echo MR Image

Purpose: To compare the usefulness of Gadolinium-enhanced MR angiography(Gd-MRA) with spin-echo(SE) MRI for the evaluation of acute aortic dissection. Materials and Methods: During a recent one-year period were trospectively reviewed the results of SE MRI and Gd-MRA in 14 patients (10 males, 4 females; mean age 57 years)with acute aortic dissection. DeBakey type I was found in six patients, DeBakey type II in one, and DeBakey typeIII in seven. MR techniques were as follows. First, multislice multiphase images were obtained in axial, coronal and oblique sagittal planes using SE T1WI(TR/TE/flip angle=600/14/90; acquisition time=25min), and images of selected slices were obtained using breath-hold turbo SE T2WI(TR/TE/flip angle=800/76/160). Second, breath-holdGd-MRA imaging (3D-FISP; TR/TE/Flip angle=4.2/1.7/25; acquisition time=1min) was performed, with oblique sagittal(arch view) orientation. We compared 14 SE MRI images with nine thoracic and five abdominal Gd-MRA images, evaluating the presence and extent of intimal flap, entry and reentry tear, thrombus in false lumen (and comparison to true lumen), the involvement of major branching vessels of the aortic arch, the origin of majorabdominal branching vessels, the presence of hemothorax and hemopericardium. Results : Both SE MRI and Gd-MRA very accurately detected the extent of intimal flap, and false lumen status. For detecting the site of entry tear, and the involvement of major branching vessels at the aortic arch, Gd-MRA(n=12) was more accurate than SE MRI(n=7).When used to image 20 vessels in five patients, Gd-MRA identified with perfect accuracy the origin of majorabdominal branching vessels; SE MRI, however, demonstrated only six of 20 vessels. SE MRI, however, was muchsuperior for the identification of complications such as hemothorax(n=9) and hemopericardium(n=2); in thisrespect, Gd-MRA failed completely. Conclusion: For the evaluation of patients with acute aortic dissection, Gd-MRAprovides information regarding site of entry tear and the involvement of major branching vessels very much fasterthan SE-MRI. In such cases, Gd-MRA can therefore be used for initial investigatory imaging.

Intravascular ultrasound evaluation of acute aortic dissection in canines and a human

Intravascular ultrasound evaluation of acute aortic dissection in canines and a human

Evaluation of Acute Aortic Dissection by Intravascular Ultrasonography

Evaluation of Acute Aortic Dissection by Intravascular Ultrasonography

Thoracic aortic dissection: pitfalls and artifacts in MR imaging.

Results of 53 thoracic magnetic resonance (MR) imaging examinations were reviewed to determine the prevalence and severity of artifacts and pitfalls that may occur in the evaluation of acute aortic dissection. Grade 1 artifacts and pitfalls were mimics of aortic dissection on individual images but could be demonstrated not to represent a dissection when other images from the same sequence were evaluated. Grade 2 artifacts and pitfalls required the use of images from other planes or sequences to distinguish them from a dissection. Grade 3 artifacts and pitfalls could not be distinguished from a dissection without the use of other imaging modalities. Of the 53 cases examined, 34 (64%) had artifacts or pitfalls of grade 1 or higher, 10 (19%) had artifacts or pitfalls of grade 2 or higher, and one case (2%) had grade 3 artifacts or pitfalls. Sixteen cases had more than one artifact or pitfall. Pitfalls and artifacts that mimic aortic dissection occur in a significant percentage of thoracic MR imaging examinations. An awareness of their existence, knowledge of normal anatomy, the use of axial images in all cases with the addition of images in other planes as needed, rotation of phase and frequency gradients as needed, and clinical correlation may avert misinterpretation in nearly all cases.