Patrón de flujo en "4D Flow" y su vínculo con la aortopatía bicúspide / 4D Flow pattern and its role in bicuspid aortic valve aortopathy

ABSTRACT: Bicuspid aortic valve (BAV) disease is generally associated with thoracic aortic dilatation (TAD). Related factors include; genetical, morphological (valvular phenotype) and most recently, hemodynamic profiles associated with flow pattern and wall shear stress. Cardiac magnetic resonance 4D Flow (4DF) can give an integral evaluation of these later flow variables. Remarkable, different spectrums of flow and vortex direction exist in BAV that are related to the site of TAD (proximal or distal). Therefore, we present a 57 years old patient with BAV (Sievers 0) with anteroposterior leaflets distribution in which 4DF depicted an anteriorly and righthand oriented jet that correlated with the zone of grater AD; also, vortex rotation was counterclockwise, corresponding to the most frequent vortex type in BAV. In conclusion, 4DF is a powerful and ground-breaking tool that enhances our knowledge of BAV related aortopathy.

Screening for asymptomatic coronary artery disease in patients with type 2 diabetes mellitus

ABSTRACT Diabetes is a very frequent disease and it is estimated that its prevalence will continuously increase during the next two decades. The arteriosclerotic process in diabetic patients progresses earlier and more diffusely, and it is more accelerated in the diabetic patient than in the overall population. In diabetic subjects, acute myocardial infarction (AMI) and stroke are the leading causes of death, but the presence of arterial disease is not always detected before the development of the acute arterial event. Several times, AMI is asymptomatic or present nonspecific symptoms, and it is the initial form of presentation of coronary artery disease causing an important delay in initiating cardiovascular treatment in these patients. The purpose of this review article is to discuss how to screen and early diagnose the presence of coronary artery disease in asymptomatic diabetic patients, based on new available diagnostic resources. Currently, the most recommended technique used for screening coronary artery disease in these patients is myocardial perfusion scintigraphy or stress echocardiography because of greater sensitivity and specificity in relation to the exercise test. However, technological advances have enabled the development of new imaging diagnostic methods that are less invasive than conventional coronary angiography, and which gradually gain importance in the diagnosis of coronary artery disease as they show higher effectiveness with lower invasiveness and risk. Arch Endocrinol Metab. 2016;60(2):143-51.

Spontaneous Obliteration of Right Ventricular Pseudoaneurysm after Blunt Chest Trauma: Diagnosis and Follow-Up with Multidetector CT

Right ventricular (RV) pseudoaneurysm caused by trauma is very rare. We report a case of RV pseudoaneurysm which resolved without surgical treatment in a patient who survived a falling accident. Echocardiography failed to identify the pseudoaneurysm. Electrocardiography-gated CT showed a 17-mm-sized saccular pseusoaneurysm arsing from the RV outflow tract with a narrow neck. Follow-up CT after two months showed spontaneous obliteration of the lesion.

High-Definition Computed Tomography for Coronary Artery Stent Imaging: a Phantom Study

OBJECTIVE: To assess the performance of a high-definition CT (HDCT) for imaging small caliber coronary stents (< or = 3 mm) by comparing different scan modes of a conventional 64-row standard-definition CT (SDCT). MATERIALS AND METHODS: A cardiac phantom with twelve stents (2.5 mm and 3.0 mm in diameter) was scanned by HDCT and SDCT. The scan modes were retrospective electrocardiography (ECG)-gated helical and prospective ECG-triggered axial with tube voltages of 120 kVp and 100 kVp, respectively. The inner stent diameters (ISD) and the in-stent attenuation value (AVin-stent) and the in-vessel extra-stent attenuation value (AVin-vessel) were measured by two observers. The artificial lumen narrowing (ALN = [ISD - ISDmeasured]/ISD) and artificial attenuation increase between in-stent and in-vessel (AAI = AVin-stent - AVin-vessel) were calculated. All data was analyzed by intraclass correlation and ANOVA-test. RESULTS: The correlation coefficient of ISD, AVin-vessel and AVin-stent between the two observers was good. The ALNs of HDCT were statistically lower than that of SDCT (30 +/- 5.7% versus 35 +/- 5.4%, p < 0.05). HDCT had statistically lower AAI values than SDCT (15.7 +/- 81.4 HU versus 71.4 +/- 90.5 HU, p < 0.05). The prospective axial dataset demonstrated smaller ALN than the retrospective helical dataset on both HDCT and SDCT (p < 0.05). Additionally, there were no differences in ALN between the 120 kVp and 100 kVp tube voltages on HDCT (p = 0.05). CONCLUSION: High-definition CT helps improve measurement accuracy for imaging coronary stents compared to SDCT. HDCT with 100 kVp and the prospective ECG-triggered axial technique, with a lower radiation dose than 120 kVp application, may be advantageous in evaluating coronary stents with smaller calibers (< or = 3 mm).

CT Radiation Dose Optimization and Estimation: an Update for Radiologists

In keeping with the increasing utilization of CT examinations, the greater concern about radiation hazards from examinations has been addressed. In this regard, CT radiation dose optimization has been given a great deal of attention by radiologists, referring physicians, technologists, and physicists. Dose-saving strategies are continuously evolving in terms of imaging techniques as well as dose management. Consequently, regular updates of this issue are necessary especially for radiologists who play a pivotal role in this activity. This review article will provide an update on how we can optimize CT dose in order to maximize the benefit-to-risk ratio of this clinically useful diagnostic imaging method.