Fabiola Cartes-Zumelzu

Endovascular placement of a nitinol-ePTFE stent-graft for abdominal aortic aneurysms: Initial and midterm results

PURPOSE Because first-generation stent-grafts did not meet initial expectations, a recently designed nitinol-expanded polytetrafluoroethylene (ePTFE) stent-graft was tested for treatment of abdominal aortic aneurysms (AAAs) in a prospective clinical study. The primary study endpoints were technical success and safety. MATERIALS AND METHODS A nitinol-ePTFE self-expandable stent-graft (Excluder) was used to treat 72 patients with AAAs. The median follow-up period was 21.5 months +/- 13 (range, 1-46 mo). RESULTS Primary technical success in accurate placement of the device was achieved in 70 of 72 patients (97%). Complete exclusion of the aneurysm from arterial flow was achieved in 57 of 72 patients (79.2%). Three type I leaks were observed during implantation and were immediately corrected with a proximal cuff prosthesis in two patients. Fourteen of 72 patients (19.4%) had a type II leak. Major complications were observed in three patients (4.1%), including one death in the early postinterventional period (one of 72, 1.4%). At 3 months, aneurysms were excluded in 70 of 71 patients (98.6%), and at 12 months, aneurysms were occluded in 29 of 30 patients (96.7%). The maximum diameter of the aneurysm decreased from 55 mm +/- 11 (median +/- SD) before intervention to 53 mm +/- 13 at 6 and 12 months. None of the patients showed aneurysm growth. CONCLUSION This newly designed stent-graft proved to be effective and safe for treatment of AAAs.

Benefits of High-Pitch 128-Slice Dual-Source Computed Tomography for Planning of Transcatheter Aortic Valve Implantation

BACKGROUND Transcatheter aortic valve implantation (TAVI) has emerged as an alternative treatment for high-risk and inoperable patients. Advanced multimodality imaging, including computed tomography (CT), plays a key role for optimized planning of TAVI. METHODS Forty-nine patients (25 women; age, 82.3±8.8 year) with severe aortic stenosis scheduled for TAVI were examined with 128-slice high-pitch dual-source prospective aortoiliac CT angiography (CTA). The 3-coronary-sinus-alignment (3-CSA) plane, comprising left and right anterior oblique and craniocaudal projection, was defined from three-dimensional volume-rendered technique data sets and compared with the intraoperative angiographic plane (deployment plane) used for device implantation. A tolerance level of ±5-degree deviation was acceptable. Volume of intraoperative iodine contrast agent was compared before and after the implementation of the 3-CSA plane estimation by CT. RESULTS All 49 patients underwent TAVI, during which 6 CoreValves (Medtronic, Minneapolis, MN) and 43 Sapien valves (Edwards Lifesciences, Irvine, CA) were successfully implanted using transapical (n=29), transfemoral (n=17), and transaxillary access (n=4). No severe complications occurred. In 47 patients (96%), CTA correctly predicted the 3-CSA plane used for device implantation. Mean left anterior oblique by CTA was 5.3±6.5 degrees and craniocaudal was -1.3±10.1 degrees. Mean left anterior oblique deviation between CTA and the intraoperative projection was 2.1±2.7 degrees and craniocaudal was 1.7±3.0 degrees. Ostium heights of the right and left coronary arteries were 12±1.9 and 12.9±3.3 mm. No over-stenting occurred in left coronary artery ostia of 8 mm or more. Contrast volume was reduced from 81.8±25.6 to 59.4±40.2 mL (p=0.05) when using 3-CSA plane estimation by CT for final prosthesis implantation plane. CONCLUSIONS Aortoiliac high-pitch 128-slice dual-source CT contributes to TAVI planning, including reliable prediction of the 3-CSA valve deployment plane, which saves contrast volume during the procedure and may facilitate correct valve placement.

Carpal tunnel syndrome assessment with diffusion tensor imaging: Value of fractional anisotropy and apparent diffusion coefficient

AbstractObjectivesTo quantitatively assess carpal tunnel syndrome (CTS) with DTI by evaluating two approaches to determine cut-off values.MethodsIn forty patients with CTS diagnosis confirmed by nerve conduction studies (NCs) and 14 healthy subjects (mean age 58.54 and 57.8 years), cross-sectional area (CSA), apparent diffusion coefficient (ADC) and fractional anisotropy (FA) at single and multiple levels with intraobserver agreement were evaluated.ResultsMaximum and mean CSA and FA showed significant differences between healthy subjects and patients (12.85 mm2 vs. 28.18 mm2, p < 0.001, and 0.613 vs. 0.524, p=0.007, respectively) (10.12 mm2 vs. 19.9 mm2, p<0.001 and 0.617 vs. 0.54, p=0.003, respectively), but not maximum and mean ADC (p > 0.05). For cut-off values, mean and maximum CSA showed the same sensitivity and specificity (93.3 %). However, mean FA showed better sensitivity than maximum FA (82.6 % vs. 73.9 %), but lower specificity (66.7 % vs. 80 %), and significant correlation for maximum CSA, 97 % (p < 0.01), with good correlation for maximum ADC and FA, 84.5 % (p < 0.01) and 62 % (p=0.056), respectively.ConclusionsCSA and FA showed significant differences between healthy subjects and patients. Single measurement at maximum CSA is suitable for FA determination. Key Points • DTI showed that FA is stronger than ADC for CTS diagnosis.• Single- and multiple-level approaches were compared to determine FA and ADC. • Single-level evaluation at the thickest MN cross-sectional area is sufficient.

Two K versus 4 K storage phosphor chest radiography: detection performance and image quality

The purpose of this study was to evaluate the effect of matrix size (4-K versus 2-K) in digital storage phosphor chest radiographs on image quality and on the detection of CT-proven thoracic abnormalities. In 85 patients who underwent a CT of the thorax, we obtained two additional posteroanterior storage phosphor chest radiographs, one with a matrix size of 3,520×4,280 (=4-K) and the other with a matrix size of 1,760×2,140 (=2-K). Acquisition, processing and presentation parameters were identical for all radiographs. Two radiologists evaluated the presence of mediastinal, pleural, and pulmonary abnormalities on hard copies of the radiographs, applying ROC analysis. In addition, four radiologists were asked to subjectively rank differences in image quality and to assess the demarcation of anatomic landmarks comparing the images in a blinded side-by-side manner. These data were analyzed using a two-sided binomial test with a significance level of P<0.05. Both tests, the ROC analysis of the detection performance and the binomial test of the subjective quality ratings, did not reveal significant differences between the two matrix sizes. Compared to 2-K radiographs, 4-K storage phosphor chest radiographs do not provide superior detection performance or image quality when evaluated in identical hard copy formats.

Behandlung von thorakalen Aortenaneurysmen mit selbstexpandierenden endoluminalen Gefäßprothesen

ZusammenfassungGrundlagen: Die Studie wurde durchgeführt, um die Wertigkeit von endoluminalen selbstexpandierenden Gefäßprothesen (i.e. Stents) in der Therapie von Aneurysmen der descendierenden Aorta zu überprüfen. Methodik: 17 Patienten mit einem Aneurysma der Aorta thoracalis descendens von über 6 cm wurden mit einem Stent behandelt. Das Stent-Graft-System wurde über die A. femoralis bzw. A. iliaca oder Aorta abdominalis in die thorakale Aorta vorgeschoben und unter radiologischer Kontrolle zur Entfaltung gebracht. Ergebnisse: Eine erfolgreiche Positionierung der Stentprothese gelang in allen Fällen. Zur Exklusion des Aneurysmas waren pro Patient 1 bis 6 Stents notwendig (mittel: 2,8 Stents). Um ein sicheres Absetzten der Gefäßprothese zu gewährleisten, wurde bei 8 Patienten (47 %) eine Transposition der A. subclavia sin. auf die A. carotis communis sin. dem Stenting vorgeschaltet. Der vaskuläre Zugang wurde bei 6 Patienten über die A. femoralis, bei 6 Patienten über die A. iliaca und bei 5 Patienten über die Aorta abdominalis gewählt. Bei 3 Patienten konnte ein Stent-Leak nachgewiesen werden, welches bei 2 Patienten intraoperativ durch ein Re-Stenting behoben werden konnte. Die intraoperative Letalität betrug 0 %. Zwei Patienten (2/17=11,8 %) verstarben am 2. bzw. am 3. postoperativen Tag aufgrund einer Aneurysmenruptur bzw. aufgrund einer Minderperfusion des Truncus coeliacus mit nachfolgendem Multiorganversagen. Schlußfolgerungen: Die Implantation von Stent-Grafts stellt eine zukunftsweisende und wenig invasive Methode zur sicheren Ausschaltung eines thorakalen Aortenaneurysmas dar. Eine genaue Definierung von Einschlußkriterien sowie eine technische Weiterentwicklung der Stentprothesen sollte zu einer weiteren Verbesserung der klinischen Ergebnisse beitragen.SummaryBackground: The study was performed to check the validity of endovascular self-expandable stent-grafts in the treatment of descending thoracic aortic aneurysms. Methods: 17 patients, with an aneurysm of the descending thoracic aorta with a diameter of more than 6 cm, were treated with stent-grafts. The stent-graft-system was introduced via the femoral artery, the iliac artery or the abdominal aorta into the thoracic aorta and stent deployment was controlled by intraoperative angiography. Results: Successful placement was achieved in all cases. For aneurysmal exclusion 1 to 6 stents per patient were necessary (mean 2,8 stents). To ensure safe stent-graft-deployment, at first a subclavia to carotid artery transposition was performed in 8 patients. Vascular access was achieved through a small incision in the femoral arteries (n=6), iliac arteries (n=6) or abdominal aorta (n=5). 3 patients had stent-leaks, which were eliminated intraoperatively by re-stenting in the case of 2 patients. The intraoperative mortality rate was 0 %. Two patients (2/17=11,8%) died of an aneurysmal rupture or of acute ischaemia of the celiac axis followed by a multiple organ failure on the second or third day after operation. Conclusions: Insertion of endovascular stent-grafts is a promising and less invasive prodcedure in the treatment of thoracic aortic aneurysms. An exact definition of inclusion criteria as well as technical development of stent-grafts should contribute to further improvements of clinical results.

Cerebral Autosomal Dominant Arteriopathy (CADASIL) with cardiac involvement (ANOCA) and subcortical leukencephalopathy

We report a rare case of a CADASIL-syndrome with cardiac involvement presenting as ANOCA (angina in the absence of obstructive coronary artery disease). Our case highlights the added value of non-invasive fractional flow reserve (FFR)CT over coronary CT angiography (CTA), and recommends CTA as useful indication in CADASIL patients for screening of occult coronary artery disease (CAD).

Enhancement patterns in the fibro cellular tissue in different kinds of plaques of the internal carotid artery

BACKGROUND The differentiation between stable and vulnerable plaques in the internal carotid artery (ICA) remains a matter of interest. With the implementation of contrast agent in magnetic resonance imaging (MRI) a more detailed plaque characterization is possible. The study at hand focuses on enhancement patterns of fibro cellular tissue in different kinds of plaques in the ICA. METHODS Between May 2011 and December 2012, 49 patients (39 male) with >50% stenosis of the ICA were consecutively enrolled. In 10 patients with bilateral ICA stenosis, both plaques were included for analysis. We performed a classification of plaques according to Cai and observed 11 type 4-5 plaques, 15 type 6 plaques and 33 type 8 plaques. MRI was performed on a 3T whole body MR system. The standard 12 channel head coil was combined with the neck extension coil and two bilateral 7 cm loop coils. Post-contrast T1w images were subtracted from pre contrast images to identify late enhancement in fibro cellular tissue. Enhancement patterns were allocated as intraluminal, intraplaque and vasa vasorum enhancement in different types of plaques. RESULTS Fibro cellular tissue always exhibited a higher contrast enhancement compared to the sternocleidomastoid muscle. This reflects a higher grade of vascularization of the fibrocellular tissue. Contrast enhancement was present irrespective of the plaque type. In detail, intraluminal, intraplaque and vasa vasorum enhancement were observed in all types of plaques. Even type 8 plaques, according to the classification of Cai, had a significant contrast enhancement, though supposed to be with low inflammatory activity. CONCLUSION Type 8 plaques might not be as stable as postulated. Whether the relevant uptake of contrast agent is due to the fibrous tissue or reflects the inflammatory activity of the plaque should be matter of further investigations.