Residual Lumen Research Articles

In-Stent Restenosis in Peripheral Arterial Disease: Ultra-High-Resolution Photon-Counting Versus Third-Generation Dual-Source Energy-Integrating Detector CT Phantom Study in Seven Different Stent Types.

The visualization of peripheral in-stent restenosis using energy-integrating detector CT is challenging due to deficient spatial resolution and artifact formation. This study compares the first clinically available photon-counting detector CT to third-generation dual-source energy-integrating detector CT. Nylon cylinders with central bores (4mm, 2mm), mimicking 75% and 95% stenoses, were placed inside seven different 8-mm diameter stents and filled with diluted contrast medium. Phantoms were scanned with photon-counting detector CT at slice thicknesses of 0.2mm (available only in this scanner type), 0.5mm, and 1.0mm versus 0.5mm and 1.0mm in energy-integrating detector CT at matched CT dose indices. Contrast-to-noise ratios were calculated from attenuation rates. Residual lumen size was measured as full width at half-maximum. Subjective image quality was assessed by two independent blinded raters. Mean contrast-to-noise ratio was lowest in photon-counting detector CT at 0.2mm slice thickness (0%, 75%, and 95% in-stent restenosis: 6.11 ± 0.6, 5.27 ± 0.54, and 5.02 ± 0.66) and highest at 1.0mm slice thicknesses with similar measurements in photon-counting detector CT and energy-integrating detector CT (11.46 ± 1.08, 9.94 ± 1.01, 8.26 ± 1.0 vs. 3.34 ± 1.0, 9.92 ± 0.38, 7.94 ± 1.07). Mean full width at half-maximum measurements in photon-counting detector CT at 0.2mm slice thickness for 0%, 75%, and 95% in-stent restenosis were 8.00 ± 0.37, 3.98 ± 0.34, and 1.92 ± 0.16mm. Full width at half-maximum was least precise in 95% in-stent restenosis at 1.0mm slice thickness with similar measurements between scanners (1.57 ± 0.33 vs. 1.71 ± 0.15mm). Interrater correlation coefficient was 0.75 [95% CI: [0.53; 0.86]; subjective scores were best at 0.2mm slice thickness in photon-counting detector CT (19.43 ± 0.51 and 19.00 ± 0.68). In phantom in-stent restenosis in 8mm stents, we observed similar full width at half-maximum for photon-counting detector CT and energy-integrating detector CT in 0% and 75% in-stent restenosis, but at 95% in-stent restenosis, FWHM tended to be more accurate in smaller slice thicknesses in both scanners. Subjective image assessment yielded best results at 0.2mm slice thickness in photon-counting detector CT despite lower contrast-to-noise ratio.

Luminal shape and aortic remodelling after total arch replacement for type A aortic dissection: conventional and frozen elephant trunks.

This study was performed to assess postoperative aortic remodelling (AR) after total arch replacement (TAR) for acute type A aortic dissection (AAD) with a frozen elephant trunk (FET) or conventional elephant trunk (cET). Furthermore, the shape of the residual true lumen (TL) was analyzed based on elliptical Fourier analysis (EFA) and evaluated as a predictor of AR. This study involved patients who underwent TAR with a cET or FET for AAD from December 2006 to January 2023 at five institutions. AR was assessed at the levels of the 4th thoracic vertebra (Th4), Th7, Th10, and above the coeliac trunk. The shape of the residual TL at all four levels was analyzed based on EFA to calculate shape patterns as principal component (PC) values. Inverse probability of treatment weighting (IPTW) was performed for adjustment between the groups. In total, 180 patients (88 with cET and 92 with FET) were enrolled. The complete AR rate, defined as false lumen remodelling throughout the entire descending thoracic aorta, was significantly higher in the FET than cET group (63.4% vs 32.0%, P = 0.0013). The IPTW-adjusted Fine-Gray regression model revealed that the mean PC2 (hazard ratio, 0.22; P < 0.001) and PC3 (hazard ratio, 0.24; P = 0.009) of the four levels were independent predictors of complete AR. In AAD repair, the AR rate was significantly higher with use of the FET than cET. The shape patterns of the residual TL can be an important reference for predicting postoperative AR.

A case series of prenatal hepatic hilar cyst in the presence of a gallbladder - navigating the dilemma between biliary atresia and choledochal cyst

BackgroundPrenatally diagnosed hepatic hilar cysts are a challenging finding for the clinician. They can either be a sign of cystic biliary atresia (BA) or a choledochal cyst (CC), two diagnoses with different postnatal management and prognosis. Based on a case report of four patients, we aim to propose a management algorithm for prenatally diagnosed “hepatic hilar cysts”.Case presentationA hepatic hilar cyst, ranging from 5 to 25 mm, was detected prenatally in all four girls confirmed postnatally along with the presence of a gallbladder. Stool color was normal until two weeks of life at which time the stool color became lighter, and the patients developed cholestasis. All were operated before seven weeks of life: Case 1 had a CC with patent but irregular intrahepatic bile ducts at intraoperative cholangiogram, and no communication with the duodenum. A Roux-en-Y bilioenteric anastomosis was performed. The cyst showed complete epithelial lining loss, and liver pathology showed BA features. Case 2 had the final diagnosis of cystic BA with patent but abnormal intrahepatic bile ducts. She underwent two operations: the first operation at four weeks as described for case 1, since intraoperative findings were similar, as was histology. As cholestasis increased postoperatively, she underwent a Kasai hepato-porto-enterostomy six weeks later, where distinct BA findings were found with complete scarring of the hilar plate. Case 3 had a cystic BA with the cyst located within the common bile duct and atretic bile ducts proximal to the porta hepatis. It exhibited no communication with the liver or duodenum. A Kasai operation was performed, with histology showing complete epithelial loss within the cyst wall and scarring of the hilar plate. Case 4 had a cystic BA presenting a completely obliterated hepatic duct with the cyst lying within the common bile duct. A Kasai procedure was performed. Histology showed a common bile duct with a residual lumen of 0.1 mm.ConclusionsThe spectrum of disease from CC to BA in the setting of a prenatally discovered hepatic hilar cyst is emphasized. Even if cholangiogram differentiates most patients with BA from those with CC, caution is advised for transitional types.

Dual-source photon-counting computed tomography for coronary in-stent observation: influence of heart rate and virtual monoenergetic image.

To investigate the effect of heart rate and virtual monoenergetic image (VMI) on coronary stent imaging in dual-source photon-counting detector computed tomography (PCD-CT). A dynamic cardiac phantom was used to vary the heart rate at 50 beats per minute (bpm), 70bpm, and 90bpm. Five types of stents (4.0mm, 3.5mm, 3.0mm, 2.75mm, and 2.5mm diameter) were scanned at three different locations and reconstructed VMI at 70keV. In addition, 50% stenosis was assessed for 3.0mm and 4.0mm stents. To assess in-stent stenosis, 40keV, 70keV, and 100keV images were compared. Measurable lumen and contrast to noise ratio (CNR) from lumen to stenosis were evaluated quantitatively. A-4-point scale was used for the qualitative image quality of in-stent stenosis. The measurable lumen had no significant differences among heart rates in patent stents (p = 0.55). In-stent stenosis, the residual lumen was significantly larger in 40keV [27.5% (20.8-32.3%)] than in 70keV [11.5% (10.0-23.0%), p < 0.05] and 100keV [0% (0-5.2%), p < 0.05]. The CNR was higher in 40keV [12.5 (7.5-18.2)] than in 70keV [5.3 (2.9-7.7), p < 0.05] and 100keV [1.3 (0.5-2.7), p < 0.05]. The image quality was better in 40keV (3.4 ± 0.7) than in 70keV [(2.6 ± 0.8), p < 0.05] and 100keV [(1.3 ± 0.4), p < 0.05]. Dual-source PCD-CT maintains a measurable lumen even at high heart rates. Adjusting the VMI can be helpful in visualizing the in-stent stenosis.

Aggressive Treatment Strategy at Index Thoracic Endovascular Aortic Surgery is Associated with Reduced Need for Short-Term Reintervention in Patients with Aortic Dissection

Thoracic endovascular aortic surgery (TEVAR) is the modern standard of treatment for patients with Type B aortic dissection, however it is unclear how the initial length of treated aorta affects long-term outcomes. This study aims to elucidate risk factors for secondary intervention after TEVAR for aortic dissection, focusing on length of aortic treatment at index operation. A retrospective multihospital chart review was completed for patients treated between 2011 and 2022 who underwent TEVAR for aortic dissection with at least 1year of post-TEVAR imaging and follow-up. Patient demographics and characteristics were analyzed. In this study, aortic zones treated only included those managed with a covered stent graft. The primary outcome measure was any need for secondary intervention. A total of 151 patients were identified. Demographics included a mean age of 57years, with 31.8% of the patients being female. Forty-three patients (28.5%) underwent secondary intervention after TEVAR, with a mean follow-up of 1.6years. The most common indication for secondary intervention was aneurysmal degeneration of the residual false lumen (76%). There was a significant difference in the number of aortic zones treated in patients who did and did not require secondary intervention (2.3 ± 1 vs. 2.7 ± 1, P=0.04). Additionally, patients with 3 or more aortic zones of treatment had a significant difference in the need for reintervention (32% secondary intervention versus 52% no secondary intervention, P=0.02). At least 3 zones of aortic treatment at index TEVAR is associated with a decreased need for overall reintervention. Modern treatment of acute and subacute type B dissection should stress an aggressive initial repair, balanced by the potential increased risk of spinal cord ischemia.

Is TEVAR an Effective Approach to Prevent Complications after Surgery for Aortic Dissection Type A? A Systematic Review.

Introduction: A residual false lumen after treatment for Aortic Dissection type A (AD) has been associated with early complications, such as A malperfusion or rupture and mid-term or delayed complications, such as aneurysm formation or dissection expansion. Thoracic Endovascular Aortic Repair (TEVAR) is considered an effective solution by several surgical teams to prevent future complications. In this systematic review, all published data regarding the implementation of TEVAR after previous treatment for AD were collected in order to investigate indications, methods, clinical outcomes and aortic remodeling in these patients. Methods: The aim of this study was to investigate the indications, the methods and the efficacy of TEVAR usage after surgical treatment of AD. Data for this study were collected from four widely used medical databases (MEDLINE, SCIENCE DIRECT, GOOGLE SCHOLAR, OVID). All the results for each database were recorded and were analyzed with a systematic method. Techniques and clinical outcomes were investigated. Aortic remodeling was evaluated based on the following parameters in these studies: aortic diameter, true lumen diameter, false lumen diameter, false lumen thrombosis and false lumen patency. Results: The results obtained from the search among all databases comprised 1410 articles and of these articles 9 were included in the review. The majority of the studies were retrospective (seven out of nine studies), while no study was randomized. The total number of patients was 157 and 133 of them (84.7% of patients) were treated with TEVAR in zone 3 without extension below the diaphragm intraoperatively. Among 142 patients, the calculated mortality rate was 12.7% (18 of 142 patients), with 2.8% (4 of 142 patients) presenting with stroke. The percentage of patients with total or partial thrombosis combined was 65.9% (62 patients in a population of 92). The reintervention rate was 18.7%. Conclusions: TEVAR after AD surgery is an approach usually chosen in clinical practice, but the criteria of its usage are uncertain. This method is safe and enhances aortic remodeling with an acceptable reintervention rate. Definite guidelines in this field should be created in order to delineate whether TEVAR after AD surgery is beneficial as a preventive measure to aorta-related complications and to decide under which criteria this approach should be chosen.

Evaluation of long-term outcomes of percutaneous coronary intervention in patients with moderate to severe calcified coronary artery lesions.

Coronary artery calcification reduces elasticity and can cause hemodynamic disturbances, increasing the risk of cardiovascular complications. Furthermore, coronary calcifications make cardiovascular interventions difficult. The present study aimed to study the cardiovascular outcomes of the coronary intervention of calcified lesions in the Iranian population. The present cross-sectional study evaluated patients with moderate to severe calcified coronary artery lesions on angiography who were candidates for percutaneous coronary intervention (PCI). Demographic, echocardiographic, and angiographic data of the patients were recorded. In addition, clinical outcomes, including mortality, myocardial infarction, stroke, and stent thrombosis, were also measured 1 year after the procedure. A total of 125 participants (65% male and 35% female) with a median age of 69 (13.0) years old were enrolled. The most common calcification degree was 270° (43.5%), followed by 360° (35.5%) and 180° (21.0%). Most patients had thrombolysis in myocardial infarction (TIMI) score of 3 (47.6%). A more than 10% residual coronary minimum lumen diameter was seen in 25.8% of patients. Puncture site hemorrhage and contrast-induced nephropathy were observed in 2 (1.6%) and 1 (0.8%) patients, respectively. Following 1 year after PCI, no cases of mortality, cerebrovascular accident, myocardial infarction, and stent thrombosis were reported. Furthermore, we observed one case of heart failure (0.8%) and target lesion revascularization (0.8%). In addition, we revealed a significant relationship between calcification degree and TIMI (p < 0.001) and body mass index (p = 0.049). Percutaneous management of calcified lesions with noncompliant balloon and one or two guidewires was associated with a good success rate and few complications.

A case of stent-assisted balloon-induced intimal disruption and relamination of distal remaining aortic dissection after the ascending aorta and aortic arch replacement for acute aortic dissection

BackgroundThe early survival rate of patients with acute type A aortic dissection (TAAD) has improved remarkably over the past two decades. However, a false lumen may remain after proximal aortic repair and is a potential risk factor for aortic diameter enlargement, aortic rupture, and death in the chronic phase. In the stent-assisted balloon-induced intimal disruption and relamination of aortic dissection (STABILISE) technique, a stent graft is implanted at the proximal part of the aortic dissection, followed by bare-metal aortic stent placement over the distal aortic dissection. Next, an aortic balloon catheter is dilated inside the stent graft and the bare stent to disrupt the intima and collapse the false lumen, immediately restoring uniluminal thoracoabdominal aortic flow. This report describes our experience with the STABILISE technique for a residual aortic dissection after an ascending aorta, and partial aortic arch replacement for acute TAAD resulted in complications.Case presentationA 60-year-old man presented to our hospital with chest pain, paresthesia, and left lower-limb paralysis. He was diagnosed with acute type A aortic dissection (TAAD) and malperfusion of the left lower limb by computed tomography (CT), and an emergent ascending aorta and partial aortic arch replacement were performed. Immediately after surgery, the left femoral arterial pulse improved, and left lower limb revascularization was deferred. The postoperative course was good; however, back pain and intermittent claudication recurred on the 9th day after surgery. A CT examination revealed persistent antegrade false lumen flow in the descending thoracic aorta through the left subclavian artery dissection and retrograde false lumen flow from the thoracoabdominal segment, resulting in aortic diameter enlargement and narrowing of the true lumen. The symptoms did not improve, and the STABILISE technique was performed on the 12th day after the initial aortic surgery. The patient’s subsequent course was good; the back pain and intermittent claudication resolved. The patient was discharged on the 8th day after the STABILISE technique.ConclusionsThe STABILISE technique can obliterate the false lumen and resolve symptoms associated with a residual false lumen after proximal aortic repair for acute TAAD.

Comparative Study of the Diagnostic Value of Zero-Echo-Time Magnetic Resonance Angiography With Time-of-Flight Magnetic Resonance Angiography for Intracranial Aneurysm.

Intracranial aneurysm (IAN) is a class of cerebrovascular diseases with a serious threat to patients, and an accurate diagnosis of IAN is very important for both selection of the appropriate therapy and prediction of the prognosis. This study aimed to evaluate the diagnostic values of zero-echo-time magnetic resonance angiography (ZTE-MRA) and time-of-flight magnetic resonance angiography (TOF-MRA) in patients with IAN. Digital subtraction angiography, ZTE-MRA, and TOF-MRA were performed in 18 patients diagnosed with IAN. The images of ZTE-MRA and TOF-MRA were compared for image quality, qualitative diagnosis, detailed diagnosis, number of thrombi, and residual aneurysm lumen, with digital subtraction angiography as the reference. Zero-echo-time MRA and TOF-MRA did not show a significant difference in image quality or detailed information (including aneurysm size, growth direction, and angle with the aneurysm-carrying vessel) ( P > 0.05). However, ZTE-MRA showed advantages over TOF-MRA in terms of qualitative diagnosis (sensitivity and specificity), intra-aneurismal thrombus detection, and residual aneurysm lumen detection after embolization ( P < 0.05). Compared with TOF-MRA, ZTE-MRA showed greater diagnostic value for IAN patients in terms of qualitative diagnosis, as well as the detection of intra-aneurysm thrombi and residual aneurysm lumen after embolization.

Multidisciplinary treatment of benign tracheal stenosis—a case report

Video 1 Pre-operative bronchoscopic control that showed a sub-total tracheal stenosis above tracheal cannula, with a residual tracheal lumen of 1–2 mm, at a distance of 2.5 cm from vocal cords.

Distal Stent Graft-Induced New Entry After Frozen Elephant Trunk Procedure for Aortic Dissection

The purpose of this study was to evaluate the risk factors of distal stent graft-induced new entry (dSINE) after frozen elephant trunk (FET) procedure for aortic dissection (AD) and to consider strategies to prevent this complication. This retrospective review included 52 patients who had undergone aortic arch repair for AD with the FET procedure using J Graft FROZENIX from 2014 to 2020 at a single center. Baseline characteristics, aortic characteristics and mid-term outcomes were compared between patients with and without dSINE. The extent of unfolding of the device and movement of the distal edge of the device were analyzed by multidetector computed tomography. The primary endpoints were survival and freedom from reintervention. dSINE was the most prevalent complication after FET procedure, with an incidence of 23%. Eleven of 12 patients with dSINE underwent secondary interventions. dSINE was common in chronic aortic dissection (P=0.001) and was associated with the residual false lumen area (P<0.001) and movement distance of the distal edge of the device in the cranial direction (P<0.001). The distal edge of the FET is more likely to move in the cranial direction, and this movement may cause dSINE.

Pre-operative bronchoscopic control that showed a sub-total tracheal stenosis above tracheal cannula, with a residual tracheal lumen of 1–2 mm, at a distance of 2.5 cm from vocal cords.

Pre-operative bronchoscopic control that showed a sub-total tracheal stenosis above tracheal cannula, with a residual tracheal lumen of 1–2 mm, at a distance of 2.5 cm from vocal cords.

Outcomes of Percutaneous Coronary Interventions for Long Diffuse Coronary Artery Disease with Extremely Small Diameter

The optimal percutaneous coronary intervention (PCI) strategy and clinical outcomes of long lesions with an extremely small residual lumen remain unclear. This study aimed to assess the efficacy of a modified stenting strategy for diffuse coronary artery disease (CAD) with an extremely small distal residual lumen. 736 Patients who received PCI using second-generation drug-eluting stents (DES) ≥38 mm long were retrospectively included and categorized into an extremely small distal vessel (ESDV) group (≤2.0 mm) and a non-ESDV group (>2.0 mm) according to the maximal luminal diameter of the distal vessel (dsDMax). A modified stenting technique was applied by landing an oversized DES in the distal segment with the largest luminal diameter and maintaining the distal stent edge partially expanded. The mean dsDMax and stent lengths were 1.7 ± 0.3 mm and 62.6 ± 18.1 mm in the ESDV group and 2.7 ± 0.5 mm and 59.1 ± 16.0 mm in non-ESDV groups, respectively. The acute procedural success rate was high in both the ESDV and non-ESDV groups (95.8% and 96.5%, p = 0.70) with rare distal dissection (0.3% and 0.5%, p = 1.00). The target vessel failure (TVF) rate was 16.3% in the ESDV group and 12.1% in the non-ESDV group at a median follow-up of 65 months without significant differences after propensity score matching. PCI using contemporary DES with this modified stenting technique is effective and safe for diffuse CAD with extremely small distal vessels.

Aortic shape variation after frozen elephant trunk procedure predicts aortic events: Principal component analysis study

ObjectiveThe frozen elephant trunk procedure is a well-established technique for the repair of type A ascending aortic dissection and complex aortic arch pathology. The ultimate shape created by the repair may have consequences in long-term complications. The purpose of this study was to apply a machine learning technique to comprehensively describe 3-dimensional aortic shape variations after the frozen elephant trunk procedure and associate these variations with aortic events. MethodsComputed tomography angiography acquired before discharge of patients (n = 93) who underwent the frozen elephant trunk procedure for type A ascending aortic dissection or ascending aortic arch aneurysm was preprocessed to yield patient-specific aortic models and centerlines. Aortic centerlines were subjected to principal component analysis to describe principal components and aortic shape modulators. Patient-specific shape scores were correlated with outcomes defined by composite aortic event, including aortic rupture, aortic root dissection or pseudoaneurysm, new type B dissection, new thoracic or thoracoabdominal pathologies, residual descending aortic dissection with residual false lumen flow, or thoracic endovascular aortic repair complications. ResultsThe first 3 principal components accounted for 36.4%, 26.4%, and 11.6% of aortic shape variance, respectively, and cumulatively for 74.5% of the total shape variation in all patients. The first principal component described variation in arch height-to-length ratio, the second principal component described angle at the isthmus, and the third principal component described variation in anterior-to-posterior arch tilt. Twenty-one aortic events (22.6%) were encountered. The degree of aortic angle at the isthmus described by the second principal component was associated with aortic events in logistic regression (hazard ratio, 0.98; 95% confidence interval, 0.97-0.99; P = .046). ConclusionsThe second principal component, describing angulation at the region of the aortic isthmus, was associated with adverse aortic events. Observed shape variation should be evaluated in the context of aortic biomechanical properties and flow hemodynamics.

Reply from authors: Adjunctive endovascular options for chronic type B aortic dissection.

Thoracic endovascular aortic repair (TEVAR) has been increasingly offered in patients with chronic type B aortic dissection (cTBAD). However, the most notable obstacle to achieving positive aortic remodeling is the presence of a thick aortic septum, which prevents elimination of the false lumen flow despite entry tear coverage. Therefore, the absolute benefit of TEVAR remains undefined. Historically, efforts have been devoted to endovascularly eliminating residual false lumen flow, primarily focusing on 2 approaches: one is obliteration of the false lumen using embolization techniques, and the other is creation of a single aortic lumen as optimized landing zones.

ODP305 Differentiation Potential of Marginal Layer-Derived Adult Pituitary Stem/Progenitor Cells into Vascular Endothelial Cells and Pericytes in Mice

Abstract The anterior lobe (AL) of the pituitary gland consists five types of hormone-producing cells and fenestrated sinusoids (i. e., vascular endothelial cells and pericytes) that cooperate to maintain the physiological function of the gland. In addition, the population of cells located in pituitary stem/ progenitor cell niche, the marginal layer, which faces the residual lumen of the Rathke's pouch, serve to renew pituitary cells throughout life. We recently established a protocol for isolating marginal layer-derived adult pituitary stem/progenitor cells (MPSCs) by using differences in cell adhesion (1), and then showed differentiation potential into hormone-producing cells by subjecting MPSCs to three-dimensional culture. However, it is unclear whether MPSCs are capable of differentiating into all types of cells that constitute the pituitary gland. In this study, we performed DNA microarray analysis in MPSCs, which were proliferated by two-dimensional (2D) culture, for studying comprehensively gene expression profiles. Next, we investigated what kind of cells MPSCs would differentiate into. Comparing gene expression profiles of the AL and MPSCs, in MPSCs, 1776 genes were increased more than 4-fold and 1715 genes were decreased 4-fold compared to the AL (p&amp;lt;0. 05, respectively). The upregulated genes included pituitary stem/progenitor cell markers (ex. Sox2, Sox9, Klf4, Prrx1), niche markers (ex. Cdh1, Krt8), and cell surface antigens (ex. Cd9, Cd34, Cd44). On the other hand, most of the downregulated genes were differentiation markers (ex. Pou1f1, Gata2, Tbx19, Kdr). Next, immunofluorescent analysis revealed that most of the MPSCs were positive for CD34, the hematopoietic stem cell marker. After further 2D culture of MPSCs for 5-7days, vascular endothelial marker PECAM1-positive cells were detected by immunofluorescent analysis, but pericyte marker CSPG4-positive cell not. When TGFβ was applied to 2D culture of MPSCs, CSPG4-positive cells were detected instead of PECAM1-positive cells. Expression levels of Pecam1and Cspg4 were also examined by qPCR analysis, which corresponded to the results of immunofluorescent analysis. On the other hand, expression levels of anterior hormone genes were almost unchanged. These results have demonstrated that MPSCs could differentiate into vascular endothelial cells and pericytes. The present study suggests that pituitary stem/progenitor cells, which derived from the marginal layer, are a source of not only hormone-producing cells but also cells that constitute blood vessels. Reference: (1) Shintani and Higuchi, Stem Cell Res. 2021 Feb 2;52: 102223. Presentation: No date and time listed

Concomitant distal bare-metal stenting for residual true lumen stenosis in a frozen elephant trunk technique for acute type A aortic dissection.

For acute type A aortic dissection (TAAD), we have performed aortic arch repair using a frozen elephant trunk (FET) since 20141 and observed that aortic remodeling was limited at the level below the FET stent end postoperatively.2 For acute type B aortic dissection (TBAD), the PETTICOAT (provisional extension to induce complete attachment) technique has been an option to reopen the residual true lumen (TL) collapse after thoracic endovascular aortic repair (TEVAR).3 Similarly, proximal stent grafting with distal bare-metal stenting in a 2-staged manner has been reported in repair of acute DeBakey type I aortic dissection.

High-resolution magnetic resonance vessel wall imaging-guided endovascular recanalization for nonacute intracranial artery occlusion.

On the basis of the characteristics of occluded segments on high-resolution magnetic resonance vessel wall imaging (MR-VWI), the authors evaluated the role of high-resolution MR-VWI-guided endovascular recanalization for patients with symptomatic nonacute intracranial artery occlusion (ICAO). Consecutive patients with symptomatic nonacute ICAO that was refractory to aggressive medical treatment were prospectively enrolled and underwent endovascular recanalization. High-resolution MR-VWI was performed before the recanalization intervention. The characteristics of the occluded segments on MR-VWI, including signal intensity, occlusion morphology, occlusion angle, and occlusion length, were evaluated. Technical success was defined as arterial recanalization with modified Thrombolysis in Cerebral Infarction grade 2b or 3 and residual stenosis < 50%. Perioperative complications were recorded. The characteristics of the occluded segments on MR-VWI were compared between the recanalized group and the failure group. Twenty-five patients with symptomatic nonacute ICAO that was refractory to aggressive medical treatment were consecutively enrolled from April 2020 to February 2021. Technical success was achieved in 19 patients (76.0%). One patient (4.0%) had a nondisabling ischemic stroke during the perioperative period. Multivariable logistic analysis showed that successful recanalization of nonacute ICAO was associated with occlusion with residual lumen (OR 0.057, 95% CI 0.004-0.735, p = 0.028) and shorter occlusion length (OR 0.853, 95% CI 0.737-0.989, p = 0.035). The high-resolution MR-VWI modality could be used to guide endovascular recanalization for nonacute ICAO. Occlusion with residual lumen and shorter occlusion length on high-resolution MR-VWI were identified as predictors of technical success of endovascular recanalization for nonacute ICAO.

To Explore the Effect of Preoperative Hemodynamic Factors on The Outcome of Pseudolumen After Stanford Type B Aortic Dissection TEVAR Based on Computer Fluid Dynamics.

The preoperative aortic hemodynamic data of patients with Stanford type B aortic dissection were obtained by computer fluid dynamics (CFD). Then we explored the relationship between hemodynamic data and short-term residual pseudolumen after thoracic endovascular aortic repair (TEVAR) and predict the latter through the former. We collected the relevant data of 53 patients who underwent TEVAR in our hospital. They were divided into the A group (residual false lumen group) and B group (closed false lumen group), according to whether there was a residual false cavity around the stent recently after TEVAR. Three-dimensional reconstruction and CFD analysis of the thoracic and abdominal aorta was performed by DSCTA before the operation to obtain the aortic wall shear stress (WSS) and maximum blood flow velocity of the true and false lumen at the entrance, middle point of the long axis, and distal decompression port at the peak time of ventricular systolic velocity. Through the statistical analysis, we further studied the predictive value of hemodynamic data for residual pseudolumen. There was no significant difference in age, male, preoperative and postoperative thoracic and abdominal aorta DSCTA interval, history of hypertension, history of diabetes, smoking, Pt and APTT at admission between the two groups (P > 0.05). The blood flow velocity and shear stress at the entrance of the false lumen and the distal decompression port in the two groups were statistically significant (P < 0.05), while the other hemodynamic indexes were not statistically significant (P > 0.05). Binary logistic regression analysis further showed that the shear stress of the false lumen at the level of the distal decompression port (OR = 1.73, P = 0.01) was an independent risk factor for the residual false lumen around the stent in the early stage after TEVAR. The ROC curve analysis showed that the AUC area of the ROC curve corresponding to the shear stress of the false cavity at the level of the distal decompression port was 0.83, the best cross-sectional value was 9.49pa, and the sensitivity and specificity were 84.60% and 72.50%. The residual pseudolumen after TEVAR is related to the hemodynamic factors in the aorta before TEVAR. Preoperative hemodynamic data also have good predictive value. When the shear stress of the false lumen at the level of the distal decompression port is greater than 9.49pa, the probability of residual false lumen around the stent during the perioperative period significantly increases.

Clinical characteristics and misdiagnosis of spontaneous isolated superior mesenteric artery dissection

BackgroundSpontaneous isolated superior mesenteric artery (SMA) dissection (SISMAD) is a rare disease with a potentially fatal pathology. Due to the lack of specificity of clinical characteristics and laboratory tests, misdiagnosis and missed diagnosis are often reported. Therefore, the aim of this study was to investigate the clinical characteristics and misdiagnosis of SISMAD.MethodsIn a registry study from January 2013 to December 2020, 110 patients with SISMAD admitted to the First Affiliated Hospital of Wenzhou Medical University were enrolled. Descriptive methods were used to analyse clinical characteristics, laboratory data, diagnostic method or proof, misdiagnosed cases, plain computed tomography (CT) findings and dissection features. To study the relationship between dissection features and treatment modality, the selected patients were classified into the conservative group (n = 71) and the non-conservative group (n = 39). The Chi-square test and Student’s t-test were used to compare the conservative and non-conservative groups.ResultsOne hundred ten patients with SISMAD, including 100 (90.9%) males and 10 (9.1%) females, with a mean age of 52.4 ± 7.6 years, were enrolled in the study. Relevant associated comorbidities included a history of hypertension in 43 cases (39.1%), smoking in 46 cases (41.8%), and alcohol consumption in 34 cases (30.9%). One hundred four patients (94.5%) presented with abdominal pain. Abnormalities in the C-reactive protein lever, white blood cells count and D-dimer lever were the 3 most common abnormal findings. There were 32 misdiagnosis or missed diagnosis. Fourteen cases were misdiagnosed because of insufficient awareness. Twelve cases were misdiagnosed because of disease features. Twenty cases were misdiagnosed as SMA embolism. Among them, There were 15 cases of Yun type IIb SISMAD. Sixty-six patients underwent plain CT. The maximum SMA diameter was 12.1 (11.3–13.1) mm, and the maximum SMA diameter was located on the left renal vein (LRV) plane in 68.2% of cases. Dissection features observed on contrast-enhanced CT (CECT), CT angiography (CTA), or digital subtraction angiography (DSA) showed that there were 70 cases (63.6%) of Yun type IIb SISMAD, the maximum SMA diameter was 13.0 ± 2.4 mm, the location of the maximum SMA diameter was on the LRV plane in 64.5% of cases, and 7.3% of cases were complicated with intestinal obstruction, including bowel necrosis in 3.6% of cases. There were differences between the conservative group and non-conservative groups in the residual true lumen diameter or degree of true lumen stenosis and the presence of intestinal obstruction or bowel necrosis (all P < 0.05).ConclusionFor SISMAD, misdiagnosis and missed diagnosis were usually caused by insufficient awareness and disease features. SISMAD should be considered in the differential diagnosis of patients presenting with unexplained abdominal pain, especially males, patients in the 5th decade of life, patients with hypertension, and patients with an enlarged SMA diameter or a maximum SMA diameter located on the LRV plane on plain CT. Mesenteric CTA or CECT should be recommended for the investigation of these conditions.