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41.

Objective

To compare perioperative and long-term outcomes in patients undergoing hemiarch and aggressive arch replacement for acute type A aortic dissection (ATAAD).

Methods

From 1996 to 2017, we compared outcomes of hemiarch (n = 322) versus aggressive arch replacements (zones 2 and 3 arch replacement with implantation of 2-4 arch branches, n = 150) in ATAAD. Indications for aggressive arch were arch aneurysm >4 cm or intimal tear in the aortic arch that was not resectable by hemiarch replacement, or dissection of arch branches with malperfusion.

Results

Patients in the aggressive arch group were significantly younger (mean age: 57 vs 61 years old) and had significantly longer hypothermic circulatory arrest, cardiopulmonary bypass, and aortic crossclamp times. There were no significant differences in perioperative outcomes between hemiarch and aggressive arch groups, including 30-day mortality (5.3% vs 7.3%, P = .38) and postoperative stroke rate (7% vs 7%, P = .96). Over 15 years, Kaplan–Meier survival was similar between hemiarch and aggressive arch groups (log-rank P = .55, 10-year survival 70% vs 72%). Given death as a competing factor, incidence rates of reoperation over 15 years (2.1% vs 2.0% per year, P = 1) and 10-year cumulative incidence of reoperation (14% vs 12%, P = .89) for arch and distal aorta pathology were similar between the 2 groups.

Conclusions

Both hemiarch and aggressive arch replacement are appropriate approaches for select patients with ATAAD. Aggressive arch replacement should be considered for an arch aneurysm >4 cm or an intimal tear at the arch unable to be resected by hemiarch replacement, or dissection of the arch branches with malperfusion.  相似文献   
42.
43.

Background

Pulmonary hypertension (PH) is a comorbidity associated with interstitial lung disease (ILD). The purpose of this study was to evaluate the influence of PH on intrahospital mortality in lung transplantation (LT) for ILD.

Methods

We conducted a retrospective cohort study of 66 patients who underwent LT for ILD at the 12 de Octubre University Hospital (Madrid, Spain) from October 2008 to June 2014. PH was defined as mean pulmonary arterial pressure (mPAP) ≥25 mmHg on right-sided heart catheterization and intrahospital mortality as any death taken place after the transplantation of patients not being discharged.

Results

We retrospectively analyzed data of 66 patients; they were stratified by the presence or absence of PH before LT. Twenty-seven patients (41%) had PH. The PH group had a lower diffusing capacity of carbon monoxide (DLCO), carbon monoxide transfer coefficient (KCO), and 6-minute walk distance test (6MWT) and a higher total lung capacity (TLC), modified medical research council dyspnea scale (mMRC), and lung allocation score (LAS) than the non-PH group. Patients with PH more often underwent double lung transplantation (DLT; 59%) than single lung transplantation (SLT).Intrahospital mortality was 13% (9/66). No significant differences were observed in Kaplan-Meier survival curves for the PH and non-PH groups with a median survival time of 46 days versus 33 days (IQR 26–74; log-rank P = .056); however, the postoperative length of stay in the hospital was greater in the PH group.

Conclusions

In our cohort, pulmonary hypertension was not related to early mortality in lung transplantation recipients for interstitial lung diseases.  相似文献   
44.

Background and purpose

The vein of Galen aneurysmal malformation (VGAM) is a rare congenital vascular malformation with a higher morbidity and mortality, especially in neonates. Ultrasound, CT and MR are usually used in diagnosis and treatment monitoring of these disorders. In this current study, we aim to examine utility of SWI in evaluation of treatment response in infants with VGAM.

Materials and methods

We performed a retrospective chart analysis of children with VGAM in our institution between January 2008 and December 2016. Inclusion criteria included; confirmed VGAM on DSA; available SWI sequence at baseline and at follow up after at least a single embolization session; age at initial MR of 18?years or younger. Signal intensity and Angioarchitecture of VGAM and cerebral veins on SWI, as well as hydrocephalus and clinical outcome were evaluated.

Results

Of 11 patients identified with VGAM in our institution, 5 children (3 males and 2 females) satisfied the inclusion criteria. The average age at initial MR was 29?days (range 1–120). Fourteen MRI were available for review. All children had VGAM of mural type. Intramedullary veins were dilated and SWI-hypointense in all children, while subependymal and sulcal veins were dilated and SWI-hypointense in 4 patients on initial MRI. On the first available follow up MRI, cerebral veins have mostly normalized in 4 children and remained mostly dilated and SWI-hypointense in 1 child; even after complete treatment of the VGAM.

Conclusion

Our preliminary findings show that SWI seems to offer a beneficial non-invasive tool in evaluating passive venous congestion patterns in pediatric patients with VGAM. It remains to be determined in larger studies, the clinical significance of these SWI changes.  相似文献   
45.
46.

Statement of problem

Polymeric material for 3-dimensional printing can be used to fabricate occlusal devices. However, information about fracture resistance and wear is scarce.

Purpose

The purpose of this in vitro study was to investigate the fracture resistance and 2-body wear of 3-dimensional–printed (3DP) (FotoDent splint; Dreve Dentamid GmbH), milled polymethylmethacrylate (CAM) (Temp Basic; Transpa 95H16, Zirkonzahn GmbH), and conventionally fabricated polymethylmethacrylate (CAST) (Castdon; Dreve Dentamid GmbH) occlusal devices.

Material and Methods

A total of 96 occlusal devices were prepared according to the 3 different manufacturing techniques 3DP, CAM, and CAST (n=32). For each manufacturing technique, specimens were further divided into initial fracture resistance tests (n=16) and artificial aging in the mastication simulator (50 N, 37°C) with 2-body wear followed by fracture resistance tests (n=16). The fracture resistance was determined using a universal testing machine (1 mm/min). The wear was measured after 20?000 and 120?000 mastication cycles with the replica technique, mapped with a laser scanner, and quantified in R software. Data were analyzed using a 2-way ANOVA followed by a 1-way ANOVA with Scheffé or Games-Howell post hoc tests, repeated measures ANOVA with corrected Greenhouse-Geisser P values, and the Levene, Mann-Whitney, and paired t tests (α=.05).

Results

CAM presented higher initial fracture resistance than 3DP or CAST (P<.001). After mastication simulation, CAM followed by 3DP showed higher fracture resistance than CAST (P<.001). Mastication simulation decreased the fracture resistance for CAM and CAST (P<.001) but not for 3DP (P=.78). Three-dimensional–printed occlusal devices showed the highest material volume loss, followed by CAM and the lowest in CAST (P<.001).

Conclusions

Three-dimensional–printed occlusal devices showed lower wear resistance and lower fracture resistance than those milled or conventionally fabricated. Therefore, only short-term application in the mouth is recommended. Further developments of occlusal device material for 3-dimensional printing are necessary.  相似文献   
47.

Background

Endovascular aneurysm sealing (EVAS) represents a novel approach to the treatment of abdominal aortic aneurysms. It uses polymer technology to achieve an anatomic seal within the sac of the aneurysm. This cohort study reports the early clinical outcomes, technical refinements, and learning curve during the initial EVAS experience at a single institution.

Methods

Results from 150 consecutive EVAS cases for intact, infrarenal abdominal aortic aneurysms are reported here. These cases were undertaken between March 2013 and July 2015. Preoperative, perioperative, and postoperative data were collected for each patient prospectively.

Results

The median age of the cohort was 76.6 years (interquartile range, 70.2-80.9 years), and 87.3% were male. Median aneurysm diameter was 62.0 mm (IQR, 58.0-69.0 mm). Adverse neck morphology was seen in 69 (46.0%) patients, including aneurysm neck length <10 mm (17.3%), neck diameter >32 mm or <18 mm (8.7%), and neck angulation >60 degrees (15.3%). Median follow-up was 687 days (IQR, 463-897 days); 37 patients (24.7%) underwent reintervention. The rates of unresolved endoleak are 1.3% type IA, 0.7% type IB, and 2.7% type I. There were no type III endoleaks. There have been seven secondary ruptures in this cohort; all but one of these patients survived after reintervention. Only one rupture occurred in an aneurysm that had been treated within the manufacturer's instructions for use (IFU).

Conclusions

The rate of unresolved endoleaks is satisfactorily low. The incidence of secondary rupture is of concern; however, when the IFU are adhered to, the rate is very low. The results of this study suggest that working within the IFU yields better clinical results.  相似文献   
48.
49.

Background

Multiparametric magnetic resonance imaging (mpMRI) undoubtedly affects the diagnosis and treatment of localized prostate cancer (CaP). However, clinicians need a better understanding of its accuracy and limitations in detecting individual CaP foci to optimize management.

Objective

To determine the per-lesion detection rate for CaP foci by mpMRI and identify predictors of tumor detection.

Design, setting, and participants

We carried out a retrospective analysis of a prospectively managed database correlating lesion-specific results from mpMRI co-registered with whole-mount pathology (WMP) prostatectomy specimens from June 2010 to February 2018. Participants include 588 consecutive patients with biopsy-proven CaP undergoing 3-T mpMRI before radical prostatectomy at a single tertiary institution.

Outcome measurements and statistical analysis

We measured mpMRI sensitivity in detecting individual CaP and clinically significant (any Gleason score ≥7) CaP foci and predictors of tumor detection using multivariate analysis.

Results and limitations

The final analysis included 1213 pathologically confirmed tumor foci in 588 patients with primarily intermediate- (75%) or high-risk (12%) CaP. mpMRI detected 45% of all lesions (95% confidence interval [CI] 42–47%), including 65% of clinically significant lesions (95% CI 61–69%) and nearly 80% of high-grade tumors. Some 74% and 31% of missed solitary and multifocal tumors, respectively, were clinically significant. The majority of missed lesions were small (61.1% ≤1 cm); 28.3% were between 1 and 2 cm, and 10.4% were >2 cm. mpMRI missed at least one clinically significant focus in 34% of patients overall, and in 45% of men with multifocal lesions. On multivariate analysis, smaller, low-grade, multifocal, nonindex tumors with lower prostate-specific antigen density were more likely to be missed. Limitations include selection bias in a prostatectomy cohort, lack of specificity data, an imperfect co-registration process, and uncertain clinical significance for undetected lesions.

Conclusions

mpMRI detects less than half of all and less than two-thirds of clinically significant CaP foci. The moderate per-lesion sensitivity and significant proportion of men with undetected tumor foci demonstrate the current limitations of mpMRI.

Patient summary

Magnetic resonance imaging of the prostate before surgical removal for prostate cancer finds less than half of all individual prostate cancer tumors. Large, solitary, aggressive tumors are more likely to be visualized on imaging.  相似文献   
50.

Background and aims

Heparin-binding EGF-like growth factor (HB-EGF) is a representative EGF family member that interacts with EGFR under diverse stress environment. Previously, we reported that the HB-EGF-targeting using antisense oligonucleotide (ASO) effectively suppressed an aortic aneurysm in the vessel wall and circulatory lipid levels. In this study, we further examined the effects of the HB-EGF ASO administration on the development of hyperlipidemia-associated atherosclerosis using an atherogenic mouse model.

Methods and results

The male and female LDLR deficient mice under Western diet containing 21% fat and 0.2% cholesterol content were cotreated with control and HB-EGF ASOs for 12 weeks. We observed that the HB-EGF ASO administration effectively downregulated circulatory VLDL- and LDL-associated lipid levels in circulation; concordantly, the HB-EGF targeting effectively suppressed the development of atherosclerosis in the aorta. An EGFR blocker BIBX1382 administration suppressed the hepatic TG secretion rate, suggesting a positive role of the HB-EGF signaling for the hepatic VLDL production. We newly observed that there was a significant improvement of the insulin sensitivity by the HB-EGF ASO administration in a mouse model under the Western diet as demonstrated by the improvement of the glucose and insulin tolerances.

Conclusion

The HB-EGF ASO administration effectively downregulated circulatory lipid levels by suppressing hepatic VLDL production rate, which leads to effective protection against atherosclerosis in the vascular wall.  相似文献   
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