Long-term outcomes after ascending aortic replacement and aortic root replacement for type A aortic dissection

 Open in a separate windowOBJECTIVESWe investigated whether the selective use of supracoronary ascending aorta replacement achieves late outcomes comparable to those of aortic root replacement for acute Stanford type A aortic dissection (TAAD).METHODSPatients who underwent surgery for acute type A aortic dissection from 2005 to 2018 at the Helsinki University Hospital, Finland, were included in this analysis. Late mortality was evaluated with the Kaplan–Meier method and proximal aortic reoperation, i.e. operation on the aortic root or aortic valve, with the competing risk method.RESULTSOut of 309 patients, 216 underwent supracoronary ascending aortic replacement and 93 had aortic root replacement. At 10 years, mortality was 33.8% after aortic root replacement and 35.2% after ascending aortic replacement (P = 0.806, adjusted hazard ratio 1.25, 95% confidence interval, 0.77–2.02), and the cumulative incidence of proximal aortic reoperation was 6.0% in the aortic root replacement group and 6.2% in the ascending aortic replacement group (P = 0.65; adjusted subdistributional hazard ratio 0.53, 95% confidence interval 0.15–1.89). Among 71 propensity score matched pairs, 10-year survival was 34.4% after aortic root replacement and 36.2% after ascending aortic replacement surgery (P = 0.70). Cumulative incidence of proximal aortic reoperation was 7.0% after aortic root replacement and 13.0% after ascending aortic replacement surgery (P = 0.22). Among 102 patients with complete imaging data [mean follow-up, 4.7 (3.2) years], the estimated growth rate of the aortic root diameter was 0.22 mm/year, that of its area 7.19 mm²/year and that of its perimeter 0.43 mm/year.CONCLUSIONSWhen stringent selection criteria were used to determine the extent of proximal aortic reconstruction, aortic root replacement and ascending aortic replacement for type A aortic dissection achieved comparable clinical outcomes.     

Cerebral White Matter Maturation Patterns in Preterm Infants: An MRI T2 Relaxation Anisotropy and Diffusion Tensor Imaging Study

BACKGROUND AND PURPOSE

Preterm birth is associated with worse neurodevelopmental outcome, but brain maturation in preterm infants is poorly characterized with standard methods. We evaluated white matter (WM) of infant brains at term‐equivalent age, as a function of gestational age at birth, using multimodal magnetic resonance imaging (MRI).

METHODS

Infants born very preterm (<32 weeks gestation) and late preterm (33‐36 weeks gestation) were scanned at 3 T at term‐equivalent age using diffusion tensor imaging (DTI) and T2 relaxometry. MRI data were analyzed using tract‐based spatial statistics, and anisotropy of T2 relaxation was also determined. Principal component analysis and linear discriminant analysis were applied to seek the variables best distinguishing very preterm and late preterm groups.

RESULTS

Across widespread regions of WM, T2 is longer in very preterm infants than in late preterm ones. These effects are more prevalent in regions of WM that myelinate earlier and faster. Similar effects are obtained from DTI, showing that fractional anisotropy (FA) is lower and radial diffusivity higher in the very preterm group, with a bias toward earlier myelinating regions. Discriminant analysis shows high sensitivity and specificity of combined T2 relaxometry and DTI for the detection of a distinct WM development pathway in very preterm infants. T2 relaxation is anisotropic, depending on the angle between WM fiber and magnetic field, and this effect is modulated by FA.

CONCLUSIONS

Combined T2 relaxometry and DTI characterizes specific patterns of retarded WM maturation, at term equivalent age, in infants born very preterm relative to late preterm.     

Monitoring of gliomas in vivo by diffusion MRI and 1H MRS during gene therapy‐induced apoptosis: interrelationships between water diffusion and mobile lipids

The measurement of water diffusion by diffusion‐weighted MRI (DWI) in vivo offers a non‐invasive method for assessing tissue responses to anti‐cancer therapies. The pathway of cell death after anti‐cancer treatment is often apoptosis, which leads to accumulation of mobile lipids detectable by ¹H MRS in vivo. However, it is not known how these discrete MR markers of cell death relate to each other. In a rodent tumour model [i.e. ganciclovir‐treated herpes simplex thymidine kinase (HSV‐tk) gene‐transfected BT4C gliomas], we studied the interrelationships between water diffusion (Trace{D}) and mobile lipids during apoptosis. Water diffusion and water‐referenced concentrations of mobile lipids showed clearly increasing and interconnected trends during treatment. Of the accumulating ¹H MRS‐visible lipids, the fatty acid ? CH ?CH ? groups and cholesterol compounds showed the strongest associations with water diffusion (r² = 0.30; P < 0.05 and r² = 0.48; P < 0.01, respectively). These results indicate that the tumour histopathology and apoptotic processes during tumour shrinkage can be interrelated in vivo by DWI of tissue water and ¹H MRS of mobile lipids, respectively. However, there is considerable individual variation in the associations, particularly at the end of the treatment period, and in the relative compositions of the accumulating NMR‐visible lipids. The findings suggest that the assessment of individual treatment response in vivo may benefit from combining DWI and ¹H MRS. Absolute and relative changes in mobile lipids may indicate initiation of tumour shrinkage even when changes in tissue water diffusion are still small. Conversely, greatly increased water diffusion probably indicates that substantial cell decomposition has taken place in the tumour tissue when the ¹H MRS resonances of mobile lipids alone can no longer give a reliable estimate of tissue conditions. Copyright © 2008 John Wiley & Sons, Ltd.     

The mechanism of primary patellar dislocation: Trauma history of 126 patients

Background and purpose Several mechanisms are responsible for patellar dislocation. We investigated how the primary pathomechanism relates to patient characteristics and the outcome.Methods 126 patients (81 females) with primary patellar dislocation reported the knee position before the episode, the movement during it, and whether the patella was locked in dislocation. The median age was 20 (9–47) years. The subjective outcome and Kujala, Hughston VAS, and Tegner scores were evaluated after an average of 7 years.Results 102 patients moved to flexion during the dislocation, 98 from a straight start and 4 from a well-bent start. 10 extended the knee from a well-bent start; they were older (mean 25 vs. 19 years) and more often had low trauma energy (5/10 vs. 15/102) and a locked dislocation (10/10 vs. 50/102). 4 had a direct hit to the knee and 1 only rotated it while stretching. 24 of 60 patients with open growth line of the tibial tubercle and 43 of 66 with closed tubercle had locked primary dislocation (p = 0.005). 33% of girls, 52% of boys, 57% of women, and 71% of men had locked primary dislocation. There was no correlation between trauma mechanism and outcome.Interpretation Movement to flexion occurred in 84% of primary patellar dislocations and movement to extension in 8%. Spontaneous patellar relocation is common in skeletally immature girls and locked dislocation is common in skeletally mature men.     

Multi-locus transcranial magnetic stimulation—theory and implementation

Background

Transcranial magnetic stimulation (TMS) is a non-invasive brain stimulation method: a magnetic field pulse from a TMS coil can excite neurons in a desired location of the cortex. Conventional TMS coils cause focal stimulation underneath the coil centre; to change the location of the stimulated spot, the coil must be moved over the new target. This physical movement is inherently slow, which limits, for example, feedback-controlled stimulation.

The Effect of Stimulus Parameters on TMS–EEG Muscle Artifacts

BackgroundWhen transcranial magnetic stimulation (TMS) is delivered close to the lateral aspects of the head, large-amplitude (～10–1000 μV) biphasic electroencephalographic (EEG) deflections, peaking at around 4–10 and 8–20 ms, appear.ObjectiveTo characterize the spatiotemporal features of these artifacts, to quantify the effect of stimulus parameters on them, and thus, to study the feasibility of different measurement procedures to decrease the artifacts online. Furthermore, to show that these deflections, when measured with a sample-and-hold system, mainly result from excitation of cranial muscles.MethodsThree subjects received TMS to 16 sites over the left hemisphere. TMS-compatible EEG was recorded simultaneously. Four other subjects received TMS to M1 with different coil rotation and tilt angles and stimulation intensities. We also stimulated a conductive phantom and recorded simultaneous EEG to exclude the possibility of residual electromagnetic artifacts.ResultsThe artifacts were largest when the stimulator was placed above cranial muscles, whereas stimulation of relatively central sites far from the muscles produced muscle artifact-free data. The laterally situated EEG channels were most severely contaminated. The artifacts were significantly reduced when reducing the intensity or when tilting or rotating the coil so that coil wings moved further away from the temporal muscle, while brain responses remained visible. Stimulation of the phantom did not produce such large-amplitude biphasic artifacts.ConclusionAltering the stimulation parameters can reduce the described artifact, while brain responses can still be recorded. The early, laterally appearing, large biphasic TMS-evoked EEG deflections recorded with a sample-and-hold system are caused by cranial muscle activation.     

Alexithymia and suicidal ideation: a 12-month follow-up study in a general population

Alexithymic features are often associated with depression, which is the most important risk factor for suicidal behaviors. Nevertheless, little is known about the associations between alexithymia and suicidality. In this 12-month follow-up study we investigated the relationship between alexithymia and suicidal ideation in a sample of the general population (N = 1,563) using the 20-item Toronto Alexithymia Scale (TAS-20) and the 21-item Beck Depression Inventory (BDI). Suicidal ideation was more common among subjects with alexithymia than among nonalexithymic subjects (32% v 9% at baseline and 36% v 9% after 12 months). In cross-sectional analyses, alexithymia associated with the presence of suicidal ideation even after adjustment for sex, age, and several psychosocial and socioeconomic factors and the presence of depression. Moreover, after adjustment for depression at baseline, the decrease and increase in alexithymic features during the study period associated independently with recovery from and the occurrence of suicidal ideation, respectively. Nevertheless, these associations were no longer independent when adjusted for concomitant changes in the level of depressive symptoms. In conclusion, if depression presents alexithymic features the subject has an additive impact on the risk of suicidal ideation.     

Life satisfaction and depression in a 15-year follow-up of healthy adults

OBJECTIVE: The aim of this study was to investigate the cross-sectional and longitudinal relationship between life satisfaction and depressive symptoms in healthy adults. METHOD: This is a 15-year prospective cohort study with a nationwide sample of healthy Finnish adults (N = 9679), aged 18-45, who responded to postal questionnaires in 1975, 1981 and 1990 including a 4-item life satisfaction (LS) scale (range 4-20) and, in 1990, the 21-item Beck Depression Inventory (BDI). RESULTS: A strong linear association was found between concurrent LS and BDI scales (r = 0.6). With an LS cut-off point of 11/12, moderate/severe depression (BDI > or = 19) was detected with 87% sensitivity, 88 % specificity and a 94% area under the ROC curve. Longitudinally, a strongly increased risk of moderate/severe depression in 1990 was observed among the dissatisfied (LS 12-20) compared with the satisfied (LS 4-6) in 1975 (OR = 6.7; 95 %CI 4.2-10.9) and in 1981 (OR = 10.4; 6.1-17.6). CONCLUSION: The 4-item LS scale can identify a group of healthy people from the general population with a high risk of having or developing depressive symptoms. Since low life satisfaction also indicates an elevated risk of other adverse health outcomes, the assessment of subjective well-being should be encouraged both in surveys and in clinical practice.