One-Year Single-Center Results of the Multilayer Flow Modulator Stents for the Treatment of Type B Aortic Dissection.

PURPOSE: To report a single-center series of patients with type B aortic dissection treated with the Multilayer Flow Modulator (MFM). MATERIALS AND METHODS: Over a 36-month period, 23 patients (median age 53 years; 20 men) with complicated type B aortic dissections (2 acute, 5 subacute, and 16 chronic) were treated with the MFM. Primary endpoints of rupture or dissection-related death, overall mortality, and reintervention were evaluated using the Kaplan-Meier method; estimates for freedom from the endpoints are reported with the 95% confidence interval (CI). Secondary outcomes included technical success, adverse events, and aortic remodeling. Clinical and imaging data were collected preoperatively, directly postoperatively, and annually to 36 months for analysis using computational fluid dynamics (CFD). RESULTS: Initial technical success was 91.3%. The estimates of the endpoints at 12 months were 100% for freedom from rupture or aortic-related death, 95.7% for freedom from overall mortality, and 91.3% for freedom from reintervention. No device-related neurological or systemic complications occurred, and no additional reinterventions were needed during follow-up. A total of 144 branches overstented by the MFM remained patent. Morphologic analysis of the aortic dissection showed progressive true lumen volume increase (75.9%, p<0.001) with concomitant false lumen volume decrease (42.8%, p<0.001); the CFD analyses showed increased laminar flow. CONCLUSION: In the current series, the MFM provided a safe and feasible treatment option for complicated acute, subacute, and chronic type B aortic dissections, with high technical success, low mortality, and active aortic remodeling. Further studies should elucidate the long-term safety of the MFM and its effectiveness in a larger patient cohort.

Geometric Analysis of Type B Aortic Dissections Shows Aortic Remodeling After Intervention Using Multilayer Stents.

Recently, multilayer stents for type B aortic dissections (TBAD) have been proposed to decrease false lumen flow, increase and streamline true lumen flow, and retain branch vessel patency. We aimed to provide a protocol with standardized techniques to investigate aortic remodeling of TBAD by multilayer flow modulators (MFM) in static geometric and hemodynamic analyses. Combining existing literature and new insights, a standardized protocol was designed. Using pre- and postoperative CT scans, geometric models were constructed, lumen dimensions were calculated, computational fluid dynamics (CFD) models were composed, and velocity and pressures were calculated. Sixteen TBAD cases treated with MFM were included for analysis. For each case, aortic remodeling was analyzed using post-processing medical imaging software. After 3D models were created, geometrical anatomical measurements were performed, and meshes for finite element analysis were generated. MFM cases were compared pre- and postoperatively; true lumen volumes increased (p < 0.001), false lumen volumes decreased (p = 0.001), true lumen diameter at the plane of maximum compression (PMC) increased (p < 0.001), and false lumen index decreased (p = 0.008). True lumen flow was streamlined, and the overall fluid velocity and pressures decreased (p < 0.001 and p = 0.006, respectively). This protocol provided a standardized method to evaluate the effects of MFM treatments in TBAD on geometric analyses, PMC, and CFD outcomes.

Aortic Remodeling After Total Endovascular Aortic Repair With Multilayer Stents: Computational Fluid Dynamics Analysis of Aortic Remodeling Over 3 Years of Follow-up.

PURPOSE: To report Multilayer Flow Modulator (MFM) implantation from the sinotubular junction to the distal infrarenal aorta in the treatment of type B aortic dissection (TBAD) and demonstrate aortic remodeling using computational fluid dynamics (CFD) analysis over the course of 3-year follow-up. CASE REPORT: A hypertensive patient with complicated TBAD required thoracic endovascular aortic repair due to severe thoracic pain associated with rapid progression of the false lumen aneurysm toward the distal aortic arch. Under general anesthesia, 2 aortic multilayer stents were placed over a 0.035-inch stiff guidewire in the compressed true lumen. The aorta was covered with 2 MFM stents between the sinotubular junction and the distal infrarenal aorta. Serial computed tomography scans showed progressive remodeling of the entire dissected aortic wall, with an excellent result at 24 months. Morphological and CFD vascular analysis confirmed the aortic remodeling, with a false lumen index drop from a preoperative 4.04 to 0.01 at 36 months. CONCLUSION: Endovascular aortic repair with multilayer stents is a promising treatment for complicated TBAD due to the unique ability of these devices to stabilize the entire aortic wall without compromising the flow in the major aortic side branches.

Sex differences in the prediction of metabolic burden from physiological responses to stress.

BACKGROUND: Heightened or prolonged physiological responses to stress may contribute to the development or progression of metabolic abnormalities. PURPOSE: This study aims to examine the prospective relationships between stress responses and metabolic burden, and to determine whether age and/or sex moderate these relationships. METHODS: One hundred ninety-nine healthy men and women (M(age) = 41 ± 11.5) were exposed to four stressors while blood pressure, heart rate, and heart rate variability were obtained. Residual change scores for reactivity (stress - baseline) and recovery (post-stress - baseline) scores were computed. Metabolic burden refers to the number of metabolic parameters for which participants were in the highest quartile (lowest for high-density lipoprotein cholesterol) for their sex. Metabolic burden was reassessed in 136 participants 3 years later. RESULTS: Greater parasympathetic withdrawal in response to stress was associated with increased metabolic burden, though this was evident mostly in men. In women, dampened autonomic responses to stress were associated with higher metabolic burden. CONCLUSIONS: Cardiac autonomic responses to stress predict future metabolic abnormalities, though the direction of effect differs according to sex.

Psychological impact of surveillance in patients with a defibrillator lead under advisory: a prospective evaluation.

BACKGROUND: Implantable cardioverter defibrillator (ICD) leads are subject to technical failures and the impact of the resulting public advisories on patient welfare is unclear. The psychological status of patients who received an advisory for their Medtronic Fidelis ICD lead (Medtronic Inc., Minneapolis, MN, USA) and followed either by self-surveillance for alarm or home monitoring with CareLink was evaluated prospectively and compared to patients with ICDs not under advisory. METHODS: One hundred sixty consecutive consenting patients (90 alarms, 24 Carelinks, 46 controls) were recruited within 1.5 years of advisory notification. Advisory patients were seen immediately before being told that the automatic lead surveillance utilized since the advisory had been inadequate in warning of impending fracture, as well as 1 and 6 months after programming was optimized. Depression, anxiety, quality of life (QoL), and ICD-related concerns were assessed. RESULTS: Symptoms of depression and state anxiety were experienced by 31% and 48% of patients, respectively. QoL was impaired on all subscales. No significant group differences in distress and ICD-related concerns emerged at baseline or at follow-up. At baseline, alarm patients reported greater limitations because of body pain compared to controls (P < 0.05). All patients showed a significant reduction in body pain-related QoL at the final versus first two evaluations (P < 0.001). Advisory patients were significantly less satisfied with surveillance at follow-up than at baseline (P < 0.05). CONCLUSIONS: There was limited evidence for worse psychosocial functioning in those at risk for ICD lead fracture, irrespective of surveillance method. However, many control and advisory patients experienced chronic distress for which counseling may prove beneficial.

Impact of diet and stress on the development of preeclampsia-like symptoms in p57kip2 mice.

The cyclin-dependent kinase inhibitor p57(kip2) regulates the cell cycle of trophoblastic cells. It has been established by a Japanese group that the heterozygous p57(kip2) knockout (p57(-/+)) mice are a good model of preeclampsia as they develop hypertension, proteinuria, and placental pathology. However, apart from the placental pathology, we could not observe these symptoms in our laboratory. Hence, we investigated the impact of diet and stress on this model. To do so, we compared the effects of the Japanese diet to that of the North American diet used by our animal facility. Furthermore, the impact of stress was determined by placing the mice in a restraining device before and at the end of gestation. Although the Japanese diet did not have any impact on blood pressure or proteinuria, the mice did develop endothelial dysfunction, left ventricular hypertrophy, as well as increased placental pathology. Also, all mice had smaller litters when fed the Japanese diet. However, stress response of these mice was not increased during gestation; in fact, a decrease was observed in the p57(-/+) mice, suggesting that this was probably not a player in the development of the pathology. Taken together, these results suggest that other environmental factors may have been implicated in the development of preeclampsia-like symptoms in this animal model. Moreover, we demonstrated that placental pathology and genetic factors are not sufficient to trigger preeclampsia-like symptoms in this model and that the diet might play an important part in the development of this multifactorial disease.