Background
Acute type A aortic dissection (ATAAD) is relatively uncommon in dialysis patients, and characteristics and repair outcomes are not fully understood.
Patients and methods
Patients with ...ATAAD (
n
= 960) were divided into a dialysis group (
n
= 19) and non-dialysis group (
n
= 941), depending on whether they required dialysis for preoperative end-stage renal disease (ESRD). Hospital charts and imaging data were reviewed, and characteristics and outcomes were compared between the groups. Segmental aortic wall or intima/media flap calcification in the thoracic and abdominal aorta was assessed in the dialysis patients.
Results
The leading primary causes of ESRD were polycystic kidney disease (
n
= 5) and chronic glomerulonephritis (
n
= 5). There were no significant differences (dialysis group vs. non-dialysis group) in age (60.5 vs. 64.5 years), preoperative hemodynamics, or organ ischemia. Dialysis patients were more likely to have an entry tear in the aortic arch (42% vs. 15%,
p
= 0.003). These patients showed moderate-to-severe calcification (multiple focal or single focal calcification > 10 mm) in the ascending aorta (17%), aortic arch (61%), descending aorta (67%), and abdominal aorta (83%). Arch replacement was common in this group (37% vs. 18%,
p
= 0.030). Although in-hospital mortality was increased in this group (21% vs. 7%,
p
= 0.059), morbidities did not differ significantly. Six-year survival was 60.3 ± 13.4% and 78.8 ± 1.6%, respectively (
p
= 0.01).
Conclusions
Dialysis patients tend to have aortic calcification and a primary tear in the aortic arch. Outcomes are acceptable.
Hemodynamic management based on cerebral autoregulation range is a possible strategy for preserving major organ perfusion during cardiovascular surgery. The purpose of this study was to evaluate the ...relation of vascular properties with lower limit of cerebral autoregulation (LLA). LLA was monitored in 66 patients undergoing cardiovascular surgery using near‐infrared spectroscopy. To determine the clinical importance of LLA monitoring, association of blood pressure excursions below LLA and acute kidney injury (AKI) was evaluated. Flow‐mediated dilation (FMD) and pulse wave velocity (PWV) were measured for the evaluation of endothelial function and aortic stiffness. Variables associated with LLA were evaluated. Excluding patients on hemodialysis, there were 15 patients (25.9%) who developed AKI. Blood pressure excursions below LLA were higher in patients who developed AKI (4.55 mm Hg × hr vs. 1.23 mm Hg × hr, P = .017). In the univariate analysis, prevalence of ischemic heart disease (No IHD: 53 ± 13.0 mm Hg vs. IHD: 60.0 ± 13.6 mm Hg, P = .056) and FMD (r = −0.42, 95% CI −0.61 to −0.19, P < .001) were associated with LLA before cardiopulmonary bypass (CPB). During CPB, calcium channel blocker (No Ca blocker: 42 ± 10.6 mm Hg vs. Ca blocker: 49 ± 14.3 mm Hg, P = .033), diabetes (no DM: 44 ± 13.2 mm Hg vs. DM: 55 ± 10.0 mm Hg, P = .024), FMD (r = −0.32, 95% CI −0.55 to −0.05, P = .021), and PWV (r = 0.28, 95% CI 0.012 to 0.513, P = .041) were associated with LLA. Multivariate analysis showed that FMD was correlated with LLA before CPB (r = −2.19, 95% CI −3.621 to −0.755, P = .003), while PWV was correlated with LLA during CPB (r = 0.01, 95% CI 0.001‐0.019, P = .023). Endothelial function and aortic stiffness may be important factors in determining LLA at different phases in cardiovascular surgery.
Cerebral autoregulation monitoring may provide guidance for hemodynamic management to preserve major organ perfusion in cardiovascular surgery.Blood pressure management below the lower limit of cerebral autoregulation (LLA) was associated with postoperative acute kidney injury. Endothelial function and vascular stiffness were independent variables correlated with (LLA) during different phases of perioperative period.
A 78-year-old man presented with severe stage 3 (Fontaine IV, Rutherford 5, W1 I3 FI0) right limb ischemia. Although his artery was completely occluded from below the right external iliac to the ...popliteal artery, collateral circulation from the right lateral femoral circumflex artery was well developed and supplied the lower extremity arteries. We selected an uncommon crossover bypass strategy with the left common femoral artery to the right lateral femoral circumflex artery to improve lower extremity perfusion via indirect revascularization. Bypass using the lateral femoral circumflex artery as an outflow is an option for patients with major lower extremity artery occlusions.
We recently identified a nuclear-encoded miRNA (miR-181c) in cardiomyocytes that can translocate into mitochondria to regulate mitochondrial gene mt-COX1 and influence obesity-induced cardiac ...dysfunction through the mitochondrial pathway. Because liver plays a pivotal role during obesity, we hypothesized that miR-181c might contribute to the pathophysiological complications associated with obesity. Therefore, we used miR-181c/d-/- mice to study the role of miR-181c in hepatocyte lipogenesis during diet-induced obesity. The mice were fed a high-fat (HF) diet for 26 weeks, during which indirect calorimetric measurements were made. Quantitative PCR (qPCR) was used to examine the expression of genes involved in lipid synthesis. We found that miR-181c/d-/- mice were not protected against all metabolic consequences of HF exposure. After 26 weeks, the miR-181c/d-/- mice had a significantly higher body fat percentage than did wild-type (WT) mice. Glucose tolerance tests showed hyperinsulinemia and hyperglycemia, indicative of insulin insensitivity in the miR-181c/d-/- mice. miR-181c/d-/- mice fed the HF diet had higher serum and liver triglyceride levels than did WT mice fed the same diet. qPCR data showed that several genes regulated by isocitrate dehydrogenase 1 (IDH1) were more upregulated in miR-181c/d-/- liver than in WT liver. Furthermore, miR-181c delivered in vivo via adeno-associated virus attenuated the lipogenesis by downregulating these same lipid synthesis genes in the liver. In hepatocytes, miR-181c regulates lipid biosynthesis by targeting IDH1. Taken together, the data indicate that overexpression of miR-181c can be beneficial for various lipid metabolism disorders.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
We recently described a novel regulatory role for histone deacetylase 2 (HDAC2) in protecting endothelial cells from oxidized low-density lipoprotein (OxLDL)-induced injury. In this study, we ...examined the effects of endothelial-specific HDAC2 overexpression on endothelial-dependent vasorelaxation and atherogenesis in vivo.
Endothelial-specific HDAC2-overexpressing transgenic mice (HDAC2-Tg) were generated under control of the Tie2 promoter. An atherosclerosis model was produced by injecting HDAC2-Tg and wild-type (WT) mice with adeno-associated virus encoding a PCSK9 gain-of-function mutant under control of a liver-specific promoter and feeding them a high-fat diet for 12 weeks. Aortic stiffness in vivo was determined by measuring pulse wave velocity. Wire myography was used to measure endothelium dependent (acetylcholine) and independent (sodium nitroprusside) relaxation in isolated mice aortas. Atherosclerotic plaque burden in aortas was determined by Oil Red O staining and protein expression was determined by western blotting.
At baseline, HDAC2-Tg mice had normal mean arterial blood pressure (MAP) and body weight, but pulse wave velocity (PWV), an inverse measure of vascular health and stiffness, was decreased, suggesting that their vessels were more compliant. Moreover, basal nitric oxide production was enhanced in the vessels of HDAC2-Tg mice as compared to that in WT controls, although no significant differences in acetylcholine (endothelial component)- or sodium nitroprusside (non-endothelial component)-mediated relaxation were observed. However, after exposure to OxLDL, aortas from HDAC2-Tg mice exhibited greater acetylcholine-induced relaxation than did those from WT mice. Thus, endothelial-specific vasodilator production was enhanced despite oxidative injury. Atherosclerosis induction in WT mice led to a significant increase in PWV, but in HDAC2-Tg mice, PWV and MAP remained unchanged. Further, aortic rings from HDAC2-Tg exhibited better endothelial-dependent vascular relaxation than did those from WT mice, but not when treated with nitric oxide synthase inhibitor L-NAME. Finally, plaque burden, determined by Oil red O staining, was significantly increased in WT, but not HDAC2-Tg mice, subjected to the atherogenic model. Deletion of endothelial HDAC2 led to impaired endothelial cell-dependent vascular relaxation and increased PWV, compared with those in littermate controls.
HDAC2 protects against endothelial dysfunction and atherogenesis induced by oxidized lipids. Hence, overexpression or activation of HDAC2 represents a novel therapy for endothelial dysfunction and atherosclerosis. HDAC2-Tg mice provide an opportunity to determine the role of endothelial HDAC2 in vascular endothelial homeostasis.
Background The identification of large‐artery stiffness as a major, independent risk factor for cardiovascular disease–associated morbidity and death has focused attention on identifying therapeutic ...strategies to combat this disorder. Genetic manipulations that delete or inactivate the translin/trax microRNA‐degrading enzyme confer protection against aortic stiffness induced by chronic ingestion of high‐salt water (4%NaCl in drinking water for 3 weeks) or associated with aging. Therefore, there is heightened interest in identifying interventions capable of inhibiting translin/trax RNase activity, as these may have therapeutic efficacy in large‐artery stiffness. Methods and Results Activation of neuronal adenosine A2A receptors (A2ARs) triggers dissociation of trax from its C‐terminus. As A2ARs are expressed by vascular smooth muscle cells (VSMCs), we investigated whether stimulation of A2AR on vascular smooth muscle cells promotes the association of translin with trax and, thereby increases translin/trax complex activity. We found that treatment of A7r5 cells with the A2AR agonist CGS21680 leads to increased association of trax with translin. Furthermore, this treatment decreases levels of pre‐microRNA‐181b, a target of translin/trax, and those of its downstream product, mature microRNA‐181b. To check whether A2AR activation might contribute to high‐salt water–induced aortic stiffening, we assessed the impact of daily treatment with the selective A2AR antagonist SCH58261 in this paradigm. We found that this treatment blocked aortic stiffening induced by high‐salt water. Further, we confirmed that the age‐associated decline in aortic pre‐microRNA‐181b/microRNA‐181b levels observed in mice also occurs in humans. Conclusions These findings suggest that further studies are warranted to evaluate whether blockade of A2ARs may have therapeutic potential in treating large‐artery stiffness.
Clinical characteristics and treatment outcomes of acute type A aortic dissection with D-dimer elevation have not been clarified.
D-dimer was measured preoperatively within 24 hours of symptom onset ...in 262 patients with acute type A aortic dissection. The median (and interquartile range) admission D-dimer concentration in our total patient group was 26.7 (8.3-85.9) μg/mL. Median (interquartile range) D-dimer concentrations were 5.0 (2.6-18.0) μg/mL for complete false lumen thrombosis (n=33), 60.9 (19.4-160.4) μg/mL for partial thrombosis (n=81), 26.5 (10.0-70.6) μg/mL for a patent false lumen (n=131), and 8.7 (3.2-26.9) μg/mL for ulcerlike projection (n=17) (
0.01). With a D-dimer concentration of ≤8.3 μg/mL representing the lower quartile, we then investigated predictors of a low D-dimer level. Multivariate analysis showed dissection limited to the ascending aorta (
0.01; odds ratio, 9.81) or descending aorta (
0.01; odds ratio, 7.68), a completely thrombosed false lumen (
0.01; odds ratio, 4.02), and absence of brain ischemia (
0.013; odds ratio, 4.74) to be predictors of the lower D-dimer concentration. Compared with patients with a low D-dimer concentration (≤8.3 μg/mL, n=66), patients with a D-dimer concentration >8.3 μg/mL (n=196) had a reduced preoperative platelet count and increased operation time and transfusion volume. In-hospital mortality was elevated in this group (1.5% versus 11.2%;
0.031), although 7-year survival did not differ for hospital survivors (lower versus higher, 93.1% versus 79.1%;
=0.21).
D-dimer concentrations are strongly influenced by the extent of dissection and false lumen status. Operative risks are increased in patients with a relatively high D-dimer concentration.
Median sternotomy is the standard approach for coronary artery bypass grafting. Herein, we performed off-pump coronary artery bypass grafting via left anterior thoracotomy from the 4th costal space ...in an unstable angina pectoris patient with total laryngectomy and a permanent tracheostoma. In this patient, median sternotomy had high risks of surgical-site infection and tracheal injury. To avoid these risks, we selected left anterior thoracotomy. Initially, it was difficult to expose the ascending aorta and postdescending branch. With extension of the skin incision to the median area and division of the 5th and 6th ribs and costal arch, we could expose the anastomotic sites, including the ascending aorta and postdescending branch, without median sternotomy conversion. We performed multiple coronary artery bypass graft procedures safely. This approach might be an additional surgical option in patients with total laryngectomy and a permanent tracheostoma.
Zone 2 anastomosis with total cervical branch reconstruction for acute type A aortic dissection and aortic arch aneurysms became possible after stent-graft introduction. This may be an easier ...procedure and reduce the risk of recurrent laryngeal nerve palsy. Therefore, this study aimed to compare the outcomes between Zone 2 and Zone 3 distal anastomoses.
After evaluating the patient data in our institute between April 2016 and April 2022, the patients in whom distal anastomosis was performed at Zone 2 with a stent-graft were defined as the Zone 2 group (n = 70). The patients in whom distal anastomosis was performed at Zone 3 were defined as the Zone 3 group (n = 24).
The incidence of new-onset recurrent nerve palsy was one patient (1.4%) in the Zone 2 group and six patients (25.0%) in the Zone 3 group (p < 0.001). The lower body perfusion arrest time was 44.3 ± 9.1 min in the Zone 2 group and 52.9 ± 12.8 min in the Zone 3 group (p = 0.005). There were no significant differences in in-hospital mortality and morbidities. Multivariable analysis showed that only age was an independent predictor of overall mortality.
Performing distal anastomosis at Zone 2 with a frozen elephant trunk or stent-graft reduced the lower body perfusion arrest time and possibly prevented recurrent nerve palsy.
PDF
