Thrombocytopenia after Aortic Valve Replacement Using Sutureless Valves.

Background: Sutureless valves are widely used in aortic valve replacement surgery, with Perceval valves and Intuity valves being particularly prominent. However, concerns have been raised about postoperative thrombocytopenia with Perceval valves (Corcym, UK). We conducted a comparative analysis with the Intuity valve (Edwards Lifesciences, USA), and assessed how thrombocytopenia affected patient and transfusion outcomes. Methods: Among 595 patients who underwent aortic valve replacement from June 2016 to March 2023, sutureless valves were used in 53 (Perceval: n=23; Intuity: n=30). Platelet counts were monitored during hospitalization and outpatient visits. Daily platelet count changes were compared between groups, and the results from patients who underwent procedures using Carpentier Edwards Perimount Magna valves were used as a reference group. Results: Compared to the Intuity group, the Perceval group showed a significantly higher amount of platelet transfusion (5.48±1.64 packs vs. 0.60±0.44 packs, p=0.008). During the postoperative period, severe thrombocytopenia (<50,000/µL) was significantly more prevalent in the Perceval group (56.5%, n=13) than in the Intuity group (6.7%, n=2). After initial postoperative depletion, daily platelet counts increased, with significant differences observed in the extent of improvement between the Perceval and Intuity groups (p<0.001). However, there was no significant difference in early mortality or the incidence of neurological complications between the 2 groups. Conclusion: The severity of postoperative thrombocytopenia differed significantly between the Perceval and Intuity valves. The Perceval group showed a significantly higher prevalence of severe thrombocytopenia and higher platelet transfusion volumes. However, thrombocytopenia gradually recovered during the postoperative period in both groups, and the early outcomes were similar in both groups.

Influence of Preoperative COVID-19 Vaccination on Outcomes After Coronary Artery Bypass Grafting-A Propensity Score-Matched Analysis.

BACKGROUND: Reports of intravascular thrombosis and cardiac complications have raised concerns about the safety of COVID-19 vaccinations, particularly in patients with high cardiovascular risk. Herein, we aimed to analyze the impact of preoperative COVID-19 vaccination on outcomes after coronary artery bypass grafting (CABG). METHODS AND RESULTS: Among 520 patients who underwent isolated CABG from 2020 to 2022, 481 patients (mean±SD age: 67±11 years, 86 women) whose COVID-19 vaccination status could be confirmed were included. A total of 249 patients who had not received any COVID-19 vaccine before CABG (never vaccinated group) and 214 patients who had completed primary vaccination (fully vaccinated group) were subjected to 1:1 propensity score matching, and 156 pairs of patients were matched. There was no significant difference in early mortality between the 2 groups after matching. After matching, overall survival (P=0.930) and major adverse cardiovascular and cerebrovascular event-free survival (P=0.636) did not differ between the 2 groups. One-year graft patency also did not differ significantly between the 2 groups; all patent grafts in 85/104 patients (82%) and 62/73 patients (85%) in the never vaccinated and fully vaccinated groups, respectively (P=0.685). Subgroup analysis showed equivalent overall and major adverse cardiovascular and cerebrovascular event-free survival among AstraZeneca and Pfizer vaccine recipients and between those with ≤30 days versus >30 days from vaccination to CABG. CONCLUSIONS: Despite the very high cardiovascular risk for patients undergoing CABG, COVID-19 vaccination did not affect major outcomes after CABG. Therefore, there is no reason for patients with coronary artery disease requiring CABG to avoid preoperative COVID-19 vaccination.

Acute type A aortic dissection features and outcomes in octogenarians: a propensity score analysis.

OBJECTIVES: The clinical characteristics and early outcomes of surgical repair in octogenarians with acute type A aortic dissection were compared with those in nonoctogenarians. METHODS: All patients who underwent emergency surgical repair for acute type A aortic dissection in our institution between 2003 and 2022 were included in this study. The patients were divided into an octogenarian group and a nonoctogenarian group. The patients in the 2 groups were propensity score matched at a ratio of 1:1. Before matching, the baseline characteristics were compared between 2 groups. The major complication and 30-day mortality rates were compared in the matched population. RESULTS: A total of 495 patients were screened, and 471 were included in the analysis, with 48 in the octogenarian group and 423 in the nonoctogenarian group. Before matching, DeBakey type II dissection was significantly more prevalent in the octogenarians (42% vs 14% in the octogenarians and nonoctogenarians, respectively, P < 0.001). Additionally, intramural haematomas (39.6% vs 14.4%, P < 0.001) were more prevalent in the octogenarians. However, severe aortic regurgitation (4.2% vs 15.4%, P = 0.046) and root enlargement (0% vs 13.7%, P = 0.009) were less prevalent in the octogenarians. After matching (36 pairs), the incidence of postoperative delirium was higher in the octogenarians (56% vs 25%, P = 0.027). However, there were no significant differences in 30-day and in-hospital mortality rates, intensive care unit stay or major complications, including stroke, paraplegia, respiratory complications, mediastinitis and haemodialysis. CONCLUSIONS: The octogenarians with acute type A aortic dissection had higher incidences of DeBakey type II dissection and intramural haematomas and lower incidences of severe aortic regurgitation and aortic root enlargement than the nonoctogenarians. Being an octogenarian was not associated with an increased risk of early major complications or mortality after surgery for acute type A aortic dissection.

Blood-brain barrier disruption imaging in postoperative cerebral hyperperfusion syndrome using DCE-MRI.

Little has been reported about the association between cerebral hyperperfusion syndrome (CHS) and blood-brain barrier (BBB) disruption in human. We aimed to investigate the changes in permeability after bypass surgery in cerebrovascular steno-occlusive diseases using dynamic contrast-enhanced MRI (DCE-MRI) and to demonstrate the association between CHS and BBB disruption. This retrospective study included 36 patients (21 hemispheres in 18 CHS patients and 20 hemispheres in 18 controls) who underwent combined bypass surgery for moyamoya and atherosclerotic steno-occlusive diseases. DCE-MRI and arterial spin labeling perfusion-weighted imaging (ASL-PWI) were obtained at the baseline, postoperative state, and discharge. Perfusion and permeability parameters were calculated at the MCA territory (CBF(territorial), Ktrans(territorial), Vp(territorial)) and focal perianastomotic area (CBF(focal), Ktrans(focal), Vp(focal)) of operated hemispheres. As compared with the baseline, both CBF(territorial) and CBF(focal) increased in the postoperative period and decreased at discharge, corresponding well to symptoms in the CHS group. Vp(focal) was lower in the postoperative period and at discharge, as compared with the baseline. In the control group, no parameters significantly differed among the three points. In conclusion, Vp at the focal perianastomotic area significantly decreased in patients with CHS during the postoperative period. BBB disruption may be implicated in the development of CHS after bypass surgery.

Improved clinical outcomes following introduction of an attending intensivist for patients admitted to the cardiac surgical intensive care unit after valvular heart surgery: a single-center experience.

Background: Although numerous studies have documented the improved clinical outcomes of patients undergoing cardiac surgery following introduction of attending intensivist, most of these studies included heterogeneous patient populations. We aimed to investigate the impact of an attending intensivist on the clinical outcomes of patients admitted to the cardiac surgical intensive care unit (CSICU) following valvular heart surgery. Methods: Patients who underwent valvular heart surgery between January 2007 and December 2012 (control group, n=337) were propensity matched (1:1) between January 2013 and June 2017 (intensivist group, n=407). Results: During the propensity score matching analysis, 285 patients were extracted from each group. Patients in the intensivist group underwent mechanical ventilation for a significantly shorter time than those in the control group (21.8±69.8 vs. 39.2±115.3 hours, P=0.021). More patients were extubated within 6 hours in the intensivist group than in the control group (53.7% vs. 42.8%, P=0.015). The incidence of ventilator-associated pneumonia (1.4% vs. 4.9%, P=0.031), cardiac arrest due to cardiac tamponade associated with post-cardiotomy bleeding (0.4% vs. 3.9%, P=0.002), and acute kidney injury (2.8% vs. 7.7%, P=0.011) in the intensivist group was significantly lower than that in the control group. The 30-day mortality rate of the intensivist group was significantly lower than that of the control group (2.1% vs. 6.7%, P=0.015). Conclusions: Critical care provided in the CSICU staffed by an attending intensivist is associated with a lower 30-day mortality rate and reduced incidence of postoperative complications.

Genome-wide association study identifies novel susceptibilities to adult moyamoya disease.

Genome-wide association study has limited to discover single-nucleotide polymorphisms (SNPs) in several ethnicities. Here, we investigated an initial GWAS to identify genetic modifiers predicting with adult moyamoya disease (MMD) in Koreans. GWAS was performed in 216 patients with MMD and 296 controls using the large-scale Asian-specific Axiom Precision Medicine Research Array. A subsequent fine-mapping analysis was conducted to assess the causal variants associated with adult MMD. A total of 489,966 out of 802,688 SNPs were subjected to quality control analysis. Twenty-one SNPs reached a genome-wide significance threshold (p = 5 × 10-8) after pruning linkage disequilibrium (r2 < 0.8) and mis-clustered SNPs. Among these variants, the 17q25.3 region including TBC1D16, CCDC40, GAA, RNF213, and ENDOV genes was broadly associated with MMD (p = 3.1 × 10-20 to 4.2 × 10-8). Mutations in RNF213 including rs8082521 (Q1133K), rs10782008 (V1195M), rs9913636 (E1272Q), rs8074015 (D1331G), and rs9674961 (S2334N) showed a genome-wide significance (1.9 × 10-8 < p < 4.3 × 10-12) and were also replicated in the East-Asian populations. In subsequent analysis, RNF213 mutations were validated in a fine-mapping outcome (log10BF > 7). Most of the loci associated with MMD including 17q25.3 regions were detected with a statistical power greater than 80%. This study identifies several novel and known variations predicting adult MMD in Koreans. These findings may good biomarkers to evaluate MMD susceptibility and its clinical outcomes.

A child who presented with cerebral infarction: Clipping combined with bypass surgery of a thrombosed giant aneurysm.

Background: Cerebral aneurysms are not common among children and most of them are presented with subarachnoid hemorrhage or mass effect. Here, we describe a rare case of a pediatric giant aneurysm presented with cerebral infarction. Case Description: A 38-month-old boy visited the emergency room due to left hemiparesis and left central type facial palsy. Initial magnetic resonance imaging showed acute cerebral infarction on the right basal ganglia and coronal radiata. Furthermore, a thrombosed aneurysm with a diameter of 30.57 mm at the frontal branch of the right middle cerebral artery was observed. A right pterional craniotomy with Sylvian dissection was performed. Superior and inferior divisions of the frontal branch originating from the aneurysm were identified. The superior division was cutoff from an aneurysm and clipping saving the inferior division was done. Subsequently, end-to-end anastomosis was done between a parietal branch of the superficial temporal artery and a superior division from the aneurysm. No acute complication from the operation was observed. Motor power of the left upper extremity recovered after rehabilitation, while fine motor impairment remained 6 months after the surgery. Conclusion: This case illustrates successful treatment of a pediatric giant aneurysm with extremely rare presentation of cerebral infarction, under a meticulous surgical plan and ad hoc modification.

Six-month stability following extensive alveolar bone augmentation by sausage technique.

BACKGROUND: Resorption of alveolar bone is a common sequela of tooth loss and presents a clinical problem, especially in the esthetic zone. When ridge resorption occurs, adequate bone augmentation is essential to obtain satisfactory esthetic results. The purpose of this study was to determine the increase and retention rate of bone height or width in patients who received extensive bone augmentation and to analyze factors affecting its prognosis and stability. METHODS: This study was performed on patients who received extensive bone augmentation by sausage technique at the Department of Oral and Maxillofacial Surgery at Ewha Womans University Mok-dong Hospital from January 1, 2018, to February 28, 2022. CBCT images were taken before and 6 months after surgery to compare the amount of increase in bone height or width at the graft site. They were measured using reliable points such as adjacent implants or cephalometric landmarks, inferior alveolar nerve canals as reference points. RESULTS: A total of 8 patients underwent extensive bone grafting during the given period (mean age was 53.75 years, 2 males and 6 females). Four patients received horizontal augmentation, and 4 received vertical augmentation. When divided by surgical site, 4 patients are in maxilla and 4 in mandible. The average amount of increase in bone width or bone height was 5.38 mm, and the retention rate was about 79.9% after 6 months. The retention rate of horizontal augmentation was 88.8%, which was higher than that of vertical augmentation, which was 74.5%. The maxillary area accounted for 92.2%, and the amount of bone resorption was lower than that of the mandibular area, which was 72.6%. The average stitch out period was about 2.4 weeks, and postoperative dehiscence was observed about 37.5% of the total, more frequently in the mandible (50.0%) than in the maxilla (25.0%). CONCLUSION: In conclusion, extensive bone augmentation achieved significant horizontal or vertical bone height or width increase, and the retention rate after 6 months was also high. In addition, surgery in the maxillary region showed a more successful bone augmentation than in the mandible, with a higher maintenance rate and fewer cases of dehiscence.

Population-Attributable Risk Fractions for Antiplatelets and Anticoagulants in Spontaneous Intracranial Hemorrhages.

INTRODUCTION: Concerns about spontaneous intracranial hemorrhages (sICHs) have increased over time with the increasing use of antithrombotic agents. Hence, we aimed to analyze the risk and risk fractions for antithrombotics in sICHs in South Korea. METHODS: From the National Health Insurance Service-National Sample Cohort including 1,108,369 citizens, 4,385 cases, aged 20 years or more and newly diagnosed as sICHs between 2003 and 2015, were included in this study. A total of 65,775 sICH-free controls were randomly selected at a ratio of 1:15 from individuals with the same birth year and sex according to a nested case-control study design. RESULTS: Although the incidence rate of sICHs started to decrease from 2007 onward, the use of antiplatelets, anticoagulants, and statins continued to increase. Antiplatelets (adjusted odds ratio [OR] 3.59, 95% confidence interval [CI] 3.18-4.05), anticoagulants (adjusted OR 7.46, 95% CI 4.92-11.32), and statins (adjusted OR 1.98, 95% CI 1.79-2.18) were significant risk factors for sICHs even after adjusting for hypertension, alcohol intake, and cigarette smoking. From 2003-2008 to 2009-2015, the population-attributable fractions changed from 28.0% to 31.3% for hypertension, from 2.0% to 3.2% for antiplatelets, and from 0.5% to 0.9% for anticoagulants. CONCLUSION: Antithrombotic agents are significant risk factors for sICHs, and their contribution is increasing over time in Korea. These findings are expected to draw the attention of clinicians to precautions to be taken when prescribing antithrombotic agents.

Elevated troponin I is associated with a worse long-term prognosis in patients undergoing beating-heart coronary surgery.

OBJECTIVES: The impacts of elevated troponin I levels after coronary artery bypass grafting (CABG) on long-term outcomes were investigated. METHODS: A total of 996 patients who underwent elective isolated CABG for stable or unstable angina were enrolled. Patients were divided into higher and lower groups based on 80th percentile postoperative peak troponin I (ppTnI) levels. The relationship between ppTnI and long-term clinical outcomes was analysed. RESULTS: The median ppTnI was 1.55 (2.74) ng/ml and was significantly higher in the conventional CABG subgroup than in the beating-heart CABG subgroup: 4.04 (4.71) vs 1.24 (1.99) ng/ml, P < 0.001. The 80th percentile of ppTnI was 3.3 ng/ml in the beating-heart CABG subgroup and 8.9 ng/ml in the conventional CABG subgroup. In the conventional CABG subgroup (n = 150), 10-year overall survival showed no significant difference between the higher (≥8.9 ng/ml) and lower (<8.9 ng/ml) ppTnI groups: 71% (10%) vs 76% (5%), P = 0.316. However, the beating-heart CABG subgroup (n = 846) showed significantly worse 10-year overall survival in the higher ppTnI group (≥3.3 ng/ml) than in the lower ppTnI group (<3.3 ng/ml): 64% (6%) vs 73% (3%), P = 0.010. In the beating-heart CABG subgroup, multivariable analysis showed that ppTnI exceeding the 80th percentile was a risk factor for overall death (hazard ratio: 1.505, 95% confidence interval: 1.019-2.225, P = 0.040). CONCLUSIONS: Higher ppTnI over the 80th percentile was associated with worse long-term survival in beating-heart CABG, but not in conventional CABG.

Pseudomonas fluorescens imparts cadmium stress tolerance in Arabidopsis thaliana via induction of AtPCR2 gene expression.

BACKGROUND: Cadmium is a non-essential, third largest heavy metal contaminant with long retention time that poses environmental hazards. It emanating majorly from industrial processes and phosphate fertilizers. Cadmium is effortlessly assimilated by plants and leads to yield loss. Henceforth, identification of mechanisms to attenuate the heavy metal toxicity in crops is beneficial for enhanced yields. RESULTS: Beneficial soil bacteria have been known to combat both biotic and abiotic stress, thereby promoting plant growth. Amongst them, Pseudomonas fluorescens has been shown to enhance abiotic stress resistance in umpteen crops for instance maize and groundnut. Here, we investigated the role of P. fluorescens in conferring cadmium stress resistance in Arabidopsis thaliana. In silico analysis of PCR2 gene and promoter revealed the role, in cadmium stress resistance of A. thaliana. Real-time expression analysis employing qRT-PCR ratified the upregulation of AtPCR2 transcript under cadmium stress up to 6 folds. Total leaf (50%), biomass (23%), chlorophyll content (chlorophyll-a and b 40%, and 36 %) silique number (50%), and other growth parameters significantly improved on bacterial treatment of the 2mM Cd-stressed plants. CONCLUSION: Moreover, generated 35s-promoter driven AtPCR2 over-expressing transgenic lines that exhibited resistance to cadmium and other heavy metal stress. Taken together, a crucial interplay of P. fluorscens mediated enhanced expression of AtPCR2 significantly induced cadmium stress resistance in Arabidopsis plants.

Synthetic control of the surface area in nickel cobalt oxide for glucose detection via additive-assisted wet chemical method.

We investigated the effect of specific surface area on the electrochemical properties of NiCo2O4 (NCO) for glucose detection. NCO nanomaterials with controlled specific surface areas were prepared by additive-assisted hydrothermal synthesis, and self-assembled nanostructures with urchin-, pine-needle-, tremella-, and flower-like morphologies were obtained. The novelty of this method is the systematic control of chemical reaction routes assisted by the addition of different additives during synthesis, which results in the spontaneous formation of various morphologies without any difference in the crystal structure and chemical states of the constituent elements. Such morphological control of NCO nanomaterials leads to considerable changes in the electrochemical performance for glucose detection. Combined with materials characterization, the relationship between the specific surface area and the electrochemical performance is discussed for glucose detection. This work can provide scientific insights for tailoring the surface area of nanostructures, which determines their functionality for potential applications in glucose biosensors.

Determination of risk factors associated with surgical site infection in patients undergoing preperitoneal pelvic packing for unstable pelvic fracture.

BACKGROUND: Several recent studies have shown that preperitoneal pelvic packing (PPP) effectively produces hemostasis in patients with unstable pelvic fractures. However, few studies have examined the rate of surgical site infections (SSIs) in patients undergoing PPP following an unstable pelvic fracture. The purpose of the present study was to evaluate factors associated with SSI in such patients. METHODS: We retrospectively reviewed the medical charts of 188 patients who developed hemorrhagic shock due to pelvic fracture between April 2012 and May 2021. Forty-four patients were enrolled in this study. RESULTS: SSI occurred in 15 of 44 patients (34.1%). The SSIs occurred more frequently in cases of repacking during the second-look surgery (0 vs. 4 [26.7%], P=0.010) and combined bladder-urethra injury (1 [3.4%] vs. 4 [26.7%], P=0.039). The incidence of SSIs was not significantly different between patients undergoing depacking within or after 48 hours (12 [41.4%] vs. 5 [33.3%], P=0.603). The mean time to diagnosis of SSI was 8.1±3.9 days from PPP. The most isolated organism was Staphylococcus epidermidis. CONCLUSIONS: Repacking and combined bladder-urethra injury are potential risk factors for SSI in patients with unstable pelvic fracture. Close observation is recommended for up to 8 days in patients with these risk factors. Further, 48 hours after PPP, removing the packed gauze on cessation of bleeding and not performing repacking can help prevent SSI. Additional analyses are necessary with a larger number of patients with the potential risk factors identified in this study.

Ultrasensitive Detection of Fe3+ Ions Using Functionalized Graphene Quantum Dots Fabricated by a One-Step Pulsed Laser Ablation Process.

With respect to the detection of Fe3+ ions, graphene quantum dots (GQDs) have limitations for commercialization owing to their high limit of detection (LOD). Here, we report a one-step pulsed laser ablation (PLA) process to fabricate amino-functionalized GQDs (FGQDs) for the efficient detection of Fe3+ using polypyrrole (PPy) both as a precursor (amine N) and as a surfactant and also using graphite as a carbon precursor. Using this method, the amine N groups were easily incorporated into the carbon network of the GQDs. Additionally, compared to pristine GQDs, FGQDs showed smaller particle sizes and narrower size distributions owing to the surface passivation effects of the PPy surfactant. Due to the synergistic effect of surface passivation and incorporation of amine N groups, FGQDs exhibited a sensitive response to Fe3+ ions in the concentration range of 500 nM to 50 µM, which is lower than the quality standards for Fe3+ ions (∼5.36 µM) as suggested by the World Health Organization (WHO). Furthermore, the processing time for synthesizing FGQDs by the PLA process was less than 30 min, thus allowing successful practical applications of GQDs in the sensing field.

Treatment outcomes of 1-stage clipping of multiple unruptured intracranial aneurysms via keyhole approaches.

OBJECTIVE: Complete exclusion of multiple unruptured intracranial aneurysms (UIAs) in one session of intervention may be ideal. However, such situations are not always feasible in terms of treatment modalities and outcomes. The authors aimed to analyze their experience with 1-stage clipping of multiple UIAs. METHODS: Medical records between March 2013 and December 2018 were retrospectively reviewed, and 111 1-stage keyhole approaches in 110 patients with 261 multiple UIAs were ultimately included in this study. Clinical and radiological outcomes were analyzed, as well as postoperative complications up to 1 month after the surgery and their risk factors. RESULTS: Keyhole approaches included unilateral supraorbital in 87 operations (78.4%), bilateral supraorbital in 12 (10.8%), and others in 12. The mean operative duration was 169.6 minutes (range 80-490 minutes). The highest numbers of aneurysms clipped at once were 2 (73.9%) and 3 (18.9%). Complete exclusion and residual neck of the clipped aneurysms were achieved in 89.3% and 7.3%, respectively. There was no significant difference between pre- and postoperative 1-month neurological states (p = 0.14). The permanent morbidity rate was 1.8% (n = 2), and there were no deaths. Postoperative transient neurological deterioration (TND) with no radiological and electrophysiological abnormalities occurred in 8 operations (7.2%). Hypertension was the only significant risk factor for postoperative TND (adjusted odds ratio 17.03, 95% confidence interval 1.99-2232.24, p = 0.01). CONCLUSIONS: One-stage clipping of multiple UIAs via keyhole approaches showed satisfactory treatment outcomes with a low permanent morbidity. Patients with chronic hypertension had a high risk of postoperative TND.

Methane Gas Cofiring Effects on Combustion and NO x Emission in 550 MW Tangentially Fired Pulverized-Coal Boiler.

A shift from coal to liquefied natural gas for electricity generation can mitigate CO2 emissions and respond to the intermittent and variable characteristics of renewable energy. With this objective, numerical simulation was performed in this study to determine the optimal position of the methane injector and evaluate the achievable reduction in NO x emissions before applying methane cofiring to an existing 550 MW tangentially fired pulverized-coal boiler (Boryeong Unit 3). The combustion and NO x reduction in the furnace were intensively analyzed based on the methane cofiring rate (up to 40%). The optimal position of the methane injector was found to be inside the oil port based on the spatial distribution of NO x and the stoichiometric ratio along the furnace height. The NO x reduction rate was logarithmically proportional to the methane cofiring rate, and compared to the base case, a 69.8% reduction was achieved at the 40% cofiring rate. In addition, the fraction of unburned char at the boiler outlet was equivalent to that of the existing boiler as the increase in the flow rates of the close-coupled and separated overfire air improved fuel and air mixing. Simultaneously, methane cofiring led to a reduction in the total fuel loss and CO emissions. Finally, this study showed that the recommended optimum cofiring rate was 20% based on the furnace exit gas temperature. Under the 20% methane cofiring condition, the boiler achieved a 57.3% reduction in NO x emissions and a 7.4% improvement in fuel loss.

Rescue Strategy for Troublesome Situations Related to Recipient and Donor Arteries During Low-Flow Bypass Surgery.

OBJECTIVE: Although technically demanding, bypass surgery is a vital part of the neurosurgical armamentarium. The aim of this article was to present representative troublesome cases related to the manipulation of donor arteries (DAs) and recipient arteries during low-flow extracranial-intracranial bypass. METHODS: In the past 5 years, 507 low-flow bypass surgeries were performed in patients with cerebral aneurysms, moyamoya disease, and intracranial atherosclerotic stenosis. Frustrating perioperative situations were retrospectively reviewed, and 6 representative cases were described. RESULTS: Case 1 involved repeat microanastomosis owing to occlusion of the anastomotic segment by thrombus formation. Case 2 involved repair of the DA injured by thermal energy. Case 3 involved direct repair of the DA damaged by a sharp knife. Case 4 involved repeat microanastomosis owing to avulsion of the anastomotic segment. Case 5 involved lengthening of the short DA with a nearby interposition graft. Case 6 involved use of retrograde flow via the distal segment of the DA secondary to the injury of the proximal segment of the DA. In all patients, rescue procedures were successful, and bypass flow was patent with no relevant complications. CONCLUSIONS: The intraoperative accidents reported here were frustrating; however, all patients were safely rescued without significant sequelae. It is hoped that our experiences will help young neurosurgeons handle troublesome situations.

Early Experiences with Ultra-Fast-Track Extubation after Surgery for Congenital Heart Disease at a Single Center.

BACKGROUND: Early extubation after cardiovascular surgery has some clinical advantages, including reduced hospitalization costs. Herein, we review the results of ultra-fast-track (UFT) extubation, which refers to extubation performed on the operating table just after the operation, or within 1-2 hours after surgery, in patients with congenital cardiac disease. METHODS: We performed UFT extubation in patients (n=72) with a relatively simple congenital cardiac defect or who underwent a simple operation starting in September 2016. To evaluate the feasibility and effectiveness of our recently introduced UFT extubation strategy, we retrospectively reviewed 195 patients who underwent similar operations for similar diseases from September 2015 to September 2017, including the 1-year periods immediately before and after the introduction of the UFT extubation protocol. Propensity scores were used to assess the effects of UFT extubation on length of stay (LOS) in the intensive care unit (ICU), hospital LOS, and medical costs. RESULTS: After propensity-score matching using logistic regression analysis, 47 patients were matched in each group. The mean ICU LOS (16.3±28.6 [UFT] vs. 28.0±16.8 [non-UFT] hours, p=0.018) was significantly shorter in the UFT group. The total medical costs (182.6±3.5 [UFT] vs. 187.1±55.6 [non-UFT] ×100,000 Korean won [KRW], p=0.639) and hospital stay expenses (48.3±13.6 [UFT] vs. 54.8±29.0 [non-UFT] ×100,000 KRW, p=0.164) did not significantly differ between the groups. CONCLUSION: UFT extubation decreased the ICU LOS and mechanical ventilation time, but was not associated with postoperative hospital LOS or medical expenses in patients with simple congenital cardiac disease.

Comparison of Radiofrequency Ablation and Cryoablation for the Recovery of Atrial Contractility and Survival.

BACKGROUND: Limited comparative data are available on the efficacy of cryoablation versus radiofrequency ablation in patients with atrial fibrillation. This study aimed to compare radiofrequency ablation and cryoablation with regard to clinical outcomes and the restoration of sinus rhythm or atrial contractility. METHODS: A total of 239 patients who underwent surgical ablation between August 2003 and December 2016 at our institution were included. The patients were divided into 2 groups according to the energy device that was used (group A: n=140, radiofrequency ablator; group B: n=99, cryoablator). Echocardiographic data, overall survival, and major cardiovascular and cerebrovascular event (MACCE)-free survival were compared between the 2 groups. RESULTS: At 1 year of follow-up, the atrial contractility recovery rate was 32.2% (19 of 59) in group A and 48.8% (21 of 44) in group B. In addition, cryoablation was found to be a predictive factor for the recovery of atrial contractility (cryoablation vs. radiofrequency ablation: odds ratio, 2.540; 95% confidence interval, 1.063-6.071; p=0.036). The left ventricular ejection fraction was significantly higher in group B (53.1%±11.5% vs. 59.1%±6.3%, p=0.001). The median follow-up duration was 36 months. The 5-year overall survival rate was 80.1%±3.6% in group A and 92.1%±2.9% in group B (p=0.400). The 5-year MACCE-free survival rate was 70.3%±4.0% in group A and 70.9%±5.6% in group B (p=0.818). CONCLUSION: Cryoablation was associated with a higher atrial contractility restoration rate and better left ventricular function than radiofrequency ablation. However, no significant relationship was observed between the energy source and overall or MACCE-free survival.

Clinical significance of the circle of Willis in intracranial atherosclerotic stenosis.

INTRODUCTION: The effectiveness of a scoring system based on the circle of Willis for evaluations of collateral circulation was studied in patients with intracranial atherosclerotic stenosis. METHODS: Eighty-three patients who underwent medical or endovascular treatment for symptomatic and severe intracranial atherosclerotic stenosis were enrolled in the study. Clinical profiles, status of the circle of Willis (poor and good integrity group), and clinical outcomes were analyzed. Primary endpoints were: (1) symptomatic ischemic or hemorrhagic stroke within 30 days; and (2) recurrent transient ischemic attack or ischemic stroke beyond 30 days. RESULTS: The estimated rates of the primary endpoint at 1 and 2 years after treatment were 8.5% and 11.4% in the medical group and 7.0% and 9.7% in the endovascular group, respectively. A primary endpoint event after medical treatment was only identified in patients with poor integrity of the circle of Willis (p=0.059). In patients with poor integrity of the circle of Willis, previous antiplatelet medication before initial presentation (p=0.026) and hypertension (p=0.006) were more prevalent. During the follow-up period, complete arterial occlusion was identified in 9 patients. The circle of Willis score of the patients with complete arterial occlusion was 1.33±1.52 in the fatal stroke group (n=3) and 3.20±1.64 in the asymptomatic group (n=6, p=0.099). CONCLUSIONS: If patients have poor integrity of the circle of Willis, the risk of recurrent stroke may be increased. Such patients appear to be good candidates for endovascular treatment.