Spontaneous ventilation video-assisted thoracic surgery for mediastinal tumor resection in patients with pulmonary function deficiency

BACKGROUND

Whether non-intubated spontaneous ventilation video-assisted thoracoscopic surgery (SV-VATS) is a safe procedure remains controversial for mediastinal tumor patients with impaired lung function. Herein, we assessed feasibility of SV-VATS in lung function deficiency patients underwent mediastinal tumor resection.

METHODS

From December 2015 to February 2020, 32 mediastinal tumor patients with impaired lung function (preoperative forced expiratory volume in 1 second <70% of the predicted value) were retrospectively collected. Patients were divided into two groups: SV-VATS group and mechanical ventilation VATS (MV-VATS) group. Intraoperative and postoperative variables were compared between two cohorts.

RESULTS

Fifteen patients (46.88%) underwent SV-VATS and 17 patients (53.12%) were performed with MV-VATS. The most common causes of lung function deficiency were smoking (81.25%) and COPD (71.88%). Patients in the SV-VATS group had similar blood loss (20.63 vs. 18.76 mL, P=0.417) with MV-VATS group. The anesthesia time (217.51 vs. 197.76 min; P=0.343) and surgery time (141.23 vs. 132.36 min; P=0.209) were also similar between groups. Five people suffered postoperative complications in each group, in which 1 patient underwent MV-VATS was transferred to intensive care unit (ICU) because of prolonged extubation owing to hypoxia. There was no difference on chest tube removal time (2.6 vs. 2.3 days; P=0.172) or hospital duration (5.03 vs. 4.74 days; P=0.297) in patients underwent SV-VATS and MV-VATS.

CONCLUSIONS

SV-VATS is safe and provides similar short-term results to MV-VATS for mediastinal tumor resection in patients with limited pulmonary function.

Decreased right ventricular strain before LVAD implantation is associated with adverse early outcome

Objectives

Right ventricular (RV) failure occurring after left ventricular assist device (LVAD) implantation is associated with increased mortality.

Purpose

We sought to determine whether RV strain by echocardiography predicts outcomes following LVAD.

Methods

Consecutive patients who underwent continuous flow LVAD placement at our clinic between February 2007 and October 2018 were included. Patients with complex congenital heart disease and arrhythmogenic right ventricular cardiomyopathy were excluded. Baseline characteristics, pre-operative hemodynamic catheterization (1 week) transthoracic echocardiography (1 month) measurements were obtained from the medical record. Speckle tracking RV free wall longitudinal 2D strain was measured using TomTec Imaging System. Univariate and multivariable analysis performed to identify predictors of mortality following LVAD.

Results

The study group was comprised of 323 patients (mean age 60.8±11.5, 79.9% male) of which 256 had adequate image quality for RV strain. RV strain was impaired in most patients (mean −11.7±3.47). RV strain of −8.1% was identified as predictive of poor outcomes. RV strain did not correlate with other measures of RV dysfunction including pulmonary artery pulsatility index (PAPi) and RVFAC. After adjusting for PAPi, RA pressure, and clinical cumulative risk scores (Matthews, Kormos and Lietz-Miller) impaired RV free wall longitudinal strain (OR: 1.14; 95% CI: 1.01–1.29, p=0.025), tricuspid regurgitation (by vena contracta width (TRvc) (OR: 1.19; 95% CI: 1.05–1.36, p=:0.0021) and smaller LVEDD (OR: 0.95; 95% CI: 0.92–0.99, p:0.023) predicted 30-day all-cause mortality and RV failure. Decreased RV free wall strain also predicted peri-operative mortality (22.58% vs. 4.89%, p=0.0003) and prolonged inotropic support (247.0.±277.4 vs. 122.8±139.3, p=0.024).

Conclusions

RV free wall strain is a non-invasive independent predictor of 30-day adverse outcomes (RV failure or all-cause mortality) Routine measurement of RV free strain may identify those patients at highest risk for early and long term mortality following LVAD.

Funding Acknowledgement

Type of funding source: None

Prognostic utility of cardiopulmonary exercise testing indices in arrhythmogenic right ventricular cardiomyopathy

Introduction

Cardiopulmonary exercise testing (CPET) has an established role in the clinical evaluation of exercise intolerance and in the risk stratification of patients with heart failure. There is limited data assessing its prognostic utility in the evaluation of patients with Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC). The predisposition of patients with ARVC for ventricular arrhythmias and sudden cardiac death has led to recommendations for exercise restrictions and limits our understanding of how the impairment in oxygen extraction and cardiac output impact disease progression and outcomes in these patients.

Purpose

We examined the association between CPET indices and event free survival (time to mortality or cardiac transplantation) in patients with Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC).

Methods

Patients with definite ARVC based on 2010 task force criteria and genetically positive were enrolled into our institutional ARVC registry. 43 patients underwent CPET and have been included in our analyses. Indications for testing included: Evaluation of exercise-induced palpitations/arrhythmias or syncope (37%), pharmacotherapy optimization (28%), heart failure evaluation (19%), and ARVC management decisions (16%). CPET data (peak oxygen consumption (pVO2), respiratory exchange ratio (RER), and ventilatory efficiency (VE/VCO2) were assessed in patients at time of initial evaluation. Median follow-up time was 4.9 years (IQR 9 years).

Results

126 patients were studied (age 43.7+ 15 yrs; 41% women; LVEF 57+ 11%; 15% with LVEF &lt;50%) and 43 underwent CPET evaluation. 41 patients (95%) performed at near maximal effort (RER &gt;1) and no fatal events were reported during testing. During the follow up period, the outcome (death or cardiac transplantation) occurred in 31 patients. On Kaplan Meier analysis, pVO2 ≤14 mL/kg/min was associated with worse outcomes (unadjusted p&lt;0.001). Peak oxygen consumption (pVO2) ≤14 mL/kg/min and ventilatory efficiency (VE/VCO2) &gt;34 were associated with shorter event free survival (HR 5.58, p=0.002 and HR 5.56 p=0.005, respectively). After adjusting for age, sex, and right ventricular function, the association between peak oxygen consumption (pVO2) and event free survival remained significant (p=0.02).

Conclusions

In patients with ARVC, peak oxygen consumption (pVO2) was a prognostic indicator of worse outcomes. Our findings suggest a potential role for pVO2 in disease surveillance and early assessment for advanced heart failure therapies.

Figure 1. KM plot pVO2 & event free survival

Funding Acknowledgement

Type of funding source: Other. Main funding source(s): Mayo Clinic

Influence of different crosslinking mixtures on the mechanical properties of composite solid rocket propellants based on HTPB

The crosslinking agent is a vital key which affects the mechanical properties of composite solid rocket propellants (CSRPs). Under this scheme, the effect of crosslinking mixtures (CMs) based on trimethylolpropane (TMP) as a triol crosslinker and butanediol (BD) as a chain extender on CSRPs based on hydroxyl-terminated polybutadiene was investigated. A series of 27 propellant compositions was formulated to study the mechanical properties of the prepared CSRPs. The effect of changing the weight ratio of TMP to BD in the CM was studied. In addition, the influence of increasing the percentage of CM (from 0% to 0.5%) in the prepared samples was investigated. Also, the effect of the CM on CSRPs containing different curing ratio of NCO/OH = 0.7, 0.75, and 0.8 was studied to generate the largest possible strain-ability with high strength over different levels of curing conditions. The mechanical characteristics (tensile strength and strain) of the prepared CSRPs have been measured and plotted versus CM content, NCO/OH and TMP:BD ratio. Generally, the addition of CM leads to a remarkable enhancement in the propellant mechanical properties. Samples containing TMP:BD (2:1) provide the highest strength while samples containing TMP:BD (1:2) show the highest strain over all the NCO/OH ratios. Formulations with TMP:BD (1:1) give high strength with moderate strain. Variation in CM content has a remarkable influence on the mechanical properties of CSRPs. A wide range of tensile strength and strain were obtained from this study to offer variety of results suitable for different applications in the CSRPs technology.

Endosperm enrichment and physicochemical properties of superior and inferior grain starch in super hybrid rice

A significant asynchronous phenomenon exists in super hybrid rice because of the differences in spike and spikelet positions, which affect the accumulation and properties of starch. However, little is known about the endosperm enrichment and physicochemical properties of starch in superior and inferior grains in super hybrid rice. Rice YY2640 was selected as study material to investigate the enrichment and physicochemical properties of starch in superior and inferior grains in super rice using semi-thin sections, X-ray diffraction and related technologies. Superior grain filling was a continuous process, whereas inferior grain only started 8-10 days after anthesis. The order of starch accumulation starts in the central endosperm, then in the endosperm of the proximal vascular bundle and finally in the aleurone layer. Compared with the inferior grains, the superior grains have a higher 1000-grain weight, apparent amylose content, total starch content, average starch granule size, relative crystallinity, solubility and a resonance peak ratio at 1022/995 cm^-1 , whereas the swelling power and ratio of the resonance peak at 1045/1022 cm^-1 were lower. The final degree of hydrolysis of HCl, AAG and PPA of the superior grains were significantly lower than those of the inferior grains. The findings indicate that the different physicochemical properties of starch were mainly related to the development order of superior and inferior grains and the spatial enrichment of starch.

Serum STIP1, a Novel Indicator for Microvascular Invasion, Predicts Outcomes and Treatment Response in Hepatocellular Carcinoma

Background: Previous studies reported that stress-induced phosphoprotein 1 (STIP1) can be secreted by hepatocellular carcinoma (HCC) cells and is increased in the serum of HCC patients. However, the therapy-monitoring and prognostic value of serum STIP1 in HCC remains unclear. Here, we aimed to systemically explore the prognostic significance of serum STIP1 in HCC.

Methods: A total of 340 HCC patients were recruited to this study; 161 underwent curative resection and 179 underwent transcatheter arterial chemoembolization (TACE). Serum STIP1 was detected by enzyme-linked immunosorbent assay (ELISA). Optimal cutoff values for serum STIP1 in resection and TACE groups were determined by receiver operating characteristic (ROC) analysis. Prognostic value was assessed by Kaplan-Meier, log-rank, and Cox regression analyses. Predictive values of STIP1 for objective response (OR) to TACE and MVI were evaluated by ROC curves and logistic regression.

Results: Serum STIP1 was significantly increased in HCC patients when compared with chronic hepatitis B patients or health donors (both P < 0.05). Optimal cutoff values for STIP1 in resection and TACE groups were 83.43 and 112.06 ng/ml, respectively. High pretreatment STIP1 was identified as an independent prognosticator. Dynamic changes in high STIP1 status were significantly associated with long-term prognosis, regardless of treatment approaches. Moreover, post-TACE STIP1 was identified as an independent predictor for OR, with a higher area under ROC curve (AUC-ROC) than other clinicopathological features. Specifically, pretreatment STIP1 was significantly increased in patients with microvascular invasion (MVI), and was confirmed as a novel, powerful predictor for MVI.

Conclusions: Serum STIP1 is a promising biomarker for outcome evaluation, therapeutic response assessment, and MVI prediction in HCC. Integration serum STIP1 detection into HCC management might facilitate early clinical decision making to improve the prognosis of HCC.

Spreading Speed in an Integrodifference Predator-Prey System without Comparison Principle

In this paper, we study the spreading speed in an integrodifference system which models invasion of predators into the habitat of the prey. Without the requirement of comparison principle, we construct several auxiliary integrodifference equations and use the results of monotone scalar equations to estimate the spreading speed of the invading predators. We also present some numerical simulations to support our theoretical results and demonstrate that the integrodifference predator-prey system exhibits very complex dynamics. Our theory and numerical results imply that the invasion of predators may have a rough constant speed. Moreover, our numerical simulations indicate that the spatial contact of individuals and the overcompensatory phenomenon of the prey may be conducive to the persistence of nonmonotone biological systems and lead to instability of the predator-free state.

Feasibility and safety of PD-1/L1 inhibitors for non-small cell lung cancer in front-line treatment: a Bayesian network meta-analysis

Background

This Bayesian network meta-analysis (NMA) was conducted to compare efficacy and safety of programmed death 1/ligand 1 (PD-1/L1) inhibitors in previous untreated advanced non-small cell lung cancer (NSCLC) patients.

Methods

Eligible studies evaluating first-line anti-PD-1/L1 based regimens in advanced NSCLC patients were included. Overall survival (OS), progression free survival (PFS), objective response rate (ORR), as well as treatment-related severe adverse events (tr-SAE) were synthesized within the Bayesian framework. Subgroup analysis was conducted according to PD-L1 expression.

Results

Twelve studies including 7,490 patients and 9 treatment strategies were enrolled in this study. For the PD-L1 expression non-selective patients, all chemo-immunotherapies were significantly better than chemotherapy for prolonging OS and PFS, except for caremlizumab plus chemotherapy (HR =0.72) failed to show advantages for OS. In addition, pembrolizumab plus chemotherapy showed better PFS than nivolumab plus ipilimumab (HR =0.66). In PD-L1 ≥50% patients, all immunotherapy was better than chemotherapy for OS, except for nivolumab (HR =0.83) and nivolumab plus ipilimumab (HR =0.70). For PFS, pembrolizumab plus chemotherapy (HR =0.39), atezolizumab plus chemotherapy (HR =0.47) and pembrolizumab (HR =0.67) were significantly better than chemotherapy. In PD-L1 1–49% patients, pembrolizumab plus chemotherapy (HR =0.52) and atezolizumab plus chemotherapy (HR =0.70) were better than chemotherapy for PFS. In the PD-L1 positive or negative group, all included corresponding regimens were equivalence according to OS and PFS.

Conclusions

We conducted a systematic comparison of first line immunotherapy for advanced NSCLC. Chemo-immunotherapies were better than chemotherapy and mono-immunotherapies in most patients. Pembrolizumab might have better efficacy than other PD-1/L1 inhibitors.

Genomic origin and EGFR-TKI treatments of pulmonary adenosquamous carcinoma

BACKGROUND

Adenosquamous carcinoma (ASC) of the lung is a heterogeneous disease that is composed of both adenocarcinoma components (ACC) and squamous cell carcinoma components (SCCC). Their genomic profile, genetic origin, and clinical management remain controversial.

PATIENTS AND METHODS

Resected ASC and metastatic tumor in regional lymph nodes (LNs) were collected. The ACC and SCCC were separated by microdissection of primary tumor. The 1021 cancer-related genes were evaluated by next-generation sequencing independently in ACC and SCCC and LNs. Shared and private alterations in the two components were investigated. In addition, genomic profiles of independent cohorts of adenocarcinomas and squamous cell carcinomas were examined for comparison. We have also carried out a retrospective study of ASCs with known EGFR mutation status from 11 hospitals in China for their clinical outcomes.

RESULTS

The most frequent alterations in 28 surgically resected ASCs include EGFR (79%), TP53 (68%), MAP3K1 (14%) mutations, EGFR amplifications (32%), and MDM2 amplifications (18%). Twenty-seven patients (96%) had shared variations between ACC and SCCC, and pure SCCC metastases were not found in metastatic LNs among these patients. Only one patient with geographically separated ACC and SCCC had no shared mutations. Inter-component heterogeneity was a common genetic event of ACC and SCCC. The genomic profile of ASC was similar to that of 170 adenocarcinomas, but different from that of 62 squamous cell carcinomas. The incidence of EGFR mutations in the retrospective analysis of 517 ASCs was 51.8%. Among the 129 EGFR-positive patients who received EGFR-TKIs, the objective response rate was 56.6% and the median progression-free survival was 10.1 months (95% confidence interval: 9.0-11.2).

CONCLUSIONS

The ACC and SCCC share a monoclonal origin, a majority with genetically inter-component heterogeneity. ASC may represent a subtype of adenocarcinoma with EGFR mutation being the most common genomic anomaly and sharing similar efficacy to EGFR TKI.

Organic trace minerals improve eggshell quality by improving the eggshell ultrastructure of laying hens during the late laying period

The objective of this study was to investigate the effects of low inclusion levels of organic trace minerals (iron, copper, manganese, and zinc) on performance, eggshell quality, serum hormone levels, and enzyme activities of laying hens during the late laying period. A total of 405 healthy hens (HY-Line White, 50-week-old) were randomly divided into 3 treatments, with 9 replications per treatment and 15 birds per replication. The dietary treatments included a basal diet supplemented with inorganic trace minerals at commercial levels (CON), a basal diet supplemented with inorganic trace minerals at 1/3 commercial levels (ITM), and a basal diet supplemented with proteinated trace minerals at 1/3 commercial levels (TRT). The trial lasted 56 D (8 wk). Compared with the CON group, the ITM group showed decrease in (P < 0.05) egg production, eggshell strength, eggshell palisade layer, palisade layer ratio, serum estrogen, luteinizing hormone, glycosaminoglycan concentration, and carbonic anhydrase activity and increase in (P < 0.05) egg loss and mammillary layer ratio. However, the TRT group almost kept all the indices close to the CON group (P > 0.05). Furthermore, hens fed with low inclusion levels of organic trace minerals had smaller mammillary knobs (P < 0.05) than those in the CON and ITM groups. In conclusion, hens fed with low inclusion levels of proteinated trace minerals had better performance and eggshell strength than those fed with identical levels of inorganic compounds; organic trace minerals improved eggshell quality by improving the eggshell ultrastructure of laying hens during the late laying period.

P5717Risk of QTC interval prolongation among cancer patients treated with tyrosine kinase inhibitors

Objective

QTc interval prolongation can lead to life-threatening complications such as torsade de pointes (TdP), ventricular tachycardia (VT), and sudden cardiac death (SCD). It can occur with various tyrosine kinase inhibitors (TKIs) but comparative analyses on the incidence and complication rates are scarce. We thus conducted a comprehensive analysis of TKI use and QTc prolongation in clinical practice.

Methods

We retrospectively reviewed the electronic medical records of all cancer patients who were treated with TKI between 01/2005 and 12/2018 at our institution. QTc prolongation was defined as a QTc ≥450 ms or 460 ms among male or female patients, respectively. For each type of TKIs, we determined the administration rate and incidence of QTc interval prolongation. We also studied the frequency of QTc prolongation ≥500 ms, the rate of increase of the QTc interval by ≥60 ms, and the development of complications (VT, TdP, and SCD).

Results

In the present study, we analyzed the data of 685 cancer patients (431 male and 254 female), including 299 patients with RCC, 188 with chronic leukemia, 55 with acute leukemia, 65 with thyroid cancer, 48 with lung cancer and 39 with GIST. These patients received 902 TKI administrations and QTc prolongation was reported in 1/3 of these (289 administrations). The highest frequency was seen with imatinib, nilotinib, and dasatinib (30, 40 and 50%). Among cases of QTc prolongation, a QTc interval ≥500 ms was documented in 53 (18.3%) and QTc progression ≥60 ms in 72 (25%). Complications were found in 14 cases (5%) including VT in 9, TdP in 2 and SCD in 3 administrations. Table 1 demonstrates the findings for each TKI.

Findings for TKIs in all patients Total Prolonged QTc QTc ≥500 QTc progression ≥60 VT SCD TdP Imatinib 165 54 13 10 2 Nilotinib 75 33 8 19 Dasatinib 115 58 10 16 2 1 Sunitinib 134 31 1 2 1 1 Pazopanib 165 36 5 6 2 1 Others 248 77 16 18 2 1 1

Conclusion

The current findings suggest that TKI therapy leads to QTc prolongation in 1/3 of patients on average and most commonly with the Bcr-Abl TKIs, imatinib, nilotinib, and dasatinib. While SCD is rare (1%) it can still evolve and in 5% of all QTc prolongations with TKIs are potentially life-threatening. These data support recommendations for serial ECGs in cancer patients undergoing TKI therapy.

Acknowledgement/Funding

None

P2601Trans-catheter or surgical mitral valve procedure versus conservative treatment in heart failure patients with preserved ejection fraction

Background

Secondary mitral regurgitation (SMR) impacts outcomes in heart failure with reduced ejection fraction (HFrEF) but whether it is a specific therapeutic target in heart failure patients with preserved ejection fraction (HFpEF) is less clear.

Purpose

The aims of this study were to investigate whether surgical or trans-catheter intervention reduces SMR and improves outcomes compared to optimal medical therapy in HFpEF patients.

Methods

We retrospectively identified 120 HFpEF patients with moderate-to-severe or greater SMR from January 1, 2007, until December 31, 2017. Moderate-to-severe SMR was defined as an effective regurgitant orifice area of >0.3cm2, and/or a regurgitation volume of >45ml per beat. Those with primary mitral regurgitation, endocarditis, HFrEF, hypertrophic cardiomyopathy, congenital heart disease, and history of valve intervention were excluded. All-cause mortality was analyzed and correlated to clinical and echocardiographic characteristics. Amongst the 120 patients, 36 received surgical or trans-catheter procedure in addition to medical therapy (procedure group) and 84 patients received optimal medical therapy only (conservative treatment group). The median follow-up period was 864 (15–3553) days.

Results

Patients in the procedure group were younger (75±8 vs 81±10, P=0.0002) and with fewer comorbidities (Charlson Comorbidity Index 7.0±2.4 vs 8.0±2.0, P=0.022) compared to the conservative treatment group. In addition, the procedure group had larger left ventricular end-diastolic diameters and higher SMR volume at baseline. During follow-up, SMR decreased by ≥2 grades in 75% of patients (27/36) in the procedure group compared to 20% of patients (12/60) in the conservative treatment group. After adjusting for age and comorbidities, the procedure group showed better overall survival compared to the conservative treatment group (HR 0.37; 95% CI 0.17–0.80; P=0.011). On multivariate analysis for the different groups (procedure group vs. conservative treatment group) (HR 0.40; 95% CI 0.17–0.91; P=0.019), increasing Charlson Comorbidity Index (HR 1.16; 95% CI 1.02–1.32; P=0.028) and average mitral E/e' ratio (HR 1.06; 95% CI 1.01–1.11; P=0.031) were independent predictors of increased all-cause mortality.

Kaplan-Meier Survival Curve

Conclusion

Among heart failure patients with preserved ejection fraction and moderate-to-severe or severe SMR, surgical or trans-catheter mitral-valve repair or replacement resulted in lower all-cause mortality compared to conservative treatment after 9 years of follow-up.

Spreading speeds of epidemic models with nonlocal delays

We estimate the spreading speeds in diffusive epidemic models with nonlocal delays, nonlinear incidence rate and constant recruitment rate. The purpose is to model the process that the infective invades the habitat of the susceptible, and they coexist eventually. In order to focus on our idea, a system with a nonlinear incidence rate is firstly studied, which implies a saturation level of the infective individuals and monotone incidence rate. When the initial value of the infective has nonempty compact support, we prove the rough spreading speed that equals the minimal wave speed of traveling wave solutions in the known results. Then for a general (nonmonotone) incidence rate, we obtain the spreading speeds by constructing auxiliary systems admitting a monotone incidence rate, and prove the convergence of solutions on any compact spatial interval. Furthermore, some numerical examples are given to estimate the invasion speed and show the nontrivial effect of time delay and spatial nonlocality, which implies that the stronger spatial nonlocality leads to larger spreading speeds.