Robotic mitral valve surgery

Totally endoscopic robotic mitral valve repair is the least invasive surgical therapy for mitral valve disease. Robotic mitral valve surgery demonstrates faster recovery with shorter hospital stays, less morbidity, and equivalent mortality and mid-term durability compared to sternotomy. In this review, we will explore the advantages and disadvantages of robotic mitral valve surgery and consider important technical details of both operative set-up and mitral valve repair techniques. The number of robotic cardiac surgical procedures being performed globally is expected to continue to rise as experience grows with robotic techniques and increasing numbers of cardiac surgeons become proficient with this innovative technology. This will be facilitated by the introduction of newer robotic systems and increasing patient demand.

Validation of NEWS2, SIRS, and qSOFA in Postoperative Cardiac Patients: A Retrospective Cohort Study

INTRODUCTION

The 'quick Sepsis Related Organ Failure Assessment' (qSOFA), 'Systemic Inflammatory Response Syndrome' (SIRS), and 'National Early Warning Score' 2 (NEWS2) scores are yet to be comparatively validated in ward-based cardiac surgical patients despite widespread routine use in clinical practice. We sought to assess the predictive validity of NEWS, SIRS, and qSOFA in identifying postoperative, ward-level cardiac surgical patients at risk of poor short-term mortality.

METHODS

All adult patients who underwent cardiac surgery at a single tertiary center between November 2014 and October 2017 were identified. Data for bedside observations, hematological results, and microbiology requests were obtained from electronic health records. Survival data were acquired from a national registry. The primary outcome was the discriminatory ability, measured by the area under the receiver operating characteristic (AUROC), of each score for in-hospital mortality.

RESULTS

One thousand five hundred forty three (male n = 1101, 71%) patients were included. Overall in-hospital mortality was 2.4%. There was no significant difference in discriminatory ability of NEWS (AUROC 0.5060), SIRS (AUROC 0.4874), and qSOFA (AUROC 0.5139) for in-hospital mortality (P = 0.881). Sensitivity for this outcome was ubiquitously low (13.51-40.54%).

CONCLUSIONS

Current illness-severity scores show a low discriminatory ability for in-hospital mortality in ward-based cardiac surgical patients. Caution should be used in the application of these prognostic screening tools for early detection of poor outcomes in this population.

Hybrid surgical epicardial cryoablation for ventricular tachycardia in the electrophysiology laboratory: a case report

Background

Scar-related ventricular tachycardia (VT) is a challenging medical condition, with catheter ablation providing a valuable treatment option. Whilst most VTs can be ablated endocardially, epicardial ablation is often required in patients with non-ischaemic cardiomyopathy. The percutaneous subxiphoid technique has become instrumental for epicardial access. However, it is not feasible in up to 28% of cases for multiple reasons.

Case summary

A 47-year-old patient was managed at our centre for VT storm and recurrent implantable cardioverter defibrillator shocks for monomorphic VT despite maximum drug therapy. No scar was noted during endocardial mapping, with confirmation of the localized epicardial scar on cardiac magnetic resonance imaging (CMR). Following failed percutaneous epicardial access, a successful hybrid surgical epicardial VT cryoablation via median sternotomy was performed in the electrophysiology (EP) laboratory utilizing data from CMR, prior endocardial ablation, and conventional EP mapping. The patient has remained arrhythmia-free for 30 months post-ablation without antiarrhythmic therapy.

Discussion

This case describes a practical multidisciplinary approach to managing a challenging clinical problem. Whilst the described technique is not entirely novel, this is the first case report that describes the practicalities and demonstrates the safety and feasibility of hybrid epicardial cryoablation via median sternotomy performed in the cardiac EP laboratory for the sole treatment of VT.

Multiarterial coronary grafting using the radial artery as a second arterial graft: how far does the survival benefit extend?

OBJECTIVES

Despite the 10-year results of the Arterial Revascularization Trial, the controversy regarding the survival benefit of multiarterial grafting (MAG) remains. Our goal was to present our long-term survival data in this propensity-matched observational study.

METHODS

A primary unmatched population of 4303 patients with first-time isolated coronary artery bypass grafts operated on between 2000 and 2018 were included. A total of 1187 post-matched patients were compared with matched controls. Multivariate logistic regression and Cox proportional hazard analyses were undertaken to assess the contribution of MAG and other covariates to the long-term survival of unmatched and propensity-matched populations.

RESULTS

MAG was associated with increased median survival in both the unmatched and the matched groups; difference: 962 and 1459 days, log-rank tests; P = 0.029 and 0.0004, respectively. MAG was associated with a reduced hazard of death in the unmatched as well as in the matched groups: hazard ratio [95% confidence interval (CI)]: 0.72 (0.62-0.83); P < 0.0001 and 0.75 (0.64-0.88); P ≤ 0.0001, respectively. In the matched group, the prosurvival factors were low logistic EuroSCORE, obesity, no intra-aortic balloon pump, an ejection fraction >30%, age 50-69 years, operation by an experienced surgeon, with and without diabetes, on-pump surgery and 3 distal anastomoses. In a cohort of 242 late-presenting patients with reinfarction or recurrent angina, both MAG and control populations were associated with reduced median survival; median (95% CI): MAG: 3026 (1138-3503); control: 3035 (2134-3991), log-rank P = 0.217 with superior patency of the left internal mammary artery but no difference between radial artery and saphenous vein grafts.

CONCLUSIONS

Multiarterial revascularization, especially using the radial artery as a second arterial conduit, is associated with a significant survival benefit and a lack of in-hospital morbidity.

Genomic Analysis of an Indian G8P[1] Caprine Rotavirus-A Strain Revealing Artiodactyl and DS-1-Like Human Multispecies Reassortment

The surveillance studies for the presence of caprine rotavirus A (RVA) are limited in India, and the data for the whole-genome analysis of the caprine RVA is not available. This study describes the whole-genome-based analysis of a caprine rotavirus A strain, RVA/Goat-wt/IND/K-98/2015, from a goat kid in India. The genomic analysis revealed that the caprine RVA strain K-98, possess artiodactyl-like and DS-1 human-like genome constellation G8P[1]-I2-R2-C2-M2-A3-N2-T6-E2-H3. The three structural genes (VP2, VP4, and VP7) were close to caprine host having nucleotide-based identity range between 97.5 and 98.9%. Apart from them, other gene segments showed similarity with either bovine or human like genes, ultimately pointing toward a common evolutionary origin having an artiodactyl-type backbone of strain K-98. Phylogenetically, the various genes of the current study isolate also clustered inside clades comprising Human-Bovine-Caprine isolates from worldwide. The current findings add to the knowledge on caprine rotaviruses and might play a substantial role in designing future vaccines or different alternative strategies combating such infections having public health significance. To the best of our knowledge, this is the first report on the whole-genome characterization of a caprine RVA G8P[1] strain from India. Concerning the complex nature of the K-98 genome, whole-genome analyses of more numbers of RVA strains from different parts of the country are needed to comprehend the genomic nature and genetic diversity among caprine RVA.

Evaluation of sustainability of non-communicable diseases risk factor program in Malaysia

Background

Non-communicable diseases (NCDs) in Malaysia have risen substantially over the last two decades. We aimed to (i) evaluate the sustainability of the existing NCDs risk factor program implemented under the National Strategic Plan and (ii) identify challenges and factors impeding the sustainability of the NCDs program.

Methods

A mixed-method approach using a combination of the Program Sustainability Assessment Tool

with 40-item instrument assessing 8 domains (organizational capacity, program adaptation, program evaluation, communications, strategic planning, funding stability, environmental support and partnerships) and 5 open-ended questions were administered to 80 key managers from district directors of chronic disease programs in Malaysia. The mean score for each of the 8 sustainability domains and the overall mean sustainability score were determined. Data analysis was performed using Statistical Package for the Social Sciences (SPSS) version 25.

Results

Seven domains scored a mean of ≥ 4. The domains of communications (cross-site mean, 4.5 on a scale of 1-7) and organizational capacity (mean, 4.4) had the highest ratings. Funding stability had the lowest rating (mean, 3.8). The overall mean sustainability score was 4.2. Open-ended responses revealed challenges by program leaders, including implementation difficulties, factors impede planning for NCDs sustainability program, lack of financial, staff support and staff training which are largely consistent with the scaled domains.

Conclusions

Capacity issues affecting the sustainability of NCDs program in Malaysia are qualitatively similar to other countries. Future work should aim at improving funding stability and integrating evidence-based public health strategies to sustain implemented NCDs program.

Key messages

Researchers could utilize this tool to assess program design and strategies promoting sustainability during implementation process for long term program sustainment. Investments in leadership support for integrating program evaluation into implementation and greater funding flexibility may enhance sustainability of evidence-based public health program for NCDs.

Incidence of Cirrhotic Cardiomyopathy among Hundred Patients of Tamil Nadu, India- A Cross-sectional Study

Introduction: Cardiac dysfunction in cirrhosis may affect quality of life, prognosis and also may aggravate the course in patients undergoing invasive procedures such as surgery, insertion of a Transjugular Intrahepatic Portosystemic Shunts (TIPS), and liver transplantation. Aim: To evaluate the association of cardiomyopathy in cirrhotic patients of Tamil Nadu region in India. Materials and Methods: This cross-sectional study included 100 diagnosed cirrhotic patients. The patient’s cardiac status was obtained from Electrocardiography (ECG) and echocardiography. Liver profile was obtained from biochemical assays and ultrasonography of abdomen. The patients were classified as per cirrhosis grading system, Child Toucotte Pugh (CTP) scoring. The association was analysed using frequency analysis, percentage analysis and Chi-square test. Results: Prolonged QTc (>0.44 sec) was seen in 35% of the study population (p-value-0.014). A 10% of patients had systolic dysfunction and 25% showed diastolic dysfunction. Also, these patients showed positive troponin T and elevated Brain Natriuretic Peptide (BNP). The incidence of cardiomyopathy in cirrhotic patients was 28% in this study. Conclusion: This study established 28% incidence of cardiomyopathy in cirrhotic patients. This association may further be evaluated in larger study samples to provide a better prognosis and quality of life in cirrhotic patients treated with liver transplantation or other surgical procedures.

Diffusion-weighted MRI assessment of the peritoneal cancer index before cytoreductive surgery

BACKGROUND

Patients with limited peritoneal metastases from colorectal cancer may be candidates for an aggressive surgical approach including cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS-HIPEC). Selection is based on surgical inspection during laparoscopy or laparotomy. The aim of this study was to investigate whether diffusion-weighted MRI (DW-MRI) can be used to select patients for CRS-HIPEC.

METHODS

This was a prospective study at a tertiary referral centre. Patients with confirmed or suspected colorectal peritoneal metastases scheduled for exploratory laparotomy or laparoscopy were eligible. Two radiologists assessed the peritoneal cancer index (PCI) on CT (CT-PCI) and DW-MRI (MRI-PCI). The reference standard was PCI at surgery. Radiologists were blinded to the surgical PCI and to each other's findings. The main outcome was the accuracy of DW-MRI in predicting whether patients had resectable disease (PCI less than 21) or not.

RESULTS

Fifty-six patients were included in the study, of whom 49 could be evaluated. The mean(s.d.) PCI at surgery was 11·27(7·53). The mean MRI-PCI was 10·18(7·07) for reader 1 and 8·59(7·08) for reader 2. Readers 1 and 2 correctly staged 47 of 49 and 44 of 49 patients respectively (accuracy 96 and 90 per cent). Both readers detected all patients with resectable disease with a PCI below 21 at surgery (sensitivity 100 per cent). No patient was overstaged. The intraclass correlation (ICC) between readers was excellent (ICC 0·91, 95 per cent c.i. 0·77 to 0·96). MRI-PCI had a stronger correlation with surgical PCI (ICC 0·83-0·88) than did CT-PCI (ICC 0·39-0·44).

CONCLUSION

DW-MRI is a promising non-invasive tool to guide treatment selection in patients with peritoneal metastases from colorectal cancer.

A 32full factorial design for development and characterization of a nanosponge-based intravaginal in situ gelling system for vulvovaginal candidiasis

The rationale behind present research effort was to enhance CTZ solubility and efficacyviaforming complex with hydroxypropyl β-cyclodextrin (HP-β-CD) nanosponges.

Abstract P6-04-16: TGF-b2, a novel target of CD44-promoted breast cancer invasion

Hyaluronan (HA) mediates communication between cancer cells and the environment via interactions with the cell surface receptor CD44. We have previously shown that CD44-HA interaction in BC cells promotes adhesion to bone marrow endothelial cells. This suggests that HA/CD44 signalling may be correlated with breast cancer (BC) metastasis. The long-term objective of this study is to increase our understanding of the mechanisms by which CD44-HA interaction promotes BC metastasis, and further identify and validate CD44-downstream transcriptional targets for anti-metastatic therapy.

Pursuant to this goal, we have developed a tetracycline (tet)-regulated expression of CD44 gene in the BC cell line MCF-7 (B5 clone) and identified TGF-beta2 (Transforming Growth Factor beta-2; 3 fold induction) as a potential CD44s-downstream transcriptional target by microarray analysis. To further validate this finding, the same RNA samples, used for microarray analysis and their corresponding protein lysates collected from the BC cell line MCF-7-B5, were examined for CD44 expression in the presence of HA for 18, 24, and 48 hr post-tet withdrawal. Expression of TGF-beta 2 was examined using RT-PCR and western-Blot analyses.

Our results showed that TGF-beta2 mRNA levels were significantly elevated following the removal of tet at 18, 24, and 48 h post-HA stimulation compared to the parental cells. Furthermore, the TGF-beta2 precursor protein increased in a time-dependent pattern upon HA-stimulation and in the absence of tet. More interestingly, inhibition of CD44 gene by RNAi method decreased TGF-beta2 expression upon HA-stimulation and in the absence of tet.

Our data strongly support the hypothesis that TGF-beta2 is a potential target of HA/CD44- downstream-signaling mediating BC cell invasion. Ongoing investigation aims to elucidate the signal transduction pathways coupling CD44 to the regulation of TGF-beta2 expression, and further validate CD44/TGF-beta2 axes in breast tumor invasion and metastasis.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P6-04-16.

Performance of submerged membrane bioreactor (SMBR) with and without the addition of the different particle sizes of GAC as suspended medium

In this study the effect of different particle sizes of granular activated carbon (GAC) on the performance of a submerged membrane bioreactor (SMBR) was investigated. The sizes of GAC used were 150-300, 300-600 and 600-1200 μm. The SMBR was operated at a filtration flux of 20 L/m(2)h. The removal of dissolved organic carbon (DOC) and chemical oxygen demand (COD) with the addition of GAC was 95%. The concentration of biopolymers, humic, building block and low molecular weight neutral and acids in the SMBR effluent was reduced by 20%, 66-76%, 20-50%, 30-56%, respectively. It helped to reduce the sludge volume index (SVI) and transmembrane pressure (TMP) development by 30-40% and 58%, respectively. However, the removal of NH₄(+) and PO₄(3-) was relatively low of 35-45% and 34-43%, respectively. The SMBR effluent was rich in PO₄(3-) and was removed/recovered using hydrated ferric oxide (HFO). The removal of PO₄(3-) was almost 90%.

Abstract P4-06-16: TGF-β2, A Novel Target of CD44-Promoted Breast Cancer Invasion

Background: Hyaluronan (HA) mediates communication between cancer cells and the environment via interactions with the cell surface receptor CD44. We have previously shown that CD44-HA interaction in BC cells promotes adhesion to bone marrow endothelial cells. This suggests that HA/CD44 signalling may be correlated with breast cancer (BC) metastasis. The long-term objective of this study is to increase our understanding of the mechanisms by which CD44-HA interaction promotes BC metastasis, and further identify and validate CD44-downstream transcriptional targets for anti-metastatic therapy.

Materials & Methods: Pursuant to this goal, we have developed a tetracycline (tet)-regulated expression of CD44 gene in the BC cell line MCF-7 (B5 clone) and identified TGF-β2 (Transforming Growth Factor beta-2; 3 fold induction) as a potential CD44s-downstream transcriptional target by microarray analysis. To further validate this finding, the same RNA samples, used for microarray analysis and their corresponding protein lysates collected from the BC cell line MCF-7-B5, were examined for CD44 expression in the presence of HA for 18, 24, and 48 hr post-tet withdrawal. Expression of TGF-β2 was examined using RT-PCR and western-Blot analyses.

Results: Our results showed that TGF-β2 mRNA levels were significantly elevated following the removal of tet at 18, 24, and 48 h post-HA stimulation compared to the parental cells. Furthermore, the TGF-β2 precursor protein increased in a time-dependent pattern upon HA-stimulation and in the absence of tet. More interestingly, inhibition of CD44 gene by RNAi method decreased TGF-β2 expression upon HA-stimulation and in the absence of tet.

Conclusion: Our data strongly support the hypothesis that TGF-β2 is a potential target of HA/CD44- downstream-signaling mediating BC cell invasion. Ongoing investigation aims to elucidate the signal transduction pathways coupling CD44 to the regulation of TGF-β2 expression, and further validate CD44/TGF-β2 axes in breast tumor invasion and metastasis.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P4-06-16.

Abstract P4-06-14: CD146-suppresses breast tumor invasion via a novel transcription target TIMPv

The function of the cell adhesion receptor CD146, a recently discovered marker of endothelial cells and a tumor promoter of melanoma and other cancers, is controversial in breast cancer (BC). However several lines of evidence supports its role as a tumor suppressor in BC. Further, the molecular mechanisms underpinning this suppression are unknown, neither has the ligand for CD146 been identified. Using a novel validated Enhanced Green Fluorescent Protein (EGFP)-inducible systems of CD146 expression both in vitro and in vivo, we provide here molecular and functional evidence of CD146 and its novel transcriptional target TIMPv (a variant of tissue inhibitor of metallo-proteinases) in underpinning the suppression of BC invasion.

Tetracycline (tet-on) CD146 system was developed in both MCF-7 and MDA-231 BC founder cell lines, and validated using time course RT-PCR and western blot analyses, and fluorescent microscopy. In functional experiments, induction of CD146 inhibited BC cell migration and invasion. TIMPv, the only endogenous protein inhibitor known for metallocarboxypeptidases, was identified by expression profiling as a novel transcriptional target of CD146-signaling, an association validated by quantitative PCR and immunoblotting experiments in a range of breast and melanoma cancer cells. However, siRNA inhibition of CD146 in the SKMel-28 melanoma cell line increased TIMPv expression, suggesting that while TIMPv is a positive transcriptional target of CD146 in BC cells, it is negatively regulated in melanoma cells. Furthermore, using invasion assay, the functional relevance of TIMPv to CD146-suppressed metastasis was demonstrated by selective suppression of TIMPv in CD146-expressing BC inducible cells using RNAi. More interestingly, induction of CD146 expression in vivo, using the tet-on CD146 expression system in BC Xenograft model resulted in suppression of breast tumor growth. Further, Clinical analysis of breast tissue samples by Immunohistochemistry showed that TIMPv expression patterns paralleled those of CD44s during breast tumor progression. Pharmacological and molecular approaches revealed that the activation of NFκB via Akt pathway couples CD146 to the transcription of TIMPv in BC cells.

Our study is the first report to provide a functional molecular link of a novel transcriptional target of CD146, TIMPv, to cancer via a unique axis that underpin CD146-suppressed BC progression; TIMPv is a potential target for guiding the development of novel therapeutic strategies for BC.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P4-06-14.

Formulation and Evaluation of Hydroxypropyl Methylcellulose-based Controlled Release Matrix Tablets for Theophylline

The objectives of the study were to formulate hydroxypropyl methyl cellulose-based controlled release matrix tablets for theophylline with varying drug:polymer ratios (1:1 and 1:2) and differing tablet hardness (5, 6 and 7 kg/cm(2)), and to evaluate the tablet's physico-chemical properties such as hardness, uniformity of weight, friability, drug content and in vitro drug release. Initially, granules were made by wet granulation technique and evaluated for angle of repose, bulk density, tapped density, bulkiness, compressibility index and hausner ratio. The results indicate good flow property of the granules and thus, the evaluated tablet physical properties were within the acceptable limits. The FT-IR study for the F-6 formulation showed that there was no interaction between the drug and the polymer. In vitro release studies were performed using Disso-2000 (paddle method) in 900 ml of pH 7.4 at 50 rpm. The result indicated that at high drug:polymer ratio (1:2) and hardness value 7 kg/cm(2), prolonged drug release was observed than the low drug: polymer ratio (1:1) and hardness values (5 and 6 kg/cm(2)). The release kinetics was found to follow korsmeyers-peppas model and the mechanism of drug release was by non-fickian or anomalous diffusion. The F-6 formulation was chosen for stability studies. F-6 formulation was stable when it was kept at different temperatures for a period of 6 months.

Mitochondrial permeability transition pore as a target for cardioprotection in the human heart

After an episode of myocardial ischemia, opening of the mitochondrial permeability transition pore (mPTP), at the onset of reperfusion, is a critical determinant of myocyte death. We investigated the role of the mPTP as a target for cardioprotection in the human heart. We subjected human atrial tissue, harvested from patients undergoing cardiac surgery, to a period of lethal hypoxia and investigated the effect of suppressing mPTP opening at the onset of reoxygenation. We found that suppressing mPTP opening at the onset of reoxygenation with known mPTP inhibitors cyclosporin A (CsA, 0.2 micromol/l) and sanglifehrin A (SfA, 1.0 micromol/l) 1) improved recovery of baseline contractile function from 29.4 +/- 2.0% under control conditions to 48.7 +/- 2.2% with CsA and 46.1 +/- 2.3% with SfA (P < 0.01) and 2) improved cell survival from 62.8 +/- 5.3% under hypoxic control conditions to 91.4 +/- 4.1% with CsA and 87.2 +/- 6.2% with SfA (P < 0.001). Furthermore, with a cell model in which oxidative stress was used to induce mPTP opening in human atrial myocytes, we demonstrated directly that CsA and SfA mediated their cardioprotective effects by inhibiting mPTP opening, as evidenced by an extension in the time required to induce mPTP opening from 116 +/- 8 s under control conditions to 189 +/- 10 s with CsA and 183 +/- 12 s with SfA (P < 0.01). We report that suppressing mPTP opening at the onset of reoxygenation protects human myocardium against lethal hypoxia-reoxygenation injury. This suggests that, in the human heart, the mPTP is a viable target for cardioprotection.

A fluorescent Gram stain for flow cytometry and epifluorescence microscopy

The fluorescent nucleic acid binding dyes hexidium iodide (HI) and SYTO 13 were used in combination as a Gram stain for unfixed organisms in suspension. HI penetrated gram-positive but not gram-negative organisms, whereas SYTO 13 penetrated both. When the dyes were used together, gram-negative organisms were rendered green fluorescent by SYTO 13; conversely, gram-positive organisms were rendered red-orange fluorescent by HI, which simultaneously quenched SYTO 13 green fluorescence. The technique correctly predicted the Gram status of 45 strains of clinically relevant organisms, including several known to be gram variable. In addition, representative strains of gram-positive anaerobic organisms, normally decolorized during the traditional Gram stain procedure, were classified correctly by this method.

Mapping of the cellular immune responses to woodchuck hepatitis core antigen epitopes in chronically infected woodchucks

T-cell responses to hepatitis B virus nucleocapsid antigens (HBcAg and HBeAg) play an important role in disease outcome in those infected with hepatitis B virus (HBV). The woodchuck is naturally infected in the wild with woodchuck hepatitis virus (WHV), which shows a high degree of genetic homology to HBV and produces a similar pattern of infection in its natural host. Twenty-three overlapping peptides were constructed to cover the entire WHV core region and used to identify immunodominant cellular epitopes in the nucleocapsid antigen using peripheral blood lymphocytes from 12 chronic WHV carrier and 4 uninfected control animals. A peripheral blood lymphocyte response was seen in all of the chronic WHV carrier animals to at least one peptide, and in 8 of the 12 chronic carrier animals a response was observed to 5 common peptides: peptide analogues of amino acids 16-30, 38-52, 50-69, 76-90 and 91-105. Peptide 91-105 produced maximal proliferation in 5 out of 12 infected animals. In addition, a difference in response was observed between wild and laboratory infected animals; the latter appeared to have a lower response to peptides than animals infected in the wild. This study provides evidence that the woodchuck has a population of peripheral blood cells which are sensitised to epitopes within the nucleocapsid protein and provides a basis on which to develop the use of the woodchuck as an immunological model of HBV infection for testing therapeutic means of enhancing this response.