Novel Epicardial Access Technique Facilitated by Carbon Dioxide Insufflation of the Pericardium for Ablation of Ventricular Arrhythmias: Lessons From the Early Experience From a Single Centre in Australia

INTRODUCTION

Epicardial access for mapping and ablation of the epicardial substrate may be required in catheter ablation of ventricular tachycardias (VT). However, high complication rates are associated with the standard epicardial access approach. Recently, a novel method of intentional coronary vein (CV) exit with pericardial CO₂ insufflation to facilitate epicardial access has been described. This study describes our initial experience with this technique.

METHODS

Patients undergoing epicardial VT ablation between 1 February 2021 to 31 May 2022 at the Royal Prince Alfred Hospital, Sydney, NSW, were included in this study. Via femoral venous access, a branch of the coronary sinus was sub-selected and intentional CV exit was performed with a high tip load coronary angioplasty wire. A microcatheter was then advanced over the wire into the pericardial space, followed by pericardial CO₂ insufflation, facilitating subxiphoid pericardial puncture.

RESULTS

Five (5) patients underwent epicardial access for VT mapping and ablation. All patients had successful intentional CV exit and CO₂ facilitated epicardial access. The mean time to successful epicardial access was 37.2±17.5 minutes. With increasing operator experience, there was improvement in epicardial access times, with the fifth case requiring only 13 minutes. There was one case of inadvertent right ventricular puncture (without haemodynamic or ventilatory compromise) due to inappropriate CO₂ insufflation into the right ventricle. Epicardial access was successful on the second attempt.

CONCLUSION

This is the first case series of epicardial access facilitated by CO₂ insufflation in Australia. This technique enabled successful epicardial access in all patients in our early experience, with no adverse outcomes from epicardial access. With increasing operator experience, this technique may allow for more widespread adoption of up-front epicardial access for the treatment of VT.

Reconstructed meta-analysis of percutaneous coronary intervention versus coronary artery bypass grafting for left main disease

Background

Randomized controlled trials (RCTs) comparing percutaneous coronary intervention (PCI) with drug-eluting stents and coronary artery bypass grafting (CABG) for patients with left main coronary artery disease (LMCAD) have reported conflicting results.

Objectives

We performed a systematic review from inception to 23 May 2021 and one-stage reconstructed individual-patient data meta-analysis (IPDMA) that included 10-year mortality outcomes.

Methods

The primary outcome was 10-year all-cause mortality. Secondary outcomes included myocardial infarction (MI), stroke and unplanned revascularization at 5 years. We did IPDMA using published Kaplan-Meier curves to provide individual data points in coordinates and numbers at risk were used to increase the calibration accuracy of the reconstructed data. Shared frailty model or, when proportionality assumptions were not met, a restricted mean survival time model were fitted to compare outcomes between treatment groups.

Results

Of 583 articles retrieved, 5 RCTs were included. A total of 4595 patients from these 5 RCTs were randomly assigned to PCI (N=2297) or CABG (N=2298). The cumulative 10-year all-cause mortality after PCI and CABG was 12.0% versus 10.6% respectively (HR 1.093, 95% CI: 0.925–1.292; p=0.296). PCI conferred similar time-to-MI (RMST ratio 1.006, 95% CI: 0.992–1.021, p=0.391) and stroke (RMST ratio 1.005, 95% CI: 0.998–1.013, p=0.133) at 5 years. Unplanned revascularization was more frequent following PCI compared with CABG (HR 1.807, 95% CI: 1.524–2.144, p<0.001) at 5 years.

Conclusion

This meta-analysis using reconstructed participant-level time-to-event data showed no statistically significant difference in cumulative 10-year all-cause mortality between PCI versus CABG in the treatment of LMCAD.

Funding Acknowledgement

Type of funding sources: None.

Coronary artery bypass grafting versus percutaneous coronary intervention with stenting for multivessel coronary artery disease without left main coronary disease:reconstructed individual patient data

Background and aims

Data are emerging on 10-year mortality comparing coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI) with stenting for multivessel disease (MVD) without left main (LM) involvement. We conducted an updated two-stage meta-analysis using reconstructed individual patient data to compare long-term mortality between CABG and PCI for patients with MVD without significant LM coronary disease.

Methods

Medline and Embase databases were searched for articles comparing CABG with PCI for MVD. A two-stage meta-analysis was conducted using reconstructed patient level survival data for all-cause mortality with subgroups by SYNTAX score. The shared-frailty and stratified Cox models were fitted to compare survival endpoints.

Results

We screened 1496 studies and included six randomized controlled trials with 7181 patients. PCI was associated with greater 10-year all-cause mortality risk (HR: 1.282, CI: 1.118–1.469, p<0.001) compared with CABG. In patients with low SYNTAX score, 10-year all-cause mortality after PCI was comparable to CABG (HR: 1.102, 0.822–1.479, p=0.516). However, in patients with moderate to high SYNTAX score, 10-year all-cause mortality was significantly higher after PCI compared with CABG (HR: 1.444, 1.122–1.858, p<0.001; HR: 1.856, 1.380–2.497, p<0.001 respectively).

Conclusion

This updated reconstructed individual patient-data meta-analysis revealed a sustained lower cumulative all-cause mortality of CABG over PCI for multivessel disease without LM involvement.

Funding Acknowledgement

Type of funding sources: None.

Systematic review of electrophysiology procedures in patients with obstruction of the inferior vena cava

AIMS

The objective of the study was to conduct a systematic review to describe and compare the different approaches for performing cardiac electrophysiology (EP) procedures in patients with interrupted inferior vena cava (IVC) or equivalent entities causing IVC obstruction.

METHODS

We conducted a structured search to identify manuscripts reporting EP procedures with interrupted IVC or IVC obstruction of any aetiology published up until August 2020. No restrictions were applied in the search strategy. We also included seven local cases that met inclusion criteria.

RESULTS

The analysis included 142 patients (mean age 48.9 years; 48% female) undergoing 143 procedures. Obstruction of the IVC was not known before the index procedure in 54% of patients. Congenital interruption of IVC was the most frequent cause (80%); and, associated congenital heart disease (CHD) was observed in 43% of patients in this setting. The superior approach for ablation was the most frequently used strategy (52%), followed by inferior approach via the azygos or hemiazygos vein (24%), transhepatic approach (14%), and retroaortic approach (10%). Electroanatomical mapping (58%), use of long sheaths (41%), intracardiac echocardiography (19%), transesophageal echocardiography (15%) and remote controlled magnetic navigation (13%) were used as adjuncts to aid performance. Ablation was successful in 135 of 140 procedures in which outcomes were reported. Major complications were only reported in patients undergoing AF ablation, including two patients with pericardial effusion, one of whom required surgical repair, and another patient who died after inadvertent entry into an undiagnosed atrioesophageal fistula from a previous procedure.

CONCLUSION

The superior approach is most frequent approach for performing EP procedures in the setting of obstructed IVC. Transhepatic approach is a feasible alternative, and may provide a "familiar approach" for transseptal access when it is required. Adjunctive use of long sheaths, intravascular echocardiography, electro-anatomical mapping and remote magnetic navigation may be helpful, especially if there is associated complex CHD. With careful planning, EP procedures can usually be successfully performed with a low risk of complications.

Hmox1 (Heme Oxygenase-1) Protects Against Ischemia-Mediated Injury via Stabilization of HIF-1α (Hypoxia-Inducible Factor-1α)

OBJECTIVE

Hmox1 (heme oxygenase-1) is a stress-induced enzyme that catalyzes the degradation of heme to carbon monoxide, iron, and biliverdin. Induction of Hmox1 and its products protect against cardiovascular disease, including ischemic injury. Hmox1 is also a downstream target of the transcription factor HIF-1α (hypoxia-inducible factor-1α), a key regulator of the body's response to hypoxia. However, the mechanisms by which Hmox1 confers protection against ischemia-mediated injury remain to be fully understood. Approach and Results: Hmox1 deficient (Hmox1-/-) mice had impaired blood flow recovery with severe tissue necrosis and autoamputation following unilateral hindlimb ischemia. Autoamputation preceded the return of blood flow, and bone marrow transfer from littermate wild-type mice failed to prevent tissue injury and autoamputation. In wild-type mice, ischemia-induced expression of Hmox1 in skeletal muscle occurred before stabilization of HIF-1α. Moreover, HIF-1α stabilization and glucose utilization were impaired in Hmox1-/- mice compared with wild-type mice. Experiments exposing dermal fibroblasts to hypoxia (1% O2) recapitulated these key findings. Metabolomics analyses indicated a failure of Hmox1-/- mice to adapt cellular energy reprogramming in response to ischemia. Prolyl-4-hydroxylase inhibition stabilized HIF-1α in Hmox1-/- fibroblasts and ischemic skeletal muscle, decreased tissue necrosis and autoamputation, and restored cellular metabolism to that of wild-type mice. Mechanistic studies showed that carbon monoxide stabilized HIF-1α in Hmox1-/- fibroblasts in response to hypoxia.

CONCLUSIONS

Our findings suggest that Hmox1 acts both downstream and upstream of HIF-1α, and that stabilization of HIF-1α contributes to Hmox1's protection against ischemic injury independent of neovascularization.

Co-infection of Cytomegalovirus and Epstein-Barr Virus Diminishes the Frequency of CD56dimNKG2A+KIR- NK Cells and Contributes to Suboptimal Control of EBV in Immunosuppressed Children With Post-transplant Lymphoproliferative Disorder

Post-transplant lymphoproliferative disorder (PTLD) is a rare but potentially life-threatening complication, frequently associated with Epstein-Barr virus (EBV), which develops after solid organ or stem cell transplantation. Immunosuppression received by transplant recipients has a significant impact on the development of PTLD by suppressing the function of T cells. The preferential proliferation of NKG2A-positive natural killer (NK) cells during primary symptomatic EBV infection known as infectious mononucleosis (IM) and their reactivity toward EBV-infected B cells point to a role of NK cell in the immune control of EBV. However, NK cell-mediated immune response to EBV in immunosuppressed transplant recipients who develop PTLD remains unclear. In this study, we longitudinally analyzed the phenotype and function of different NK cell subsets in a cohort of pediatric liver transplant patients who develop PTLD and compared them to those of children with IM. We found persistently elevated plasma EBV DNA levels in the PTLD patients indicating suboptimal anti-viral immune control. PTLD patients had markedly decreased frequency of CD56^dimNKG2A⁺Killer Immunoglobulin-like receptor (KIR)⁻ NK cells from the time of diagnosis through remission compared to those of IM patients. Whilst the proliferation of CD56^dimNKG2A⁺KIR⁻ NK cells was diminished in PTLD patients, this NK cell subset maintained its ability to potently degranulate against EBV-infected B cells. Compared to cytomegalovirus (CMV)-seropositive and -negative IM patients, PTLD patients co-infected with CMV and EBV had significantly higher levels of a CMV-associated CD56^dimNKG2C^hiCD57⁺NKG2A⁻KIR⁺ NK cell subset accumulating at the expense of NKG2A⁺KIR⁻ NK cells. Taken together, our data indicate that co-infection of CMV and EBV diminishes the frequency of CD56^dimNKG2A⁺KIR⁻ NK cells and contributes to suboptimal control of EBV in immunosuppressed children with PTLD.

Impaired cerebral blood flow in type 2 diabetes mellitus - A comparative study with subjective cognitive decline, vascular dementia and Alzheimer's disease subjects

•

CBF impairment is found in T2DM and SCD individuals, which might suggest a preclinical stage of dementia.

•

Comparing to HC, lower CBF in T2DM was due to higher rate of multiple cerebrovascular risk factors.

•

Unlike T2DM, CBF reduction in AD and VD was due to amyloid deposition and microangiopathy respectively.

•

Significant negative correlation between adjusted CBF and HbA1c in all cortical regions in healthy control and T2DM.

The link between non-demented type 2 diabetes mellitus (T2DM) and different types of cognitive impairment is controversial. By controlling for co-morbidities such as cerebral macrovascular and microvascular changes, cerebral atrophy, amyloid burden, hypertension or hyperlipidemia, the current study investigated the cerebral blood flow of T2DM individuals as compared to cognitively impaired subjects recruited from a memory clinic.

15 healthy control (71.8 ± 6.1 years), 18 T2DM (62.5 ± 3.7 years), as well as 8 Subjective Cognitive Decline (69.5 ± 7.5 years), 12 Vascular Dementia (79.3 ± 4.2 years) and 17 Alzheimer’s Disease (75.1 ± 8.2 years) underwent multi-parametric MRI brain scanning. Subjects with T2DM and from the memory clinic also had 18-F Flutametamol PET-CT scanning to look for any amyloid burden. Pseudocontinuous Arterial Spin Labeling (PCASL), MR Angiography Head, 3D FLAIR and 3D T1-weighted sequences were used to quantify cerebral blood flow, cerebrovascular changes, white matter hyperintensities and brain atrophy respectively. Vascular risk factors were retrieved from the medical records. The 37 subjects from memory clinic were classified into subjective cognitive decline (SCD), vascular dementia (VD) and Alzheimer’s disease (AD) subgroups by a multi-disciplinary panel consisting of a neuroradiologist, and 2 geriatricians.

Absolute cortical CBF in our cohort of T2DM, SCD, VD and AD was significantly decreased (p < 0.01) as compared to healthy controls (HC) in both whole brain and eight paired brain regions, after age, normalized grey matter volume and gender adjustment and Bonferroni correction.

Subgroup analysis between T2DM, SCD, VD, and AD revealed that CBF of T2DM was not significantly different from AD, VD or SCD. By controlling for co-morbidities, impaired cortical CBF in T2DM was not related to microangiopathy or amyloid deposition, but to the interaction of triple risk factors (such as diabetes mellitus, hypertension, and hyperlipidemia).

There was statistically significant negative correlation (p ≤ 0.05) between adjusted CBF and HbA1c in all brain regions of T2DM and HC (with partial correlation ranging from −0.30 to −0.46).

Taken together, altered cerebral blood flow in T2DM might be related to disruption of cerebrovascular autoregulation related to vascular risk factors, and such oligemia occurred before clinical manifestation due to altered glycemic control.

Androgens Stimulate EPC-Mediated Neovascularization and Are Associated with Increased Coronary Collateralization

Endothelial progenitor cells (EPCs) play a key role in neovascularization and have been linked to improved cardiovascular outcomes. Although there is a well-established inverse relationship between androgen levels and cardiovascular mortality in men, the role of androgens in EPC function is not fully understood. In this study, we investigated the effects of androgens on 2 subpopulations of EPCs, early EPCs (EEPCs) and late outgrowth EPCs (OECs), and their relationships with coronary collateralization. Early EPCs and OECs were isolated from the peripheral blood of young healthy men and treated with dihydrotestosterone (DHT) with or without androgen receptor (AR) antagonist, hydroxyflutamide, in vitro. Dihydrotestosterone treatment enhanced AR-mediated proliferation, migration, and tubulogenesis of EEPCs and OECs in a dose-dependent manner. Furthermore, DHT augmented EPC sensitivity to extracellular stimulation by vascular endothelial growth factor (VEGF) via increased surface VEGF receptor expression and AKT activation. In vivo, xenotransplantation of DHT pretreated human EPCs augmented blood flow recovery and angiogenesis in BALB/c nude male mice, compared to mice receiving untreated EPCs, following hindlimb ischemia. In particular, DHT pretreated human OECs exhibited higher reparative potential than EEPCs in augmenting postischemic blood flow recovery in mice. Furthermore, whole blood was collected from the coronary sinus of men with single vessel coronary artery disease (CAD) who underwent elective percutaneous intervention (n = 23). Coronary collateralization was assessed using the collateral flow index. Serum testosterone and EPC levels were measured. In men with CAD, circulating testosterone was positively associated with the extent of coronary collateralization and the levels of OECs. In conclusion, androgens enhance EPC function and promote neovascularization after ischemia in mice and are associated with coronary collateralization in men.

Parental perspectives on decision-making about hypospadias surgery

INTRODUCTION

Many parents who choose hypospadias repair for their son experience decisional conflict and regret. The utilization of a shared decision-making process may address the issue of decisional conflict and regret in hypospadias repair by engaging both parents and physicians in decision-making.

OBJECTIVE

The objective of this study was to develop a theoretical framework of the parental decision-making process about hypospadias surgery to inform the development of a decision aid.

STUDY DESIGN

We conducted semistructured interviews were conducted with parents of children with hypospadias to explore their role as proxy decision-makers, inquiring about their emotions/concerns, informational needs, and external/internal influences. Interviews were conducted until no new themes were identified, analyzing them iteratively using open, axial, and selective coding. The iterative approach entails a cyclical process of conducting interviews and analyzing transcripts while the data collection process is ongoing. This allows the researcher to make adjustments to the interview guide as necessary based on preliminary data analysis in order to explore themes that emerge from early interviews with parents. Grounded theory methods were used to develop an explanation of the surgical decision-making process.

RESULTS

Sixteen mothers and one father of seven preoperative and nine postoperative patients (n = 16) with distal (8) and proximal (8) meatal locations were interviewed. Four stages of the surgical decision-making process were identified: (1) processing the diagnosis, (2) synthesizing information, (3) processing emotions and concerns, and (4) finalizing the decision (Extended Summary Figure). Core concepts in each stage of the decision-making process were identified. Primary concerns included anxiety/fear about the child not waking up from anesthesia and their inability to be present in the operating room. Parents incorporated information from the Internet, medical providers, and their social network as they sought to relieve confusion and anxiety while building trust/confidence in their child's surgeon.

DISCUSSION

The findings of this study contribute to our understanding of decision-making about hypospadias surgery as a complex and multifaceted process. The overall small sample size is typical and expected for qualitative research studies. The primary limitation of the study, however, is the underrepresentation of fathers, minorities, and same-sex couples.

CONCLUSIONS

This study provides an initial framework of the parental decision-making process for hypospadias surgery that will inform the development of a decision aid. Future stages of decision aid development will focus on recruitment of fathers, minorities, and same-sex couples in order to enrich the perspectives of our work.

Community engagement of adolescents in the development of a patient-centered outcome tool for adolescents with a history of hypospadias repair

INTRODUCTION

Hypospadias may lead to long-term issues with urination, sexual function and psychosocial well-being. Limited evidence exists regarding the healthcare communication preferences of male adolescents regarding sensitive topics.

OBJECTIVE

The purpose of this qualitative study was to explore the healthcare communication preferences of male adolescents regarding sensitive topics (e.g. urinary and sexual issues) and engage them in the initial stages of development of a patient-centered outcome tool for adolescents with a history of hypospadias repair.

STUDY DESIGN

A multidisciplinary team with communication design expertise, pediatric urology experts, and health services researchers developed a self-reported toolkit for adolescent patients who had hypospadias repair as children. The toolkit featured short writing/diagramming exercises and scales to facilitate participant reflections about genital appearance, urination, sexual function, and psychosocial well-being. We recruited students from two local high schools for two focus groups to obtain feedback about the usability/acceptability of the toolkit's appearance/content. We inquired about language preferences and preferred format and/or setting for sharing sensitive information with researchers. The focus groups were audio recorded, professionally transcribed, checked for accuracy, and analyzed by two coders using qualitative content analysis. Major themes and subthemes were identified, and representative quotes were selected.

RESULTS

We conducted two focus groups in January 2018 with 33 participants, aged 14-18 years. Participants preferred language that would make patients feel comfortable and serious, clinical language rather than slang terms/sexual humor (Extended Summary Table). They recommended avoidance of statements implying that something is wrong with a patient or statements that would pressure the patient into providing answers. They suggested fill-in-the-blank and open-ended responses to encourage freedom of expression and colorful graphics to de-emphasize the test-like appearance of the toolkit. Most participants preferred a toolkit format to a one-on-one interview to discuss sensitive topics such as urinary or sexual issues. Participants would prefer either a male interviewer or would like to have a choice of interviewer gender for individual qualitative interviews, and they recommended a focus group leader with a history of hypospadias repair.

DISCUSSION

This study provides a rich description of a group of male high school students' experiences with healthcare providers and researchers. Its qualitative design limits generalizability, and our findings may not be similar to those of adolescents with a history of hypospadias repair.

CONCLUSION

We used focus group feedback on the toolkit prototype to refine the tool for use in a future study of adolescents with a history of hypospadias repair.

A randomised trial comparing real-time double-lumen endobronchial tube placement with the Disposcope® with conventional blind placement

Double-lumen endobronchial tube placement is challenging. This study compared double-lumen tube placement with the Disposcope^® , a wireless videostylet allowing real-time visualisation, with conventional blind placement. Patients undergoing elective thoracic surgery with normal airways requiring one-lung ventilation were randomly allocated into two groups (27 patients in each group). The Disposcope was used to assist left-sided double-lumen tube placement in one group, and conventional blind placement was performed in the control group. Placement in both groups was checked with fibreoptic bronchoscopy. The Disposcope-assisted group had a shorter total mean (SD) placement time (18.6 (2.5) s vs. 21.4 (2.9) s, p < 0.001), laryngoscopy to end of auscultation time (83.4 (3.0) s vs. 93.9 (5.7) s, p < 0.001) and total operation time (130.7 (6.1) s vs. 154.5 (6.3) s, p < 0.001). In the Disposcope-assisted group, the double-lumen tube was inserted in the correct side in all patients (100.0%), whereas in the conventional group, the double-lumen tube was placed in the correct side in 25 (92.6%) patients and in the wrong side in 2 (7.4%) patients; the difference was not significant (p = 0.150). In the Disposcope-assisted group, the double-lumen tube was inserted to the optimal depth in 24 (88.9%) patients, whereas in the conventional group it was inserted to the optimal depth in one (4.0%) patient. The Disposcope increased the success rate of double-lumen tube placement, and shortened the total operation time when compared with standard placement with confirmation using fibreoptic bronchoscopy, and may replace the conventional method.

The ability of a limited metabolic assessment to identify pediatric stone formers with metabolic abnormalities

INTRODUCTION

American Urological Association guidelines recommend a urinary metabolic evaluation after the first stone event in all pediatric stone patients. Prior studies identified hypercalciuria and urine hypovolemia as the most common abnormalities in children with urolithiasis. Recent data suggest that hypocitraturia is most prevalent. It was hypothesized that a limited evaluation would detect the majority of clinically significant metabolic abnormalities in pediatric stone formers.

MATERIAL AND METHODS

A retrospective analysis of all children (<18 years of age) with renal/ureteral calculi evaluated at the study institution from 2005 to 2015 was performed. Children with ≥ one 24-h urinary metabolic profile after a clinical visit for renal/ureteral calculi were included. Those with bladder stones and those with undercollection or overcollection or missing urinary creatinine were excluded. Demographics and data from the first urinary metabolic profile and stone analyses were collected. The sensitivity, specificity, and positive and negative predictive value (NPV) of a limited urinary metabolic evaluation consisting of four parameters (24-h calcium, citrate, and oxalate and low urinary volume) were compared to a complete urinary metabolic profile. The number and type of metabolic abnormalities that would have been missed with this limited evaluation weredetermined.

RESULTS

Of 410 patients, 21 were excluded for age ≥18 years, 13 for bladder stones, 248 for overcollections, 38 for undercollections, and 10 for missing creatinine. This left 80 patients for inclusion: median age 11.4 years, 60% female, and 96.3% white. Of the entire cohort, 69.6% had hypocitraturia, 52.5% had low urine volume, and 22.5% had hypercalciuria. Sensitivity was 87.5%. Specificity could not be calculated because no patients had a normal complete metabolic evaluation. The NPV was zero, and the positive predictive value was 100%, but these are artifacts resulting from the absence of patients with a normal complete metabolic evaluation. Of the 80 patients, 10 had at least one abnormality missed by a limited metabolic evaluation (Table 1). The missed abnormalities were high pH (n = 6), abnormal 24-h phosphorus (low in 1 patient and high in 1 patient), low 24-h magnesium (n = 3), low 24-h potassium (n = 3), and high 24-h sodium (n = 4).

DISCUSSION

A limited urinary metabolic evaluation would have detected the vast majority of clinically significant metabolic abnormalities in the study sample. Approximately two-thirds of the study patients submitted inadequate 24-h urine specimens.

CONCLUSIONS

A simplified approach to metabolic evaluation in first-time stone formers with a stone analysis available was proposed. This streamlined approach could simplify the metabolic evaluation and reduce health care costs.

Emergence of CD4+ and CD8+ Polyfunctional T Cell Responses Against Immunodominant Lytic and Latent EBV Antigens in Children With Primary EBV Infection

Long term carriers were shown to generate robust polyfunctional T cell (PFC) responses against lytic and latent antigens of Epstein-Barr virus (EBV). However, the time of emergence of PFC responses against EBV antigens, pattern of immunodominance and difference between CD4+ and CD8+ T cell responses during various stages of EBV infection are not clearly understood. A longitudinal study was performed to assess the development of antigen-specific PFC responses in children diagnosed to have primary symptomatic (infectious mononucleosis [IM]) and asymptomatic (AS) EBV infection. Evaluation of IFN-γ secreting CD8+ T cell responses upon stimulation by HLA class I-specific peptides of EBV lytic and latent proteins by ELISPOT assay followed by assessment of CD4+ and CD8+ PFC responses upon stimulation by a panel of overlapping EBV peptides for co-expression of IFN-γ, TNF-α, IL-2, perforin and CD107a by flow cytometry were performed. Cytotoxicity of T cells against autologous lymphoblastoid cell lines (LCLs) as well as EBV loads in PBMC and plasma were also determined. Both IM and AS patients had elevated PBMC and plasma viral loads which declined steadily during a 12-month period from the time of diagnosis whilst decrease in the magnitude of CD8+ T cell responses toward EBV lytic peptides in contrast to increase toward latent peptides was shown with no significant difference between those of IM and AS patients. Both lytic and latent antigen-specific CD4+ and CD8+ T cells demonstrated polyfunctionality (defined as greater or equal to three functions) concurrent with enhanced cytotoxicity against autologous LCLs and steady decrease in plasma and PBMC viral loads over time. Immunodominant peptides derived from BZLF1, BRLF1, BMLF1 and EBNA3A-C proteins induced the highest proportion of CD8+ as well as CD4+ PFC responses. Diverse functional subtypes of both CD4+ and CD8+ PFCs were shown to emerge at 6–12 months. In conclusion, EBV antigen-specific CD4+ and CD8+ PFC responses emerge during the first year of primary EBV infection, with greatest responses toward immunodominant epitopes in both lytic and latent proteins, correlating to steady decline in PBMC and plasma viral loads.

Direct health-care cost utilization in Hong Kong inflammatory bowel disease patients in the initial 2 years following diagnosis

BACKGROUND AND AIM

There are scanty data on the health-care utilization from Asia where the incidence of inflammatory bowel disease (IBD) is rising rapidly. We aim to determine the direct health-care costs in the first 2 years of diagnosis in an IBD cohort from Hong Kong and the factors associated with high cost outliers.

METHODS

This is a retrospective cohort study that included patients newly diagnosed with IBD in a territory-wide IBD registry. Patients' clinical information, hospitalization records, investigations, and IBD treatments were retrieved for up to 2 years following diagnosis of IBD.

RESULTS

Four hundred and thirty-five newly diagnosed IBD patients were included: 198 with Crohn's disease and 237 with ulcerative colitis. Total direct medical expenditure for this cohort 2 years after the IBD diagnosis was $7 072 710: hospitalizations (33%), 5-aminosalicylic acid (23%), imaging and endoscopy (17%), outpatient visits (10%), surgery (8%), and biologics (6%). Mean direct medical costs per patient-year were significantly higher for Crohn's disease ($9918) than ulcerative colitis ($6634; P, 0.001). The total direct health-care cost decreased significantly after transition to the second year (P < 0.01). High cost (> 90th percentile) outliers were associated with surgery (OR 7.1, 95% CI 2.9-17.2) and low hemoglobin on presentation (OR 0.83, 95% CI 0.70-0.96).

CONCLUSIONS

Hospitalization and 5-aminosalicylic acid usage accounted for 56% of total direct medical costs in the first 2 years of our newly diagnosed IBD patients. Direct health-care costs were higher in the first year compared with the second year of diagnosis. Surgery and low hemoglobin on presentation were associated with high cost outliers.

A One-Year Hospital-Based Analysis of Sports Injuries

Objectives

(1) To survey and analyse the pattern of sports injuries; (2) to make implication from the results.

Methodology

Subjects with sports injuries attending the emergency department of Princess Margaret Hospital in 2006 were retrieved via the Injury Surveillance System. The characteristics of the subjects and their injuries were evaluated.

Results

In 2006, 709 subjects had sports injuries, from which 83% were male. The median age was 19. Age below 20 accounted for 53% of the attendance. Football (35%), basketball (25%) and cycling (9%) were the three commonest sport-injury activities. All sports injuries had the maximum AIS ≤3 and 83% had MAIS of 1 only. Overall, 39% had contusion and scrape, 36% with sprain and strain, and 18% had fracture. Nearly half (47%) had lower limb injury; 30% and 24% had upper limb injury and head injury respectively. Contusion and scrape of the head, and sprain and strain of the lower limb were the two commonest injuries in football and basketball. In cycling, two-thirds suffered from contusion and scrape of any body region and 57% of those involved the head.

Conclusion

Sports injury surveillance with characterised patterns of injuries helped to devise prevention measures.

Evaluation of the molecular Xpert Xpress Flu/RSV assay vs. Alere i Influenza A & B assay for rapid detection of influenza viruses

A new FDA-approved Xpert Xpress Flu/RSV assay has been released for rapid influenza virus detection. We collected 134 nasopharyngeal specimens to compare the diagnostic performance of the Xpert assay and the Alere i Influenza A & B assay for influenza A and B virus detection. The Xpert assay demonstrated 100% and 96.3% sensitivity to influenza A and influenza B virus respectively. Its specificity was 100% for both viruses. The Alere i assay demonstrated slightly lower sensitivity but similar specificity to the Xpert Xpress assay. Although the Xpert assay (30 min) required longer processing time than the Alere assay (15 min), the handling procedure of the Alere assay was more complicated than the Xpert assay. As the GenXpert system has higher throughput than the Alere system, it is more suitable for hospital clinical laboratories. Overall, the new Xpert Xpress Flu/RSV assay is a reliable and useful tool for rapid influenza detection.

Atrial Fibrillation in Hypertrophic Cardiomyopathy

Hypertrophic cardiomyopathy (HCM) is an inherited cardiac disorder with a spectrum of clinical manifestations. Patients with HCM are predisposed to developing atrial fibrillation (AF) due primarily to advanced diastolic dysfunction and left atrial (LA) dilatation and remodelling. Atrial fibrillation causes a progressive symptomatic and functional decline, as well as increased thromboembolic risk and mortality, particularly in the setting of rapid ventricular rates and left ventricular outflow tract (LVOT) obstruction. The mainstay of management of AF in HCM is a combination of non-pharmacological lifestyle and risk factor modification, long-term anticoagulation, and rhythm control with antiarrhythmic medications. There is a growing body of evidence indicating that an early and aggressive rhythm control strategy may result in more favourable outcomes.

A case of base rate bias, or are adolescents at a higher risk of developing complications after catheterizable urinary channel surgery?

OBJECTIVE

Adolescents are considered to be at high risk of developing complications after lower genitourinary tract reconstruction. This perception may be due to base rate bias, where clinicians favor specific information (adolescents with complications), while ignoring more general information (number of total adolescents being followed). The goal of this study was to assess whether age was a true risk factor for subfascial and stomal revisions after continent catheterizable urinary (CCU) channel procedures.

MATERIALS AND METHODS

Consecutive patients aged <21 years and who underwent appendicovesicostomy and Monti surgery at the present institution were retrospectively reviewed; demographic and surgical data were collected. Time to subfascial or stomal revision was stratified by age at initial surgery (child: <8, preteen: 8-12, adolescent: 13-17, adult: ≥18 years old) and analyzed with Cox proportional-hazards regression. Secondary analyses included: different age categories at initial surgery (<8, 8-11, 12-15, 16-19, ≥20 years), analyzing age as a continuous and a time-varying covariate.

RESULTS

Of the 510 patients with CCU channels (median age at surgery: 7.9 years), 63 (12.4%) had subfascial and 53 (10.4%) had stomal revision (median follow-up: 6.8 years). Median age at subfascial and stomal revision was 11.3 and 10.3 years, respectively. Preteens contributed 33.0% and adolescents contributed 29.3% of the total follow-up time (3263.9 person-years). Over 80% of revisions occurred within 5 years of surgery, regardless of age at initial surgery (P ≥ 0.57) (Summary table). On multivariate analysis, age at initial surgery was not associated with undergoing subfascial (P ≥ 0.62) or stomal revisions (P ≥ 0.69). Montis were 2.1 times more likely than appendicovesicostomies to undergo a subfascial revision (P = 0.03). No other variables were associated with the risk of subfascial or stomal revision (P ≥ 0.11). Secondary analyses provided similar results.

DISCUSSION

Since the median age at surgery was 8 years old and most complications occurred within the first 5 years of follow-up, it is not surprising that most revisions occurred in 8-13 year olds. Pediatric urologists appear to base their impression of adolescents being "high risk" on specific information (adolescents having complications), while subconsciously ignoring more general information (adolescents represent a large proportion of patients in follow-up). This study had several limitations: channel complications treated non-surgically (e.g. prolonged catheterization) were not included. The findings may not be generalizable to other genitourinary reconstructive procedures or clinical settings.

CONCLUSIONS

While complications were twice as high in Monti channels than appendicovesicostomies, no single age group was at increased risk. The impression that adolescents are a high-risk group appears to represent a base rate bias.

Validation of antibiotic charges in administrative data for outpatient pediatric urologic procedures

INTRODUCTION

The use of administrative health data for research has prompted questions about its validity for this purpose.

OBJECTIVE/STUDY DESIGN

The purpose of this study was to determine the concordance of Pediatric Health Information System (PHIS) perioperative antibiotic charges with the institution's medication administration data for males <10 years old and who underwent outpatient penile/inguinal procedures from July 2013 to March 2015.

RESULTS

There was 93.9% positive and negative agreement between perioperative antibiotic charges versus administration. The sensitivity and specificity were 96.8% and 87.2%, respectively. The positive and negative predictive values were 94.6% and 92.2%, respectively.

CONCLUSION

This study indicated strong agreement between PHIS pharmacy charges and medication administration.

Long-term follow-up of composite bladder augmentation incorporating stomach in a multi-institutional cohort of patients with cloacal exstrophy

INTRODUCTION

Composite bladder augmentation, incorporating gastric and bowel segments, has the theoretical advantage of metabolic neutrality while potentially avoiding the morbidities of gastrocystoplasty, such as hematuria-dysuria syndrome. The most common indication for this operation is a paucity of bowel, such as in cloacal exstrophy. Despite several early descriptive studies of this technique, there are no reports, to date, of long-term follow-up in this population.

OBJECTIVE

To describe the outcomes of composite bladder augmentation utilizing stomach in a cohort of cloacal exstrophy patients.

MATERIALS AND METHODS

A retrospective review of cloacal exstrophy patients who underwent composite bladder augmentation from 1984 to 2006 at two institutions was performed. The incidence of mortality and morbidities related to augmentation was evaluated.

RESULTS

Eleven patients with cloacal exstrophy underwent composite bladder augmentation. Median age at initial augmentation was 6.4 years (interquartile range (IQR) 4.4-9.1). Median follow-up was 13.2 years (IQR 11.2-24.6). The Summary table describes the types of composite bladder augmentations. Of the three patients with pre-operative metabolic acidosis, two improved with composite bladder augmentation and one developed metabolic alkalosis. Three developed hematuria-dysuria syndrome: one improved with staged ileocystoplasty, and two had persistent symptoms successfully treated with H2 receptor blockers. Two of 11 developed symptomatic bladder stones. There were no reported bladder perforations, bladder malignancies, conversions to incontinent urinary diversions, or deaths.

CONCLUSION

With long-term follow-up, very few patients developed metabolic acidosis/alkalosis after composite bladder augmentation. The composite bladder augmentation will continue to be used in patients with cloacal exstrophy, in order to minimize the impact on the pre-existing short gut in these patients.

Ambulatory patients with spina bifida are 50% more likely to be fecally continent than non-ambulatory patients, particularly after a MACE procedure

INTRODUCTION

While fecal incontinence (FI) affects many patients with spina bifida (SB), it is unclear if it is associated with ambulatory status.

OBJECTIVE

To determine if ambulatory status is associated with FI, and a potential confounding variable, in patients with and without a Malone antegrade continence enema (MACE).

STUDY DESIGN

This study retrospectively reviewed of patients aged ≥8 years with SB who were enrolled in an international quality of life study at outpatient visits (January 2013 to September 2015). Patients reported FI over the last 4 weeks (strict criteria: any FI/accidents vs no FI). Patients unable to self-report FI due to developmental delay were excluded. Those who were ambulating outdoors with/without braces/crutches were considered community ambulators. Non-parametric tests and logistic regression were used for analysis.

RESULTS

A total of 115 patients with a MACE and 57 without a MACE were similar in gender (P = 0.99), ventriculoperitoneal status (P = 0.15) and age (16.0 vs 15.4 years, P = 0.11). Median ages at MACE procedure and follow-up were 7.0 and 8.2 years, respectively, and all used the MACE ≥3x/week. They were less likely to be ambulators (54.8 vs 71.9%, P = 0.03). In patients with a MACE, 64 (55.7%) had total fecal continence, compared with 29 (50.9%) without a MACE (P = 0.62). In the MACE group, ambulators were more likely to be continent compared with non-ambulatory patients (65.1 vs 44.2%, P = 0.04) (Table). Although not statistically significant, a similar difference was observed in the non-MACE group (56.1 vs 37.5%, P = 0.25). In the MACE group, continent and incontinent patients, regardless of ambulatory status, had similar rates of MACE use, additive use and time for MACE completion (P ≥ 0.43). MACE ambulators were more likely to be continent than MACE non-ambulators on multivariate analysis (OR 3.26, P = 0.01).

DISCUSSION

This study reported higher than typical FI rates since: (1) it used a stringent definition of total fecal continence; (2) patients without FI were perhaps less likely to participate; and (3) it relied on patient-reported rather than clinician-reported outcomes. This cross-sectional study should not be interpreted as "MACE procedure is ineffective;" this would require a longitudinal study. The present findings may not apply to young children or those with significant developmental delay (patients excluded from the study).

CONCLUSIONS

Ambulatory patients with SB are 50% more likely to have total fecal continence on long-term follow-up, particularly after a MACE procedure. Ambulatory status is a significant confounder of FI and should be considered in future analyses.

Routine Implant of Biventricular Devices Guided by an Electroanatomic Mapping System - Ready for Prime-Time?

Biventricular devices play an important adjunctive role in the treatment of heart failure. However, biventricular device implantation is associated with significant radiation exposure and a high proportion of non-response to cardiac resynchronization therapy (CRT). The use of electroanatomic mapping (EAM) during biventricular device implantation may help overcome these issues. This article will review the literature on the role of EAM in biventricular device implantation.

Characterization of Endothelial Progenitor Cell Interactions with Human Tropoelastin

The deployment of endovascular implants such as stents in the treatment of cardiovascular disease damages the vascular endothelium, increasing the risk of thrombosis and promoting neointimal hyperplasia. The rapid restoration of a functional endothelium is known to reduce these complications. Circulating endothelial progenitor cells (EPCs) are increasingly recognized as important contributors to device re-endothelialization. Extracellular matrix proteins prominent in the vessel wall may enhance EPC-directed re-endothelialization. We examined attachment, spreading and proliferation on recombinant human tropoelastin (rhTE) and investigated the mechanism and site of interaction. EPCs attached and spread on rhTE in a dose dependent manner, reaching a maximal level of 56±3% and 54±3%, respectively. EPC proliferation on rhTE was comparable to vitronectin, fibronectin and collagen. EDTA, but not heparan sulfate or lactose, reduced EPC attachment by 81±3%, while full attachment was recovered after add-back of manganese, inferring a classical integrin-mediated interaction. Integrin αVβ3 blocking antibodies decreased EPC adhesion and spreading on rhTE by 39±3% and 56±10% respectively, demonstrating a large contribution from this specific integrin. Attachment of EPCs on N-terminal rhTE constructs N25 and N18 accounted for most of this interaction, accompanied by comparable spreading. In contrast, attachment and spreading on N10 was negligible. αVβ3 blocking antibodies reduced EPC spreading on both N25 and N18 by 45±4% and 42±14%, respectively. In conclusion, rhTE supports EPC binding via an integrin mechanism involving αVβ3. N25 and N18, but not N10 constructs of rhTE contribute to EPC binding. The regulation of EPC activity by rhTE may have implications for modulation of the vascular biocompatibility of endovascular implants.

Comparison of platinum chromium everolimus-eluting stent with cobalt chromium everolimus-eluting stent in unselected patients undergoing percutaneous coronary intervention

OBJECTIVE

The recent PLATINUM trial has demonstrated that the use of the new generation platinum chromium everolimus-eluting stents (PtCr-EES) yield clinical outcomes similar to those obtained by the use of cobalt chromium everolimus-eluting stents (CoCr-EES) in selected patients with 1 or 2 de novo coronary artery lesions. This study aimed to compare the safety and efficacy of the PtCr-EES and CoCr-EES in unselected patients from a real-life single-center registry.

PATIENTS AND METHODS

  From July 2009 through November 2010, 788 consecutive patients in our institution with symptomatic coronary artery disease who were treated with the CoCr-EES (n = 410) or PtCr-EES (n = 378) were enrolled into this study. The primary endpoint of the study was target-lesion failure (TLF) at 12-month follow-up and the secondary endpoints were major adverse cardiovascular events and stent thrombosis.

RESULTS

The prevalence of TLF in the PtCr-EES group (4.5%) was similar to that in the CoCr-EES group (3.9%). In addition, there were no significant differences in the 12-month rates of cardiac death (2.1% vs. 1.5%), myocardial infarction (2.4% vs. 3.9%), ischemia-driven target lesion revascularization (2.4% vs. 2.2%), and definite or probable stent thrombosis (0.5% vs. 1.5%, all p > 0.05).

CONCLUSIONS

At 12-month follow-up, the PtCr-EES is comparable in safety and efficacy to the CoCr-EES in unselected patients with coronary artery diseases.

Neuromyelitis optica and multiple sclerosis: Seeing differences through optical coherence tomography

Neuromyelitis optica (NMO) is an inflammatory autoimmune disease of the central nervous system that preferentially targets the optic nerves and spinal cord. The clinical presentation may suggest multiple sclerosis (MS), but a highly specific serum autoantibody against the astrocytic water channel aquaporin-4 present in up to 80% of NMO patients enables distinction from MS. Optic neuritis may occur in either condition resulting in neuro-anatomical retinal changes. Optical coherence tomography (OCT) has become a useful tool for analyzing retinal damage both in MS and NMO. Numerous studies showed that optic neuritis in NMO typically results in more severe retinal nerve fiber layer (RNFL) and ganglion cell layer thinning and more frequent development of microcystic macular edema than in MS. Furthermore, while patients’ RNFL thinning also occurs in the absence of optic neuritis in MS, subclinical damage seems to be rare in NMO. Thus, OCT might be useful in differentiating NMO from MS and serve as an outcome parameter in clinical studies.

The relationship between endothelial progenitor cell populations and epicardial and microvascular coronary disease-a cellular, angiographic and physiologic study

BACKGROUND

Endothelial progenitor cells (EPCs) are implicated in protection against vascular disease. However, studies using angiography alone have reported conflicting results when relating EPCs to epicardial coronary artery disease (CAD) severity. Moreover, the relationship between different EPC types and the coronary microcirculation is unknown. We therefore investigated the relationship between EPC populations and coronary epicardial and microvascular disease.

METHODS

Thirty-three patients with a spectrum of isolated left anterior descending artery disease were studied. The coronary epicardial and microcirculation were physiologically interrogated by measurement of fractional flow reserve (FFR), index of microvascular resistance (IMR) and coronary flow reserve (CFR). Two distinct EPC populations (early EPC and late outgrowth endothelial cells [OECs]) were isolated from these patients and studied ex vivo.

RESULTS

There was a significant inverse relationship between circulating OEC levels and epicardial CAD severity, as assessed by FFR and angiography (r=0.371, p=0.04; r=-0.358, p=0.04; respectively). More severe epicardial CAD was associated with impaired OEC migration and tubulogenesis (r=0.59, p=0.005; r=0.589, p=0.004; respectively). Patients with significant epicardial CAD (FFR<0.75) had lower OEC levels and function compared to those without hemodynamically significant stenoses (p<0.05). In contrast, no such relationship was seen for early EPC number and function, nor was there a relationship between IMR and EPCs. There was a significant relationship between CFR and OEC function.

CONCLUSIONS

EPC populations differ in regards to their associations with CAD severity. The number and function of OECs, but not early EPCs, correlated significantly with epicardial CAD severity. There was no relationship between EPCs and severity of coronary microvascular disease.

Hand, foot and mouth disease in an immunocompetent adult due to Coxsackievirus A6

Hand, foot and mouth disease most commonly occurs in children less than 10 years old, but can occur in immunocompetent adults. We describe a 37-year-old immunocompetent man who presented with multiple painful papules and vesicles on his palms and feet together with vesicles inside the mouth. Real-time polymerase chain reaction revealed Coxsackievirus A6 in the vesicle fluid from the feet, throat swab, and rectal swab. Since the disease is highly contagious, to contain the infection it is prudent to recognise that hand, foot and mouth disease can occur in immunocompetent adults.