Long-term results of ablation index guided atrial fibrillation ablation: insights after 5+ years of follow-up from the MPH AF Ablation Registry

Background

Catheter ablation (CA) for symptomatic atrial fibrillation (AF) offers the best outcomes for patients. Despite the benefits of CA, a significant proportion of patients suffer a recurrence; hence, there is scope to potentially improve outcomes through technical innovations such as ablation index (AI) guidance during AF ablation. We present real-world 5-year follow-up data of AI-guided pulmonary vein isolation.

Methods

We retrospectively followed 123 consecutive patients who underwent AI-guided CA shortly after its introduction to routine practice. Data were collected from the MPH AF Ablation Registry with the approval of the institutional research board.

Results

Our patient cohort was older, with higher BMI, greater CHA2DS2-VASc scores, and larger left atrial sizes compared to similar previously published cohorts, while gender balance and other characteristics were similar. The probability of freedom from atrial arrhythmia with repeat procedures is as follows: year 1: 0.95, year 2: 0.92, year 3: 0.85, year 4: 0.79, and year 5: 0.72. Age >75 years (p = 0.02, HR: 2.7, CI: 1.14-6.7), BMI >35 kg/m2 (p = 0.0009, HR: 4.6, CI: 1.8-11.4), and left atrial width as measured on CT in the upper quartile (p = 0.04, HR: 2.5, CI: 1-5.7) were statistically significant independent predictors of recurrent AF.

Conclusion

AI-guided CA is an effective treatment for AF, with 95.8% of patients remaining free from atrial arrhythmia at 1 year and 72.3% at 5 years, allowing for repeat procedures. It is safe with a low major complication rate of 1.25%. Age >75 years, BMI >35 kg/m2, and markedly enlarged atria were associated with higher recurrence rates.

Prognostic value of chronic kidney disease in patients undergoing left atrial appendage occlusion

AIMS

Atrial fibrillation (AF) and chronic kidney disease (CKD) often coexist and share an increased risk of thrombo-embolism (TE). CKD concomitantly predisposes towards a pro-haemorrhagic state. Our aim was to evaluate the prognostic value of CKD in patients undergoing percutaneous left atrial appendage occlusion (LAAO).

METHODS AND RESULTS

A total of 2124 consecutive AF patients undergoing LAAO were categorized into CKD stage 1+2 (n = 1089), CKD stage 3 (n = 796), CKD stage 4 (n = 170), and CKD stage 5 (n = 69) based on the estimated glomerular filtration rate at baseline. The primary endpoint included cardiovascular (CV) mortality, TE, and major bleeding. The expected annual TE and major bleeding risks were estimated based on the CHA2DS2-VASc and HAS-BLED scores. A non-significant higher incidence of major peri-procedural adverse events (1.7 vs. 2.3 vs. 4.1 vs. 4.3) was observed with worsening CKD (P = 0.14). The mean follow-up period was 13 ± 7 months (2226 patient-years). In comparison to CKD stage 1+2 as a reference, the incidence of the primary endpoint was significantly higher in CKD stage 3 (log-rank P-value = 0.04), CKD stage 4 (log-rank P-value = 0.01), and CKD stage 5 (log-rank P-value = 0.001). Left atrial appendage occlusion led to a TE risk reduction (RR) of 72, 66, 62, and 41% in each group. The relative RR of major bleeding was 58, 44, 51, and 52%, respectively.

CONCLUSION

Patients with moderate-to-severe CKD had a higher incidence of the primary composite endpoint. The relative RR in the incidence of TE and major bleeding was consistent across CKD groups.

Levodopa/Carbidopa to Augment the Treatment of Amblyopia: A Report by the American Academy of Ophthalmology

PURPOSE

To review the published literature on the use of levodopa/carbidopa to augment the treatment of amblyopia.

METHODS

Literature searches for English language studies were last conducted in October 2022 in the PubMed database with no date restrictions. The combined searches yielded 55 articles, of which 23 were reviewed in full text. Twelve of these were considered appropriate for inclusion in this assessment and were assigned a level of evidence rating by the panel methodologist. Nine studies were rated level I, and 3 studies were rated level II; there were no level III studies.

RESULTS

The duration of treatment was limited to 3 to 16 weeks because of concern about long-term adverse effects such as tardive dyskinesia. This complication was not reported in any of the study participants. The dose of levodopa ranged from 1.5 to 8.3 mg/kg/day, generally divided into 3 daily doses. The carbidopa dose was approximately 25% of the levodopa dose in all treatments. Evidence from these studies indicates that augmenting traditional patch occlusion therapy with the oral administration of levodopa/carbidopa can improve the vision of amblyopic children, but the effect was small (0.17-0.3 logarithm of the minimum angle of resolution [logMAR] units) and only statistically significant when compared with patching alone in 2 of the 12 studies cited. Regression of vision was reported in the majority of studies (9 of 12 reported; range, 0-0.17 logMAR unit regression) after discontinuation of therapy. Short-term side effects of the medications were not consistently reported but were most frequently mild and included headache and nausea.

CONCLUSIONS

The best available evidence is currently insufficient to show that augmenting amblyopia therapy using up to 16 weeks of levodopa/carbidopa will result in meaningful improvement in visual acuity. Given the potential for significant side effects such as tardive dyskinesia with long-term therapy, levodopa/carbidopa does not appear to be a viable option for amblyopia therapy FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Outcomes of Patients With Takotsubo Syndrome Compared With Type 1 and Type 2 Myocardial Infarction

Background Takotsubo syndrome (TS) and myocardial infarction (MI) share similar clinical and laboratory characteristics but have important differences in causes, demographics, management, and outcomes. Methods and Results In this observational study, the National Inpatient Sample and National Readmission Database were used to identify patients admitted with TS, type 1 MI, or type 2 MI in the United States between October 1, 2017, and December 31, 2019. We compared patients hospitalized with TS, type 1 MI, and type 2 MI with respect to key features and outcomes. Over the 27-month study period, 2 035 055 patients with type 1 MI, 639 075 patients with type 2 MI, and 43 335 patients with TS were identified. Cardiac arrest, ventricular fibrillation, and ventricular tachycardia were more prevalent in type 1 MI (4.02%, 3.2%, and 7.2%, respectively) compared with both type 2 MI (2.8%, 0.8%, and 5.4% respectively) and TS (2.7%, 1.8%, and 5.3%, respectively). Risk of mortality was lower in TS compared with both type 1 MI (3.3% versus 7.9%; adjusted odds ratio [OR], 0.3; P<0.001) and type 2 MI (3.3% versus 8.2%; adjusted OR, 0.3; P<0.001). Mortality rate (OR, 1.2; P<0.001) and cardiac-cause 30-day readmission rate (adjusted OR, 1.7; P<0.001) were higher in type 1 MI than in type 2 MI. Conclusions Patients with type 1 MI had the highest rates of in-hospital mortality and cardiac-cause 30-day readmission. Risk of all-cause 30-day readmission was highest in patients with type 2 MI. The risk of ventricular arrhythmias in patients with TS is lower than in patients with type 1 MI but higher than in patients with type 2 MI.

1108 PERI-PROCEDURAL COMPLICATIONS AND LONG-TERM OUTCOMES IN ATRIAL FIBRILLATION PATIENTS STRATIFIED FOR CHRONIC KIDNEY DISEASE SEVERITY UNDERGOING LEFT ATRIAL APPENDAGE OCCLUSION: RESULTS FROM AN INTERNATIONAL, MULTICENTRE REGISTRY

Background

Atrial fibrillation (AF) and chronic kidney disease (CKD) often coexist and share an increased risk of thromboembolic events. CKD concomitantly contributes to several pathophysiological changes predisposing towards a pro-haemorrhagic state.

Objective

To evaluate the impact of kidney function on peri-procedural complications and clinical outcomes in AF patients undergoing left atrial appendage occlusion (LAAO) with a Watchman device.

Methods

2124 consecutive AF patients undergoing Watchman implantation at 8 different centers were categorized into CKD stage 1+2 (n=1089), CKD stage 3 (n=796), CKD stage 4 (n=170), CKD stage 5 (n=69) based on the estimated glomerular filtration rate at baseline. The primary efficacy endpoint included a composite of cardiovascular (CV) mortality, stroke, transient ischemic attack, peripheral thromboembolism (TE), and major bleeding.

Results

A non-significant higher incidence of major peri-procedural adverse events (1.7% vs. 2.3% vs. 4.1% vs. 4.3%) was observed with worsening baseline kidney function (p=0.14). The mean follow-up period was 13 ± 7 months [2226 patient-years (PY)]. In comparison to CKD stage 1+2 as a reference, the incidence of the primary endpoint was significantly higher in CKD stage 3 (log-rank p-value= 0.04), CKD stage 4 (log-rank p-value= 0.01), and CKD stage 5 (log-rank p-value= 0.001). A non-significant increase in event rates for stroke/TIA and clinically relevant bleeding was observed among the four groups. LAAO led to a TE risk reduction of 72%, 66%, 62%, and 41% in each group. The relative risk reduction in the incidence of major bleeding was 58%, 44%, 51%, and 52%, respectively.

Conclusion

Patients with moderate-to-severe CKD had a higher incidence of the primary composite endpoint. The relative risk reduction in the incidence of TE and major bleeding was consistent across CKD groups, irrespective of the very different risk profiles at baseline.

Prospective observational study investigating the predictive validity of the STarT Back tool and the clinical effectiveness of stratified care in an emergency department setting

PURPOSE

To determine the predictive validity of the STarT Back tool (SBT) undertaken at baseline and 6 weeks to classify Emergency Department (ED) patients with LBP into groups at low, medium or high risk of persistent disability at 3 months. A secondary aim was to evaluate the clinical effectiveness of pragmatic risk-matched treatment in an ED cohort at 3 months.

METHODS

A prospective observational multi-centre study took place in the physiotherapy services linked to the ED in four teaching hospitals in Dublin, Ireland. Patients were stratified into low, medium and high-risk groups at their baseline assessment. Participants received stratified care, where the content of their treatment was matched to their risk profile. Outcomes completed at baseline and 3 months included pain and disability. Linear regression analyses assessed if baseline or 6-week SBT score were predictive of disability at 3 months. Changes in the primary outcome of disability were dichotomised into those who achieved/ did not achieve a 30% improvement in their RMDQ at 6 weeks and 3 months.

RESULTS

The study enrolled 118 patients with a primary complaint of LBP ± leg pain with 67 (56.7%) completing their 6-week and 3-month follow-up. Baseline RMDQ and being in medium or high risk SBT group at 6 weeks were predictive of persistent disability at 3 months. A total of 54 (80.6%) participants reported a > 30% improvement at 3 months.

CONCLUSION

Disability at baseline and SBT administered at 6 weeks more accurately predicted disability at 3 months than SBT at baseline in an ED population.

The genetic spectrum of hypertrophic cardiomyopathy in an irish cohort

Background

Hypertrophic cardiomyopathy (HCM) has long been described as the archetypal monogenic cardiac disease. It fulfils the criteria for Mendelian inheritance and painstaking early co-segregation studies by Seidman et al in 1990 lead to the discovery that mutations in MYH7 cause HCM. From here, the genetic architecture of HCM has been gradually assembled and thousands of individual mutations discovered. The complexity of HCM genetics continues to evolve to include the gene-negative cohort and those carrying multiple mutations. We sought to describe the genetic spectrum of HCM in an Irish population.

Methods

A retrospective examination of the proband database of a specialist cardiomyopathy clinic was undertaken to select all patients with gene-positive HCM. Their clinical data and cardiac imaging was reviewed. Mutations classified by the American College of Medical Genetics as Class 4 and 5 were considered pathogenic. Variants of uncertain significance (VUS) in candidate genes were also recorded, though not clinically actionable.

Results

The results of genetic testing for 254 HCM patients were reviewed. 94% of patients (n=238) had a single pathogenic HCM gene mutation. 5% of patients (n=13) had digenic disease. The remaining 1% (n=3) had oligogenic disease. MYBPC3 was the most commonly involved gene with 116 patients (45.6%) carrying a pathogenic variant. The p. Arg502Trp missense mutation is the most common mutation observed within the Irish cohort and has a founder effect in England. MYH7 mutations were found in 51 patients (20%). Troponin mutations were found in 20 patients (6.8%). Although formally classified as a VUS, there was an overrepresentation of FHOD3 mutations with 19 patients (7.4%) carrying a variant. 41 patients (16%) had pathogenic mutations in PRKAG2, LAMP2 and mitochondrial genes collectively.

Discussion

This Irish cohort has a similar genetic profile in sarcomeric HCM to published European registry data. There is an overrepresentation in HCM phenocopy/metabolic conditions such as mitochondrial and PRKAG2-associated cardiomyopathy. This represents a genetically homogenous small population in Ireland but also includes one of the largest Danon disease cohorts in Europe.

The genetic architecture of hypertrophic cardiomyopathy is complex and the concept of monogenic sarcomeric disease is an over-simplification. There is significant phenotypic variability due to gene-gene effects and gene-dose effects, as well as elusive epigenetic modifier effects. Our understanding of the genetic complexities continues to evolve.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): The Mater Foundation

Promise or peril: the ECG in HCM

Introduction

Hypertrophic cardiomyopathy is a complex disease of the myocardium characterised by left ventricular hypertrophy &gt;15mm in any one segment, in the absence of loading conditions. The phenotypic variability and inhomogeneous nature of the condition have resulted in difficulties with diagnosis. Despite the significant progression in cardiac imaging and genetics, the electrocardiogram (ECG) remains the cornerstone of initial evaluation of patients with HCM and in the screening of families. Moreover, the ECG is in widespread use for pre-participation sports screening.

Purpose

Original and contemporary studies indicate that the ECG is normal in only 6–10% of patients with echocardiographic evidence of HCM. We hypothesised that the ECG may be normal in a significant proportion of HCM patients. This study sought to reassess the ECG as a screening tool in a HCM cohort.

Methods

112 patients were selected randomly from the database of a specialist cardiomyopathy clinic. Their most recent ECG, clinical and imaging data were reviewed. All patients had echocardiographic HCM and were carriers of pathogenic sarcomere gene mutations. Patients with phenocopies were excluded. ECG data for 100 age and sex-matched controls was also analysed. ECG interpretation was performed using international criteria.

Results

18% of patients with a clinical diagnosis of HCM by conventional diagnostic standards (LV wall thickness &gt;15mm) had a normal ECG. A further 7% had a normal ECG with a mild HCM phenotype (LV wall thickness of 13–14mm). The most common abnormality observed was T wave inversion (TWI) in 28%. An additional unexpected finding in the HCM group was isolated TWI in lead aVL. This occurred in 27% of patients in the absence of any other repolarisation abnormalities, compared with 1% of controls. The significance of this finding is unclear. 27% of HCM patients displayed voltage criteria for left ventricular hypertrophy by either Cornell or Sokolow-Lyon criteria, with just 4% meeting criteria for both. 13% of HCM patients had corrected QT prolongation, in the absence of medications responsible for this.

Conclusion

The ECG continues to play a pivotal role in HCM diagnosis but its sensitivity to detect disease has been over-estimated. Up to a quarter of patients with HCM have a normal ECG. This is significantly higher than previously reported. The ECG in isolation therefore is not a reliable tool for screening for HCM in the general population and especially unreliable in at-risk subjects.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): The Mater Foundation

Outcomes of Patients Hospitalized With Cardiovascular Implantable Electronic Device-Related Infective Endocarditis, Prosthetic Valve Endocarditis, and Native Valve Endocarditis: A Nationwide Study, 2003 to 2017

Background

Most published reports describing outcomes of patients with cardiovascular implantable electronic device–related infective endocarditis (CIED‐IE) are single‐center studies with small patient sample sizes. The goal of this study was to utilize population‐based data to assess trends in CIED‐IE hospitalization and to compare outcomes between patients hospitalized with CIED‐IE, prosthetic valve endocarditis (PVE), and native valve endocarditis (NVE).

Methods and Results

A query of the National (Nationwide) Inpatient Sample (NIS) database between 2003 and 2017 identified 646 325 patients hospitalized with infective endocarditis in the United States of whom 585 974 (90%) had NVE, 27 257 (4.2%) had CIED‐IE, and 26 111 (4%) had PVE.

There was a 509% increase in CIED‐IE hospitalizations in the United States from 2003 to 2017 (P trend<0.001). In‐hospital mortality and length of stay associated with CIED‐IE decreased during the study period from 15% and 20 days in 2003 to 9.7% and 19 days in 2017 (P trend=0.032 and 0.018, respectively). The in‐hospital mortality rate was lower in patients hospitalized with CIED‐IE (9.2%) than in patients with PVE (12%) and NVE (12%). Length of stay was longest in the CIED‐IE group (17 compared with 14 days for both NVE and PVE). Hospital costs were highest for the CIED‐IE group ($56 000 compared with $37 000 in NVE and $45 000 in PVE).

Conclusions

Despite the fact that the number of comorbidities per patient with CIED‐IE increased during the study period, mortality rate and hospital length of stay decreased. The mortality rate was significantly lower for patients with CIED‐IE than for patients with NVE and PVE. Patients with CIED‐IE had the longest lengths of stay and highest hospital costs.

P95 PERI–PROCEDURAL COMPLICATIONS AND LONG–TERM OUTCOMES IN ATRIAL FIBRILLATION PATIENTS STRATIFIED FOR CHRONIC KIDNEY DISEASE SEVERITY UNDERGOING LEFT ATRIAL APPENDAGE OCCLUSION: RESULTS FROM AN INTERNATIONAL, MULTICENTER REGISTRY

Background

Atrial fibrillation (AF) and chronic kidney disease (CKD) often coexist and share an increased risk of thromboembolic events. CKD concomitantly contributes to several pathophysiological changes predisposing towards a pro–haemorrhagic state.

Objective

To evaluate the impact of kidney function on peri–procedural complications and clinical outcomes in AF patients undergoing left atrial appendage occlusion (LAAO) with a Watchman device.

Methods

2124 consecutive AF patients undergoing Watchman implantation at 8 different centers were categorized into CKD stage 1 + 2 (n = 1089), CKD stage 3 (n = 796), CKD stage 4 (n = 170), CKD stage 5 (n = 69) based on the estimated glomerular filtration rate at baseline. The primary efficacy endpoint included a composite of cardiovascular (CV) mortality, stroke, transient ischemic attack, peripheral thromboembolism (TE), and major bleeding.

Results

A non–significant higher incidence of major peri–procedural adverse events (1.7% vs. 2.3% vs. 4.1% vs. 4.3%) was observed with worsening baseline kidney function (p = 0.14). The mean follow–up period was 13 ± 7 months [2226 patient–years (PY)]. In comparison to CKD stage 1 + 2 as a reference, the incidence of the primary endpoint was significantly higher in CKD stage 3 (log–rank p–value= 0.04), CKD stage 4 (log–rank p–value= 0.01), and CKD stage 5 (log–rank p–value= 0.001) (Fig. 1A). A non–significant increase in event rates for stroke/TIA and clinically relevant bleeding was observed among the four groups. LAAO led to a TE risk reduction of 72%, 66%, 62%, and 41% in each group (Fig. 1B). The relative risk reduction in the incidence of major bleeding was 58%, 44%, 51%, and 52%, respectively (Fig. 1C).

Conclusion

Patients with moderate–to–severe CKD had a higher incidence of the primary composite endpoint. The relative risk reduction in the incidence of TE and major bleeding was consistent across CKD groups, irrespective of the very different risk profiles at baseline.

Pulmonary tuberculosis in intensive care setting, with a focus on the use of severity scores, a multinational collaborative systematic review

Background and aim

Tuberculosis (TB) is associated with a high mortality in the intensive care unit (ICU), especially in subjects with Acute Respiratory Distress Syndrome (ARDS) requiring mechanical ventilation. Despite its global burden on morbidity and mortality, TB is an uncommon cause of ICU admission, however mortality is disproportionate to the advances in diagnosis and treatment made. Herein we report a systematic review of published studies.

Methods

Our Literature search was conducted to identify studies on outcomes of individuals with TB admitted to ICU. We report and review in-hospital mortality, predictors of poorer outcomes, usefulness of severity scoring systems and potential benefits of intravenous antibiotics. Searches from Pubmed, Embase, Cochrane and Medline were conducted from inception to March 2020. Only literature in English was included.

Results

Out of 529 potentially relevant articles, 17 were included. Mortality across all studies ranged from 29-95% with an average of 52.9%. All severity scores underestimated average mortality. The most common indication for ICU admission was acute respiratory failure (36.3%). Negative predictors of outcome included hospital acquired infections, need of mechanical ventilation and vasopressors, delay in initiation of anti-TB treatment, more than one organ failure and a higher severity score. Low income, high incidence countries showed a 23.4% higher mortality rate compared to high income, low TB incidence countries.

Conclusion

Mortality in individuals with TB admitted to ICU is high. Earlier detection and treatment initiation is needed.

Incidence of carditis and predictors of pacemaker implantation in patients hospitalized with Lyme disease

BACKGROUND

Lyme carditis, defined as direct infection of cardiac tissue by Borrelia bacteria, affects up to 10% of patients with Lyme disease. The most frequently reported clinical manifestation of Lyme carditis is cardiac conduction system disease. The goal of this study was to identify the incidence and predictors of permanent pacemaker implantation in patients hospitalized with Lyme disease.

METHODS

A retrospective cohort analysis of the Nationwide Inpatient sample was performed to identify patients hospitalized with Lyme disease in the US between 2003 and 2014. Patients with Lyme carditis were defined as those hospitalized with Lyme disease who also had cardiac conduction disease, acute myocarditis, or acute pericarditis. Patients who already had pacemaker implants at the time of hospitalization (N = 310) were excluded from the Lyme carditis subgroup. The primary study outcome was permanent pacemaker implantation. Secondary outcomes included temporary cardiac pacing, permanent pacemaker implant, and in-hospital mortality.

RESULTS

Of the 96,140 patients hospitalized with Lyme disease during the study period, 10,465 (11%) presented with Lyme carditis. Cardiac conduction system disease was present in 9,729 (93%) of patients with Lyme carditis. Permanent pacemaker implantation was performed in 1,033 patients (1% of all Lyme hospitalizations and 11% of patients with Lyme carditis-associated conduction system disease). Predictors of permanent pacemaker implantation included older age (OR: 1.06 per 1 year; 95% CI:1.05-1.07; P<0.001), complete heart block (OR: 21.5; 95% CI: 12.9-35.7; P<0.001), and sinoatrial node dysfunction (OR: 16.8; 95% CI: 8.7-32.6; P<0.001). In-hospital mortality rate was higher in patients with Lyme carditis (1.5%) than in patients without Lyme carditis (0.5%).

CONCLUSIONS

Approximately 11% of patients hospitalized with Lyme disease present with carditis, primarily in the form of cardiac conduction system disease. In this 12-year study, 1% of all hospitalized patients and 11% of those with Lyme-associated cardiac conduction system disease underwent permanent pacemaker implantation.

Diagnostic yield from cardiac gene panel testing for inherited cardiac conditions in a large Irish cohort

Background

Inherited cardiomyopathies (hypertrophic, dilated and arrhythmogenic) and cardiac ion channelopathies (long QT, Brugada and CPVT) predispose to sudden cardiac death/sudden arrhythmic death syndrome. Given their genetically heterogenous nature, multi-gene DNA sequencing panels are useful to aid genetic diagnosis.

Purpose

Investigate the diagnostic yield from cardiac gene panel testing undertaken in patients (including molecular autopsy in deceased patients) referred to four clinical services from 2002 to 2020.

Methods

Data was collected by interrogation of departmental databases, family charts, and review of molecular genetic diagnostic reports.

Results

We evaluated molecular genetic diagnostic results from 835 individuals (461 males, 374 females) from 824 families, including 58 deceased patients who underwent molecular autopsy. The median age of the cohort was 44 years (range 0.1–86 years).

Testing for hypertrophic cardiomyopathy (HCM) and long QT syndrome (LQT) genes represented 36% and 32% of the cohort, respectively, with the remaining 32% accounting for other cardiomyopathies, arrhythmia syndromes or metabolic/syndromic diseases. The overall variant detection rate was 50% across all panel types. Three hundred and fifty patients (42%) carried a single variant, 68 patients (8%) carried multiple variants (up to a maximum of four), including two individuals who carried two actionable (pathogenic/likely pathogenic) variants each and 30 individuals (5%) with one actionable variant plus a variant of uncertain significance (VUS).

The overall diagnostic yield of at least one actionable variant was 28%. At least one VUS was detected in 27% of the cohort. Molecular autopsy yielded an actionable variant in 10% of patients, while 30% of the subcohort carried at least one VUS (up to maximum of two).

We found a positive association between female sex and the likelihood of detecting an actionable variant. By decade of age, detection of actionable variants ranged from 19% (60–69 years) to 41% (0–9 years). By panel type, actionable variants ranged from 14% (Brugada) to 35% (cardiomyopathy). The burden of VUS ranged from 22% (LQT) to 46% (dilated cardiomyopathy).

Altogether 234 actionable variants were detected in 26 genes, including seven metabolic or syndromic disease genes. From those with non-metabolic/syndromic forms of disease, 84% of actionable variants were detected in well established ICC genes. Analysis of gene-disease associations for VUS detected from HCM and LQT panels revealed that 10–25% were detected in genes now deemed to have only moderate or limited evidence of disease causation.

Conclusion

Most actionable variants in this cohort were detected in well-established ICC genes, suggesting that large gene panels offer little extra sensitivity compared to historic smaller gene panels. Despite recent gene curation efforts, the high burden of VUS remains a considerable challenge in ICC management.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): National Children's Research Centre

1266Novel formin homology 2 domain containing 3 (FHOD3) mutations associated with the pathogenesis of hypertrophic cardiomyopathy (HCM) in an Irish population

Background

The genetic cause of hypertrophic cardiomyopathy (HCM) remains unexplained in a substantial proportion of cases. Recent large sequencing studies suggest that, though not previously implicated, FHOD3 (a Formin protein responsible for sarcomere assembly) may have a role in the pathogenesis of HCM, particularly variants affecting a conserved small coil-coiled domain (amino acids 622 to 655).

Aim

To investigate the relationship between novel FHOD3 mutations, previously classified as variants of uncertain significance (American College of Medical Genetics ACMG Class III), and the development of HCM. 

Methods

A single center review of HCM probands carrying mutations in the FHOD3 gene was conducted. Existing HCM patients from the family heart screening clinic database were retrospectively reviewed. Frequency of FHOD3 mutations, segregation among family members and clinical characteristics of patients were reviewed. All genetic analysis was conducted via the same internationally validated next generation sequencing lab.

Results

Of 367 HCM probands identified in our center, 9 (2.45%) were found to have ACMG Class III mutations affecting the FHOD3 gene. Five of these 9 probands (56%) displayed the same p.Arg637Gln mutation, while the remaining 4 (44%) carry the same p.Ile648Thr residue alteration. Both of these are rare mutations, found to be present in &lt;1% of controls in previous large sequencing studies and not previously reported. Among probands with the p.Ile648Thr mutation, co-segregation was confirmed in one family, another first-degree relative in the same family having suffered a sudden cardiac death (HCM confirmed on autopsy). In those with the p.Arg367Gln mutation, a strong family history was observed in two separate families, 4 first-degree members having a confirmed HCM diagnosis. Carriers of both mutation types displayed varying degrees of disease severity with rates of non-sustained ventricular tachycardia and device implantation similar to other HCM cohorts (∼40%).

Conclusions

FHOD3 is a novel gene, recently implicated in the pathogenesis of HCM, though not previously well described in the literature. Carrier frequency of FHOD3 mutations in the HCM population in our center is similar to that described in recent publication (1-2%), and all carry variants affecting the suspected small coil-coiled domain (amino-acids 622-625).

P333Left atrial function by echocardiography is independent of degree of left atrial electrical scar

Introduction

Assessment of left atrial function via transthoracic echocardiography (TTE) is performed most commonly by measuring the transmitral A wave in sinus rhythm. Left atrial (LA) fibrosis plays an important role in the pathogenesis and perpetuation of Atrial Fibrillation (AF). It may be identified by bipolar voltage (BiV) mapping, which can easily be performed at the beginning of a Pulmonary Vein Isolation (PVI) procedure. The relationship between the degree of LA fibrosis, characterised with mapping, and LA function, determined by echocardiography, has not previously been elucidated.

Methods

Patients were enrolled in a project to evaluate the degree of fibrosis during PVI procedures. Pre-procedure TTEs of those presenting in sinus rhythm were assessed and the transmitral A wave was measured and compared to the degree of scarring seen. The high density electroanatomic maps (HD-EAMs) created during the PVIs were analysed using a novel VHA algorithm after the procedure. All points with voltages &lt; 0.5mV were defined to have electrical scar. Patients were classified into 4 quartiles based on the levels of scar seen (Figure 1).

Results

39 patients were included in the evaluation. Average age was 60.6 +/- 13.2 years. 32 (82.0%) of the patients were male. Mean CHADS2VASc score was 1.5. The mean percentage of scar was calculated as 19.6 +/- 15.9%. The average A wave was 0.62 +/- 0.18 ms-1. Pearson’s correlation coefficient showed no relationship between LA scar and either A wave velocities (r = 0.26, p = 0.11) or E:A ratio (r=-0.02, p = 0.91). A significant correlation between A wave velocity and CHADS2VASc was observed (r = 0.49, p = 0.001).

Conclusion

Our study demonstrates no relationship between degree of LA scarring and reduced LA function on TTE as assessed by the A wave. It has been established that structural remodelling in AF (such as atrial dilatation) may occur independently of the electrical remodelling. A potential explanation for our findings is that the electrical scarring in AF, which results in alterations in refractory periods, precedes the negative remodelling which ultimately results in reduced atrial function. This hypothesis would need to be further evaluated in larger studies.

Abstract Figure 1

1269The SADS heart of the matter: a review of the sudden arrhythmic death syndrome (SADS) biobank - the cornerstone of a national strategy

Background

Sudden cardiac death (SCD) in the young (age 1-35) is commonly attributed to structural and arrhythmogenic syndromes, for which there is often an underlying genetic basis. Expert recommendation emphasises the importance of genetic testing in such cases, however to date this remains the first and only national programme in Europe to facilitate this. 

Aim

 To review detection rates of genetic variants in samples tested via the SADS BioBank and possibly demonstrate the merits of this novel resource for primary prevention for family members.

Methods

 Family screening and consent for genetic testing was carried out in the Family Heart Screening Clinic. Result analysis of samples sent for molecular autopsy via the BioBank from its induction in January 2015 was performed. Genetic analysis was conducted via the same internationally accredited next generation sequencing lab.

Results

 From January 2015 to July 2019, 161 samples had been stored in the SADS BioBank following confirmed SADS death on autopsy; 33% female and 67% male. Of these, 24 (14.9%) samples were sent for genetic testing: 21 for a 380 gene molecular autopsy and 3 for a targeted hypertrophic cardiomyopathy panel (173 genes). Of 24 samples tested, 10 (42%) yielded positive genetic variants: 4 American College of Medical Genetics (ACMG) Class IV or V mutations considered pathogenic, and 6 ACMG class III variants of uncertain significance (VUS). Familial cascade screening following confirmed pathogenic mutations resulted in detection of 3 (33.3%) positive genotypes in 9 first-degree relatives. Screening of relatives of Class III positive probands resulted in diagnosis of an Inherited Cardiac Condition (ICC) in 25% of first-degree relatives. 8.2% of first-degree relatives of probands with negative gene testing were given an ICC diagnosis following clinical screening.

Conclusions

 This short study demonstrates the unique potential the SADS BioBank has to offer in terms of identifying those most at risk and optimising prevention strategies for relatives, thus highlighting the role for such a resource in terms of preventative screening in the future.

Pathogenic Variant (ACMG Class IV & V) Variant of Uncertain Significance(ACMG Class III) No Gene Variant Identified Number Detected (n = 24) 4 6 14 1st Degree Relatives Screened (n = 86) 17 20 49 2nd Degree Relatives Screened (n = 46) 4 23 19 Genotype Detected (n = 4) 3 1 0 Phenotype Detected (n = 10) 1 5 4 Breakdown of clinical and genetic results of family screening by ACMG class.

Abstract Figure.

Gastric Aspiration and Its Role in Airway Inflammation

Gastro-Oesophageal Reflux (GOR) has been associated with chronic airway diseases while the passage of foreign matter into airways and lungs through aspiration has the potential to initiate a wide spectrum of pulmonary disorders. The clinical syndrome resulting from such aspiration will depend both on the quantity and nature of the aspirate as well as the individual host response. Aspiration of gastric fluids may cause damage to airway epithelium, not only because acidity is toxic to bronchial epithelial cells but also due to the effect of digestive enzymes such as pepsin and bile salts. Experimental models have shown that direct instillation of these factors to airways epithelia cause damage with a consequential inflammatory response. The pathophysiology of these responses is gradually being dissected, with better understanding of acute gastric aspiration injury, a major cause of acute lung injury, providing opportunities for therapeutic intervention and potentially, ultimately, improved understanding of the chronic airway response to aspiration. Ultimately, clarification of the inflammatory pathways which are related to micro-aspiration via pepsin and bile acid salts may eventually progress to pharmacological intervention and surgical studies to assess the clinical benefits of such therapies in driving symptom improvement or reducing disease progression.

A Retrospective Audit of In-Hospital 30-day Mortality from Acute Myocardial Infarction in Connolly Hospital Blanchardstown

In 2015, The Department of Health published the first annual report of the "National Healthcare Quality Reporting System." Connolly Hospital was reported to a mortality rate within 30 days post-Acute Myocardial Infarction (AMI) of 9.87 per 100 cases which was statistically significantly higher than the national rate. We carried out a retrospective audit of patients who were HIPE-coded as having died within 30 days of AMI from 2011-2013 and identified 42 patients. On review, only 23 patients (54.8%) were confirmed as having had an AMI. We identified 12 patients who had AMI included on death certificate without any evidence for same. If the 22 patients incorrectly coded were excluded, the mortality rate within 30 days post-AMI in CHB would fall to 4.14 deaths per 100 cases, well below the national average. Inaccuracies of data collection can lead to erroneous conclusions when examining healthcare data.

Left cardiac sympathetic denervation: case series and technical report

BACKGROUND

Left cardiac sympathetic denervation (LCSD) is a surgical procedure that has been shown to have an antiarrhythmic and antifibrillatory effect. Evidence indicating its antiarrhythmic effect has been available for over 100 years. It involves the removal of the lower half of the stellate ganglion and T2-T4 of the sympathetic ganglia and is carried out as either a unilateral or bilateral procedure. With advancements in thoracic surgery, it can be safely performed via a minimally invasive Video-Assisted Thoracoscopic Surgery (VATS) approach resulting in significantly less morbidity and a shortened inpatient stay. LCSD provides a valuable treatment option for patients with life-threatening channelopathies and cardiomyopathies.

AIMS AND METHODS

This case series reports the preliminary paediatric and adult experience in the Republic of Ireland with LCSD and describes five cases recently treated in addition to an outline of the operative procedure employed. Of the five cases included, two were paediatric cases and three were adult cases.

RESULTS

One of the paediatric patients had a diagnosis of the rare catecholaminergic polymorphic ventricular tachycardia (CPVT) and the other a diagnosis of long-QT syndrome. Both paediatric patients experienced excellent outcomes. Of the three adult patients, two benefitted greatly and remain well at follow-up (one inappropriate sinus tachycardia and one CPVT). One patient with idiopathic ventricular fibrillation unfortunately passed away from intractable VF despite all attempts at resuscitation.

CONCLUSION

In this case series, we highlight that LCSD provides a critical adjunct to existing medical therapies and should be considered for all patients with life-threatening refractory arrhythmias especially those patients on maximal medical therapy.

Mental health nursing students' experiences of stress during training: a thematic analysis of qualitative interviews

ACCESSIBLE SUMMARY

What is known on the subject? Stress can impact students on mental health nurse training. This can have implications at the individual level (e.g. their own mental health) and at the level of the organization (e.g. sickness absence and attrition). What this paper adds to existing knowledge? We interviewed 12 mental health nursing students regarding the stress they experienced during training. Participants described how the academic demands can at times be unbearable during clinical placements. There were also issues with 'being a student' on some placements, with participants describing negative attitudes towards them from staff. The younger participants reported feeling overwhelmed on their initial placements and described some of the main challenges of mental health work for them. Raising concerns about the quality of care on wards was also described as particularly challenging for the students. What are the implications for practice? This paper can be useful to help training providers support mental health nursing students. Recommendations include reducing academic demands during clinical placements and extending and promoting existing support services beyond normal 9 am-5 pm working hours, even if these services are limited. Younger students could be better supported by being allocated to the more well-resourced placements in the early stages of their training. Raising awareness among staff of the tasks students can and cannot perform can help improve staff/student relations. Finally, students should be educated about the issues around raising concerns on placements to help the government's drive for a more open and transparent National Health Service (NHS).

INTRODUCTION

Previous studies investigating stress in nursing students focus on general nursing students or adopt quantitative measures.

PURPOSE OF STUDY

A qualitative study focusing specifically on mental health nursing students is required.

METHOD

One-to-one interviews were carried out with mental health nursing students (n = 12). Data were thematically analysed.

RESULTS

Participants reported unreasonable demands during clinical blocks, and described how control/support is lowest on placements with staff shortages. Negative attitudes towards students from staff and related issues were also discussed. Younger participants described struggling with mental health work during the early stages of training.

DISCUSSION

Training providers should strive to provide adequate support to students to help them manage stress during training. Implications for practice Academic demands should be reasonable during clinical blocks and support services outside normal working hours should be available for students, even if these are limited in scope. Greater consideration to the allocation of placements for younger students in the mental health branch could be helpful. Furthermore, staff on placements should be aware of the tasks students can and cannot perform, to help improve staff/student relations. Educating students on the issues of raising concerns can help the government's drive for a more open and transparent National Health Service (NHS).

The effect of the transducers on paediatric thresholds estimated with auditory steady-state responses

The objective of this study was to investigate the usefulness of auditory steady-state responses (ASSRs) for estimating hearing thresholds in young children, compared with behavioural thresholds. The second objective was to investigate ASSR thresholds obtained with insert earphones versus supra-aural headphones to determine which transducer produces ASSR thresholds most similar to behavioural thresholds measured with supra-aural headphones. This retrospective study included 29 participants (58 ears): 12 children (24 ears) in the insert group and 17 children (34 ears) in the supra-aural group. No general anaesthesia was used. For both groups, there was a strong correlation between behavioural and ASSR thresholds, with a stronger correlation for the insert group. When behavioural thresholds are difficult to obtain, ASSR may be a useful objective measure that can be combined with other audiometric procedures to estimate hearing thresholds and to determine appropriate auditory rehabilitation approaches.