X marks the spot: catheter aspiration using the Inari FlowTriever device to debulk defibrillator lead vegetations prior to transvenous lead extraction-a case report.

Background: When cardiac implantable electronic device infection occurs, standard therapy is usually total system extraction. Transvenous lead extraction is preferable to open heart surgical extraction, unless contraindicated because of the presence of very large vegetations on the intravenous leads according to the European Society of Cardiology guidelines. Extraction of transvenous leads with vegetations risks distal embolism resulting in obstruction and/or infection in the pulmonary arteries. Catheter aspiration of vegetations or thrombi has been performed prior to transvenous lead extraction using a partial veno-venous extracorporeal bypass circuit. We report the use of a single-access aspiration system using the Inari FlowTriever 24 French system to debulk a defibrillator lead before percutaneous extraction. Case summary: A 79-year-old male presented with fever 18 years after his first implantable cardioverter defibrillator implant and 9 years after his most recent pulse generator change. Two large vegetations were identified on his transvenous defibrillator lead on the atrial aspect, near the tricuspid annulus, which were aspirated using the Inari Medical 24Fr FlowTriever aspiration catheter. We describe anatomical considerations during the approach and a technique to localize the vegetations based on a combination of fluoroscopy and transoesophageal echocardiogram guidance. Discussion: This case demonstrates the safe and effective use of the Inari Medical 24Fr FlowTriever aspiration catheter in debulking a defibrillator lead before transvenous lead extraction. This method uses a single venous puncture and is not dependent on extracorporeal bypass. Apart from reducing complexity, this technique may be advantageous in patients where anticoagulation needs to be minimised.

Social Determinants of Health Including Child Opportunity Index Leading to Gaps in Care for Patients With Significant Congenital Heart Disease.

BACKGROUND: Gaps in care (GIC) are common for patients with congenital heart disease (CHD) and can lead to worsening clinical status, unplanned hospitalization, and mortality. Understanding of how social determinants of health (SDOH) contribute to GIC in CHD is incomplete. We hypothesize that SDOH, including Child Opportunity Index (COI), are associated with GIC in patients with significant CHD. METHODS AND RESULTS: A total of 8554 patients followed at a regional specialty pediatric hospital with moderate to severe CHD seen in cardiology clinic between January 2013 and December 2015 were retrospectively reviewed. SDOH factors including race, ethnicity, language, and COI calculated based on home address and zip code were analyzed. GIC of >3.25 years were identified in 32% (2709) of patients. GIC were associated with ages 14 to 29 years (P<0.001), Black race or Hispanic ethnicity (P<0.001), living ≥150 miles from the hospital (P=0.017), public health insurance (P<0.001), a maternal education level of high school or less (P<0.001), and a low COI (P<0.001). Multivariable analysis showed that GIC were associated with age ≥14 years, Black race or Hispanic ethnicity, documenting <3 caregivers as contacts, mother's education level being high school or less, a very low/low COI, and insurance status (C statistic 0.66). CONCLUSIONS: One-third of patients followed in a regional referral center with significant CHD experienced a substantial GIC (>3.25 years). Several SDOH, including a low COI, were associated with GIC. Hospitals should adopt formal GIC improvement programs focusing on SDOH to improve continuity of care and ultimately overall outcomes for patients with CHD.

Adaptation of Left Ventricular Twist Mechanics in Exercise-Trained Children Is Only Evident after the Adolescent Growth Spurt.

BACKGROUND: The extent of structural cardiac remodeling in response to endurance training is maturity dependent. In adults, this structural adaptation is often associated with the adaptation of left ventricular (LV) twist mechanics. For example, an increase in LV twist often follows an expansion in end-diastolic volume, whereas a reduction in twist may follow a thickening of the LV walls. While structural cardiac remodeling has been shown to be more prominent post-peak height velocity (PHV), it remains to be determined how this maturation-dependent structural remodeling influences LV twist. Therefore, we aimed to (1) compare LV twist mechanics between trained and untrained children pre- and post-PHV and (2) investigate how LV structural variables relate to LV twist mechanics pre- and post-PHV. METHODS: Left ventricular function and morphology were assessed (echocardiography) in endurance-trained and untrained boys (n = 38 and n = 28, respectively) and girls (n = 39 and n = 34, respectively). Participants were categorized as either pre- or post-PHV using maturity offset to estimate somatic maturation. RESULTS: Pre-PHV, there were no differences in LV twist or torsion between trained and untrained boys (twist: P = .630; torsion: P = .382) or girls (twist: P = .502; torsion: P = .316), and LV twist mechanics were not related with any LV structural variables (P > .05). Post-PHV, LV twist was lower in trained versus untrained boys (P = .004), with torsion lower in trained groups, irrespective of sex (boys: P < .001; girls: P = .017). Moreover, LV torsion was inversely related to LV mass (boys: r = -0.55, P = .001; girls: r = -0.46, P = .003) and end-diastolic volume (boys: r = -0.64, P < .001; girls: r = -0.36, P = .025) in both sexes. CONCLUSIONS: A difference in LV twist mechanics between endurance-trained and untrained cohorts is only apparent post-PHV, where structural and functional remodeling were related.

The influence of training status and parasympathetic blockade on the cardiac rate, rhythm, and functional response to autonomic stress.

Apnea (breath-holding) elicits co-activation of sympathetic and parasympathetic nervous systems, affecting cardiac control. In situations of autonomic co-activation (e.g., cold water immersion), cardiac arrhythmias are observed during apnea. Chronic endurance training reduces resting heart rate in part via elevation in parasympathetic tone, and has been identified as a risk factor for development of arrhythmias. However, few studies have investigated autonomic control of the heart in trained athletes during stress. Therefore, we determined whether heightened vagal tone resulting from endurance training promotes a higher incidence of arrhythmia during apnea. We assessed the heart rate, rhythm (ECG lead II), and cardiac inotropic (speckle-tracking echocardiography) response to apnea in 10 endurance trained and 7 untrained participants. Participants performed an apnea at rest and following sympathetic activation using post-exercise circulatory occlusion (PECO). All apneas were performed prior to control (CON) and following vagal block using glycopyrrolate (GLY). Trained participants had lower heart rates at rest (p = 0.03) and during apneas (p = 0.009) under CON. At rest, 3 trained participants exhibited instances of junctional rhythm and 4 trained participants developed ectopy during CON apneas, whereas 3 untrained participants developed ectopic beats only with concurrent sympathetic activation (PECO). Following GLY, no arrhythmias were noted in either group. Vagal block also revealed increased cardiac chronotropy (heart rate) and inotropy (strain rate) during apnea, demonstrating a greater sympathetic influence in the absence of parasympathetic drive. Our results highlight that endurance athletes may be more susceptible to ectopy via elevated vagal tone, whereas untrained participants may only develop ectopy through autonomic conflict.

Differentially Private Occupancy Monitoring from WiFi Access Points.

Accurately monitoring the number of individuals inside a building is vital to limiting COVID-19 transmission. Low adoption of contact tracing apps due to privacy concerns has increased pervasiveness of passive digital tracking alternatives. Large arrays of WiFi access points can conveniently track mobile devices on university and industry campuses. The CrowdMap system employed by the University of Southern California enables such tracking by collecting aggregate statistics from connections to access points around campus. However, since these devices can be used to infer the movement of individuals, there is still a significant risk that even aggregate occupancy statistics will violate the location privacy of individuals. We examine the use of Differential Privacy in reporting statistics from this system as measured using point and range count queries. We propose discretization schemes to model the positions of users given only user connections to WiFi access points. Using this information we are able to release accurate counts of occupants in areas of campus buildings such as labs, hallways, and large discussion halls with minimized risk to individual users' privacy.

Arrhythmogenic cardiomyopathy and differential diagnosis with physiological right ventricular remodelling in athletes using cardiovascular magnetic resonance.

To describe the overlap between structural abnormalities typical of arrhythmogenic right ventricular cardiomyopathy (ARVC) and physiological right ventricular adaptation to exercise and differentiate between pathologic and physiologic findings using CMR. We compared CMR studies of 43 patients (mean age 49 ± 17 years, 49% males, 32 genotyped) with a definitive diagnosis of ARVC with 97 (mean age 45 ± 16 years, 61% males) healthy athletes. CMR was abnormal in 37 (86%) patients with ARVC, but only 23 (53%) fulfilled a major or minor CMR criterion according to the TFC. 7/20 patients who did not fulfil any CMR TFC showed pathological finding (RV RWMA and fibrosis in the LV or LV RWMA). RV was affected in isolation in 17 (39%) patients and 18 (42%) patients showed biventricular involvement. Common RV abnormalities included RWMA (n = 34; 79%), RV dilatation (n = 18; 42%), RV systolic dysfunction (≤ 45%) (n = 17; 40%) and RV LGE (n = 13; 30%). The predominant LV abnormality was LGE (n = 20; 47%). 22/32 (69%) patients exhibited a pathogenic variant: PKP2 (n = 17, 53%), DSP (n = 4, 13%) and DSC2 (n = 1, 3%). Sixteen (16%) athletes exceeded TFC cut-off values for RV volumes. None of the athletes exceeded a RV/LV end-diastolic volume ratio > 1.2, nor fulfilled TFC for impaired RV ejection fraction. The majority (86%) of ARVC patients demonstrate CMR abnormalities suggestive of cardiomyopathy but only 53% fulfil at least one of the CMR TFC. LV involvement is found in 50% cases. In athletes, an RV/LV end-diastolic volume ratio > 1.2 and impaired RV function (RVEF ≤ 45%) are strong predictors of pathology.

The influence of maturation on exercise-induced cardiac remodelling and haematological adaptation.

Cardiovascular and haematological adaptations to endurance training facilitate greater maximal oxygen consumption ( V̇O2max${\dot{V}_{{{\rm{O}}_{\rm{2}}}{\rm{max}}}}$ ), and such adaptations may be augmented following puberty. Therefore, we compared left ventricular (LV) morphology (echocardiography), blood volume, haemoglobin (Hb) mass (CO rebreathing) and V̇O2max${\dot{V}_{{{\rm{O}}_{\rm{2}}}{\rm{max}}}}$ in endurance-trained and untrained boys (n = 42, age = 9.0-17.1 years, V̇O2max${\dot{V}_{{{\rm{O}}_{\rm{2}}}{\rm{max}}}}$  = 61.6 ± 7.2 ml/kg/min, and n = 31, age = 8.0-17.7 years, V̇O2max${\dot{V}_{{{\rm{O}}_{\rm{2}}}{\rm{max}}}}$  = 46.5 ± 6.1 ml/kg/min, respectively) and girls (n = 45, age = 8.2-17.0 years, V̇O2max${\dot{V}_{{{\rm{O}}_{\rm{2}}}{\rm{max}}}}$  = 51.4 ± 5.7 ml/kg/min, and n = 36, age = 8.0-17.6 years, V̇O2max${\dot{V}_{{{\rm{O}}_{\rm{2}}}{\rm{max}}}}$  = 39.8 ± 5.7 ml/kg/min, respectively). Pubertal stage was estimated via maturity offset, with participants classified as pre- or post-peak height velocity (PHV). Pre-PHV, only a larger LV end-diastolic volume/lean body mass (EDV/LBM) for trained boys (+0.28 ml/kg LBM, P = 0.007) and a higher Hb mass/LBM for trained girls (+1.65 g/kg LBM, P = 0.007) were evident compared to untrained controls. Post-PHV, LV mass/LBM (boys: +0.50 g/kg LBM, P = 0.0003; girls: +0.35 g/kg LBM, P = 0.003), EDV/LBM (boys: +0.35 ml/kg LBM, P < 0.0001; girls: +0.31 ml/kg LBM, P = 0.0004), blood volume/LBM (boys: +12.47 ml/kg LBM, P = 0.004; girls: +13.48 ml/kg LBM, P = 0.0002.) and Hb mass/LBM (boys: +1.29 g/kg LBM, P = 0.015; girls: +1.47 g/kg LBM, P = 0.002) were all greater in trained versus untrained groups. Pre-PHV, EDV (R2adj  = 0.224, P = 0.001) in boys, and Hb mass and interventricular septal thickness (R2adj  = 0.317, P = 0.002) in girls partially accounted for the variance in V̇O2max${\dot{V}_{{{\rm{O}}_{\rm{2}}}{\rm{max}}}}$ . Post-PHV, stronger predictive models were evident via the inclusion of LV wall thickness and EDV in boys (R2adj  = 0.608, P < 0.0001), and posterior wall thickness and Hb mass in girls (R2adj  = 0.490, P < 0.0001). In conclusion, cardiovascular adaptation to exercise training is more pronounced post-PHV, with evidence for a greater role of central components for oxygen delivery. KEY POINTS: It has long been hypothesised that cardiovascular adaptation to endurance training is augmented following puberty. We investigated whether differences in cardiac and haematological variables exist, and to what extent, between endurance-trained versus untrained, pre- and post-peak height velocity (PHV) children, and how these central factors relate to maximal oxygen consumption. Using echocardiography to quantify left ventricular (LV) morphology and carbon monoxide rebreathing to determine blood volume and haemoglobin mass, we identified that training-related differences in LV morphology are evident in pre-PHV children, with haematological differences also observed between pre-PHV girls. However, the breadth and magnitude of cardiovascular remodelling was more pronounced post-PHV. Cardiac and haematological measures provide significant predictive models for maximal oxygen consumption ( V̇O2max${\dot{V}_{{{\rm{O}}_{\rm{2}}}{\rm{max}}}}$ ) in children that are much stronger post-PHV, suggesting that other important determinants within the oxygen transport chain could account for the majority of variance in V̇O2max${\dot{V}_{{{\rm{O}}_{\rm{2}}}{\rm{max}}}}$ before puberty.

Now You See It .: When Lead Positions Tell 2 Stories.

The field of heart transplantation has seen considerable innovation over the years. Understanding the wide range of presentations in patients who have undergone operations we now consider historical remains important. This case illustrates the complexities of management in a patient with a previous heart transplant who presented with ventricular tachycardia. (Level of Difficulty: Advanced.).

Arrhythmia in an athlete diagnosed by smartphone electrocardiogram: a case report.

BACKGROUND: This is the first case report demonstrating the use of a smartphone device, enabling the diagnosis of an arrhythmia in the sports cardiology literature. CASE SUMMARY: A 17-year-old semi-professional rugby player presented with recurrent episodes of palpitations terminated by vagal manoeuvres. The rugby player's resting 12-lead electrocardiogram (ECG), echocardiogram, and exercise stress test were normal. Due to his suggestive history and an ECG trace from a smartphone device, demonstrating a narrow complex tachycardia, an electrophysiological study was arranged. The study demonstrated a slow-fast atrioventricular nodal re-entrant tachycardia which was successfully ablated. DISCUSSION: The ambulatory use of a smartphone ECG device assisted in the timely diagnosis and management of an undiagnosed paroxysmal arrhythmia in a rugby player. This resulted in an expedited return to play.

Clinical Syndromic Phenotypes and the Potential Role of Genetics in Pulmonary Vein Stenosis.

Pulmonary vein stenosis (PVS) is a rare, frequently lethal disease with heterogeneous phenotypes and an unclear etiology. Limited studies have reported associations between PVS and congenital heart disease (CHD), chronic lung disease (CLD), and/or prematurity; however, to date, there have been no studies that report detailed clinical syndromic phenotypes and the potential role of genetics in PVS. An existing registry of multivessel PVS patients seen at Boston Children's Hospital (BCH) was queried between August 2006 and January 2017 for all existing genetic testing data on these patients. PVS was defined as an intraluminal pulmonary venous obstruction in ≥2 vessels with mean pressure gradients > 4 mmHg. One-hundred-and-fifty-seven patients (46% female, with a median age at PVS diagnosis of 3 months) formed the cohort. Seventy-one (45%) patients had available genetic testing information. Of the 71 patients, a likely genetic diagnosis was found in 23 (32%) patients: 13 (57%) were diagnosed with Trisomy 21 (T21), five (22%) with Smith-Lemli-Opitz Syndrome, five (22%) had other pathologic genetic disease, and 24 (33%) had variants of unknown significance. The majority of 13 patients with T21 and PVS had common atrioventricular canal (CAVC) (10, 77%) and all had severe pulmonary hypertension (PHTN), which led to their PVS diagnosis. In our study, PVS was associated with T21, the majority of whom also had CAVC and PHTN. Therefore, complete assessment of the pulmonary veins should be considered for all T21 patients, especially those with CAVC presenting with PHTN. Furthermore, prospective standardized genetic testing with detailed clinical phenotyping may prove informative about potential genetic etiologies of PVS.

Echocardiographic assessment of the tricuspid and pulmonary valves: a practical guideline from the British Society of Echocardiography.

Transthoracic echocardiography is the first-line imaging modality in the assessment of right-sided valve disease. The principle objectives of the echocardiographic study are to determine the aetiology, mechanism and severity of valvular dysfunction, as well as consequences on right heart remodelling and estimations of pulmonary artery pressure. Echocardiographic data must be integrated with symptoms, to inform optimal timing and technique of interventions. The most common tricuspid valve abnormality is regurgitation secondary to annular dilatation in the context of atrial fibrillation or left-sided heart disease. Significant pulmonary valve disease is most commonly seen in congenital heart abnormalities. The aetiology and mechanism of tricuspid and pulmonary valve disease can usually be identified by 2D assessment of leaflet morphology and motion. Colour flow and spectral Doppler are required for assessment of severity, which must integrate data from multiple imaging planes and modalities. Transoesophageal echo is used when transthoracic data is incomplete, although the anterior position of the right heart means that transthoracic imaging is often superior. Three-dimensional echocardiography is a pivotal tool for accurate quantification of right ventricular volumes and regurgitant lesion severity, anatomical characterisation of valve morphology and remodelling pattern, and procedural guidance for catheter-based interventions. Exercise echocardiography may be used to elucidate symptom status and demonstrate functional reserve. Cardiac magnetic resonance and CT should be considered for complimentary data including right ventricular volume quantification, and precise cardiac and extracardiac anatomy. This British Society of Echocardiography guideline aims to give practical advice on the standardised acquisition and interpretation of echocardiographic data relating to the pulmonary and tricuspid valves.

Efficacy and safety of chemical thromboprophylaxis in renal transplantation - A systematic review.

INTRODUCTION: The benefit of administering chemical thromboprophylaxis to chronic kidney disease patients undergoing renal transplantation is unclear and no previous systematic review has addressed this as reflected by variations in national guidelines. METHODS: A literature search was performed using MEDLINE, Embase, Cochrane, CINAHL, World Health Organisation (WHO) International Clinical Trials Registry Platform and ClinicalTrials.gov databases to December 2019. Studies included participants undergoing renal transplantation only with no contra-indication to thromboprophylaxis, no history/clinical suspicion of acute organ rejection and those describing a form of chemical thromboprophylaxis intervention compared with another form, no intervention or placebo. RESULTS: Thirteen studies with 1600 patients were included. There was wide variation concerning type of thromboprophylaxis, time of onset, dosing and duration. Reports of symptomatic/asymptomatic venous thromboembolism and mortality were limited. Seven studies reported on renal allograft thrombosis. When comparing thromboprophylaxis to no intervention, there was no evidence of difference for thrombosis risk (risk ratio 0.2; [95% CI 0.01-4.63]), however all studies were underpowered to answer this question. Six studies reported on major bleeding but type of intervention, timing of onset and duration of thromboprophylaxis varied significantly, making it difficult to pool data for further analysis. CONCLUSION: There is insufficient evidence to advise on efficacy and safety of chemical thromboprophylaxis in patients undergoing renal transplantation or to determine whether one chemical thromboprophylaxis is better than another thromboprophylaxis.

Echocardiographic assessment of the right heart in adults: a practical guideline from the British Society of Echocardiography

The structure and function of the right side of the heart is influenced by a wide range of physiological and pathological conditions. Quantification of right heart parameters is important in a variety of clinical scenarios including diagnosis, prognostication, and monitoring response to therapy. Although echocardiography remains the first-line imaging investigation for right heart assessment, published guidance is relatively sparse in comparison to that for the left ventricle. This guideline document from the British Society of Echocardiography describes the principles and practical aspects of right heart assessment by echocardiography, including quantification of chamber dimensions and function, as well as assessment of valvular function. While cut-off values for normality are included, a disease-oriented approach is advocated due to the considerable heterogeneity of structural and functional changes seen across the spectrum of diseases affecting the right heart. The complex anatomy of the right ventricle requires special considerations and echocardiographic techniques, which are set out in this document. The clinical relevance of right ventricular diastolic function is introduced, with practical guidance for its assessment. Finally, the relatively novel techniques of three-dimensional right ventricular echocardiography and right ventricular speckle tracking imaging are described. Despite these techniques holding considerable promise, issues relating to reproducibility and inter-vendor variation have limited their clinical utility to date.

Early Use of Fibrinogen Replacement Therapy in Postpartum Hemorrhage-A Systematic Review.

Fibrinogen levels drop early in postpartum hemorrhage (PPH), and low fibrinogen levels predict outcomes. There is increasing interest in replacing fibrinogen early in severe PPH and this systematic review's aim was to assess if early fibrinogen replacement therapy improves outcomes in severe PPH. We searched the following databases from inception to June 2019: CDSR and CENTRAL (The Cochrane Library), MEDLINE, Embase, CINAHL, PubMed, Transfusion Evidence Library, LILACS, Web of Science Conference Proceedings Citation Index-Science, ClinicalTrials.gov and the WHO International Clinical Trials Registry Portal. We included randomized (RCT) and well-designed controlled observational studies where fibrinogen replacement therapy was given early (within 90 minutes of bleeding) compared with standard protocol in pregnant women > 24 weeks' gestation who developed PPH, defined as estimated blood loss ≥500 mL up to 24 hours post-delivery. Two independent reviewers extracted and reviewed the data on the primary outcome of allogeneic blood transfusion at 24 hours after intervention and secondary outcomes including all-cause mortality, rate of thrombosis, and the need for surgical and non-surgical interventions. We identified 5 eligible studies: 2 completed (total of 299 women) RCTs comparing fibrinogen concentrate with placebo, and 3 ongoing RCTs. There was no completed study assessing cryoprecipitate transfusion. There was variation of: timings of intervention administration; severity of PPH; fibrinogen doses and use of tranexamic acid. There was insufficient evidence that early administration of fibrinogen in PPH reduces the need for allogeneic blood transfusion at 24 hours (risk ratio 0.83 (95% CI 0.54-1.26), P = 0.38) (2 trials, 299 participants) or improves other outcomes. Both studies were underpowered to answer our outcomes. There is a lack of evidence that early fibrinogen replacement therapy improves outcomes in PPH. Future studies are needed to address this, underpinned by data on the optimal fibrinogen dose, protocol-driven approaches versus targeted therapy, and cost-effectiveness of cryoprecipitate versus fibrinogen concentrate therapy in PPH.

A Rare Case of Lead-Induced Cardiomyopathy.

A 39-year-old man, painter by profession, presented with symptoms of heart failure. His work up was unrevealing except for elevated blood lead levels (BLL). He was started on guideline-directed medical therapy and was referred to occupational therapy. No improvement in his ejection fraction was noted until his BLL decreased. (Level of Difficulty: Intermediate.).