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There are limited data about the risk of pulmonary artery (PA) dissection in adults with congenital heart disease (CHD), and the purpose of this study was to estimate the incidence of PA dissection in this population.Retrospective cohort study of adults with CHD that underwent cross-sectional imaging (2003-2020). PA aneurysm was defined as main or branch PA diameter 40 mm or 30 mm respectively, and severe PA aneurysm was defined as main or branch PA diameter 50 mm.Of 1, 673 patients (41 ± 10 years; male 58%), 493 (24%), 286 (19%), and 306 (20%) had aneurysms of the main, right, and left PA respectively, while 66 (4%) had severe PA aneurysm. During a median follow-up of 8.2 (interquartile range 3.7-10.3) years, there was one PA dissection in a patient with Eisenmenger syndrome, thus the incidence of PA dissection was 14 per 100,000 patient-years. Of 779 females, 163 had one or more pregnancies during follow-up, and 41 (25%) of these patients had known PA aneurysm at the time of conception. There was no PA dissection during pregnancy. Of the 163 patients, 91 (56%) had cross-sectional imaging before and after pregnancy, there was no significant difference in PA dimension before versus after pregnancy (main PA 35 ± 5 versus 36 ± 4 mm, p = 0.6; right PA 21 ± 3 versus 33 ± 4 mm, p = 0.1; and left PA 23 ± 4 versus 22 ± 4 mm, p = 0.4).The risk of PA dissection was extremely low even in patients with severe PA aneurysm, or in patients with PA aneurysm that became pregnant. Collectively, these data suggest a benign natural history for patients without severe pulmonary hypertension and encourage and a conservative approach in managing patients with PA aneurysm.

There are conflicting data about the association between obesity and clinical outcomes in adults with congenital heart disease (CHD), and the effects of weight gain or weight loss remain unclear. The purpose of this study was to determine whether a temporal change in body mass index (BMI) was associated with clinical outcomes independent of baseline BMI in adults with CHD.Retrospective cohort study of adults with CHD that had clinical assessments at baseline and 5 years afterwards. Weight gain and weight loss were defined as ≥5% change from baseline BMI. Atherosclerotic cardiovascular disease (ASCVD) risk profile (blood pressure [BP], low density lipoprotein cholesterol [LDL-C] and hemoglobin A1C [HBA1c]) and cardiovascular events (heart failure hospitalization, transplant, death) were ascertained.Of the 3407, 1804 (53%) had stable weight, 1291 (38%) had weight gain, and 312 (9%) had weight loss at follow-up assessment. The median change in BMI (∆ BMI) was +3% (1-5). The baseline BMI and ∆ BMI were associated with worsening ASCVD risk profile (higher BP, LDL-C and HBA1C), and an increase in cardiovascular events in patients with obesity at baseline.Collectively, the results provide evidence to support lifestyle interventions aimed at weight maintenance in patients with normal weight, and to promote weight loss in patients that are overweight or obese. Further studies are required to determine the optimal type of lifestyle interventions that will be most effective in this population.

Background: Inferior vena cava (IVC) size and collapsibility (IVC dynamics) are used for estimating right atrial pressure (RAP). However, the diagnostic performance of the American Society of Echocardiography IVC criteria for estimating RAP in patients with congenital heart disease are unknown. The purpose of this study was to assess the role of IVC dynamics for estimating RAP in adults with congenital heart disease. Methods: We conducted a retrospective study of adults with congenital heart disease that underwent cardiac catheterization and echocardiogram at Mayo Clinic (2003–2019). IVC diameter was measured at inspiration (IVC min ) and end-expiration (IVC max ), and IVC collapsibility index (IVC CI ) was calculated. Results: Based on 918 patients, we observed a good correlation between IVC max and invasive RAP ( r =0.56, P min and RAP ( r =0.58, P CI ( r =−0.72, P CI ( r =0.80, P CI max >2.1 cm, area under the curve difference 0.15, P CI P =0.008; combination of IVC max >2.1 cm; and IVC CI P =0.02). Estimated RAP >10 mm Hg based on IVC CI had comparable prognostic performance as invasive RAP but superior prognostic performance as the American Society of Echocardiography criteria. Conclusions: IVC CI CI was comparable to invasively measured RAP in its relation to prognosis. Further studies are required to determine whether the use of IVC CI in clinical decision-making will improve clinical outcomes in this population.

Postoperative atrial fibrillation (POAF) is one of the most common complications after cardiac surgery. POAF is associated with a longer hospital stay, higher healthcare resource utilization, and higher risk of morbidity and mortality. As a result, the American and European guidelines recommend the use of beta-blockers and amiodarone for the prevention of POAF, and in turn, avoid the complications associated with POAF.The purpose of this study was to determine the incidence, risk factors, and prognostic implications of new-onset POAF after cardiac surgery in adults with congenital heart disease (CHD).A retrospective study was conducted among adults with CHD who underwent cardiac surgery (2003-2019). POAF and late-onset atrial fibrillation (AF) were defined as AF occurring within and after 30 days postoperatively, respectively.Of 1,598 patients (mean age 39 ± 13 years, 51% men), 335 (21%) developed POAF. Risk factors associated with POAF were older age, hypertension, left atrial (LA) reservoir strain and right atrial (RA) dysfunction, and nonsystemic atrioventricular valve regurgitation. Of 1,291 patients (81%) with follow-up ≥12 months, the annual incidence of late-onset AF was 1.5% and was higher in patients with POAF compared with those without POAF (5.9% vs 0.4%; P 0.001). Risk factors associated with late-onset AF were POAF, older age, severe CHD, and LA and RA dysfunction. Of the 1,291 patients, 63 (5%) died during follow-up, and the risk factors associated with all-cause mortality were older age, severe CHD, hypertension, left ventricular systolic dysfunction, and LA and RA dysfunction. POAF was not associated with all-cause mortality.POAF was common in adults with CHD and was associated with late-onset AF but not all-cause mortality. Atrial dysfunction was independently associated with POAF, late-onset AF, and all-cause mortality. These risk factors can be used to identify patients at risk for POAF and provide a foundation for prospective studies assessing the efficacy of prophylactic therapies in this population.

High-level synthesis (HLS) is an increasingly popular method for generating hardware from a description written in a software language like C/C++. Traditionally, HLS tools have operated on sequential code, however in recent years there has been a drive to synthesise multi-threaded code. In this context, a major challenge facing HLS tools is how to automatically partition memory among parallel threads to fully exploit the bandwidth available on an FPGA device and minimise memory contention. Existing partitioning approaches require inefficient arbitration circuitry to serialise accesses to each bank because they make conservative assumptions about which threads might access which memory banks. In this article, we design a static analysis that can prove certain memory banks are only accessed by certain threads, and use this analysis to simplify or even remove the arbiters while preserving correctness. We show how this analysis can be implemented using the Microsoft Boogie verifier on top of satisfiability modulo theories (SMT) solver, and propose a tool named EASY using automatic formal verification. Our work supports arbitrary input code with any irregular memory access patterns and indirect array addressing forms. We implement our approach in LLVM and integrate it into the LegUp HLS tool. For a set of typical application benchmarks our results have shown that EASY can achieve 0.13×(avg. 0.43×) of area and 1.64×(avg. 1.28×) of performance compared to the baseline, with little additional compilation time relative to the long time in hardware synthesis.

Mechanical mitral valve replacement in infants and young children is associated with substantial morbidity and mortality. Lifelong anticoagulation is required, with all the accompanying challenges of maintaining levels in infants and children whose dietary input continually changes. Even with careful control of all aspects that can perturb the coagulation cascade, these patients have a substantial lifelong risk of thrombotic and hemorrhagic complications that can also affect the durability of the valve. Anticoagulation is usually achieved utilizing warfarin with the degree of anticoagulation measured via the international normalized ratio (INR). Unfortunately, in some cases, the INR can be falsely elevated and lead to inappropriate reassurance. We describe a 4-year-old patient with complex congenital heart disease palliated via a single ventricular pathway with a mechanical atrioventricular valve replacement. The patient experienced acute valvular thrombosis while receiving warfarin with INR at target levels. Chromogenic factor X (CFX) levels were discordant with INR measurements, suggesting a subtherapeutic level of anticoagulation despite maintaining the standard INR target. Therefore, CFX levels were used to interpret INR measurements and guide an individualized approach to anticoagulation. We propose a new role of CFX: to verify and guide warfarin anticoagulation in high-risk pediatric patients including those undergoing mechanical mitral valve replacement.

Background: There are limited data about the stage D heart failure (advanced HF) in adults with congenital heart disease. Our study objectives were (1) to determine the incidence of new-onset advanced HF in patients and the relationship between advanced HF and all-cause mortality and (2) to determine the relationship between therapies for advanced HF and all-cause mortality. Methods: Retrospective cohort study of adults with congenital heart disease at Mayo Clinic (2003–2019). We defined advanced HF using the European Society of Cardiology diagnostic criteria for advanced HF. Therapies received by the patients with advanced HF were classified into 3 mutually exclusive groups (treatment pathways): (1) conventional cardiac intervention, (2) transplant listing, and (3) palliative care. Results: Of 5309 patients without advanced HF at baseline assessment, 432 (8%) developed advanced HF during follow-up (1.1%/y), and the incidence of advanced HF was higher in patients with severe or complex congenital heart disease. Onset of advanced HF was associated with 6-fold increase in the risk of mortality. Conventional cardiac intervention was associated with significantly higher risk of mortality as compared to transplant listing. The longer the interval from the initial onset of advanced HF to transplant evaluation, the lower the odds of being listed for transplant. Conclusions: Based on these data, we postulate that early identification of patients with advanced HF, and a timely referral for transplant evaluation (instead of conventional cardiac intervention) may offer the best chance of survival for these critically ill patients. Further studies are required to validate this postulation.

Background: Left ventricular global longitudinal strain (LVGLS) has been shown to improve risk stratification in patients with LV systolic dysfunction and subsequent recovery of LV ejection fraction (LVEF) in the acquired heart disease population. The purpose of this study was to assess the relationship between LVGLS and cardiovascular events (heart failure hospitalization, sustained ventricular tachycardia/appropriate shock, heart transplant, or cardiovascular death) and deterioration in LVEF (absolute decrease in LVEF ≥10% to LVEF Methods: Retrospective cohort study of congenital heart disease patients with previous diagnosis of LV systolic dysfunction (LVEF 18%) versus abnormal LVGLS (absolute LVGLS ≤18%) groups. Results: Of 193 patients with recovered LVEF, 86 (45%) had normalization of LVGLS at index echocardiogram. A higher absolute LVGLS and use of renin angiotensin aldosterone system antagonist was associated with a lower risk of cardiovascular events and subsequent deterioration in LVEF, while hypertension was associated with higher risk of cardiovascular events and deterioration in LVEF. Conclusions: These results suggest that patients with congenital heart disease with recovered LVEF remained at risk for adverse outcomes, and LVGLS can be used to identify patients at risk for adverse outcomes. Medical therapy for heart failure and treatment of hypertension may reduce the risk of adverse outcome, but these findings require empirical validation, hence the need for a clinical trial.

Left atrial (LA) reservoir strain18% and booster strain8% have been proposed as the optimal threshold to detect increased left ventricular (LV) filling pressure in patients with acquired heart disease. The purpose of this study was to determine whether these LA strain cut-off points can detect increased LV filling pressure in adults with coarctation of aorta (COA).This retrospective study included adults with COA (n = 126; age, 36 ± 16 years) who underwent non-simultaneous cardiac catheterization and echocardiography. Increased LV filling pressure was defined as pulmonary artery wedge pressure (PAWP)12 mm Hg or LV end-diastolic pressure (LVEDP)16 mm Hg.The median PAWP was 13 mm Hg (interquartile range [IQR], 11-18) and PAWP had a good correlation with LA reservoir strain (r = -0.69; P.001) and LA booster strain (r = -0.61; P.001). LA reservoir strain18% had superior diagnostic power to detect PAWP12 mm Hg as compared with LA volume index34 mL/m², septal E/e'15, lateral E/e'13, and tricuspid regurgitation velocity2.8 m/s (P.05 for all). The median LVEDP was 17 mm Hg (IQR, 14-20) and LVEDP had a modest correlation with LA reservoir strain (r = -0.39; P.001) and LA booster strain (r = -0.33; P.01). LA reservoir strain18% had superior diagnostic power to detect LVEDP16 mm Hg as compared with LA volume index34 mL/m², septal E/e'15, lateral E/e'13, and tricuspid regurgitation velocity2.8 m/s (P.05 for all).These data suggest that LA strain could potentially be used to identify patients with increased LV filling pressure, thereby improving patient selection for cardiac catheterization and interventions.

A 44-year-old man with history of D-transposition of the great arteries status post Mustard repair with pulmonary baffle obstruction was referred for further management. Cardiac computed tomography demonstrated calcific stenosis of the pulmonary venous baffle (PVB) outflow and right heart catheterization demonstrated elevated superior vena cava, pulmonary artery, and pulmonary capillary wedge pressures. A course of treatment is described demonstrating the challenges and potential complications of hybrid PVB stenting in a patient with challenging anatomy.

Despite their universal predisposition, diagnosing diastolic dysfunction in patients post-Fontan palliation is challenging. Our aim was to compare exercise haemodynamics between adults post-Fontan and patients with heart failure with preserved ejection fraction (HFpEF) and non-cardiac dyspnoea (NCD).Twenty-four adults (age ≥18 years) post-Fontan palliation with resting and exercise pulmonary artery wedge pressure (PAWP) measured during supine biking were identified. Forty-eight patients with HFpEF and 48 with NCD diagnosed at catheterization were selected for comparison. Mean age for Fontan patients was 30.3 ± 7.5 years; median ventricular ejection fraction was 52.5% (45-55.8), being50% in 37.5%. Resting PAWP among Fontan patients was 10.2 ± 3.5 mmHg (12 mmHg in 25%); PAWP was lower in Fontan patients than in HFpEF but higher than NCD. During exercise, PAWP was lower in the Fontan group than HFpEF (22.5 mmHg [19.3-28] vs. 28.2 ± 6.3; p = 0.0006) but higher than NCD (11.2 ± 4.2, p ≤ 0.0001). However, there were no differences in ΔPAWP/ΔQs between Fontan and HFpEF patients (4.0 [2.1-7.3] vs. 2.7 [1.6-4.4]; p = 0.10) with the ratio being higher post-Fontan than in NCD (0.6 [0.2-1.2]; p 0.0001). ΔPAWP/ΔQs remained similar between HFpEF and Fontan patients even when those with ejection fraction50% were excluded (2.7 [1.6-4.4] vs. 2.7 [1.0-5.8]; p = 0.97).There were no differences in ΔPAWP/ΔQs ratios between post-Fontan and HFpEF patients, supporting markedly abnormal single ventricle compliance despite lower resting and exercise PAWP. Therefore, exercise invasive haemodynamics may represent a novel tool for the diagnosis of diastolic dysfunction in Fontan patients.

Background Right-sided heart failure remains a challenge in the care of congenital heart disease patients, both those with right ventricular dilation and dysfunction and those with right ventricular hypoplasia. Two strategies for treatment are atrial septal fenestration and bidirectional cavopulmonary shunt (BCPS). Methods This review details the strategies for right ventricular unloading, with summaries of pertinent data and commentaries on the subject. Results While atrial septal fenestration provides right ventricular unloading and can be appropriate in cases of moderate right ventricular dysfunction and dilation, this unloading is not as substantial as a BCPS. A BCPS more effectively unloads the right ventricle, provides preload to the left ventricle, and can significantly improve ventricular-ventricular interactions. A BCPS is often appropriate in cases of severe right ventricular dysfunction and dilation, if factors favorable for BCPS circulation are in place. Certain anatomic and physiologic factors assessed both preoperatively and intraoperatively help guide the decision regarding which patient may benefit from right ventricular unloading and which technique is optimal. Conclusions When used strategically in select patients, BCPS and atrial-level fenestration are effective in managing right ventricular failure in congenital heart disease patients. Preoperative imaging and intraoperative anatomic and physiologic factors help guide the appropriate management for a given patient.

There are limited data on the prognostic role of hepatorenal function indices in ambulatory patients with congenital heart disease (CHD). The purpose of this study was to determine the prevalence, risk factors, and prognostic implications of hepatorenal dysfunction, as measured by Model for End-Stage Liver Disease Excluding International Normalised Ratio (MELD-XI) score, in adults with CHD.In this retrospective study of CHD patients with comprehensive metabolic panels (2003-2019), mild/moderate and severe hepatorenal dysfunction was defined as MELD-XI 11-15 and15, respectively.Of 4977 patients, 1376 (28%) had hepatorenal dysfunction (mild/moderate: n = 935 [19%]; severe: n = 441 [9%]). Hepatorenal dysfunction was most common in Fontan/unrepaired single ventricle (46%) and right heart disease (31%). Baseline MELD-XI was associated with all-cause mortality (HR 1.27, CI 1.21-1.33; P0.001) after adjustment for age, sex, and congenital heart lesion. In 3864 patients with serial MELD-XI data, there was a temporal increase in MELD-XI, and this was associated with an increased risk of mortality (HR 1.24, CI 1.15-1.36, per unit increase in MELD-XI; P = 0.004), independently from the baseline MELD-XI score. In the subset of 1856 patients that underwent surgical/transcatheter interventions, there was a postoperative reduction in MELD-XI, and this was associated with a lower risk of mortality (HR 0.94, CI 0.90-0.98, per unit decrease in MELD-XI; P = 0.008), independently from the baseline MELD-XI score.Hepatorenal dysfunction was common in adults with CHD. Both baseline MELD-XI score and temporal changes in MELD-XI were associated with clinical outcomes, and therefore could be used to monitor therapeutic response to interventions and for deterioration in clinical status.

Pulmonary vascular disease, pulmonary endothelial dysfunction, liver fibrosis, renal disease, and exercise intolerance are common in adults with Fontan physiology. Although the pathophysiologic mechanisms linking these phenomena have been studied, certain aspects are not well understood.This study hypothesized that impaired pulmonary vascular reserve (VR) plays a central role linking these abnormalities, and that patients with abnormal pulmonary VR with exercise, compared with patients with normal VR, would display poorer pulmonary endothelial function, greater liver stiffness, more renal dysfunction, and poorer exercise capacity.Symptomatic adults with the Fontan palliation (n = 29) underwent invasive cardiopulmonary exercise testing, echocardiography, and assessment of microvascular function. Abnormal pulmonary VR was defined by the slope of increase in pulmonary pressure relative to cardiac output with exercise3 mm Hg/l/min. Pulmonary endothelial function was assessed using reactive hyperemia index. End-organ function was assessed using magnetic resonance elastography-derived liver stiffness, glomerular filtration rate, N-terminal pro-B-type natriuretic peptide, and peak oxygen consumption (VoCompared with individuals with normal VR (n = 8), those with abnormal VR (n = 21) displayed higher central and pulmonary venous pressures, and more severely impaired cardiac output and stroke volume responses to exertion, but similar pulmonary vascular resistance at rest. Patients with abnormal VR displayed more severely impaired reactive hyperemia index, increased liver stiffness, lower glomerular filtration rate, higher N-terminal pro-B-type natriuretic peptide, and lower peak VoPulmonary vascular limitations in Fontan physiology are related to pulmonary endothelial and end-organ dysfunction, suggesting a mechanistic link between these commonly observed findings, and these abnormalities are more apparent during exercise testing, with little relationship at rest.

BACKGROUND: Transcatheter stent therapy is as effective as surgery in producing acute hemodynamic improvement in patients with coarctation of aorta (COA). However, left ventricular (LV) remodeling after transcatheter COA intervention has not been systematically investigated. The purpose of this retrospective cohort study was to compare remodeling of LV structure and function after transcatheter stent therapy vs surgical therapy for COA. METHODS: LV remodeling was assessed at 1, 3 and 5-years post-intervention using: LV mass index (LVMI), LV end-diastolic dimension, LV ejection fraction, LV global longitudinal strain (LVGLS), LV e’ and E/e’. RESULTS: There were 44 and 128 patients in the transcatheter and surgical groups respectively. Compared to the surgical group, the transcatheter group had less regression of LVMI (−4.6[95%CI −5.5 - −3.7] vs −7.3[95%CI −8.4 - −6.6] g/m(2), p

Hardened adder and carry logic is widely used in commercial field-programmable gate arrays (FPGAs) to improve the efficiency of arithmetic functions. There are many design choices and complexities associated with such hardening, including circuit design, FPGA architectural choices, and the computer-aided design (CAD) flow. However, these choices have not been studied much and hence we explore a number of possibilities. We also highlight front-end elaboration optimization that helps ameliorate the restrictions placed on logic synthesis by hardened arithmetic. We show that hard adders and carry chains increase the performance of simple adders by a factor of 4 or more, but on larger benchmark designs that contain arithmetic improve the overall performance by 15%. Our results also show that for complete application circuits simple hardened ripple-carry adders perform as well as more complex carry-lookahead adders. Our best non-fracturable lookup table (non-fLUT) architecture with hardened arithmetic yields 12% better area–delay product than architectures without hardened arithmetic. We also investigate the impact of fLUTs and their interaction with hardened arithmetic. We find that fLUTs offer significant (12%–15%) area reduction, which is complementary to the delay reduction of hardened arithmetic. Therefore, our best fLUT architectures which use two bits of hardened arithmetic achieve 25% better area–delay product than non-fLUT architectures without hardened arithmetic.

Background: Inferior vena cava (IVC) size and collapsibility provide a noninvasive estimate of right heart filling pressures, an important determinant of right heart hemodynamic performance that is not measured by cardiac magnetic resonance imaging (CMRI). We hypothesized that compared with CMRI risk model alone, a combined CMRI-IVC risk model will have better correlation with disease severity and peak oxygen consumption in patients with tetralogy of Fallot (TOF). Methods: We performed a retrospective review of patients with TOF with moderate/severe pulmonary regurgitation who underwent CMRI and echocardiography. A CMRI risk model was constructed using right ventricular (RV) end-diastolic volume index, RV end-systolic volume index, RV ejection fraction, and left ventricular ejection fraction. We added IVC hemodynamic classification to the CMRI indices to create CMRI-IVC risk model, and IVC hemodynamics were modeled as a categorical variable: normal vs mild/moderately abnormal (dilated IVC or reduced collapsibility) vs severely abnormal IVC hemodynamics (dilated IVC and reduced collapsibility). We defined disease severity as atrial arrhythmias, ventricular arrhythmias, and heart failure hospitalization. Results: Of 207 patients, 131 (63%), 72 (35%), and 4 (2%) had normal, mild/moderately abnormal, and severely abnormal IVC hemodynamics, respectively. Compared with the CMRI risk model, the CMRI-IVC risk model had a better correlation with disease severity (area under the curve, 0.62; 95% confidence interval, 0.51-0.74 vs area under the curve 0.84, 95% confidence interval, 0.78-0.91, P = 0.006) and peak oxygen consumption (r = 0.35, P = 0.042 vs r = 0.43, P = 0.031, Meng test P = 0.026). Conclusions: The combined CMRI-IVC risk model had a better correlation with disease severity compared with CMRI indices alone and can potentially improve risk stratification in the population with TOF. Résumé: Contexte: Le diamètre et la collapsibilité de la veine cave inférieure (VCI) permettent d’estimer de façon non invasive les pressions de remplissage du cœur droit, un déterminant important de la capacité hémodynamique cardiaque droite que ne mesure pas l’imagerie par résonance magnétique cardiaque (IRMC). Notre hypothèse était que, comparativement au modèle de risque IRMC seul, un modèle de risque combiné IRMC-VCI présenterait une meilleure corrélation avec la gravité de la maladie et la consommation maximale d’oxygène chez les patients atteints de la tétralogie de Fallot (TF). Méthodologie: Nous avons effectué une étude rétrospective de cas de TF avec régurgitation pulmonaire modérée ou sévère où les patients ont subi un examen d’IRMC et une échocardiographie. Nous avons créé un modèle de risque IRMC intégrant l’indice du volume télédiastolique ventriculaire droit, l’indice du volume télésystolique ventriculaire droit, la fraction d’éjection ventriculaire droite et la fraction d’éjection ventriculaire gauche. Nous avons ajouté une classification hémodynamique de la VCI aux indices d’IRMC pour créer le modèle de risque IRMC-VCI, et les caractéristiques hémodynamiques de la VCI ont été modélisées en tant que variable nominale : état normal vs anomalie légère ou modérée (VCI dilatée ou collapsibilité réduite) vs anomalie sévère des caractéristiques hémodynamiques de la VCI (VCI dilatée et collapsibilité réduite). Nous avons défini la gravité de la maladie en distinguant les arythmies auriculaires, les arythmies ventriculaires et l’insuffisance cardiaque entraînant une hospitalisation. Résultats: Au sein d’un groupe de 207 patients, les caractéristiques hémodynamiques de la VCI présentaient un état normal, une anomalie légère ou modérée et une anomalie sévère dans 131 cas (63 %), 72 cas (35 %) et 4 cas (2 %), respectivement. Comparativement au modèle de risque IRMC, le modèle de risque IRMC-VCI a présenté une meilleure corrélation avec la gravité de la maladie (aire sous la courbe = 0,62 et intervalle de confiance à 95 % = 0,51-0,74 vs aire sous la courbe = 0,84 et intervalle de confiance à 95 % = 0,78-0,91, p = 0,006) et avec la consommation maximale d’oxygène (r = 0,35, p = 0,042 vs r = 0,43, p = 0,031, p = 0,026 pour le test de Meng). Conclusions: Le modèle de risque combiné IRMC-VCI a présenté une meilleure corrélation avec la gravité de la maladie comparativement aux indices d’IRMC seuls. Il pourrait améliorer la stratification du risque au sein de la population atteinte de la TF.

The clinical implications of finding immobile leaflet(s) at the time of bioprosthetic valve implantation but with acceptable prosthetic haemodynamics are uncertain. We sought to determine the characteristics of such patients and their impact on outcome.Patients with immobile leaflet at the time of surgical bioprosthetic valve implantation were identified retrospectively by a systematic search of an institutional echocardiography database (2010-2020). Intraoperative echocardiograms were reviewed de-novo to confirm immobile leaflet(s) at the time of implantation. Cases were matched 1:2 to controls with normal bioprosthetic leaflets motion for age, sex, prosthesis position, prosthesis model, size, year of implantation, and pre-implantation left ventricular ejection fraction. Proportional hazards method was used to analyse the composite endpoint of stroke, valve thrombosis or re-intervention.Immobile leaflet at the time of bioprosthetic valve implantation were found in 26 patients (median age 71 ys 39% males) following tricuspid (n=13), mitral (n=11) and aortic (n=2) valve replacements; 96% received porcine prostheses; prosthesis size was 27 mm or larger in 92%. Immobile leaflet were recorded on intraoperative reports in 16 (62%) cases. It resulted in elevated gradient or mild-moderate prosthetic regurgitation in three (12%), but none led to immediate corrective action intraoperatively. At median follow-up of 21 (4-50) months, presence of immobile leaflet was associated with composite clinical endpoint of stroke, valve thrombosis or re-intervention (hazard ratio 6.8, 95% CI 1.8-25.2, p0.01) compared to controls.Immobile leaflet immediately post-bioprosthetic valve implantation is frequently under-recognised intraoperatively and appears to be associated with early bioprosthetic dysfunction and worse clinical outcome.

We describe a framework for automated generation of hybrid processor/accelerator systems comprising a RISC-V processor, and a coarse-grained reconfigurable array (CGRA) for realizing compute-kernel acceleration. CGRAs are programmable hardware platforms having an array of coarse ALU-like processing elements, and word-wide programmable interconnect. The proposed framework integrates CGRAs generated by the open-source CGRA-ME tool [1], with the RISC-V processor from the PULP project [2]. In an experimental study, we use the framework to generate RISC-V+CGRA systems that provide an order-of-magnitude speedup vs. software and considerable speedup vs. a vector processor on several applications by leveraging the CGRA spatial and pipeline parallelism. As CGRA-ME permits a variety of different CGRAs to be modelled and mapped to, we believe the proposed framework represents a powerful open-source platform, enabling a variety of new research on processor/CGRA system architectures and programming models.

The purpose of this study was to describe procedural outcomes, hemodynamic improvement, regression of left ventricular (LV) mass hypertrophy, and cardiovascular. The primary outcomes were procedural complications, reinterventions, and hemodynamic improvement after coarctation of aorta (COA) repair. The secondary outcomes were improvement in the severity of hypertension, regression of LV mass index, and incidence of cardiovascular events (atrial fibrillation, ventricular tachycardia, heart failure hospitalization, and cardiovascular death) after COA repair. Secondary outcomes were assessed only in patients with isolated COA who had clinical and imaging follow-up at 1 year and 3 years postintervention. Of 172 patients that underwent COA repair (surgical 161; transcatheter 11), there were no procedural deaths, and all patients had residual COA gradient P =0.4 at baseline, 1 year and 3 years). Postintervention hypertension (both stage 1 and 2) were independent risk factors for suboptimal left ventricular mass index regression and cardiovascular events. Persistent hypertension was common after repair of native COA in adults and was associated with suboptimal left ventricular mass index regression and cardiovascular events. These results suggest that optimal blood pressure control with medical therapy after COA repair may result in improved clinical outcomes.

Coarse-grained reconfigurable arrays (CGRAs) are programmable hardware platforms that can be used to realize application-specific accelerators for higher performance and energy efficiency. A CGRA is a 2D array of configurable logic blocks & interconnect, where the logic blocks are typically large & ALU-like, and the interconnect is word-wide. CGRA-ME is a software framework that enables the modelling and exploration of CGRA architectures, as well as research on CGRA CAD algorithms. With CGRA-ME, an architect can specify a CGRA architecture at a high level of abstraction. A set of applications can be mapped onto the architecture to assess the mappability, power, performance and cost. CGRA-ME also allows one to generate synthesizable Verilog RTL for the modelled CGRA, permitting its implementation as an ASIC or FPGA overlay. In this paper, we describe the CGRA-ME framework [5] and overview its capabilities and current limitations. We discuss ongoing and prior research conducted with the framework, as well as outline future plans. We believe CGRA-ME will be a valuable contribution to the community, enabling new research on CGRA CAD & architectures.

We consider double-pumped interconnect as a means of area reduction in coarse-grained reconfigurable arrays (CGRAs). Interconnect multiplexers comprise a considerable portion of CGRA area. We apply double-pumping to halve the word-width of the interconnect multiplexers, saving area. The interconnect is operated at twice the system clock frequency, where the top and bottom half-words of a value are communicated in the first and second half of a clock cycle. Several circuit-level approaches for double-pumping are considered, and evaluated in different CGRA architectures with varied interconnect richness. Area and performance consequences are assessed through a 45nm standard-cell ASIC implementation. Overall CGRA area improvements of up to 16% are observed, depending on the CGRA architecture and double-pumping implementation.

A feature associated with coarse-grained reconfigurable arrays (CGRAs) is dynamic reconfigurability, wherein the CGRA supports multiple contexts. The multiple contexts form a set of configuration bitstreams that are loaded into the CGRA simultaneously and cycled through according to a schedule. Multi-context allows the CGRA hardware to be time-multiplexed: the logic blocks and interconnect can perform different functions according to the context selected in a given clock cycle. We consider how multi-context may be implemented at the circuit level, and evaluate three circuit implementations from the power, performance and area (PPA) perspectives. Results show that the choice of multi-context circuit implementation has an appreciable impact on the overall CGRA PPA. We also quantify the PPA overhead of the multi-context feature in CGRAs vs. a single-context device.

Objective: To identify risk factors for pediatric mechanical mitral valve replacement (mMVR) to improve management in this challenging population. Methods: From 1993 to 2019, 93 children underwent 119 mMVR operations (median age, 8.8 years [interquartile range [IQR]: 2.1-13.3], 54.6% females) at our institution. Twenty-six (21.8%) patients underwent mMVR at ≤2 years and 93 (78.2%) patients underwent mMVR at >2 years. Median follow-up duration was 7.6 years [IQR: 3.2-12.4]. Results: Early mortality was 9.7%, but decreased with time and was 0% in the most recent era (13.9% from 1993 to 2000, 7.3% from 2001 to 2010, 0% from 2011 to 2019, P = .04). It was higher in patients ≤2 years compared to patients >2 years (26.9% vs 2.2%, P < .01). On multivariable analysis for mitral valve reoperation, valve size 2 years and those with a prosthesis ≥23 mm. Median time to reoperation was 7 years (IQR: 4.5-9.1) in patients >2 years and 3.5 years (IQR: 0.6-7.1) in patients ≤2 years ( P = .0511), but was similar between prosthesis sizes ( P = .6). During follow-up period (median 7.6 years [IQR: 3.2-12.4], stroke occurred in 10%, prosthetic valve thrombosis requiring reoperation in 4%, endocarditis in 3%, and bleeding in 1%. Conclusion: Early and late outcomes of mMVR in children are improved when performed at age >2 years and with prosthesis size ≥23 mm. These factors should be considered in the timing of mMVR.

Transcatheter stent therapy provides similar acute reduction in coarctation of aorta (COA) gradient and systolic blood pressure (SBP) as compared with surgery. However, there are limited data comparing mid-term outcomes after transcatheter vs surgical therapy for COA. The purpose of this study was to compare temporal changes in Doppler COA gradient and SBP after transcatheter stent therapy versus surgical therapy for COA.A retrospective study of COA patients (≥18 years old) undergoing transcatheter stent therapy or surgical therapy at Mayo Clinic in Rochester, Minnesota from 2000-2018 was performed. Linear regression analyses were used to compare temporal changes in Doppler gradient and SBP between the 2 groups. Propensity matching was used to adjust for between-group differences in clinical and anatomic characteristics.A total of 44 and 128 patients underwent transcatheter and surgical therapy, respectively; there were no significant between-group differences in the anatomy of the thoracic aorta. Both groups had similar acute reduction in Doppler peak gradient (P=.66), mean gradient (P=.41), SBP (P=.22), and upper-to-lower extremity SBP (ULE-SBP) gradient (P=.69). The median follow-up was 46 months (interquartile range, 27-81 months) and 63 months (interquartile range, 41-94 months) in the transcatheter and surgical groups, respectively. There were no significant between-group differences in the temporal change in Doppler peak gradient (P-interaction=.06), mean gradient (P-interaction=.15), SBP (P-interaction=.20), and ULE-SBP gradient (P-interaction=.51).These favorable short- and mid-term outcome data support the use of transcatheter therapy as an alternative to surgery in adults with COA. Further studies are required to determine if these favorable outcomes are maintained on long-term follow-up.

The rising popularity of high-level synthesis (HLS) is due to the complexity and amount of background knowledge required to design hardware circuits. Despite significant recent advances in HLS research, HLS-generated circuits may be of lower quality than human-expert-designed circuits, from the performance, power, or area perspectives. In this work, we aim to raise circuit performance by introducing a transactional memory (TM) synchronization model to the open-source LegUp HLS tool [1]. LegUp HLS supports the synthesis of multi-threaded software into parallel hardware [4], including support for mutual-exclusion lock-based synchronization. With the introduction of transactional memory-based synchronization, location-specific (i.e. finer grained) memory locks are made possible, where instead of placing an access lock around an entire array, one can place a lock around individual array elements. Significant circuit performance improvements are observed through reduced stalls due to contention, and greater memory-access parallelism. On a set of 5 parallel benchmarks, wall-clock time is improved by 2.0×, on average, by the TM synchronization model vs. mutex-based locks.

Stochastic computing (SC), with its probabilistic data representation format, has sparked renewed interest due to its ability to use very simple circuits to implement complex operations. Though unlike traditional binary computing, SC needs to carefully handle correlations that exist across data values to avoid the risk of unacceptably inaccurate results. With many SC circuits designed to operate under the assumption that input values are independent, it is important to provide the ability to accurately measure and characterize independence of SC bitstreams. We propose zero correlation error (ZCE), a metric that quantifies how independent two finite-length bitstreams are, and show that it addresses fundamental limitations in metrics currently used by the SC community. Through evaluation at both the functional unit level and application level, we demonstrate how ZCE can be an effective tool for analyzing SC bitstreams, simulating circuits and design space exploration.

Endocarditis has emerged as one of the most impactful adverse events after transcatheter pulmonary valve replacement (TPVR), but there is limited information about risk factors for and outcomes of this complication.The purpose of this study was to evaluate risk factors for and outcomes of endocarditis in a large multicenter cohort.The authors established an international registry focused on characterizing endocarditis after TPVR, including the incidence, risk factors, characteristics, and outcomes.Investigators submitted data for 2,476 patients who underwent TPVR between July 2005 and March 2020 and were followed for 8,475 patient-years. In total, 182 patients were diagnosed with endocarditis a median of 2.7 years after TPVR, for a cumulative incidence of 9.5% (95% CI: 7.9%-11.1%) at 5 years and 16.9% (95% CI: 14.2%-19.8%) at 8 years (accounting for competing risks: death, heart transplant, and explant) and an annualized incidence of 2.2 per 100 patient-years. Staphylococcus aureus and Viridans group Streptococcus species together accounted for 56% of cases. Multivariable analysis confirmed that younger age, a previous history of endocarditis, and a higher residual gradient were risk factors for endocarditis, but transcatheter pulmonary valve type was not. Overall, right ventricular outflow tract (RVOT) reintervention was less often to treat endocarditis than for other reasons, but valve explant was more often caused by endocarditis. Endocarditis was severe in 44% of patients, and 12 patients (6.6%) died, nearly all of whom were infected with Staphylococcus aureus.The incidence of endocarditis in this multicenter registry was constant over time and consistent with prior smaller studies. The findings of this study, along with ongoing efforts to understand and mitigate risk, will be critical to improve the lifetime management of patients with heart disease involving the RVOT. Although endocarditis can be a serious adverse outcome, TPVR remains an important tool in the management of RVOT dysfunction.

Funding Acknowledgements Type of funding sources: None. BACKGROUND Detection of immobile leaflets immediately following bioprosthetic valve implantation is a rare but important intraoperative finding. Restriction of leaflet movement can occur in the closed or open position, leading to abnormal prosthesis function. We sought to determine the clinical implications of immobile leaflets seen on intraoperative echocardiography. METHODS Patients with immobile leaflets identified on intra-operative/procedure echocardiography immediately post implantation between 2009-2020 were identified from an institutional database. All echocardiograms were reviewed de-novo to confirm immobile leaflets in the immediate post-implantation period. Identified cases were matched 1:2 to controls for age; sex; prosthesis position, model and size; and implantation approach (surgical vs. transcatheter). Nominal logistic regression and proportional hazards were used to analyze outcomes. RESULTS Thirty patients with immobile leaflets immediately post-bioprosthesis implantation were included. Clinical characteristics are summarized in the Table. Immobile leaflets were documented in procedural reports in only 18 (60%) patients. Moderate stenosis was present intraoperatively in 1 patient, none demonstrated ≥moderate regurgitation, and none resulted in immediate corrective action. In 3 (10%), valve re-intervention was required within 30 days due to symptomatic prosthesis dysfunction. Presence of restricted leaflet motion was associated with higher need for post-operative extracorporeal membrane oxygenation use (odds-ratio 7.3, p = 0.02) and composite end-point of death, valve re-replacement, prosthesis thrombosis, or cardiac hospitalizations (risk ratio 2.1, p = 0.03, Figure). CONCLUSION Immobile leaflet(s) immediately post-bioprosthetic valve implantation is an uncommon, under-reported, and under-treated phenomenon. Even in the absence of significant prosthetic valve dysfunction, it can be associated with worse post-operative course as well as worse outcomes. Baseline characteristics Age 76 (67-84) Sex, male 10 (33%) Surgical approach 25 (83%) Aortic 5 (17%) Mitral 12 (40%) Tricuspid 12 (40%) Pulmonary 1 (3%) Re-intervention within 10 days 3 (10%) Numbers are presented as median (interquartile range) or number (percentage). Abstract Figure. Clinical outcome of stuck leaflets