A multi-center trial on efficacy and safety of the LifeTech CeraFlexTM ASD occluder for transcatheter closure in patients with secundum atrial septal defects.

Background: The last decades have brought remarkable improvements in treatment strategy and occluder modification of secundum atrial septal defect (ASD) closure. Approval, efficacy and safety of ASD closure devices have previously been demonstrated. This study investigated the clinical efficacy and safety of the LifeTech CeraFlexTM ASD occluder for interventional closure of secundum ASD with a 6-month follow-up (FU). Methods: Procedure specific data was collected on patients considered for ASD closure with the CeraFlexTM occluder between April 2016 and December 2019 in three German centers. Efficacy and safety were assessed after device closure, at discharge, and at 6-month FU. Results: The primary endpoint (successful ASD closure without severe complications) was reached by 102/103 patients (99%). Device embolization occurred in two patients (one early and one late embolization). After early snare-retrieval of an embolized device, this ASD was closed surgically and in the other patient with late device embolization the defect was closed with a larger CeraFlexTM occluder. The secondary endpoint (clincal efficacy after 6 months) was reached by 94/98 patients since new onset of arrhythmia occurred in four patients. Three patients had withdrawn their study-participation and one patient had moderate residual shunt, but not related to the occluder. Incomplete right bundle branch block (iRBBB) was seen in 31 patients. At last FU only 17 patients had remaining iRBBB documenting effective volume unloading of the right ventricle. Conclusions: Catheter interventional closure of secundum ASDs with the CeraFlexTM ASD occluder was feasible, safe and effective in this study.

Peak Oxygen Uptake on Cardiopulmonary Exercise Test Is a Predictor for Severe Arrhythmic Events during Three-Year Follow-Up in Patients with Complex Congenital Heart Disease.

Patients with congenital heart disease (CHD) are at increased risk for severe arrhythmia and sudden cardiac death (SCD). Although implantable cardioverter defibrillators (ICD) effectively prevent SCD, risk stratification for primary prophylaxis in patients with CHD remains challenging. Patients with complex CHD undergoing CPET were included in this single-center study. Univariable and backwards stepwise multivariable logistic regression models were used to identify variables associated with the endpoint of severe arrhythmic event during three years of follow-up. Cut-off values were established with receiver operating characteristic (ROC) curve analysis. Survival analysis was conducted via Kaplan-Meier plots. Severe Arrhythmia was documented in 97 of 1194 patients (8.1%/3 years). Independent risk factors for severe arrhythmia during follow-up were old age and a low peak oxygen uptake (V.O2peak) on multivariable analysis. Patients with more advanced age and with V.O2peak values of less than 24.9 mL/min/kg were at significantly increased risk for the occurrence of severe arrhythmias during follow-up. The combined analysis of both risk factors yielded an additional benefit for risk assessment. Age at CPET and V.O2peak predict the risk for severe arrhythmic events and should be considered for risk stratification of SCD in patients with complex CHD.

Reduced Parasympathetic Activity in Patients With Different Types of Congenital Heart Disease and Associations to Exercise Capacity.

PURPOSE: Current research indicates an imbalance in the autonomic nervous system (ANS) pathway activities in patients with congenital heart disease (CHD). The heart rate variability (HRV) is a measure to quantify activities of the parasympathetic and sympathetic branches. This study evaluated the parasympathetic activity by means of HRV in patients with CHD, regarding diagnostic subgroups and CHD severity, and the association to exercise capacity. METHODS: From July 2016 to August 2018, a total of 222 patients with different types of CHD (28.4 ± 10.1 yr; 44% female) received breathing-controlled HRV measurement in the supine position. Based on 130 adjacent heartbeats, the root mean square of successive differences (RMSSD), a parasympathetic activity surrogate was estimated and log-transformed. Additionally, all patients underwent a cardiopulmonary exercise test. For comparison, a control group (CG) of 57 (29.0 ± 7.1 yr; 61% female) healthy volunteers was recruited. RESULTS: Patients with CHD exhibited reduced parasympathetic activity in comparison to the CG (lnRMSSD CHD: 3.55 ± 0.57 ms vs CG: 3.93 ± 0.55 ms; P < .001), with the lowest parasympathetic activity in patients with Fontan circulation (3.07 ± 0.54 ms; P < .001). Complex CHD (3.40 ± 0.54 ms) had worse values compared with patients with simple (3.87 ± 0.55 ms; P < .001) and moderate severity (3.74 ± 0.54 ms; P < .001). Better parasympathetic activity in CHD patients was associated with increased exercise capacity (r = 0.322; P < .001). CONCLUSIONS: Impaired parasympathetic activity suggests limited function of the ANS in patients with CHD. Further studies should focus on the association of exercise capacity and ANS to possibly improve parasympathetic activity and functional outcomes.

Patients with Single-Ventricle Physiology over the Age of 40 Years.

BACKGROUND: Single-ventricle physiology (SVP) is associated with significant morbidity and mortality at a young age. However, survival prospects have improved and risk factors for a negative outcome are well described in younger cohorts. Data regarding older adults is scarce. METHODS: In this study, SVP patients under active follow-up at our center who were ≥40 years of age at any point between January 2005 and December 2018 were included. Demographic data, as well as medical/surgical history were retrieved from hospital records. The primary end-point was all-cause mortality. RESULTS: Altogether, 49 patients (19 female (38.8%), mean age 49.2 ± 6.4 years) were included. Median follow-up time was 4.9 years (interquartile range (IQR): 1.8-8.5). Of these patients, 40 (81.6%) had undergone at least one cardiac surgery. The most common extracardiac comorbidities were thyroid dysfunction (n = 27, 55.1%) and renal disease (n = 15, 30.6%). During follow-up, 10 patients (20.4%) died. On univariate analysis, renal disease and liver cirrhosis were predictors of all-cause mortality. On multivariate analysis, only renal disease (hazard ratio (HR): 12.5, 95% confidence interval (CI): 1.5-106.3, p = 0.021) remained as an independent predictor. CONCLUSIONS: SVP patients ≥40 years of age are burdened with significant morbidity and mortality. Renal disease is an independent predictor of all-cause mortality.

Inspiratory muscle training did not improve exercise capacity and lung function in adult patients with Fontan circulation: A randomized controlled trial.

BACKGROUNDS: Patients with Fontan circulation have no subpulmonary ventricle and a passive pulmonary perfusion. Considerable percentage of the pulmonary blood flow is driven by pressure shift due to respiration. Impairments in respiratory musculature strength are associated with a reduced exercise capacity. This study investigated the effect of a daily six months inspiratory muscle training (IMT) on exercise and lung capacity in adult Fontan patients. METHODS: After a lung function and cardiopulmonary exercise test (CPET), 42 Fontan patients (50% female; 30.5 ± 8.1 years) were randomized into either an intervention group (IG), or a control group (CG). The IG performed a telephone-supervised, daily IMT of three sets with 10-30 repetitions for six months. RESULTS: After six months of IMT, the IG did not improve in any exercise and lung capacity parameter compared to CG. VO2peak (ΔVO2peak: IG: 0.05 [-1.53; 1.33] ml/kg/min vs. CG: -0.50 [-1.20; 0.78] ml/kg/min; p = .784) and FVC (ΔFVC: IG: 0.07 [-0.16; 0.22] l vs. CG:-0.05 [-0.24; 0.18] l; p = .377) remained unchanged, while FEV1 trended to improve (ΔFEV1: IG: 0.05 [-0.07; 0.13] l vs. CG: -0.10 [-0.19; 0.03] l; p = .082). Only oxygen saturation at rest improved significantly (ΔSpO2: IG: 1.50 [-0.25; 3.00] % vs. CG: -0.50 [-1.75; 0.75] %; p = .017). CONCLUSIONS: A daily six months IMT did not improve exercise and lung capacity and lung volumes in Fontan patients.

Oxygen Availability in Respiratory Muscles During Exercise in Children Following Fontan Operation.

Introduction: As survival of previously considered as lethal congenital heart disease forms is the case in our days, issues regarding quality of life including sport and daily activities emerge. In patients with Fontan circulation, there is no pump to propel blood into the pulmonary arteries since the systemic veins are directly connected to the pulmonary arteries. The complex hemodynamics of Fontan circulation include atrial function, peripheral muscle pump, integrity of the atrioventricular valve, absence of restrictive, or obstructive pulmonary lung function. Therefore, thoracic mechanics are of particular importance within the complex hemodynamics of Fontan circulation. Methods: To understand the physiology of respiratory muscles, the aim of this study was to examine the matching of auxiliary respiratory muscle oxygen delivery and utilization during incremental exercise in young male Fontan patients (n = 22, age = 12.04 ± 2.51) and healthy Controls (n = 10, age = 14.90 ± 2.23). All subjects underwent a cardiopulmonary exercise test (CPET) to exhaustion whereas respiratory muscle oxygenation was measured non-invasively using a near-infrared spectrometer (NIRS). Results: CPET revealed significantly lower peak power output, oxygen uptake and breath activity in Fontan patients. The onset of respiratory muscle deoxygenation was significantly earlier. The matching of local muscle perfusion to oxygen demand was significantly worse in Fontans between 50 and 90% V . O 2 peak . Findings: The results indicate that (a) there is high strain on respiratory muscles during incremental cycling exercise and (b) auxiliary respiratory muscles are worse perfused in patients who underwent a Fontan procedure compared to healthy Controls. This might be indicative of a more general skeletal muscle strain and worse perfusion in Fontan patients rather than a localized-limited to thoracic muscles phenomenon.