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Image-based patient-specific modelling of hemodynamics are gaining increased popularity as a diagnosis and outcome prediction solution for a variety of cardiovascular diseases. While their potential to improve diagnostic capabilities and thereby clinical outcome is widely recognized, these methods require considerable computational resources since they are mostly based on conventional numerical methods such as computational fluid dynamics (CFD). As an alternative to the numerical methods, we propose a machine learning (ML) based approach to calculate patient-specific hemodynamic parameters. Compared to CFD based methods, our approach holds the benefit of being able to calculate a patient-specific hemodynamic outcome instantly with little need for computational power. In this proof-of-concept study, we present a deep artificial neural network (ANN) capable of computing hemodynamics for patients with aortic coarctation in a centerline aggregated (i.e., locally averaged) form. Considering the complex relation between vessels shape and hemodynamics on the one hand and the limited availability of suitable clinical data on the other, a sufficient accuracy of the ANN may however not be achieved with available data only. Another key aspect of this study is therefore the successful augmentation of available clinical data. Using a statistical shape model, additional training data was generated which substantially increased the ANN's accuracy, showcasing the ability of ML based methods to perform in-silico modelling tasks previously requiring resource intensive CFD simulations.

Supplemental Digital Content is available in the text., Background: Many heart diseases can result in reduced pumping capacity of the heart muscle. A mismatch between ATP demand and ATP production of cardiomyocytes is one of the possible causes. Assessment of the relation between myocardial ATP production (MVATP) and cardiac workload is important for better understanding disease development and choice of nutritional or pharmacologic treatment strategies. Because there is no method for measuring MVATP in vivo, the use of physiology-based metabolic models in conjunction with protein abundance data is an attractive approach. METHOD: We developed a comprehensive kinetic model of cardiac energy metabolism (CARDIOKIN1) that recapitulates numerous experimental findings on cardiac metabolism obtained with isolated cardiomyocytes, perfused animal hearts, and in vivo studies with humans. We used the model to assess the energy status of the left ventricle of healthy participants and patients with aortic stenosis and mitral valve insufficiency. Maximal enzyme activities were individually scaled by means of protein abundances in left ventricle tissue samples. The energy status of the left ventricle was quantified by the ATP consumption at rest (MVATP[rest]), at maximal workload (MVATP[max]), and by the myocardial ATP production reserve, representing the span between MVATP(rest) and MVATP(max). Results: Compared with controls, in both groups of patients, MVATP(rest) was increased and MVATP(max) was decreased, resulting in a decreased myocardial ATP production reserve, although all patients had preserved ejection fraction. The variance of the energetic status was high, ranging from decreased to normal values. In both patient groups, the energetic status was tightly associated with mechanic energy demand. A decrease of MVATP(max) was associated with a decrease of the cardiac output, indicating that cardiac functionality and energetic performance of the ventricle are closely coupled. Conclusions: Our analysis suggests that the ATP-producing capacity of the left ventricle of patients with valvular dysfunction is generally diminished and correlates positively with mechanical energy demand and cardiac output. However, large differences exist in the energetic state of the myocardium even in patients with similar clinical or image-based markers of hypertrophy and pump function. Registration: URL: https://www.clinicaltrials.gov; Unique identifiers: NCT03172338 and NCT04068740.

Animal studies show a pivotal role of dihydrotestosterone (DHT) in pressure overload-induced myocardial hypertrophy and dysfunction. The aim of our study was to evaluate the role of DHT levels and myocardial hypertrophy and myocardial protein expression in patients with severe aortic valve stenosis (AS). Forty-three patients [median age 68 (41-80) yr] with severe AS and indication for surgical aortic valve replacement (SAVR) were prospectively enrolled. Cardiac magnetic resonance imaging including analysis of left ventricular muscle mass (LVM), fibrosis and function, and laboratory tests including serum DHT levels were performed before and after SAVR. During SAVR, left ventricular (LV) biopsies were performed for proteomic profiling. Serum DHT levels correlated positively with indexed LVM (LVMi

Objectives:The aim of our study was to compare post-operative outcome after total cavopulmonary connection between patients operated during winter and summer season.Methods:We retrospectively studied 211 patients who underwent extracardiac total cavopulmonary connection completion at our institution between 1995 and 2015 (median age 4 (1–42) years). Seventy (33%) patients were operated during winter (November to March) and 141 (67%) patients during summer season (April to October).Results:Patients operated during winter and summer season showed no difference in early mortality (7% versus 5%, p = 0.52) and severe morbidity like need for early Fontan takedown (1% versus 1%, p = 0.99) and need for mechanical circulatory support (9% versus 4%, p = 0.12). The post-operative course and haemodynamic outcome were comparable between both groups of patients (ICU (4 versus 3 days, p = 0.44) and hospital stay (15 versus 14 days, p = 0.28), prolonged pleural effusions (36% versus 31%, p = 0.51), need for dialysis (16% versus 11%, p = 0.37), ascites (37% versus 33%, p = 0.52), supraventricular tachyarrhythmia (16% versus 13%, p = 0.56) and chylothorax (26% versus 16%, p = 0.12), change of antibiotic treatment (47% versus 36%, p = 0.06), prolonged inotropic support (24% versus 14%, p = 0.05), intubation time (15 versus 12 hours, p = 0.33), and incidence of fast-track extubation (11% versus 22%, p = 0.06).Conclusion:Outcomes after total cavopulmonary connection completion during winter and summer season were comparably related to mortality, severe morbidity, or longer hospital stay in the early post-operative period. These results suggest that total cavopulmonary connection completion during winter season is as safe as during summer season.

Objective. This study assesses age-related differences of thoracic aorta blood flow profiles and provides age- and sex-specific reference values using 4D flow cardiovascular magnetic resonance (CMR) data. Approach. 126 volunteers (age 20–80 years, female 51%) underwent 4D flow CMR and 12 perpendicular analysis planes in the thoracic aorta were specified. For these planes the following parameters were evaluated: body surface area-adjusted aortic area (A′), normalized flow displacement (NFD), the degree of wall parallelism (WPD), the minimal relative cross-sectional area through which 80% of the volume flow passes (A80) and the angle between flow direction and centerline (α). Main results. Age-related differences in blood flow parameters were seen in the ascending aorta with higher values for NFD and angle and lower values for WPD and A80 in older subjects. All parameters describing blood flow patterns correlated with the cross-sectional area in the ascending aorta. No relevant sex-differences regarding blood flow profiles were found. Significance. These age- and sex-specific reference values for quantitative parameters describing blood flow within the aorta might help to study the clinical relevance of flow profiles in the future.

Isolated repair of the regurgitant tricuspid aortic valve has become an increasingly practiced alternative to replacement, even though durability data are scarce. We analyzed the midterm results of tricuspid aortic valve repair to determine whether the mechanism of regurgitation or operative technique influences the results.Between December 1997 and August 2014, 264 patients underwent isolated tricuspid aortic valve repair in our institution. The mean age was 59 ± 16 years; 77% (n = 203) were male. Clinical and operative data were recorded. The patients were observed clinically and echocardiographically.Survival was 76.7% ± 3.5% after 10 years and 57.2% ± 11.5% after 15 years (median, 224 months). Intraoperative measurement of effective height was significantly associated with improved long-term survival (P = .001). Cumulative freedom from reoperation was 88.1% ± 2.1% after 5 years and 73.3% ± 4.2% after 10 years. Freedom from recurrent aortic regurgitation 2+ was 85.9% ± 5.2% after 5 years and 66.9% ± 5.2% after 10 years. Freedom from reoperation was significantly higher in patients with cusp prolapse compared with retraction as the primary regurgitation mechanism (P = .041). The use of circular annuloplasty had no significant influence on survival or durability.Long-term survival after tricuspid aortic valve repair is good, considering the age of the patients. Repair of cusp retraction has a poorer durability compared with repair of prolapse. The use of effective height in tricuspid aortic valve repair is associated with improved survival.

ObjectivesDespite the outstanding success of the Fontan operation, it is a palliative procedure and a substantial number of patients experience late failure of the Fontan circulation. Clinical presentation and hemodynamic phenotypes of Fontan failure are considerably variable. While various parameters have been identified as risk factors for late Fontan failure, a feasible score to classify Fontan failure and possibly allow timely risk stratification is lacking. Here, we explored the possibility of developing a score based on hemodynamic, clinical and laboratory parameters to classify Fontan failure and mortality.MethodsWe performed a retrospective study in our cohort of adult Fontan patients from two institutions [n = 198, median follow-up after Fontan 20.3 (IQR 15.6–24.3) years], identifying those patients with clinical Fontan failure (n = 52, 26.3%). Various hemodynamic, echocardiographic, laboratory and clinical data were recorded and differences between patients with and without Fontan failure were analyzed. We composed a Fontan Failure Score containing 15 parameters associated with Fontan failure and/or mortality and assessed its accuracy to discriminate between patients with and without late Fontan failure as well as late mortality and survival.ResultsLate failure occurred at a median of 18.2 (IQR 9.1–21.1) years after Fontan completion. Mortality associated with Fontan failure was substantial (25/52, 48.1%) with freedom of death/transplantation/take-down of 64% at 5 years and 36% at 10 years after onset of Fontan failure, respectively. Patients with Fontan failure had a significantly higher median Fontan Failure Score compared to non-failing Fontan patients [8 points (IQR 5–10) vs. 2 points (IQR 1-5), p < 0.001]. The score accurately classifies Fontan failure as well as mortality as assessed with receiver operating characteristic analysis. Area under the curve of the Fontan Failure Score was 0.963 (95% CI 0.921; 0.985, p < 0.001) to discriminate failure and 0.916 (95% CI 0.873; 0.959, p < 0.001) to classify mortality.ConclusionWe have developed an uncomplex yet remarkably accurate score to classify Fontan failure and late mortality in adult Fontan patients. Prospective validation and most likely refinement and calibration of the score in larger and preferably multi-institutional cohorts is required to assess its potential to predict the risk of Fontan failure and late mortality.

OBJECTIVES The Fontan operation aims at reducing cyanosis and cardiac volume overload in patients with complex univentricular heart malformations. However, persisting or reoccurring cyanosis is frequently observed. We sought to systematically determine the prevalence and clinical consequences of persisting and secondary cyanosis after Fontan operation. METHODS A total of 331 Fontan patients, operated between 1984 and 2016 with a median postoperative follow-up of 7.9 (interquartile range 2.6–15.8) years, were studied retrospectively. Cyanosis was defined as transcutaneous oxygen saturation ≤93% at rest measured by pulse oximetry. Prevalence of cyanosis was analysed at 3 different time points (t1 = post-Fontan operation, t2 = post-Fontan cardiac catheterization, t3 = last follow-up) and the association of cyanosis with mortality was examined. RESULTS Prevalence of cyanosis was 50% at t1 and 39% at t3. Fenestration was patent in 71% and 33% of all cyanotic patients at t1 and t3, respectively. In patients with clinical indication for catheterization (t2; n = 178/331), prevalence of cyanosis was 72%. At t2, patent fenestration (33%), veno-venous collaterals (24%) or both (32%) were present. Thirty-six (11%) patients died during follow-up. In a time-varying multivariable Cox regression analysis, cyanosis was the strongest predictor for late mortality (P CONCLUSIONS Prevalence of cyanosis was considerable during long-term follow-up after Fontan operation and—as a surrogate parameter for unfavourable Fontan haemodynamics—is associated with increased late mortality. Accordingly, particular attention should be directed towards the persistence or reoccurrence of cyanosis during follow-up since it may indicate haemodynamic attrition and development of Fontan failure.

Despite improved survival, surgical treatment of atrioventricular septal defect (AVSD) remains challenging. The optimal technique for primary left atrioventricular valve (LAVV) repair and prediction of suitability for biventricular approach in unbalanced AVSD are still controversial. We evaluated the ability of our recently developed echocardiographic left atrioventricular valve reduction index (LAVRI) in predicting LAVV reoperation rate and surgical strategy for unbalanced AVSD. Retrospective echocardiographic analysis was available in 352 of 790 patients with AVSD treated in our institution and included modified atrioventricular valve index (mAVVI), ventricular cavity ratio (VCR), and right ventricle/left ventricle (RV/LV) inflow angle. LAVRI estimates LAVV area after complete cleft closure and was analyzed with regard to surgical strategy in primary LAVV repair and unbalanced AVSD. Of the entire cohort, 284/352 (80.68%) patients underwent biventricular repair and 68/352 (19.31%) patients underwent univentricular palliation. LAVV reoperation was performed in 25/284 (8.80%) patients after surgical correction of AVSD. LAVRI was significantly lower in patients requiring LAVV reoperation (1.92 cm2/m2 [IQR 1.31] vs. 2.89 cm2/m2 [IQR 1.37], p = 0.002) and significantly differed between patients receiving complete and no/partial cleft closure (2.89 cm2/m2 [IQR 1.35] vs. 2.07 cm2/m2 [IQR 1.69]; p = 0.002). Of 82 patients diagnosed with unbalanced AVSD, 14 were suitable for biventricular repair (17.07%). mAVVI, LAVRI, VCR, and RV/LV inflow angle accurately distinguished between balanced and unbalanced AVSD and predicted surgical strategy (all p