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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.

OBJECTIVES Different types of patch materials are used for aortic valve repair in children with congenital aortic valve disease to avoid early valve replacement. CardioCel© (Admedus, Toowong, QLD, Australia) consists of bovine pericardium treated with the ADAPT method (Admedus’ proprietary tissue engineering process). METHODS Our goal was to describe tissue reactions in 12 explanted aortic valve leaflet specimens (augmented or replaced with CardioCel patch material) (11 explanted surgically, 1 autopsy). Explantation was performed during reoperation after aortic valve repair, necessitated by aortic valve stenosis in 5, aortic valve insufficiency in 2, combined aortic valve lesions in 3 patients and endocarditis in 1 patient. One patient died of sudden left heart failure 28 months after aortic valve repair. At the last documented follow-up of this patient at 22 months, he showed mild aortic valve stenosis and insufficiency. Implantation time (time between implantation and explantation) of CardioCel patches was a median of 25 (range 11–47) months. Explants were examined using a uniform protocol with methylmethacrylate and/or paraffin embedding after fixation in formalin. Besides standard histological staining, von Kossa (for identification of calcifications) and immunohistochemical stains were applied with antibodies specific for muscular, inflammatory and connective tissue component antigens. Findings regarding the extent of appositional growth on top of the patch consisting of fibroblasts and extracellular matrix components, calcification, and inflammation were rated using a 4-grade scale (G0 no/G1 few/G2 moderate/G3 massive). RESULTS Superficial endothelialization was demonstrated in all patients by immunohistochemical analysis. Nine specimens showed mild inflammatory cell infiltration (G1) (G2: n = 3). Significant appositional growth on top of the patch due to addition of fibroblasts and extracellular matrix components, was seen in all specimens (G1: n = 1; G2: n = 7; G3: n = 4). Ten of 12 samples with implant times of 23 months or longer revealed calcifications (G1: n = 6; G2: n = 3; G3: n = 1). Two specimens with the shortest implant times (11 and 20 months) showed no calcifications (G0). Thrombus apposition with granulocyte infiltration was demonstrated in the specimen of the patient with endocarditis. CONCLUSIONS In our cohort, all CardioCel patches used for aortic valve repair in patients with congenital heart disease demonstrated appositional growth of fibroblasts and extracellular matrix components, and calcification after an implant time of at least 23 months.

OBJECTIVES Complex blood flow profiles in the aorta are known to contribute to vessel dilatation. We studied flow profiles in the aorta in patients with aortic valve disease before and after surgical aortic valve replacement (AVR). METHODS Thirty-four patients with aortic valve disease underwent 4-dimensional velocity-encoded magnetic resonance imaging before and after AVR (biological valve = 27, mechanical valve = 7). Seven healthy volunteers served as controls. Eccentricity (ES) and complex flow scores (CFS) were determined from the degree of helicity, vorticity and eccentricity of flow profiles in the aorta. Model-based therapy planning was used in 4 cases to improve in silico postoperative flow profiles by personalized adjustment of size, rotation and angulation of the valve as well as aorta diameter. RESULTS Patients with aortic valve disease showed more complex flow than controls [median ES 2.5 (interquartile range (IQR) 2.3–2.7) vs 1.0 (IQR 1.0–1.0), P CONCLUSIONS Abnormal flow profiles in the aorta more frequently persist after surgical AVR. Model-based therapy planning might have the potential to optimize treatment for best possible individual outcome. Clinical trial registration number clinicaltrials.gov NCT03172338, 1 June 2017, retrospectively registered; NCT02591940, 30 October 2015, retrospectively registered.

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.

Modeling different treatment options before a procedure is performed is a promising approach for surgical decision making and patient care in heart valve disease. This study investigated the hemodynamic impact of different prostheses through patient-specific MRI-based CFD simulations. Ten time-resolved MRI data sets with and without velocity encoding were obtained to reconstruct the aorta and set hemodynamic boundary conditions for simulations. Aortic hemodynamics after virtual valve replacement with a biological and mechanical valve prosthesis were investigated. Wall shear stress (WSS), secondary flow degree (SFD), transvalvular pressure drop (TPD), turbulent kinetic energy (TKE), and normalized flow displacement (NFD) were evaluated to characterize valve-induced hemodynamics. The biological prostheses induced significantly higher WSS (medians: 9.3 vs. 8.6 Pa, P = 0.027) and SFD (means: 0.78 vs. 0.49, P = 0.002) in the ascending aorta, TPD (medians: 11.4 vs. 2.7 mm Hg, P = 0.002), TKE (means: 400 vs. 283 cm2 /s2 , P = 0.037), and NFD (means: 0.0994 vs. 0.0607, P = 0.020) than the mechanical prostheses. The differences between the prosthesis types showed great inter-patient variability, however. Given this variability, a patient-specific evaluation is warranted. In conclusion, MRI-based CFD offers an opportunity to assess the interactions between prosthesis and patient-specific boundary conditions, which may help in optimizing surgical decision making and providing additional guidance to clinicians.

In aortic coarctation (CoA), clinical guidelines recommend treatment in the presence of a relevant pressure gradient [(1)][1]. Although reliable noninvasive measurement approaches would be crucial, the accuracy of currently available methods is limited and cardiac catheterization has remained a

Aortic valve replacement (AVR) does not usually restore physiological flow profiles. Complex flow profiles are associated with aorta dilatation, ventricle remodeling, aneurysms, and development of atherosclerosis. All these affect long-term morbidity and often require reoperations. In this pilot study, we aim to investigate an ability to optimize the real surgical AVR procedure toward flow profile associated with healthy persons. Four cases of surgical AVR (two with biological and two with mechanical valve prosthesis) with available post-treatment cardiac magnetic resonance imaging (MRI), including four-dimensional flow MRI and showing abnormal complex post-treatment hemodynamics, were investigated. All cases feature complex hemodynamic outcomes associated with valve-jet eccentricity and strong secondary flow characterized by helical flow and recirculation regions. A commercial computational fluid dynamics solver was used to simulate peak systolic hemodynamics of the real post-treatment outcome using patient-specific MRI measured boundary conditions. Then, an attempt to optimize hemodynamic outcome by modifying valve size and orientation as well as ascending aorta size reduction was made. Pressure drop, wall shear stress, secondary flow degree, helicity, maximal velocity, and turbulent kinetic energy were evaluated to characterize the AVR hemodynamic outcome. The proposed optimization strategy was successful in three of four cases investigated. Although no single parameter was identified as the sole predictor for a successful flow optimization, downsizing of the ascending aorta in combination with the valve orientation was the most effective optimization approach. Simulations promise to become an effective tool to predict hemodynamic outcome. The translation of these tools requires, however, studies with a larger cohort of patients followed by a prospective clinical validation study.

SURVIVAL IMPROVEMENT in patients with congenital heart disease (CHD) has led to a growing number of adults living with CHD. 4D flow magnetic resonance imaging (MRI)1-5 has been used for the evaluation of various challenging CHD types. Quantitative measures of flow perturbations using 4D flow can aid in surveillance and treatment decision-making, and have been shown to be similar to standard clinical 2D phase-contrast (PC) MRI with acceptable test–retest repeatability.6-8 Using 4D flow, it is possible to assess flow volume in large thoracic vessels, comprising the pulmonary-systemic shunt ratio (Qp/Qs), shunt flow, peak flow, valvular regurgitant flow, and collateral flow volumes. Intracardiac flow patterns, including flow connectivity and distribution, pressure gradients, vortex/helical flow patterns, directionality, and turbulent and laminar energy losses can also be assessed. The aim of these recommendations from the ISMRM Flow & Motion Study Group is to standardize 4D flow in CHD with recommended acquisition, reconstruction, and postprocessing. This document focuses on CHD assessment with 4D flow, which requires, for example, coverage of a large volume in the thorax, and a wide range of velocities. Details on aortic 4D flow acquisitions can be found in the 2015 4D flow consensus statement.

Objectives Strict patient selection, short cardiopulmonary bypass (CPB) time and short mechanical ventilation are well-recognized aspects of optimizing the postoperative course after total cavopulmonary connection. In this study, we evaluated the influence of our early postoperative extubation strategy in our population of Fontan patients over the past 2 decades. Methods Early postoperative course was evaluated retrospectively in 211 consecutive patients, who were selected for total cavopulmonary connection in our institution between 1995 and 2015. We analysed postoperative haemodynamic parameters and early outcome after surgery (mortality and length of hospital stay) according to preoperative patient characteristics, duration of CPB and duration of mechanical ventilation. To investigate the influence of mechanical ventilation, the cohort was subdivided into a 'fast-track' extubation group (≤6 h ventilation, n = 59) and a prolonged ventilation group (>6 h ventilation, n = 152). Results In the entire cohort, duration of CPB did not correlate with duration of mechanical ventilation (P = 0.1), and it did not differ between both groups (P = 0.3). Patients in the fast-track group showed significantly better haemodynamics with higher mean arterial pressure and lower mean pulmonary artery pressure at 6, 24 and 48 h postoperatively when compared with the prolonged ventilation group (P = 0.02-0.001). In multivariable analysis, longer mechanical ventilation, but not duration of CPB, was independently associated with length of hospital stay. Conclusions Early weaning from mechanical ventilation correlates with improved early Fontan haemodynamics, whereas early outcome is unrelated to duration of CPB. This indicates that early extubation may represent a principal strategy for improving early results after total cavopulmonary connection.

Objectives The search for an optimal patch material for aortic valve reconstruction (AVR) is an ongoing challenge. In this study, we report our experience of AVR using decellularized bovine pericardial patch material in congenital heart surgery. Methods Data of 40 consecutive patients who underwent AVR using the CardioCel® patch (Admedus Regen Pty Ltd, Perth, WA, Australia) between February 2014 and August 2016 were retrospectively reviewed. The median age of the patients at operation was 9 (2-34) years, and 18 patients were younger than 7 years. Twenty-six patients initially presented with aortic valve insufficiency (AI) and 14 with stenosis. Clinical and echocardiographic data were available until August 2017 for a median postoperative follow-up (FU) of 22 (6-42) months. Results Nine of 40 (23%) patients experienced an event during FU (death: n = 1, 2.5%; reoperation: n = 8, 20%). Overall, the probability of freedom from reoperation or death was 97 ± 3%, 76 ± 9% and 57 ± 12% at 12, 24 and 36 months of FU, respectively. Reason for reoperation was stenosis in 3 (37.5%) patients, insufficiency in 4 (50%) patients and 1 (12.5%) patient was diagnosed with aortic valve endocarditis. Of the remaining 31 patients, 2 patients are scheduled for reoperation (aortic valve stenosis: n = 1 and AI: n = 1) and 9 patients exhibit worsening of aortic valve function with moderate AI. Freedom from developing combined end point [death/reoperation/moderate degree of aortic valve dysfunction (aortic valve stenosis, AI)] after AVR was 92 ± 5%, 55 ± 9% and 28 ± 9% at 12, 24 and 36 months, respectively. Conclusions AVR using decellularized bovine pericardial patch material in patients with congenital aortic valve disease show unsatisfactory results within the first 3 years of FU.

BackgroundWe sought to assess left ventricular regional function in patients with and without left ventricular wall scar tissue in the long term after repair of an anomalous origin of the left coronary artery from the pulmonary artery.MethodsA total of 20 patients aged 12.8±7.4 years were assessed 10 (0.5–17) years after the repair of an anomalous origin of the left coronary artery from the pulmonary artery; of them, 10 (50%) patients showed left ventricular wall scar tissue on current cardiac MRI. Left ventricular regional function was assessed by two-dimensional speckle-tracking echocardiography in 10 patients with scar tissue and 10 patients without scar tissue and in 10 age-matched controls.ResultsIn patients with scar tissue, MRI-derived left ventricular ejection fraction was significantly reduced compared with that in patients without scar tissue (51 versus 61%, pConclusionsRegional left ventricular function is reduced even in patients without left ventricular wall scar tissue late after successful repair of an anomalous origin of the left coronary artery from the pulmonary artery. This highlights the need for meticulous lifelong follow-up in all patients with a repaired anomalous origin of the left coronary artery from the pulmonary artery.

Background In aortic coarctation, current guidelines recommend reducing pressure gradients that exceed given thresholds. From a physiological standpoint this should ideally improve the energy expenditure of the heart and thus prevent long term organ damage. Objectives The aim was to assess the effects of interventional treatment on external and internal heart power (EHP, IHP) in patients with aortic coarctation and to explore the correlation of these parameters to pressure gradients obtained from heart catheterization. Methods In a collective of 52 patients with aortic coarctation 25 patients received stenting and/or balloon angioplasty, and 20 patients underwent MRI before and after an interventional treatment procedure. EHP and IHP were computed based on catheterization and MRI measurements. Along with the power efficiency these were combined in a cardiac energy profile. Results By intervention, the catheter gradient was significantly reduced from 21.8±9.4 to 6.2±6.1mmHg (p

Background and objectivesFlow profiles are important determinants of fluid–vessel wall interactions. The aim of this study was to assess blood flow profiles in the aorta and pulmonary trunk in patients with transposition and different ventriculoarterial connection, and hence different mechanics of the coherent pump.MethodsIn all, 29 patients with operated transposition – concordant atrioventricular and discordant ventriculoarterial connection, and no other cardiac malformation – and eight healthy volunteers were assessed with cardiac magnetic resonance imaging: n = 17 patients after atrial redirection, with a morphologic right ventricle acting as systemic pump and a morphologic left ventricle connected to the pulmonary trunk, and n = 12 patients after the arterial switch procedure, with physiologic ventriculoarterial connections. Flow-sensitive four-dimensional velocity-encoded magnetic resonance imaging was used to analyse systolic flow patterns in the aorta and pulmonary trunk, relating to helical flow and vortex formation.ResultsIn the aorta, overall helicity was present in healthy volunteers, but it was absent in all patients independent on the operation technique. Partial helices were observed in the ascending aorta of 58% of patients after arterial switch. In the pulmonary trunk, mostly parallel flow was seen in healthy volunteers and in patients after arterial switch, whereas vortex formation was present in 88% of patients after atrial redirection.ConclusionBlood flow patterns differ substantially between the groups. In addition to varying mechanics of the coherent pumping ventricles, the absent overall helicity in all patients might be explained by the missing looping of the aorta in transposition.

Modeling different treatment options before a procedure is performed is a promising approach for surgical decision making and patient care in heart valve disease. This study investigated the hemodynamic impact of different prostheses through patient-specific MRI-based CFD simulations. Ten time-resolved MRI data sets with and without velocity encoding were obtained to reconstruct the aorta and set hemodynamic boundary conditions for simulations. Aortic hemodynamics after virtual valve replacement with a biological and mechanical valve prosthesis were investigated. Wall shear stress (WSS), secondary flow degree (SFD), transvalvular pressure drop (TPD), turbulent kinetic energy (TKE), and normalized flow displacement (NFD) were evaluated to characterize valve-induced hemodynamics. The biological prostheses induced significantly higher WSS (medians: 9.3 vs. 8.6 Pa, P = 0.027) and SFD (means: 0.78 vs. 0.49, P = 0.002) in the ascending aorta, TPD (medians: 11.4 vs. 2.7 mm Hg, P = 0.002), TKE (means: 400 vs. 283 cm

Optimizing treatment planning is essential for advances in patient care and outcomes. Precisely tailored therapy for each patient remains a yearned-for goal. Cardiovascular modelling has the potential to simulate and predict the functional response before the actual intervention is performed. The objective of this study was to proof the validity of model-based prediction of haemodynamic outcome after aortic valve replacement. In a prospective study design virtual (model-based) treatment of the valve and the surrounding vasculature were performed alongside the actual surgical procedure (control group). The resulting predictions of anatomic and haemodynamic outcome based on information from magnetic resonance imaging before the procedure were compared to post-operative imaging assessment of the surgical control group in ten patients. Predicted vs. post-operative peak velocities across the valve were comparable (2.97 ± 1.12 vs. 2.68 ± 0.67 m/s; p = 0.362). In wall shear stress (17.3 ± 12.3 Pa vs. 16.7 ± 16.84 Pa; p = 0.803) and secondary flow degree (0.44 ± 0.32 vs. 0.49 ± 0.23; p = 0.277) significant linear correlations (p

Purpose: To evaluate the use of four-dimensional (4D) velocity-encoded magnetic resonance imaging (VEC MRI) for blood flow quantification in patients with semilunar valve stenosis and complex accelerated flow. Materials and Methods: Peak velocities (Vmax) and stroke volumes (SV) were quantified by 2D and 4D VEC MRI in volunteers (n = 7) and patients with semilunar valve stenosis (n = 18). Measurements were performed above the aortic and pulmonary valve with both techniques and, additionally, at multiple predefined planes in the ascending aorta and in the pulmonary trunk within the 4D dataset. In patients, 4D VEC MRI streamline analysis identified flow patterns and regions of highest flow velocity (4Dmax-targeted) for further measurements and Vmax was also measured by Doppler-echocardiography. Results: In patients, 4D VEC MRI showed higher Vmax than 2D VEC MRI (2.7 ± 0.6 m/s vs. 2.4 ± 0.5 m/s, P < 0.03) and was more comparable to Doppler-echocardiography (2.8 ± 0.7 m/s). 4Dmax-targeted revealed highest Vmax values (3.1 ± 0.6 m/s). SV measurements showed significant differences between different anatomical levels in the ascending aorta in patients with complex accelerated flow, whereas differences in volunteers with laminar flow patterns were negligible (P = 0.004). Conclusion: 4D VEC MRI improves MRI-derived blood flow quantification in patients with semilunar valve stenosis and complex accelerated flow. J. Magn. Reson. Imaging 2013;37:208–216. © 2012 Wiley Periodicals, Inc.

Objective Although mortality after direct aortic reimplantation for anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) has significantly decreased, many questions remain unanswered. Methods Between 1986 and June 2010, we operated on 27 consecutive pediatric patients with anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA). All patients underwent reestablishment of a dual coronary system with direct aortic reimplantation of the left coronary artery into the aorta. Postoperative extracorporeal mechanical circulatory support was necessary in 7 cases. In all 7 patients, hemodynamic stability was achieved after 4 to 10 days of support. Mitral valve repair was performed in 9 patients with severe mitral valve incompetence and resulted in stable mitral valve function during follow-up as long as 19 years. Results There were no early or late deaths. During follow-up (3 months–17.5 years), both early and late improvement of myocardial function was observed in all patients. Reduced left ventricular regional function late after successful surgical correction of ALCAPA was related to the presence of left ventricular myocardial scar tissue, as detected by magnetic resonance imaging. Conclusions Despite the absence of early and late mortality, the long-term prognosis for patients after reimplantation of ALCAPA into the aorta is not clear. Scars and perfusion deficits of the left ventricle may not be detected by standard echocardiographic evaluation of global left ventricular function and therefore may be underestimated. We therefore recommend lifelong surveillance of these patients, including magnetic resonance imaging.

ObjectivesTo assess if flow-sensitive four-dimensional velocity-encoded cine magnetic resonance imaging adds value in diagnosing patients with suspected partial anomalous pulmonary venous drainage.MethodsIn six patients with echocardiographically suspected partial anomalous pulmonary venous drainage, anatomy was evaluated using standard magnetic resonance imaging including angiography. Functional analysis included shunt calculations from flow measurements. We used four-dimensional velocity-encoded cine magnetic resonance imaging for visualisation of maldraining pulmonary veins and quantification of flow via the maldraining veins and interatrial communications, if present.ResultsIn all patients, the diagnosis of partial anomalous pulmonary venous drainage was confirmed by standard magnetic resonance imaging. Shunt volumes ranged from 1.4:1 to 4.7:1. Drainage sites were the superior caval vein (n = 5) or the vertical vein (n = 1). Multiple maldraining pulmonary veins were found in three patients. Pulmonary arteries and veins could be clearly distinguished by selective visualisation using four-dimensional velocity-encoded cine magnetic resonance imaging. Flow measured individually in maldraining pulmonary veins in six patients and across the interatrial communication in three patients revealed a percentage of the overall shunt volume of 30–100% and 58–70%, respectively.ConclusionSelective visualisation of individual vessels and their flow characteristics by four-dimensional velocity-encoded cine magnetic resonance imaging facilitates in distinguishing adjacent pulmonary arteries and veins and thus improves the accurate diagnosis of maldraining pulmonary veins. By detailed quantification of shunt volumes, additional information for planning of treatment strategies is provided. This method adds clinical value and might replace contrast-enhanced magnetic resonance angiography in these patients in the future.

Purpose: To further validate the quantitative use of flow-sensitive four-dimensional velocity encoded cine magnetic resonance imaging (4D VEC MRI) for simultaneously acquired venous and arterial blood flow in healthy volunteers and for abnormal flow in patients with congenital heart disease. Materials and Methods: Stroke volumes (SV) obtained in arterial and venous thoracic vessels were compared between standard two-dimensional (2D), 4D VEC MRI with and without respiratory navigator gating (gated/nongated) in volunteers (n = 7). In addition, SV and regurgitation fractions (RF) measured in aorta or pulmonary trunk of patients with malformed and/or insufficient valves (n = 10) were compared between 2D and nongated 4D VEC MRI methods. Results: In volunteers and patients, Bland–Altman tests showed excellent agreement between 2D, gated, and nongated 4D VEC MRI obtained quantitative blood flow measurements. The bias between 2D and gated 4D VEC MRI was

Background Left ventricular (LV) mechanical circulatory support (MCS) may be necessary after repair of anomalous left coronary artery from the pulmonary artery. We evaluated LV function parameters for their ability to predict postoperative need for MCS. Methods Fourteen infants (median age, 3.6; range, 2.3 to 12 months) underwent direct aortic reimplantation of the left coronary artery. We compared preoperative LV end-diastolic diameter, end-diastolic pressure, ejection fraction, and fraction of shortening of 8 patients with successful weaning from cardiopulmonary bypass (group 1) and 6 patients with unsuccessful weaning from cardiopulmonary bypass and temporary MCS support (group 2). Results No perioperative or late deaths occurred. All patients at follow-up were free of reoperation (median follow-up, 10.4 years [range, 1.4 to 17 years]). Median preoperative LV end-diastolic diameter (47 [range, 41 to 60 mm] vs 32 mm [range, 21 to 36 mm]) and LV end-diastolic pressure (20 [range, 18 to 25 mm Hg] vs 12 mm Hg [range, 7 to 20 mm Hg]) were significantly higher in group 2 than in group 1 ( p = 0.002 and p = 0.048). LV ejection fraction (0.28 [range, 0.19 to 0.37] vs 0.43 [range, 0.23 to 0.76]) and LV fraction of shortening (9% [range, 7% to 15%] vs 22% [range 13% to 30%]) were significantly lower in group 2 than in group 1 ( p = 0.035 and p = 0.002). MCS support duration ranged from 4 to 12 days. There were no significant differences in LV function parameters at discharge or during follow-up between the groups. Conclusions A preoperative LV end-diastolic diameter above 40 mm is the strongest predictor for postoperative temporary MCS after anomalous left coronary artery from the pulmonary artery repair in infancy. However, even with temporary MCS, direct aortic reimplantation for anomalous left coronary artery from the pulmonary artery can be performed with no mortality and excellent LV recovery.

Background Anomalous left coronary artery from the pulmonary artery (ALCAPA) is a rare congenital heart defect. We aimed to examine the role of cardiac magnetic resonance imaging (MRI) in the long-term surveillance of repaired ALCAPA with regard to myocardial scarring, wall motion abnormalities, perfusion deficits, and myocardial function. Methods Twenty-one patients after direct reimplantation of ALCAPA (median age at operation, 2.8 years) were examined after a median 10.6 years by MRI at rest and under dobutamine stress conditions, echocardiography, and ergometry. Results were compared with preoperative, immediately postoperative (5 days), and intermediate-term (5.8 years) echocardiography. Results No early or late deaths occurred. Improvements in indexed left ventricular end-diastolic dimension, ejection fraction, and mitral valve function were observed in all patients. However, MRI at rest showed wall motion abnormalities in 67% and perfusion deficits in 28%. Myocardial scars were seen in 67%. Dobutamine stress MRI detected wall motion abnormalities in 19% and perfusion deficits in 14%, which were not seen on MRI at rest. Exercise testing did not reflect cardiac dysfunction. Conclusions Although long-term follow-up showed global left ventricular function had improved after ALCAPA repair, MRI showed left ventricular wall motion abnormalities, perfusion deficits, and myocardial scarring were seen in many patients. Dobutamine stress MRI identified deficits that were not evident on MRI at rest, and can therefore be considered a valuable surveillance tool. These results suggest the need for lifelong surveillance of repaired ALCAPA.

To validate the use of particle traces derived from four-dimensional (4D) flow magnetic resonance (MR) imaging to quantify in vivo the caval flow contribution to the pulmonary arteries (PAs) in patients who had been treated with the Fontan procedure.The institutional review boards approved this study, and informed consent was obtained. Twelve healthy volunteers and 10 patients with Fontan circulation were evaluated. The particle trace method consists of creating a region of interest (ROI) on a blood vessel, which is used to emit particles with a temporal resolution of approximately 40 msec. The flow distribution, as a percentage, is then estimated by counting the particles arriving to different ROIs. To validate this method, two independent observers used particle traces to calculate the flow contribution of the PA to its branches in volunteers and compared it with the contribution estimated by measuring net forward flow volume (reference method). After the method was validated, caval flow contributions were quantified in patients. Statistical analysis was performed with nonparametric tests and Bland-Altman plots. P.05 was considered to indicate a significant difference.Estimation of flow contributions by using particle traces was equivalent to estimation by using the reference method. Mean flow contribution of the PA to the right PA in volunteers was 54% ± 3 (standard deviation) with the reference method versus 54% ± 3 with the particle trace method for observer 1 (P = .4) and 54% ± 4 versus 54% ± 4 for observer 2 (P = .6). In patients with Fontan circulation, 87% ± 13 of the superior vena cava blood flowed to the right PA (range, 63%-100%), whereas 55% ± 19 of the inferior vena cava blood flowed to the left PA (range, 22%-82%).Particle traces derived from 4D flow MR imaging enable in vivo quantification of the caval flow distribution to the PAs in patients with Fontan circulation. This method might allow the identification of patients at risk of developing complications secondary to uneven flow distribution.http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.12120778/-/DC1.

Background— The concentration of gadopentetate dimeglumine in myocardium and blood can be assessed from T1 measurements and can be used to calculate the extracellular volume (ECV) of the myocardium. We hypothesized that diffuse myocardial fibrosis in a small-animal model could be quantitatively assessed by measuring myocardial ECV using small-animal Look-Locker inversion recovery T1 mapping. Methods and Results— Sprague-Dawley rats (n=10) were subjected to continuous angiotensin-2 (AT2) infusion for 2 weeks via a subcutaneously implanted minipump system. Magnetic resonance imaging (MRI) was performed both before and after AT2 infusion. The MRI protocol included multislice cine imaging and before-and-after contrast small-animal Look-Locker inversion recovery T1 mapping and late gadolinium enhancement imaging. Myocardial ECV was calculated from hematocrit and T1 values of blood and myocardium. During the course of AT2 infusion, the mean±SD systolic blood pressure increased from 122±10.9 to 152±27.5 mm Hg ( P =0.003). Normalized heart weight was significantly higher in AT2-treated animals than in control littermates ( P =0.033). Cine MRI documented concentric left ventricular hypertrophy. Postcontrast myocardial T1 times were shortened after treatment (median [interquartile range], 712 [63] versus 820 [131] ms; P =0.002). Myocardial ECV increased from 17.2% (4.3%) before to 23.0% (6.2%) after AT2 treatment ( P =0.031), which was accompanied by perivascular fibrosis and microscarring on myocardial histological analysis. There was a moderate level of correlation between ECV and collagen volume fraction, as assessed by histological analysis ( r =0.69, P =0.013). Conclusions— In a small-animal model of left ventricular hypertrophy, contrast-enhanced T1 mapping can be used to detect diffuse myocardial fibrosis by quantification of myocardial ECV.

To develop a single magnetic resonance (MR) imaging approach for comprehensive assessment of cardiac function and tissue properties in small animals with high heart rates.All animal studies were approved by the local animal care committee. Small animal Look-Locker inversion recovery (SALLI) was implemented on a clinical 3.0-T MR unit equipped with a 70-mm solenoid coil. SALLI combines a segmented, electrocardiographically gated, inversion recovery-prepared Look-Locker-type pulse sequence with a multimodal reconstruction framework. Temporal undersampling and radial nonbalanced steady-state free precession enabled acceleration of data acquisition and reduction of motion artifacts, respectively. Nine agarose gel phantoms were used to investigate different sequence settings. For in vivo studies, 10 Sprague-Dawley rats were evaluated to establish normal T1 values before and after injection of gadopentetate dimeglumine. Seven rats with surgically induced acute myocardial infarction were examined to test the feasibility of detecting myocardial injury. In vitro T1 behavior was studied with linear regression analysis, and in vivo T1 differences between infarcted and remote areas were tested by using the Wilcoxon signed rank test.Phantom studies demonstrated systematic behavior of the T1 measurements, and T1 error could be reduced to 1.3% ± 7.4 by using a simple linear correction algorithm. The pre- and postcontrast T1 of myocardium and blood showed narrow normal ranges. In the area of infarction, SALLI demonstrated hypokinesia (on cine images), myocardial edema (on precontrast T1 maps), and myocardial necrosis (on postcontrast T1 maps and late gadolinium enhancement images).An MR imaging method enabling simultaneous generation of cardiac T1 maps and cine and inversion recovery-prepared images at high heart rates is presented. SALLI allows for simultaneous and time-efficient assessment of cardiac T1 behavior, function, and late gadolinium enhancement at high heart rates.

Failing Fontan circulation is a multifactorial problem without clear predictors and with uncertain onset. We sought to investigate the correlations between systemic venous flow return and the clinical condition of Fontan patients.Flow measurements using phase contrast magnetic resonance imaging (MRI) were performed in the superior and inferior vena cava (SVC, IVC) in 61 Fontan patients. Median postoperative follow-up time was 6.7 (0.6-14.1) years; median age at MRI was 11.6 (4.0-44.6) years. Eight patients were identified clinically as a subgroup with suboptimal hemodynamics. The effective forward flow of combined SVC and IVC flow volume was defined as the venous cardiac index (vCI, l/min/m(2)). SVC flow ratio was defined as SVC flow in relation to vCI. The vCI and flow distribution between the SVC and IVC were investigated in relation to the hemodynamics and patients' age at MRI.Venous flow return through the SVC was 1.1 (0.6-3.4) l/min/m(2) and through the IVC 1.8 (0.6-3.2) l/min/m(2); total vCI was 3 l/min/m(2) (1.2-5.1). Patients with suboptimal Fontan hemodynamics showed significantly lower IVC flow return (median of 1.5 vs. 1.9 l/min/m(2), p = 0.027) and increased SVC flow ratio (0.56 vs. 0.35, p = 0.005) in comparison to those with good clinical condition. The total vCI decrease was correlated with older patient age (r = 0.575, p 0.001).Altered systemic venous flow return is associated with suboptimal Fontan hemodynamics and seems to progress with patients' age and long-term follow-up after Fontan operation. Thus, MRI flow volume measurements might help in monitoring Fontan patients before the onset of clinical signs of suboptimal hemodynamics.

Materials and methods Maximal flow velocities (Vmax) and flow volumes (SV) were quantified by 2D and 4D VEC MRI in healthy volunteers (n=7) and patients with aortic (n=7) or pulmonary valve stenosis (n=10). Measurements were performed immediately above the aortic or pulmonary valve (=level 1). Using 4D VEC MRI additional measurements were performed at 3 further levels in the ascending aorta (levels 2-4) and at 2 in the MPA (levels 2-3). In each patient flow volumes measured in the nonpathologic MPA or Aorta served as internal control for expected flow volumes in the absence of shunt flow.

Methods In six patients with echocardiographically suspected PAPVD, anatomy was evaluated using standard magnetic resonance imaging including angiography. Functional analysis included shunt calculations from standard flowmeasurements. Furthermore, 4D VEC MRI was used for visualization of maldraining pulmonary veins and quantification of flow via the maldraining veins and interatrial communications, if present.

Cardiac T1 mapping allows for quantitative analysis of myocardial tissue properties. Pulse sequences for human applications are not suitable for in-vivo studies in small animals.The aim of this study was to develop a single magnetic resonance imaging (MRI) approach for comprehensive assessment of cardiac function and tissue properties in small animals with high heart rates.