Infective endocarditis with or without congenital heart disease: clinical features and outcomes.

BACKGROUND AND AIMS: Patients with congenital heart disease (CHD) form a high-risk subgroup for infective endocarditis (IE), necessitating tailored prevention and treatment strategies. However, comprehensive nationwide data comparing IE characteristics and outcomes in patients with and without CHD, including children, are sparse. This study aims to address this gap in knowledge. METHODS: Using Danish nationwide registries, all patients with IE from 1977 to 2021 were identified and stratified on whether they had a diagnosis of CHD, regardless of its complexity. Characteristics prior to and during admission as well as associated outcomes (i.e. in-hospital mortality, 1-year mortality, and 10-year mortality, and IE recurrence) were compared between groups. RESULTS: In total, 14 040 patients with IE were identified, including 895 (6.4%) with CHD. Patients with vs. without CHD were younger at the time of IE diagnosis (median age 38.8 vs. 70.7 years), less comorbid, and more frequently underwent cardiac surgery during admission (35.7% vs. 23.0%, P < .001). Notably, 76% of patients with IE < 18 years of age had CHD. The IE-related bacteraemia differed between groups: Streptococci (29.9%) were the most common in patients with CHD, and Staphylococcus aureus (29.9%) in patients without CHD. Patients with CHD had a significantly lower cumulative incidence of in-hospital mortality (5.7% vs. 17.0%, P < .001) and 1-year mortality (9.9% vs. 31.8%, P < .001) compared with those without CHD. The 10-year cumulative incidence of IE recurrence was similar between groups (13.0% and 13.9%, P = .61). CONCLUSIONS: Patients with CHD who develop IE exhibit distinct characteristics and improved long-term outcomes compared with patients without CHD. Notably, the majority of children and adolescents with IE have underlying CHD.

Arrhythmias in Congenital Heart Disease: a Nationwide Cohort Study.

BACKGROUND: As more patients with congenital heart disease (CHD) survive into adulthood, the population of adults with CHD is expanding. This trend is accompanied by an increasing incidence of complications, including arrhythmias. However, the long-term risk of arrhythmias remains sparsely investigated. METHODS: In this observational cohort study, all Danish patients with CHD born from 1977 to 2024 were identified using registries and followed from date of birth until the occurrence of arrhythmia, emigration, death, or end of follow-up (March 2024). The risk of arrhythmias was assessed among patients with CHD and compared to age- and sex-matched controls from the background population. RESULTS: A total of 45,820 patients with CHD (50.9% men) were identified and matched with 183,280 controls from the background population. During a median follow-up of 21.5 years, 2.6% of patients with CHD and 0.2% of controls developed arrhythmias - corresponding to incidence rates (IR) of 1.2 (95%CI 1.2-1.3) and 0.1 (95%CI 0.1-0.1) per 1,000 PY, respectively, and a hazard ratio (HR) of 16.4 (95%CI 14.4-18.7). The most common arrhythmias in patients with CHD were advanced atrioventricular block (IR 0.4 [95%CI 0.4-0.4] per 1,000 PY) and atrial flutter/fibrillation (IR 0.5 [95%CI 0.5-0.6] per 1,000 PY). Patients with malformations of the heart chambers, transposition of the great arteries, tetralogy of Fallot, and atrioventricular septal defect were at the highest risk of arrhythmias. Moreover, the risk of arrhythmias among those with ASD was not negligible. In patients with CHD, arrhythmia was associated with a significantly higher risk of death (HR of 6.9 [95%CI 5.9-8.1]). CONCLUSIONS: Patients with CHD are at significantly higher risk of arrhythmias than the background population, and those with complex CHD are at particularly high risk. In patients with CHD, arrhythmia is associated with an increased risk of death. Additional studies are warranted to investigate how we can improve the diagnosis and management of arrhythmias in CHD.

Implantable cardioverter defibrillator therapy in paediatric patients for primary vs. secondary prevention.

AIMS: The decisions about placing an ICD in a child are more difficult than in an adult due to longer expected lifespan and the complication risk. Young patients gain the most years from ICDs, despite higher risk of device-related complications. The secondary prevention ICD indication is clear, and device is implanted regardless of potential complications. For primary prevention, risk of sudden cardiac death and complications need to be evaluated. We aimed to compare outcomes for primary and secondary prevention ICDs. METHODS AND RESULTS: Retrospective nationwide cohort study including paediatric patients identified from the Danish ICD registry with ICD implanted at an age ≤ 15 from 1982-21. Demographics, complications (composite of device-related infections or lead-failure requiring re-operation, mortality because of arrhythmia, or unknown cause), and mortality were retrieved from medical charts. Endpoint was appropriate therapy (shock or anti-tachycardia pacing for ventricular tachycardia or fibrillation). Of 72 receiving an ICD, the majority had channelopathies (n = 34) or structural heart diseases (n = 28). ICDs were implanted in 23 patients for primary prevention and 49 for secondary prevention, at median ages of 13.8 and 11.6 years (P-value 0.01), respectively. Median follow-up was 9.0 (interquartile ranges: 4.7-13.5) years. The 10-year cumulative incidence of first appropriate therapy was 70%, with complication and inappropriate therapy rates at 41% and 15%, respectively. No difference was observed between prevention groups for all outcomes. Six patients died during follow-up. CONCLUSION: In children, two-thirds are secondary prevention ICDs. Children have higher appropriate therapy and complication rates than adults, while the inappropriate therapy rate was low.

Influence of Cardiovascular Risk Factors, Comorbidities, Medication Use and Procedural Variables on Remote Ischemic Conditioning Efficacy in Patients with ST-Segment Elevation Myocardial Infarction.

Remote ischemic conditioning (RIC) confers cardioprotection in patients with ST-segment elevation myocardial infarction (STEMI). Despite intense research, the translation of RIC into clinical practice remains a challenge. This may, at least partly, be due to confounding factors that may modify the efficacy of RIC. The present review focuses on cardiovascular risk factors, comorbidities, medication use and procedural variables which may modify the efficacy of RIC in patients with STEMI. Findings of such efficacy modifiers are based on subgroup and post-hoc analyses and thus hold risk of type I and II errors. Although findings from studies evaluating influencing factors are often ambiguous, some but not all studies suggest that smoking, non-statin use, infarct location, area-at-risk of infarction, pre-procedural Thrombolysis in Myocardial Infarction (TIMI) flow, ischemia duration and coronary collateral blood flow to the infarct-related artery may influence on the cardioprotective efficacy of RIC. Results from the on-going CONDI2/ERIC-PPCI trial will determine any clinical implications of RIC in the treatment of patients with STEMI and predefined subgroup analyses will give further insight into influencing factors on the efficacy of RIC.

Influence of long-term treatment with glyceryl trinitrate on remote ischemic conditioning.

Remote ischemic conditioning (RIC) protects against sustained myocardial ischemia. Because of overlapping mechanisms, this protection may be altered by glyceryl trinitrate (GTN), which is commonly used in the treatment of patients with chronic ischemic heart disease. We investigated whether long-term GTN treatment modifies the protection by RIC in the rat myocardium and human endothelium. We studied infarct size (IS) in rat hearts subjected to global ischemia-reperfusion (I/R) in vitro and endothelial function in healthy volunteers subjected to I/R of the upper arm. In addition to allocated treatment, rats were coadministered with reactive oxygen species (ROS) or nitric oxide (NO) scavengers. Rats and humans were randomized to 1) control, 2) RIC, 3) GTN, and 4) GTN + RIC. In protocols 3 and 4, rats and humans underwent long-term GTN treatment for 7 consecutive days, applied subcutaneously or 2 h daily transdermally. In rats, RIC and long-term GTN treatment reduced mean IS (18 ± 12%, P = 0.007 and 15 ± 5%, P = 0.002) compared with control (35 ± 13%). RIC and long-term GTN treatment in combination did not reduce IS (29 ± 12%, P = 0.55 vs. control). ROS and NO scavengers both attenuated IS reduction by RIC and long-term GTN treatment. In humans, I/R reduced endothelial function ( P = 0.01 vs. baseline). Separately, RIC and long-term GTN prevented the reduction in endothelial function caused by I/R; given in combination, prevention was lost. RIC and long-term GTN treatment both protect against rat myocardial and human endothelial I/R injury through ROS and NO-dependent mechanisms. However, when given in combination, RIC and long-term GTN treatment fail to confer protection. NEW & NOTEWORTHY Remote ischemic conditioning (RIC) and long-term glyceryl trinitrate (GTN) treatment protect against ischemia-reperfusion injury in both human endothelium and rat myocardium. However, combined application of RIC and long-term GTN treatment abolishes the individual protective effects of RIC and GTN treatment on ischemia-reperfusion injury, suggesting an interaction of clinical importance.

Effect of remote ischemic conditioning on myocardial perfusion in patients with suspected ischemic coronary artery disease.

BACKGROUND: Remote ischemic conditioning (RIC) confers protection against myocardial ischemia-reperfusion injury and may modulate coronary blood flow. We investigated whether RIC affects resting myocardial perfusion (MP) in patients with suspected ischemic coronary artery disease by quantitative MP imaging. METHODS AND RESULTS: We included 49 patients with suspected ischemic coronary artery disease. Resting MP was quantified by 82Rubidium positron emission tomography/computed tomography (82Rb-PET/CT) imaging before and after RIC, performed as four cycles of 5 minutes upper arm ischemia and reperfusion. Subsequent adenosine 82Rb-PET/CT stress-imaging identified non-ischemic and reversibly ischemic myocardial segments. MicroRNA-144 plasma levels were measured before and after RIC. Normalized for rate pressure product, RIC did not affect MP globally (P = .64) or in non-ischemic myocardial segments (P = .58) but decreased MP in reversibly ischemic myocardial segments (-0.11 mL/min/g decrease in MP following RIC; 95% CI -0.17 to -0.06, P < .001). However, we found no effect of RIC when MP was normalized for cardiac work. MicroRNA-144 plasma levels increased following RIC (P = .006) but did not correlate with a change in global MP in response to RIC (P = .40). CONCLUSIONS: RIC did not substantially affect resting MP globally or in non-ischemic and reversibly ischemic myocardial territories in patients with suspected ischemic coronary artery disease.

Effect of long-term remote ischemic conditioning in patients with chronic ischemic heart failure.

Remote ischemic conditioning (RIC) protects against acute ischemia-reperfusion injury and may also have beneficial effects in patients with stable cardiovascular disease. We investigated the effect of long-term RIC treatment in patients with chronic ischaemic heart failure (CIHF). In a parallel group study, 22 patients with compensated CIHF and 21 matched control subjects without heart failure or ischemic heart disease were evaluated by cardiac magnetic resonance imaging, cardiopulmonary exercise testing, skeletal muscle function testing, blood pressure measurement and blood sampling before and after 28 ± 4 days of once daily RIC treatment. RIC was conducted as four cycles of 5 min upper arm ischemia followed by 5 min of reperfusion. RIC did not affect left ventricular ejection fraction (LVEF) or global longitudinal strain (GLS) in patients with CIHF (p = 0.63 and p = 0.11) or matched controls (p = 0.32 and p = 0.20). RIC improved GLS in the subgroup of patients with CIHF and with NT-proBNP plasma levels above the geometric mean of 372 ng/l (p = 0.04). RIC did not affect peak workload or oxygen uptake in either patients with CIHF (p = 0.26 and p = 0.59) or matched controls (p = 0.61 and p = 0.10). However, RIC improved skeletal muscle power in both groups (p = 0.02 for both). In patients with CIHF, RIC lowered systolic blood pressure (p < 0.01) and reduced NT-proBNP plasma levels (p = 0.02). Our findings suggest that long-term RIC treatment does not improve LVEF but increases skeletal muscle function and reduces blood pressure and NT-proBNP in patients with compensated CIHF. This should be investigated in a randomized sham-controlled trial.

Ischaemic conditioning and targeting reperfusion injury: a 30 year voyage of discovery.

To commemorate the auspicious occasion of the 30th anniversary of IPC, leading pioneers in the field of cardioprotection gathered in Barcelona in May 2016 to review and discuss the history of IPC, its evolution to IPost and RIC, myocardial reperfusion injury as a therapeutic target, and future targets and strategies for cardioprotection. This article provides an overview of the major topics discussed at this special meeting and underscores the huge importance and impact, the discovery of IPC has made in the field of cardiovascular research.

Citric Acid Cycle Metabolites Predict the Severity of Myocardial Stunning and Mortality in Newborn Pigs.

OBJECTIVES: Myocardial infarction and chronic heart failure induce specific metabolic changes in the neonatal myocardium that are closely correlated to outcome. The aim of this study was to examine the metabolic responses to noninfarct heart failure and inotropic treatments in the newborn heart, which so far are undetermined. DESIGN: A total of 28 newborn pigs were instrumented with a microdialysis catheter in the right ventricle, and intercellular citric acid cycle intermediates and adenosine metabolite concentrations were determined at 20-minute intervals. Stunning was induced by 10 cycles of 3 minutes of ischemia, which was performed by occluding the right coronary artery, followed by 3 minutes of reperfusion. Animals were randomized for treatment with epinephrine + milrinone, dopamine + milrinone, dobutamine, or saline. SETTING: University hospital animal laboratory. MAIN RESULTS: Ischemia-reperfusion induced right ventricular stunning and increased the concentrations of pyruvate lactate, succinate, malate, hypoxanthine, and xanthine (all, p < 0.01). During inotrope infusion, no differences in metabolite concentrations were detected between the treatment groups. In nonsurviving animals (n = 8), concentrations of succinate (p < 0.0001), malate (p = 0.009), and hypoxanthine (p = 0.04) increased compared with survivors, while contractility was significantly reduced (p = 0.03). CONCLUSIONS: Accumulation of citric acid cycle intermediates and adenosine metabolites reflects the presence of myocardial stunning and predicts mortality in acute noninfarct right ventricular heart failure in newborn pigs. This phenomenon occurs independently of the type of inotrope, suggesting that citric acid cycle intermediates represent potential markers of acute noninfarct heart failure.

Temporal Trend in Hospitalization Among Patients With Congenital Heart Disease: A Danish Nationwide Study.

BACKGROUND: The congenital heart disease (CHD) population is growing and aging. We aim to examine the impact by describing the temporal trend and causes of lifetime hospitalization burden among the CHD population. METHODS AND RESULTS: From the Danish National Patient Registry, 23 141 patients with CHD and their hospitalizations from 1977 to 2018 were identified, excluding patients with extracardiac malformation. Patients with CHD were categorized into major CHD and minor CHD, and each patient was matched with 10 controls by sex and year of birth. The rate of all-cause hospitalization increased over time from 28.3 to 36.4 hospitalizations per 100 person-years (PY) with rate difference (RD) per decade of 2.5 (95% CI, 2.0-3.1) hospitalizations per 100 PY for the patients with CHD, compared with the increase from 10.8 to 17.0 per 100 PY (RD per decade, 2.0 [95% CI, 1.8-2.2] per 100 PY) for the control group (RD for CHD versus control, P=0.08). The all-cause hospitalization rate remained constant for the major CHDs (RD per decade, -0.2 [95% CI, -1.2 to 0.9] per 100 PY) but increased for the minor CHDs (RD per decade, 5.2 [95% CI, 4.3-6.0] per 100 PY). For all patients with CHD, the cardiovascular hospitalization rate remained constant over time (RD per decade, 0.2 [95% CI, -0.3 to 0.6] per 100 PY) whereas the noncardiovascular hospitalization rate increased (RD per decade, 2.1 [95% CI, 1.6-2.7] per 100 PY). The length of all-cause hospital stays for all patients with CHD decreased from 2.7 (95% CI, 2.6-2.8) days per PY in 1977 to 1987 to 1.6 (95% CI, 1.6-1.7) days per PY in 2008 to 2018. CONCLUSIONS: Compared with previous decades, patients with CHD have an increasing hospitalization rate, similar to the general population, but a decreasing length of hospital stay. The increase in hospitalization rate was driven by noncardiovascular hospitalizations, with the patients with minor CHD being the key contributor to the increasing rate.

Pulmonary Valve Replacement in Tetralogy of Fallot: Procedural Volume and Durability of Bioprosthetic Pulmonary Valves.

BACKGROUND: Robust data on changes in pulmonary valve replacement (PVR) procedural volume and predictors of bioprosthetic pulmonary valve (BPV) durability in patients with tetralogy of Fallot (TOF) are scarce. OBJECTIVES: This study sought to assess temporal trends in PVR procedural volume and BPV durability in a nationwide, retrospective TOF cohort. METHODS: Data were obtained from patient records. Robust linear regression was used to assess temporal trends in PVR procedural volume. Piecewise exponential additive mixed models were used to estimate BPV durability, defined as the time from implantation to redo PVR with death as a competing risk, and to assess risk factors for reduced durability. RESULTS: In total, 546 PVR were performed in 384 patients from 1976 to 2021. The annual number of PVR increased from 0.4 to 6.0 per million population (P < 0.001). In the last decade, the transcatheter PVR volume increased by 20% annually (P < 0.001), whereas the surgical PVR volume did not change significantly. The median BPV durability was 17 years (Q1: 10-Q3: 10 years-not applicable). There was no significant difference in the durability of different BPV after adjustment for confounders. Age at PVR (HR: 0.78 per 10 years from <1 year; 95% CI: 0.63-0.96; P = 0.02) and true inner valve diameter (9-17 mm vs 18-22 mm HR: 0.40; 95% CI: 0.22-0.73; P = 0.003 and 18-22 mm vs 23-30 mm HR: 0.59; 95% CI: 0.25-1.39; P = 0.23) were associated with reduced BPV durability in multivariate models. CONCLUSIONS: The PVR procedural volume has increased over time, with a greater increment in transcatheter than surgical PVR during the last decade. Younger patient age at PVR and a smaller true inner valve diameter predicted reduced BPV durability.

Percutaneous Valvular and Structural Heart Disease Interventions.2024 Core Curriculum of the European Association of Percutaneous Cardiovascular Interventions (EAPCI) of the ESC in collaboration with the European Association of Cardiovascular Imaging (EACVI) and the Cardiovascular Surgery Working Group (WG CVS) of the European Society of Cardiology.

The percutaneous treatment of structural, valvular, and non-valvular heart disease (SHD) is rapidly evolving. The Core Curriculum (CC) proposed by the EAPCI describes the knowledge, skills, and attitudes that define competency levels required by newly trained SHD interventional cardiologists (IC) and provides guidance for training centres. SHD ICs are cardiologists who have received complete interventional cardiology training. They are multidisciplinary team specialists who manage adult SHD patients from diagnosis to follow-up and perform percutaneous procedures in this area. They are competent in interpreting advanced imaging techniques and master planning software. The SHD ICs are expected to be proficient in the aortic, mitral, and tricuspid areas. They may have selective skills in either the aortic area or mitral/tricuspid areas. In this case, they must still have common transversal competencies in the aortic, mitral, and tricuspid areas. Additional SHD domain competencies are optional. Completing dedicated SHD training, aiming for full aortic, mitral, and tricuspid competencies, requires at least 18 months. For full training in the aortic area, with basic competencies in mitral/tricuspid areas, the training can be reduced to 1 year. The same is true for training in the mitral/tricuspid area, with competencies in the aortic area. The SHD IC CC promotes excellence and homogeneous training across Europe and is the cornerstone of future certifications and patient protection. It may be a reference for future CC for national associations and other SHD specialities, including imaging and cardiac surgery.

Percutaneous Valvular and Structural Heart Disease Interventions. 2024 Core Curriculum of the European Association of Percutaneous Cardiovascular Interventions (EAPCI) of the ESC.

The percutaneous treatment of structural, valvular, and non-valvular heart disease (SHD) is rapidly evolving. The Core Curriculum (CC) proposed by the EAPCI describes the knowledge, skills, and attitudes that define competency levels required by newly trained SHD interventional cardiologists (IC) and provides guidance for training centres. SHD ICs are cardiologists who have received complete interventional cardiology training. They are multidisciplinary team specialists who manage adult SHD patients from diagnosis to follow-up and perform percutaneous procedures in this area. They are competent in interpreting advanced imaging techniques and master planning software. The SHD ICs are expected to be proficient in the aortic, mitral, and tricuspid areas. They may have selective skills in either the aortic area or mitral/tricuspid areas. In this case, they must still have common transversal competencies in the aortic, mitral, and tricuspid areas. Additional SHD domain competencies are optional. Completing dedicated SHD training, aiming for full aortic, mitral, and tricuspid competencies, requires at least 18 months. For full training in the aortic area, with basic competencies in mitral/tricuspid areas, the training can be reduced to 1 year. The same is true for training in the mitral/tricuspid area, with competencies in the aortic area. The SHD IC CC promotes excellence and homogeneous training across Europe and is the cornerstone of future certifications and patient protection. It may be a reference for future CC for national associations and other SHD specialities, including imaging and cardiac surgery.

Subarachnoid haemorrhage in a patient with undiagnosed aortic coarctation.

A man in his mid-30s was admitted with a thunderclap headache. He was conscious and hypertensive. A decade earlier, severe hypertension had been diagnosed and extensively investigated without revealing an underlying cause. Brain imaging showed subarachnoid haemorrhage caused by a ruptured pericallosal aneurysm. Endovascular occlusion was attempted, but as the sheath could not pass the aortic arch, it was converted to surgical aneurismal clipping. Intraoperative blood pressure measurement revealed a peak-to-peak gradient of 100 mm Hg across the aortic arch and an ankle/brachial index of 0.46 (normal range 0.9-1.2). Aortic coarctation was suspected, and angiographic imaging and echocardiography confirmed the diagnosis. Subacute direct stenting was performed, which normalised the peak-to-peak gradient and ankle/brachial index. To minimise the risk of severe complications, early diagnosis of aortic coarctation is important and can be facilitated by ankle/brachial index and echocardiography in the suprasternal view.

[Hybrid treatment of protein-losing enteropathy in a patient with univentricular circulation].

Protein-losing enteropathy (PLE) is a severe Fontan complication. This is a case report of the first hybrid treatment of PLE in Denmark of an 11-year-old Fontan patient with severe symptoms (diarrhoea, fatigue and swelling) and low albumin level. Diagnostics included intranodal and intrahepatic dynamic contrast magnetic resonance lymphangiography. The hybrid intervention consisted of selective lymphatic duct embolisation and innominate vein turn-down to treat PLE. The interventions went well, and two months after discharge the patient was relieved from PLE symptoms, the albumin level was normalised, and the patient felt more energetic.

Incidence of Infective Endocarditis Among Patients With Tetralogy of Fallot.

Background Patients with tetralogy of Fallot (ToF) are considered at high risk of infective endocarditis (IE) as a result of altered hemodynamics and multiple invasive procedures, including pulmonary valve replacement (PVR). Data on the long-term risk of IE are sparse. Methods and Results In this observational cohort study, all patients with ToF born from 1977 to 2018 were identified using Danish nationwide registries and followed from date of birth until occurrence of first-time IE, emigration, death, or end of study (December 31, 2018). The comparative risk of IE among patients with ToF versus age- and sex-matched controls from the background population was assessed. Because of rules on anonymity, exact numbers cannot be reported if the number of patients is <4. A total of 1164 patients with ToF were identified and matched with 4656 controls. Among patients with ToF, 851 (73.1%) underwent early surgical intracardiac repair and 276 (23.7%) underwent PVR during follow-up. During a median follow-up of 20.3 years, 41 (3.5%) patients with ToF (comprising 24 [8.7%] with PVR and 17 [1.9%] without PVR) and <4 (<0.8%) controls were admitted with IE. The incidence rates of IE per 10 000 person-years were 22.4 (95% CI, 16.5-30.4) and 0.1 (95% CI, 0.01-0.7) among patients and controls, respectively. Moreover, PVR was associated with a further increased incidence of IE among patients with ToF (incidence rates per 10 000 person-years with and without PVR were 46.7 [95% CI, 25.1-86.6] and 2.8 [95% CI 2.0-4.0], respectively). Conclusions Patients with ToF are associated with a substantially higher incidence of IE than the background population. In particular, PVR was associated with an increased incidence of IE. With an increasing life expectancy of these patients, intensified awareness, preventive measures, and surveillance of this patient group are decisive.

Transthoracic Vector Flow Imaging in Pediatric Patients with Valvular Stenosis - A Proof of Concept Study.

Purpose Continuous wave Doppler ultrasound is routinely used to detect cardiac valve stenoses. Vector flow imaging (VFI) is an angle-independent real-time ultrasound method that can quantify flow complexity. We aimed to evaluate if quantification of flow complexity could reliably assess valvular stenosis in pediatric patients. Materials and Methods Nine pediatric patients with echocardiographically confirmed valvular stenosis were included in the study. VFI and Doppler measurements were compared with transvalvular peak-to-peak pressure differences derived from invasive endovascular catheterization. Results Vector concentration correlated with the catheter measurements before intervention after exclusion of one outlier (r=-0.83, p=0.01), whereas the Doppler method did not (r=0.49, p=0.22). The change in vector concentration after intervention correlated strongly with the change in the measured catheter pressure difference (r=-0.86, p=0.003), while Doppler showed a tendency for a moderate correlation (r=0.63, p=0.07). Conclusion Transthoracic flow complexity quantification calculated from VFI data is feasible and may be useful for assessing valvular stenosis severity in pediatric patients.