Establishing a nationwide pediatric heart transplantation program with mid-term results comparable to worldwide data - The Czech experience.

BACKGROUND: Heart transplantation (HTx) is an established therapeutic option for children with end-stage heart failure. Comprehensive pediatric nationwide HTx program was introduced in 2014 in the Czech Republic. The aim of this study was to evaluate its mid-term characteristics and outcomes and to compare them with international data. METHODS: Retrospective observational study, including all patients who underwent HTx from June 2014 till December 2022. Data from the institutional database were used for descriptive statistics and survival analyses. RESULTS: A total of 30 HTx were performed in 29 patients with congenital heart disease (CHD, N = 15, single ventricular physiology in 10 patients) and cardiomyopathy (CMP, N = 14). Ten patients were bridged to HTx by durable left ventricular assist devices (LVADs) for a mean duration of 104 (SD 89) days. There was one early and one late death during median follow-up of 3.3 (IQR 1.3-6.1) years. Survival probability at 5 years after HTx was 93%. Two patients underwent re-transplantation (one of them in an adult center). Significant rejection-free survival at 1, 3, and 6 years after HTx was 76%, 63%, and 63%, respectively. CONCLUSIONS: The introduced pediatric HTx program reflects the complexity of the treated population, with half of the patients having complex CHD and one-third being bridged to HTx by LVADs. Mid-term results are comparable to worldwide data. The data confirm the possibility of establishing a successful nationwide pediatric HTx program in a relatively small population country with well-developed pediatric cardiovascular care and other transplantation programs.

Influence of fenestration on long-term Fontan survival.

INTRODUCTION: Fenestration in the total cavopulmonary connection system may improve the outcome of patients with significant risk factors for Fontan haemodynamics. Our study aims to analyse the difference in long-term survival between non-fenestrated and fenestrated patients. METHODS: All consecutive patients (n = 351) who underwent total cavopulmonary connection between 1992 and 2016 were identified. Six early deaths were excluded resulting in a group of 345 patients. Median (interquartile range,) length of follow-up was 14.4 (7.1-19.7) years. Freedom from the composite endpoint of death, total cavopulmonary connection take-down or indication for a heart transplant was analysed. RESULTS: Fenestration was absent in 237 patients (68.7%, Group 1), was created and closed later in 79 patients (22.9%, Group 2), and remained open in 29 patients (8.4%, Group 3). Mean survival probability until composite endpoint was 97.1 and 92.9% at 10 and 20 years, respectively. Patients with patent fenestration had worse survival (p < 0.001) as compared to both the non-fenestrated and fenestration closure groups. Despite a similar outcome, exercise capacity was lower in Group 2 than 1 (p = 0.013). In 58 patients with interventional fenestration closure, Nakata index was lower at the time of closure than pre-operatively, and both the pressure in the circuit and oxygen saturation in the aorta increased significantly (p < 0.001). CONCLUSIONS: Patients with persisting risk factors preventing fenestration closure are at higher risk of reaching the composite endpoint. Patients after fenestration closure have the worse functional outcome; their survival is, however, not different from the non-fenestrated group.

Unexpected ischemia during transcatheter patent arterial duct closure.

A child undergoing routine transcatheter patent arterial duct closure developed severe transient ischemic changes in the electrocardiogram (Pardee waves) while the aortic retention skirt of the Amplatzer™ Duct Occluder was pulled against the duct orifice. The occluder was then released, and the delivery system was pulled back to inferior caval vein which led to electrocardiogram normalisation. Aortic root angiography showed a single coronary artery originating from the right sinus of Valsalva with the left coronary stem wedged behind the posterior aspect of the right ventricular outflow tract. We believe that the left coronary artery was compressed while applying tension on the occluder delivery system.

Long-Term Results of Congenital Aortic Stenosis Treatment in the Era of Percutaneous Balloon Valvuloplasty: Up to 33 Years Follow-Up.

Background The goal of this study was to evaluate long-term results of percutaneous balloon valvuloplasty (BVPL) used exclusively for initial management of congenital aortic stenosis in children. Methods and Results A total of 409 consecutive pediatric patients (134 newborns, 275 older patients) who underwent BVPL as initial treatment of aortic stenosis in a single nationwide pediatric center were subjected to a retrospective follow-up study. The resulting follow-up time reached a median of 18.5 (interquartile range, 12.2-25.1) years. Successful BVPL was defined by residual Doppler gradient <70/40 (systolic/mean) mm Hg. The primary end point was death; secondary end points included any valve reintervention, balloon revalvuloplasty, any aortic valve surgery, and aortic valve replacement, respectively. BVPL effectively reduced the peak and mean gradient both immediately and at the latest follow-up (P<0.001). There was significant procedure-related progression of aortic insufficiency (P<0.001). Higher aortic annulus z score was predictive for severe aortic regurgitation (P<0.05) and lower z score for insufficient gradient reduction (P<0.05). The actuarial probability of survival/survival free from any valve reintervention was 89.9%/59.9%, 85.9%/35.2%, and 82.0%/26.7% at 10, 20, and 30 years after first BVPL, respectively. Left ventricular dysfunction or arterial duct dependency as the indication for BVPL was predictive of both worse survival and survival free from any reintervention (P<0.001). Lower aortic annulus z score and lower balloon-to-annulus ratio were predictive of a need for revalvuloplasty (P<0.001). Conclusions Percutaneous BVPL provides good initial palliation. In patients with hypoplastic annuli and left ventricular or mitral valve comorbidity, the results are less favorable.

Permanent epicardial pacing in children: long-term results and factors modifying outcome.

AIMS: To evaluate the results of permanent epicardial pacing in children. METHODS AND RESULTS: All consecutive patients from one country (n = 119, period 1977-2009) undergoing permanent epicardial pacemaker implantation at <18 years of age (median 1.8 years, inter-quartile range 0.3-6.4 years) were studied retrospectively. Median patient follow up was 6.4 years (inter-quartile range 2.9-11.1 years); 207 generators, 89 atrial and 153 ventricular pacing leads were implanted. The probability of absence of any pacing system dysfunction was 70.1 and 47.2% at 5 and 10 years after implantation, respectively. Overall probability of continued epicardial pacing was 92.8 and 76.1% at 5 and 10 years, respectively, and increased in the recent implantation era (post-2000, P = 0.04). The use of steroid-eluting leads decreased the risk of exit block with a hazard ratio (HR) of 0.20 [95% confidence interval (CI) 0.09-0.44, P < 0.001)]. The use of bipolar Medtronic 4968 leads reduced the risk of surgical reintervention because of fracture, insulation break, outgrowth or exit block in comparison to the unipolar 4965 lead design (HR 0.12, 95% CI 0.04-0.40, P < 0.001). The AutoCapture™ feature (HR 0.08, 95% CI 0.02-0.36, P < 0.001) and steroid-eluting leads (HR 0.30, 95% CI 0.11-0.84, P = 0.021) decreased the risk of battery depletion. CONCLUSION: The probability of continued epicardial pacing in children was 76% at 10 years after implantation, increased for implantation in recent years, and allowed transvenous pacing to be deferred to a significantly greater age. The use of bipolar steroid-eluting leads and of a beat-to-beat capture tracking feature significantly increased pacing system longevity and decreased the need for surgical reinterventions.

Exercise capacity after total cavopulmonary anastomosis: a longitudinal paediatric and adult study.

AIMS: Fontan palliation is a surgical strategy for patients with complex congenital heart disease, in whom biventricular circulation cannot be achieved. Long-term survival is negatively affected by the absence of sub-pulmonary ventricle and increased systemic venous pressure. Exercise capacity is a known predictor of overall survival and quality of life in congenital heart defects. We aim to track individual trends of peak oxygen uptake (V̇O2 peak) after total cavopulmonary connection (TCPC), identify predictors of deterioration, and derive a disease-specific reference V̇O2 peak dataset. METHODS AND RESULTS: A retrospective study of serial cardiopulmonary exercise testing (CPET) data, gathered from all patients who underwent TCPC in the Czech Republic between 1992 and 2016. Of 354 consecutive patients with TCPC, 288 (81.4%) patients underwent one or more CPETs yielding 786 unique V̇O2 peak values used as a reference dataset. Longitudinal data were available in 206 (58.2%) patients, who underwent a median (inter-quartile range) of 3.0 (2.0-5.0) CPETs over a mean (standard deviation) of 8.9 (5.5) years. The decline of exercise capacity with age was linear and not faster than in healthy peers (P = 0.47), but relative values of V̇O2 peak in TCPC patients were 12.6 mL/min/kg lower. Single ventricular morphology and pulmonary artery size had no significant influence on the exercise capacity dynamics. V̇O2 peak decline correlated negatively with the trend of body mass index z-score (P = 0.006) and was faster in women than men (P = 0.008). CONCLUSIONS: Total cavopulmonary connection patients have significantly reduced exercise capacity. The age-related decline paralleled the healthy population and correlated negatively with the body mass index trend. The presented V̇O2 peak reference dataset may help the clinicians to grade the severity of exercise capacity impairment in individual TCPC patients.

Impact of liver fibrosis and nodules formation on hemodynamics in young adults after total cavopulmonary connection. A magnetic resonance study.

Background: The aim of this study was to analyze the relation between the hepatic fibrosis markers, liver morphology and hemodynamics assessed by magnetic resonance imaging (MRI) after total cavopulmonary connection (TCPC). Materials and methods: Adult patients after TCPC performed in childhood between 1993 and 2003 are the subjects of this observational study. The follow-up protocol consisted of clinical and echocardiographic examination, liver elastography, cardiopulmonary exercise test, MRI hemodynamics and liver morphology assessment and direct enhanced liver fibrosis (ELF) test. Results: The cohort consisted of 39 patients (46% female) with a median age at study 26 (IQR 23-28) years and interval from TCPC 21 (IQR 20-23) years. There was no correlation between ELF test and any MRI variables, but procollagen III amino-terminal peptide (PIIINP), a single component of ELF test, correlated significantly with ventricular end-diastolic volume (r = 0.33; p = 0.042) and inferior vena cava flow (r = 0.47; p = 0.003). Fifteen (38%) patients with liver nodules had compared to other 24 patients higher end-diastolic volume (ml/m2) 102.8 ± 20.0 vs. 88.2 ± 17.7; p = 0.023, respectively. PIIINP correlated significantly with inferior vena cava flow (r = 0.56; p = 0.030) and with end-diastolic volume (r = 0.53; p = 0.043), but only in patients with liver nodules. Conclusion: Gradual progression of liver fibrosis, particularly hepatic arterialization caused by liver nodules formation, increases inferior vena cava flow and subsequent ventricular volume overload may further compromise single ventricle functional reserve in adult patients after TCPC.

Spectrum of postmortem autopsy findings in native and surgically corrected hearts with congenital malformations: a 10-year single-center experience.

OBJECTIVES: We reviewed a spectrum of congenital heart defects assessed in our center between 1/2010 and 4/2020, evaluated their gross anatomy, assessed the age distribution, evaluated performed surgical procedures, and correlated gross and ultrasound findings. METHODS: All necroptic cases and explanted hearts that underwent specialized cardiac autopsy were included in this study. Autopsy findings including gross description of congenital heart defects together with echocardiographic findings were retrospectively assessed. In surgically corrected hearts, the operation records were included as well. All congenital heart defects and surgical procedures were subclassified into main and additional category. RESULTS: The study included 92 necroptic cases of live-born children, 7 stillbirths, 2 cases of young adults, 50 induced abortions, and 5 explanted hearts, with median age 36 weeks. The most frequently encountered leading congenital heart defects were hypoplastic left heart syndrome, aortic stenosis, septal defects, or persistent arterial trunk. Fifty-one patients underwent surgical repair represented mainly by valvuloplasties, aortoplasty, and procedures leading to univentricular circulation. In the native hearts, 4 postnatal and 16 abortion/stillbirth cases showed discordance between gross and sonographic findings, mainly attributed to missed ventricular septal defect. Gestational age of the discordant group was significantly lower compared to the concordant group (P= .007). CONCLUSIONS: Autopsy continues to provide essential information about the morphology of congenital heart defects. However, the encountered congenital heart defects were usually complex, often surgically corrected or evaluated as a result of induced abortion or still birth. Cardiac autopsy therefore places high demands on pathologists with regards to proper gross heart assessment. It is also an invaluable part of quality control in prenatal cardiology.

Electrophysiologic profile and results of invasive risk stratification in asymptomatic children and adolescents with the Wolff-Parkinson-White electrocardiographic pattern.

BACKGROUND: Data on the results and clinical effect of an invasive risk stratification strategy in asymptomatic young patients with the Wolff-Parkinson-White electrocardiographic pattern are scarce. METHODS AND RESULTS: Eighty-five consecutive patients aged<18 years with a Wolff-Parkinson-White pattern and persistent preexcitation at maximum exercise undergoing invasive risk stratification were retrospectively studied. Adverse accessory pathway (AP) properties were defined according to currently consented criteria as any of the following: shortest preexcited RR interval during atrial fibrillation/rapid atrial pacing≤250 ms (or antegrade effective refractory period≤250 ms if shortest preexcited RR interval was not available) or inducible atrioventricular re-entrant tachycardia. Age at evaluation was median 14.9 years. Eighty-two patients had a structurally normal heart and 3 had hypertrophic cardiomyopathy. A single manifest AP was present in 80, 1 manifest and 1 concealed AP in 4, and 2 manifest APs in 1 patient. Adverse AP properties were present in 32 of 85 patients (37.6%) at baseline and in additional 16 of 44 (36.4%) after isoproterenol. Ablation was performed in 41 of these 48 patients. Ablation was deferred in the remaining 7 for pathway proximity to the atrioventricular node. In addition, 18 of the low-risk patients were ablated based on patient/parental decision. CONCLUSIONS: Adverse AP properties at baseline were exhibited by 37.6% of the evaluated patients with an asymptomatic Wolff-Parkinson-White preexcitation persisting at peak exercise. Isoproterenol challenge yielded additional 36.4% of those tested at higher risk. Ablation was performed in a total of 69.4% of patients subjected to invasive risk stratification.