Diagnosis of pulmonary hypertension associated with congenital heart disease. Part 1. Definition, classification and initial examination of patients

Having discussed current definitions and classification of pulmonary hypertension associated with congenital heart defects, the authors consider characteristic clinical symptoms and data of physical examination separately for every subgroup. An increase in pulmonary vascular resistance after radical correction and with small / concomitant defects leads to insufficient filling of the systemic ventricle and the progression of symptoms of low cardiac output , i.e. shortness of breath, palpitations, fatigue, weakness and decreased exercise tolerance. At late stages, due to transient systemic hypotension the patients feel dizziness, lightheadedness and fainting, as well as signs of congestive right ventricular failure – peripheral edema, liver enlargement, ascites and swelling of the cervical veins. The patients with Eisenmenger syndrome develop cyanosis and signs of systemic complications – polycythemia, deformation of the distal phalanges of the fingers like «drumsticks» and «watch glasses», posture disturbance due to osteoarthropathy and scoliosis, pulmonary and paradoxical systemic thrombosis and embolism, bleeding, symptoms of gout and cholelithiasis, impaired renal function. Even mild pulmonary hypertension after Fontaine’s surgery causes venous hypertension with congestive heart failure, hydrothorax, protein deficiency enteropathy and plastic bronchitis, as well as insufficient blood flow to the systemic ventricle with low cardiac output, shortness of breath, palpitations, fatigue, weakness and decreased exercise tolerance. All forms of pulmonary hypertension cause pain in the region of the heart, hemoptysis, pulmonary hemorrhage, arrhythmias, and developmental delay in children. The patient shall be examined «from head to toe.» The diagnostic value of auscultation depends on the complexity of the congenital malformation leading to pulmonary hypertension Pulse oximetry should be performed separately on the arms and legs at rest and exercise.

Myocardial Perfusion in Hypoplastic Left Heart Syndrome: Risk Factors for the Right Ventricular Microcirculation

Background: The status of the systemic right ventricular coronary microcirculation in hypoplastic left heart syndrome (HLHS) is largely unknown. It is presumed that the systemic right ventricle’s coronary microcirculation exhibits unique pathophysiological characteristics of HLHS in Fontan circulation. The present study sought to quantify myocardial blood flow by cardiac magnetic resonance imaging and evaluate the determinants of microvascular coronary dysfunction and myocardial ischemia in HLHS. Methods: One hundred nineteen HLHS patients (median age, 4.80 years) and 34 healthy volunteers (median age, 5.50 years) underwent follow-up cardiac magnetic resonance imaging ≈1.8 years after total cavopulmonary connection. Right ventricle volumes and function, myocardial perfusion, diffuse fibrosis, and late gadolinium enhancement were assessed in 4 anatomic HLHS subtypes. Myocardial blood flow (MBF) was quantified at rest and during adenosine-induced hyperemia. Coronary conductance was estimated from MBF at rest and catheter-based measurements of mean aortic pressure (n=99). Results: Hyperemic MBF in the systemic ventricle was lower in HLHS compared with controls (1.89±0.57 versus 2.70±0.84 mL/g per min; P <0.001), while MBF at rest normalized by the rate-pressure product, was similar (1.25±0.36 versus 1.19±0.33; P =0.446). Independent risk factors for a reduced hyperemic MBF were an HLHS subtype with mitral stenosis and aortic atresia ( P =0.017), late gadolinium enhancement ( P =0.042), right ventricular diastolic dysfunction ( P =0.005), and increasing age at total cavopulmonary connection ( P =0.022). The coronary conductance correlated negatively with systemic blood oxygen saturation (r, −0.29; P =0.02). The frequency of late gadolinium enhancement increased with age at total cavopulmonary connection ( P =0.014). Conclusions: The coronary microcirculation of the systemic ventricle in young HLHS patients shows significant differences compared with controls. These hypothesis-generating findings on HLHS-specific risk factors for microvascular dysfunction suggest a potential benefit from early relief of frank cyanosis by total cavopulmonary connection.

The pulmonary vascular bed in patients with functionally univentricular physiology and a Fontan circulation

Fontan palliation represents one of the most remarkable surgical advances in the management of individuals born with functionally univentricular physiology. The operation secures adult survival for all but a few with unfavourable anatomy and/or physiology. Inherent to the physiology is passive transpulmonary blood flow, which produces a vulnerability to adequate filling of the systemic ventricle at rest and during exertion. Similarly, the upstream effects of passive flow in the lungs are venous congestion and venous hypertension, especially marked during physical activity. The pulmonary vascular bed has emerged as a defining character on the stage of Fontan circulatory behaviour and clinical outcomes. Its pharmacologic regulation and anatomic rehabilitation therefore seem important strategic therapeutic targets. This review seeks to delineate the important aspects of pulmonary artery development and maturation in functionally univentricular physiology patients, pulmonary artery biology, pulmonary vascular reserve with exercise, and pulmonary artery morphologic and pharmacologic rehabilitation.

Longer sustained Fontan circulation is associated with prolonged hepatic T1 relaxation time on T1 mapping

Funding Acknowledgements Type of funding sources: None. Background Patients with single ventricle defects may develop Fontan-associated liver disease. T1 mapping has been successfully used for evaluating chronic liver disease in adults. Liver T1 mapping has been also studied in the pediatric patients with single ventricles, and these patients show higher T1 relaxation times compared to the healthy controls. Purpose Our objective was to study the relationship between the cardiac MRI (CMR) T1 mapping relaxation time of the liver and 1) CMR derived hemodynamic parameters, 2) peripheral venous pressure (PVP) measured from a cubital cannula 3) systemic ventricle morphology [LV vs. RV], 4) the age of patient, and 5) alanine transaminase (P-ALAT) levels. Methods This retrospective study included 46 patients with functional single ventricle, which underwent routine CMR at our hospital. Table 1 shows demographic and clinical data of the study population. Statistical analysis were performed with IBM SPSS Statistics v.25 software using independent samples t test, Mann-Whitney U-test or Pearson correlation as appropriate. A p-value less than 0.05 was considered significant. Results The average T1 relaxation time of the liver was longer in patients with RV morphology (p = 0.004). There was a significant moderate positive correlation between the age of the patients and hepatic T1 relaxation time (r = 0.45, p = 0.002), and between hepatic T1 relaxation time and P-ALAT levels (r = 0.5, p = 0.016) (Fig.1). No significant correlations were detected between the T1 times of the liver and hemodynamic parameters of the heart (all tested parameters are listed in the Table1). Ejection fraction and PVP showed a non-significant weak correlation with a hepatic T1 relaxation times (r=-0.3, p = 0,056 and r = 0.3, p = 0,070, respectively). Conclusions T1 mapping times of the liver may reflect Fontan-associated liver disease. We observed connections between the hepatic T1 relaxation times and 1) patients age, 2) systemic ventricle morphology and 3) P-ALAT levels.

Cardiac resynchronization therapy in paediatric patients with congenital heart disease: single centre with 10 years of experience

Objectives: In recent years, cardiac resynchronization therapy (CRT) has also started to be performed in the paediatric and CHD population. This study aimed to evaluate the efficacy of CRT in children with CHD. Patients and methods: Patients with CHD who underwent CRT treatment in our paediatric cardiology clinic between January, 2010 and January, 2020 were included in the study. Demographic findings, 12-lead electrocardiograms, echocardiograms, clinical characteristics, management strategies, and outcomes were reviewed systematically. Results: The study population consisted of 18 CHD patients who had been treated with CRT for 10 years in our institution. The median age was 11 years (2.2–18 years) and the median weight was 39 kg (10–81 kg). Systemic ventricle was left ventricle in 13 patients, right ventricle in 4 patients, and 1 patient had single-ventricle physiology. CRT implantation indications were as follows: dysfunction after permanent pacemaker in 11 patients, dysfunction after left bundle branch block in 4 patients, and systemic ventricular dysfunction in 3 patients. CRT implantation techniques were epicardial (n = 13), hybrid (n = 4), and transvenous (n = 1) methods. QRS duration significantly decreased after CRT implantation (160 versus 124 m/second, p < 0.05). Median systemic ventricle ejection fraction (EF) significantly increased after the procedure (30 versus 50%, p < 0.05). Fourteen patients (78%) were responders, two patients (11%) were superresponders, and two patients (11%) were non-responders after the CRT treatment. One patient deceased during follow-up. Median follow-up duration was 40 months (6–117 months). Conclusion: When electromechanical dyssynchrony occurs in paediatric cases with CHD and developing heart failure, patients should be evaluated in terms of CRT to improve ventricular function. Alternative CRT therapy will be beneficial in these cases that do not improve clinically despite optimal medical treatment.

Abstract 17117: Prevalence of Systemic AV Valve Regurgitation in Patients With Congenitally Corrected Transposition of the Great Arteries: Anatomic versus Physiologic Repair

Background: Congenitally corrected transposition of the great arteries (ccTGA) is a rare anomaly with highly variable time of diagnosis. Depending on time of diagnosis and associated lesions, multiple therapies exist, directed towards surgical correction. Anatomic repair (AR) involving double switch or atrial switch/Rastelli and physiologic repair (PR) leaving the right ventricle as the systemic ventricle are the two main surgical options. A subset of patients without associated lesions exist who can be followed expectantly over time. Systemic atrioventricular valve (SAVV) function is a major anatomic variable, determining eligibility for double switch and durability of physiologic repair or expectant management (medical group). We therefore sought to assess the prevalence of AV valve regurgitation in the different subgroups and its determinants, hypothesizing that SAVV regurgitation (SAVVR) was reduced in the AR group. Methods: Retrospective record review coupled with prospective cross-sectional follow-up of 240 patients with ccTGA treated at our center was performed. Echocardiographic imaging review was conducted to assess SAVV function and systemic ventricular function among the 3 subgroups. Results: Of 240 patients with ccTGA, 162 met inclusion. Median follow up was 10 years (mean +/- SD 11+/- 9 years). In the AR group majority (85%) had none/mild SAVVR. Prior PA band did not influence the severity of SAVVR following double switch. In the PR group, 22% underwent SAVV repair/replacement, and 75% had none/mild SAVVR; as opposed to only 65% with none/mild SAVVR in the medical group. Only 14% of patients were free of systemic ventricle dysfunction in PR group as opposed to 72% in the AR group. Conclusions: SAVV function is preserved in the AR group. In contrast patients in the PR group had higher prevalence of more than mild SAVVR followed by patients who were managed expectantly.

Use of echocardiographic parameters of longitudinal mechanics to estimate diastolic function of systemic ventricle in patients after fontan operation

Objective. To study the possibilities of using echocardiographic parameters of longitudinal mechanics to assess the diastolic function of the systemic ventricle (SV) in patients after Fontan operation. Material and methods. We examined 29 children aged 8,6 3,16 years with a functionally single ventricle of the heart after performing a total cavopulmonary connection with fenestration of extracardiac conduit. By computed tomography there were evaluated: myocardial mass index (MMI) SV, ejection fraction (EF) SV, cardiac output (CO) SV, cardiac index (CI) SV. In addition to conventional echocardiographic (Echo) parameters, we also studied: diastolic velocity parameters of the longitudinal mechanics of the SV during the early rapid filling phase (SR E), in the phase of late diastolic filling (SR A), the ratio of the peaks of the strain rate (SR E/SR A), the stiffness index of a functionally single atrium, the atrial strain in conduit phase (AS cd), reservoir (ASr), and in the contractile phase (AS ct). Results. Reduced values of the SI, CO and CI SV, an increase in MMI SV, normal values of EF SV. The parameters of the longitudinal diastolic strain rate in the early and late filling phases of e SV showed a direct significant correlation with SI, CO and CI SV and inverse correlation with E/e '. Parameters of longitudinal strain of the functionally single atrium in all phases were reduced, they all correlated with E / e, SR E / SR A, MMI SV, SI, CO and CI SV. There was no statistically significant relationship between the parameters of the longitudinal function of the atrium in all phases and atrial stiffness with sex and body surface area. Conclusions. 1. The parameters of the longitudinal diastolic strain rate can be used to identify the diastolic dysfunction of the systemic ventricle in children after Fontan operation. 2. The hemodynamic parameters of the systemic ventricle (stroke index, cardiac output, cardiac index) determine the parameters of its diastolic mechanics. 3. The reservoir, conduit, and contractile atrial function in patients after total cavopulmonary connection are associated with both characteristics of diastolic longitudinal strain rate and hemodynamic parameters of systemic ventricle.

The effect of a valved small conduit on systemic ventricle–pulmonary artery shunt in the Norwood-type palliation

OBJECTIVES The aim of this study was to clarify the impact of valved systemic ventricle–pulmonary artery (SV–PA) shunt on outcomes after stage-1 Norwood-type palliation (NP) compared with the modified Blalock–Taussig shunt. METHODS Consecutive patients who underwent NP between 2003 and 2019 were enrolled. SV–PA shunts using the expanded polytetrafluoroethylene valved conduit were implanted in 18 patients (valved SV–PA group), and another 18 patients underwent modified Blalock–Taussig shunt during NP (modified Blalock–Taussig shunt group). All valved conduits were made in our institution in advance. RESULTS No differences in baseline characteristics were found between the groups, except for shunt size. During a median 2.9 (interquartile range 0.4–6.4, maximum 14.2) years of follow-up, 8 (22.2%) patients died across both groups. There were no statistically significant differences in early mortality (5.5% vs 11.1%, P = 0.55) and overall survival rates at 5 years (80.8% vs 71.4%, P = 0.48) in the valved SV–PA and modified Blalock–Taussig shunt groups. No statistically significant difference was observed in the frequency of interventions between the groups (31% vs 33%, P = 1.0). At the time of the bidirectional Glenn procedure, the systemic ventricular end-diastolic volume index was significantly lower (84 ± 24 vs 106 ± 31 ml/m2, P = 0.05) and the ejection fraction was significantly greater (62 ± 8% vs 55 ± 9%, P = 0.03) in the valved SV–PA group. There was no statistically significant difference in the pulmonary artery index (228 ± 85 vs 226 ± 60 mm2/m2, P = 0.92). CONCLUSIONS A valved SV–PA shunt using an expanded polytetrafluoroethylene valved conduit was associated with preserved ventricular function after NP and did not impair pulmonary artery growth by controlling pulmonary regurgitation.

P1334 Multimodal imaging assessment of a very rare cause of heart failure in adults

Introduction Congenitally Corrected Transposition of the Great Arteries (CCTGA) is a rare defect consisting in the abnormal twisting of the heart during fetal development. As a result, the two ventricles and their valves are reversed. CCTGA is frequently associated with other cardiac abnormalities. 25% of patients are developing heart failure, related to perfusion mismatch (the morphological left ventricle is supplied by a single coronary artery), and to the progressive deterioration of the structural right ventricle situated on the systemic side of the circulation. Case report A 45-year-old male was referred to our hospital for fatigue and dyspnea, occuring in the last five months. Physical examination revealed tachypnea, a slightly intense systolic murmur at the apex, and pulmonary congestion, in the absence of cyanosis, peripheral edema or jugular venous distension. Heart rate and blood pressure were normal. Usual laboratory work-up indicated increased levels of NT-proBNP, without any other abnormalities. ECG presented signs of pressure overload of the systemic ventricle (Figure Ia). Transthoracic echocardiography (TTE) highly suggested the diagnosis of CCTGA, due to atrioventricular valve displacement, with the morphological tricuspid valve closer to the apex in 4-chamber view (Figure Ib). TTE showed also dilated and dysfunctional left ventricle, mild left atrioventricular regurgitation, and normally functional right ventricle. Cardiac computed tomography emphasized a specific feature of CCTGA: the parallel emergence of aorta and pulmonary trunk, with the aortic arch crossing over the left pulmonary artery (Figure Ic). Cardiac magnetic resonance imaging confirmed dilatation and low ejection fraction of the systemic ventricle (20%), and displayed presence of trabeculations and the moderator band in the systemic ventricle (Figure Id). None of these evaluations found additional cardiac structural anomalies. Thus, patient was diagnosed with heart failure due to isolated CCTGA. Discussions and relevance of case report. This case emphasizes a very rare cause of heart failure in adults. CCTGA is reported in 0.5-1% of all congenital diseases, especially in males. Isolated CCTGA accounts for less than 10% of all cases, and represents the phenotype that is usually diagnosed in adulthood. In the absence of associated anomalies, the prognosis of these patients is particularly affected by the occurrence of heart failure in the 4th or 5th decade of life. Meanwhile, this case highlights the importance of a multimodal approach in CCTGA, and the specific contribution of each imaging method in the process of an accurate diagnosis. Abstract P1334 Figure I