BackgroundChronic right ventricular pacing (RVP) induces a dyssynchronous contraction pattern, producing interventricular and intraventricular asynchrony. Many studies have shown the relationship of RVP with impaired left ventricular (LV) form and function.ObjectiveThe aim of this study was to evaluate LV synchrony and function in pediatric patients receiving RVP in comparison with those receiving LV pacing (LVP).MethodsLV systolic and diastolic function and synchrony were evaluated in 80 pediatric patients with either nonsurgical or postsurgical complete atrioventricular block, with pacing from either the RV endocardium (n = 40) or the LV epicardium (n = 40). Echocardiographic data obtained before pacemaker implantation, immediately after it, and at the end of a mean follow-up of 6.8 years were analyzed.ResultsLV diastolic function did not change in any patient during follow-up. LV systolic function was preserved in patients with LVP. However, in children with RVP the shortening fraction and ejection fraction decreased from medians of 41% ± 2.6% and 70% ± 6.9% before implantation to 32% ± 4.2% and 64% ± 2.5% (p < 0.0001 and p < 0.0001), respectively, at final follow-up. Interventricular mechanical delay was significantly larger with RVP (66 ± 13 ms) than with LVP (20 ± 8 ms). Similarly, the following parameters were significantly different in the two groups: LV mechanical delay (RVP: 69 ± 6 ms, LVP: 30 ± 11 ms, p < 0.0001); septal to lateral wall motion delay (RVP: 75 ± 19 ms, LVP: 42 ± 10 ms, p < 0.0001); and, septal to posterior wall motion delay (RVP: 127 ± 33 ms, LVP: 58 ± 17 ms, p < 0.0001).ConclusionCompared with RV endocardium, LV epicardium is an optimal site for pacing to preserve cardiac synchrony and function.

Introduction: Bland, White and Garland syndrome is a coronary anomaly with high mortality without treatment. Its clinical presentation is varied which makes epidemiological documentation diffi cult. Echocardiography is a useful non-invasive tool for diagnosis. Objective: To determine the echocardiographic variables that lead to the diagnosis of Bland, White and Garland syndrome and their clinical relevance. Material: Observational, prospective and cross-sectional study in 31 patients of the "William Soler" Pediatric Cardiocenter, from 2005 to 2018. To check the association of echocardiographic variables with the diagnosis of Bland, White and Garland syndrome, an effectiveness study was carried out that included the analysis of the incidence of echocardiographic variables that lead to the diagnosis of this entity. The clinical relevance was estimated according to the minimum importance limit. The statistical validation of the research results adopted a signifi cance level of less than 5% (p < 0.05). Results: The variables that facilitate the echocardiographic diagnosis of Bland, White and Garland syndrome were the echocardiographic visualization of the anomalous connection and the reversed fl ow in the anomalous left coronary artery. These echocardiographic measures have clinical relevance according to the quantifi cation of risk estimators (incidence) the echocardiographic visualization of the anomalous connection, RR 39.00 and the reversed fl ow in the anomalous coronary artery, RR 26.31. LIM´s calculation value amounted to 6.31 and coincided with the risk estimators (incidence). Conclusion: The echocardiographic visualization of the anomalous origin of the left coronary artery from the pulmonary arterial trunk and the detection of the local intracoronary reversed fl ow instituted as factors to be considered for the effective diagnosis of the disease. The documentation of the diagnostic aspects of the syndrome through echocardiography contains high statistical value and clinical relevance.

The introduction of atrial switch operation allowed to prolong the life expectancy of those born with transposition of the great arteries. This operation involves extensive surgery in the atria and leaves the right ventricle as the systemic ventricle that develops dysfunction because its anatomy is not intended to handle systemic pressure over a lifetime. We hypothesized that certain echocardiographic variables contribute to the identifi cation of systemic right ventricular failure and accurately predict prognosis in follow-up of these patients. The objective was to desing and validate a prognostic index for the estimation of risk of systemic right ventricular failure after atrial switch operation for transposition of the great arteries. An observational, prospective, cross-sectional study was conducted in 90 patients of the Pediatric Cardio Center "William Soler" from 2011 to 2017. Early systolic dysfunction of the systemic right ventricle was observed, dependent on the increase in afterload. There are no alterations in early diastolic function. The variables that make up the prognostic index are: end-diastolic diameter and parietal thickness of the right ventricle, Right Ventricle Ejection Fraction (RVEF), Tei index, the derivative of pressure over time (dp/dt) and tricuspid regurgitation. The index shows good discriminatory capacity and adequate calibration in prediction of ventricular dysfunction. End-diastolic diameter and parietal thickness of the right ventricle, the derivative of pressure over time and tricuspid regurgitation, demonstrate clinical relevance. The prognostic index shows validity and allows its introduction into clinical practice.

ALCAPA syndrome was characterized by anomalous origin of left coronary artery from pulmonary artery. Its clinical presentation is varied and although it is an anomaly of congenital origin, it is not exclusive to pediatric ages. Its epidemiological documentation is difficult. We aimed to make the non-invasive diagnosis of the ALCAPA syndrome and its variants. An observational, prospective and cross-sectional study was conducted with 31 patients with a positive echocardiographic diagnosis of ALCAPA syndrome at Pediatric Cardio Center “William Soler” from 2005 to 2018. The variables with significance for diagnosis were the echocardiographic visualization of the anomalous connection and the reversed flow in the left coronary artery. The variables with significance for typing were age at diagnosis, ischemia in the electrocardiogram, echocardiographic visualization of left ventricle papillary muscles fibrosis, presence of severe mitral regurgitation, left ventricle spheroidal remodeling, left ventricle ejection fraction, left ventricular end-diastolic volume index, and left ventricular end-diastolic diameter index. An algorithm integrated by various diagnostic modalities associated with echocardiography as a tool for the detection of ALCAPA was developed. The documentation of the diagnostic and classificatory aspects of the syndrome is possible by detecting echocardiographic elements in conjunction with electrocardiographic and radiological aspects.