Congenitally Corrected Transposition of the Great Arteries in the Adult

ABSTRACT Introduction: Congenitally corrected transposition of the great arteries (CCTGA) is a rare anomaly. Current data available regarding adult cases is derived from small series, information simultaneously presented in pediatric publications, and one classical multicenter study. This review, not aimed to exhaust the subject, has the purpose to examine the literature addressing presentation, diagnostic methodology, and management of afflicted adult patients. Methods: A comprehensive search was undertaken in three major databases (PubMed, Cochrane, SciELO), using the keywords "congenitally corrected transposition of the great arteries" and "adults". Relevant articles in English, Spanish, and Portuguese were extracted and critically appraised in this review. Steps for study selection were: (1) identification of titles of records through databases searching, (2) removal of duplicates, (3) screening and selection of abstracts, (4) final inclusion in the study. Results: Four hundred sixty-five publications on CCTGA in adult patients were retrieved, and 166 were excluded; 299 studies were used for this review including 76 full-text articles, 70 studies related to general aspects of the subject, and, due to the small number of publications, 153 case reports. Sixty-one articles referring to combined experiences in pediatric and adult patients and judged to be relevant, but retrieved from another sources, were also included. Conclusion: Albeit clinical presentation and diagnostic criteria have been well stablished, there seems to be room for discussion related to clinical and surgical management of CCTGA in adults. Considering the rarity of the disease, well designed multicenter studies may provide answers.

Estructura y función de ventrículo derecho morfológico y enfrentado a poscarga sistémica / Structure and function of the morphological right ventricle subjected to systemic post-load

INTRODUCCIÓN: durante años se ha subestimado la relevancia de la estructura y función del ventrículo derecho. Ambos ventrículos son diferentes en morfología, ciclo de presiones, resistencias e interdependencia ventricular, por lo que no se pueden extrapolar sus comportamientos. La función ventricular derecha se deteriora por sobrecarga de presión, de volumen, o por la combinación de ambas cuando se enfrenta a la circulación sistémica. OBJETIVO: realizar una revisión actualizada de la estructura, función ventricular, terapéutica y las técnicas de imágenes de uso frecuente para la evaluación ventricular derecha. Para ello se revisaron las bases de datos Medline, PubMed, SciELO y plataforma Springerlink, disponibles desde Infomed; desde el año 2000 hasta 2015, en idioma español e inglés. DESARROLLO: se trata el origen y evolución del ventrículo derecho, su estructura, función y comportamiento de diferentes variables fisiológicas; la valoración de ventrículo derecho enfrentado a la poscarga sistémica, la presencia de muerte súbita y arritmias, así como la evaluación mediante técnicas de imagen y utilidad de la terapia de resincronización cardíaca. CONSIDERACIONES FINALES: ambos ventrículos tienen estructura y función diferentes. La disfunción de ventrículo derecho enfrentado a poscarga sistémica evoluciona en etapas progresivas. Mediante ecocardiografía transtorácica es posible estimar la función sistólica y diastólica ventricular derecha. Es preciso realizar estudios observacionales prospectivos que identifiquen herramientas ecocardiográficas útiles para estratificar a los pacientes desde la etapa subclínica, y trazar estrategias terapéuticas que preserven la función ventricular derecha.

INTRODUCTION: for many years, the relevance of the structure and the function of the right ventricle have been underestimated. Both ventricles are different in morphology, pressure cycles, resistance and ventricular interdependence, so their behaviors cannot be extrapolated. The right ventricular function deteriorates due to pressure overload, volume overload or the combination of both when subjected to the systemic circulation. OBJECTIVE: to make an updated review of the structure and function of ventricle, therapeutics and imaging techniques commonly used to evaluate the right ventricle. To this end, Medline, PubMed, SciELO databases and Springerlink platform, available from Infomed, were reviewed in English and Spanish from 2000 to 2015. DEVELOPMENT: it deals with the origin and evolution of the right ventricle, its structure, function and behavior of several physiological variables; the assessment of the right ventricle subjected to systemic post-load, the presence of sudden death and arrhythmias as well as the evaluation based on imaging techniques and the advantages of cardiac resynchronization therapy. FINAL THOUGHTS: both ventricles have different structures and functions. The dysfunction of the right ventricle subjected to systemic post-load evolves in progressive phases. By means of transthoracic echocardiography, it is possible to estimate the systolic and diastolic function of the right ventricle. It is necessary to perform prospective observational studies that would identify useful echocardiographic tools in order to stratify the patients since the subclinical phase, and then to draw up therapeutic strategies for preservation of the right ventricular function.

Athlete’s Heart with a Systemic Right Ventricle.

Objective: High load of regularly vigorous exercise leads to multiple physiological adaptations. The major cardiovascular effects are hypertrophy and dilation, predominantly of the left ventricle, and bradycardia. However, there are no reports on an athlete’s heart in a systemic right ventricle. Subject: We report on a 23 year old male endurance athlete (177cm, 69kg) with a systemic subaortic right ventricle after atrial redirection (Senning procedure) for simple transposition of the great arteries in infancy. Albeit medical doctors had imposed activity restriction to him, he has lead an active lifestyle from early childhood on, intensifying his sport activities over the years especially in cycling and running to a training volume of about 10 hours per week in winter and about 15 hours per week in summer. In 2009 he performed 1:50h on the half marathon distance. In 2013 he finished his first Marathon in 4:34h. Results: Cardiopulmonary exercise testing revealed a maximum oxygen uptake of 52.3ml/min/kg and a peak work load of 353 Watt, corresponding to 5.1Watt per kilogram body mass. Cardiovascular Magnetic Resonance showed a cardiac index of 2.9ml/min/m², a tricuspid regurgitation fraction of 4%, and a systemic right ventricle enddiastolic volume of 109ml/m² with an ejection fraction of 53%. Conclusions: With regular exercise training a systemic right ventricle can become very efficient comparable to healthy amateur athletes.

MRI for the Functional Evaluation of Systemic Right Ventricle in TGA

During the past few decades, rapid development has been achieved in cardiac MRI. Cardiac MRI has also proven to be a useful tool in congenital heart disease, especially for the evaluation of its function and physiology. MRI can measure the ventricular volume, ventricular mass, flow velocity and flow volume accurately. Cardiac MRI has basically three-dimensional natures, so it is well suited for the measurement of functional parameters of right ventricle without geometrical assumption unlike echocardiography. MRI is becoming the useful imaging modality for the evaluation of systemic right ventricle which is often failed in the patients with unoperated or surgically corrected transposition of the great arteries.