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Transposition of the Great Vessels

Transposition of the great vessels (TGV) is a cyanotic congenital Congenital Chorioretinitis heart disease characterized by “switching” of the great arteries Arteries Arteries are tubular collections of cells that transport oxygenated blood and nutrients from the heart to the tissues of the body. The blood passes through the arteries in order of decreasing luminal diameter, starting in the largest artery (the aorta) and ending in the small arterioles. Arteries are classified into 3 types: large elastic arteries, medium muscular arteries, and small arteries and arterioles. Arteries: Histology. There are 2 presentations: the dextro (D)- and levo (L)-looped forms. The L-looped form is rare and congenitally corrected, as the ventricles are also switched. The D-looped form accounts for 3% of all cases of congenital Congenital Chorioretinitis heart disease. The condition occurs within the neonatal phase of life with cyanosis Cyanosis A bluish or purplish discoloration of the skin and mucous membranes due to an increase in the amount of deoxygenated hemoglobin in the blood or a structural defect in the hemoglobin molecule. Pulmonary Examination that is unresponsive to oxygen therapy. Diagnosis is confirmed by echocardiogram and a chest X-ray X-ray Penetrating electromagnetic radiation emitted when the inner orbital electrons of an atom are excited and release radiant energy. X-ray wavelengths range from 1 pm to 10 nm. Hard x-rays are the higher energy, shorter wavelength x-rays. Soft x-rays or grenz rays are less energetic and longer in wavelength. The short wavelength end of the x-ray spectrum overlaps the gamma rays wavelength range. The distinction between gamma rays and x-rays is based on their radiation source. Pulmonary Function Tests showing the classic “egg on a string” pattern. Treatment is primarily surgical, and the prognosis Prognosis A prediction of the probable outcome of a disease based on a individual's condition and the usual course of the disease as seen in similar situations. Non-Hodgkin Lymphomas for surgically corrected cases is good.

Last updated: 24 Mar, 2022

Editorial responsibility: Stanley Oiseth, Lindsay Jones, Evelin Maza

Overview

Definition

Transposition of the great vessels (TGV) is the switching of the origins of the great vessels whereby the aorta Aorta The main trunk of the systemic arteries. Mediastinum and Great Vessels: Anatomy arises from the right ventricle and the pulmonary artery Pulmonary artery The short wide vessel arising from the conus arteriosus of the right ventricle and conveying unaerated blood to the lungs. Lungs: Anatomy arises from the left ventricle.

Epidemiology

  • 3% of all cases of congenital Congenital Chorioretinitis heart disease and 20% of cyanotic congenital Congenital Chorioretinitis heart disease
  • Prevalence Prevalence The total number of cases of a given disease in a specified population at a designated time. It is differentiated from incidence, which refers to the number of new cases in the population at a given time. Measures of Disease Frequency: approximately 4 in 10,000 live births
  • Associated cardiac Cardiac Total Anomalous Pulmonary Venous Return (TAPVR) anomalies:
    • Ventricular septal defect Ventricular Septal Defect Tetralogy of Fallot (VSD): in 50% of cases
    • Left ventricle outflow tract obstruction: 
    • Coronary arteries Arteries Arteries are tubular collections of cells that transport oxygenated blood and nutrients from the heart to the tissues of the body. The blood passes through the arteries in order of decreasing luminal diameter, starting in the largest artery (the aorta) and ending in the small arterioles. Arteries are classified into 3 types: large elastic arteries, medium muscular arteries, and small arteries and arterioles. Arteries: Histology: variable Variable Variables represent information about something that can change. The design of the measurement scales, or of the methods for obtaining information, will determine the data gathered and the characteristics of that data. As a result, a variable can be qualitative or quantitative, and may be further classified into subgroups. Types of Variables origins and short course
    • Mitral or tricuspid valve Tricuspid valve The valve consisting of three cusps situated between the right atrium and right ventricle of the heart. Heart: Anatomy abnormalities

Etiology

  • Not completely delineated
  • Attributed to:
    •  Failed growth of the subpulmonary conus 
    •  Failure of absorption Absorption Absorption involves the uptake of nutrient molecules and their transfer from the lumen of the GI tract across the enterocytes and into the interstitial space, where they can be taken up in the venous or lymphatic circulation. Digestion and Absorption at the subaortic conus
  • Increased risk in diabetic mothers
  • No strong genetic component, may be seen in some cases of DiGeorge syndrome DiGeorge syndrome DiGeorge syndrome (DGS) is a condition caused by a microdeletion at location q11.2 of chromosome 22 (thus also called 22q11.2 syndrome). There is a defective development of the third and fourth pharyngeal pouches, leading to thymic and parathyroid hypoplasia (causing T-cell immunodeficiency and hypocalcemia, respectively). DiGeorge Syndrome

Pathophysiology and Clinical Presentation

Pathophysiology

  • 2 parallel circuits:
  • Tolerated well in utero:
  • After birth, complete separation of the circuits is not compatible with life.
  • Viability depends on the intercirculatory mixing of blood:
    • Intracardiac Intracardiac Total Anomalous Pulmonary Venous Return (TAPVR)
      • Patent foramen ovale Patent Foramen Ovale A patent foramen ovale (PFO) is an abnormal communication between the atria that persists after birth. The condition results from incomplete closure of the foramen ovale. Small, isolated, and asymptomatic PFOs are a common incidental finding on echocardiography and require no treatment. Patent Foramen Ovale ( PFO PFO A patent foramen ovale (PFO) is an abnormal communication between the atria that persists after birth. The condition results from incomplete closure of the foramen ovale. Small, isolated, and asymptomatic pfos are a common incidental finding on echocardiography and require no treatment. Patent Foramen Ovale)
      • Atrial septal defect Atrial Septal Defect Atrial septal defects (ASDs) are benign acyanotic congenital heart defects characterized by an opening in the interatrial septum that causes blood to flow from the left atrium (LA) to the right atrium (RA) (left-to-right shunt). Atrial Septal Defect (ASD) ( ASD ASD Autism spectrum disorder (ASD) is a neurodevelopmental disorder marked by poor social skills, restricted interests/social interactions, and repetitive/stereotyped behaviors. The condition is termed a “spectrum” because of the wide variability in the severity of symptoms exhibited. Autism Spectrum Disorder)
      • VSD
    • Extracardiac: patent ductus arteriosus Patent ductus arteriosus The ductus arteriosus (DA) allows blood to bypass pulmonary circulation. After birth, the DA remains open for up to 72 hours and then constricts and involutes, becoming the ligamentum arteriosum. Failure of this process to occur results in patent ductus arteriosus (PDA), a condition that causes up to 10% of congenital heart defects. Patent Ductus Arteriosus (PDA) ( PDA PDA The ductus arteriosus (DA) allows blood to bypass pulmonary circulation. After birth, the DA remains open for up to 72 hours and then constricts and involutes, becoming the ligamentum arteriosum. Failure of this process to occur results in patent ductus arteriosus (PDA), a condition that causes up to 10% of congenital heart defects. Patent Ductus Arteriosus (PDA))
  • Mixing of blood: 
  • Preferential shunting in 1 direction → clinical deterioration:
    • Worsening hypoxemia Hypoxemia Neonatal Respiratory Distress Syndrome/ cyanosis Cyanosis A bluish or purplish discoloration of the skin and mucous membranes due to an increase in the amount of deoxygenated hemoglobin in the blood or a structural defect in the hemoglobin molecule. Pulmonary Examination
    • Heart failure Heart Failure A heterogeneous condition in which the heart is unable to pump out sufficient blood to meet the metabolic need of the body. Heart failure can be caused by structural defects, functional abnormalities (ventricular dysfunction), or a sudden overload beyond its capacity. Chronic heart failure is more common than acute heart failure which results from sudden insult to cardiac function, such as myocardial infarction. Total Anomalous Pulmonary Venous Return (TAPVR)
Transposition of the great vessels compared to normal heart

A normal heart versus the heart of a patient with TGV
The origin of the aorta Aorta The main trunk of the systemic arteries. Mediastinum and Great Vessels: Anatomy is from the right ventricle, which carries deoxygenated blood, while the pulmonary artery Pulmonary artery The short wide vessel arising from the conus arteriosus of the right ventricle and conveying unaerated blood to the lungs. Lungs: Anatomy originates from the left ventricle.

Image by Lecturio.

Clinical presentation Presentation The position or orientation of the fetus at near term or during obstetric labor, determined by its relation to the spine of the mother and the birth canal. The normal position is a vertical, cephalic presentation with the fetal vertex flexed on the neck. Normal and Abnormal Labor

  • Apparent in the neonatal phase (1st 30 days of life)
  • Cyanosis Cyanosis A bluish or purplish discoloration of the skin and mucous membranes due to an increase in the amount of deoxygenated hemoglobin in the blood or a structural defect in the hemoglobin molecule. Pulmonary Examination:
    • Severe, with intact ventricular septum
    • Mild, with ASD ASD Autism spectrum disorder (ASD) is a neurodevelopmental disorder marked by poor social skills, restricted interests/social interactions, and repetitive/stereotyped behaviors. The condition is termed a “spectrum” because of the wide variability in the severity of symptoms exhibited. Autism Spectrum Disorder, PFO PFO A patent foramen ovale (PFO) is an abnormal communication between the atria that persists after birth. The condition results from incomplete closure of the foramen ovale. Small, isolated, and asymptomatic pfos are a common incidental finding on echocardiography and require no treatment. Patent Foramen Ovale, or large VSD Large VSD Ventricular Septal Defect (VSD)
    • Not responsive to supplemental oxygen Supplemental Oxygen Respiratory Failure
    • Not affected by feeding/crying
    • Reverse differential cyanosis Cyanosis A bluish or purplish discoloration of the skin and mucous membranes due to an increase in the amount of deoxygenated hemoglobin in the blood or a structural defect in the hemoglobin molecule. Pulmonary Examination:
      • Higher post-ductal than pre-ductal saturations
      • If aortic coarctation, interrupted aortic arch Aortic arch Mediastinum and Great Vessels: Anatomy, or pulmonary hypertension Pulmonary Hypertension Pulmonary hypertension (PH) or pulmonary arterial hypertension (PAH) is characterized by elevated pulmonary arterial pressure, which can lead to chronic progressive right heart failure. Pulmonary hypertension is grouped into 5 categories based on etiology, which include primary PAH, and PH due to cardiac disease, lung or hypoxic disease, chronic thromboembolic disease, and multifactorial or unclear etiologies. Pulmonary Hypertension are also present with TGV
  • Tachypnea Tachypnea Increased respiratory rate. Pulmonary Examination
  • Heart failure Heart Failure A heterogeneous condition in which the heart is unable to pump out sufficient blood to meet the metabolic need of the body. Heart failure can be caused by structural defects, functional abnormalities (ventricular dysfunction), or a sudden overload beyond its capacity. Chronic heart failure is more common than acute heart failure which results from sudden insult to cardiac function, such as myocardial infarction. Total Anomalous Pulmonary Venous Return (TAPVR):

Diagnosis

Physical examination

  • Visible cyanosis Cyanosis A bluish or purplish discoloration of the skin and mucous membranes due to an increase in the amount of deoxygenated hemoglobin in the blood or a structural defect in the hemoglobin molecule. Pulmonary Examination 
  • Respiratory rate Respiratory rate The number of times an organism breathes with the lungs (respiration) per unit time, usually per minute. Pulmonary Examination > 60/min
  • Failed pulse oximetry screening Screening Preoperative Care test
  • Murmurs:
    • Pansystolic murmur of VSD 
    • Systolic ejection murmur if left ventricular outlet obstruction is present
  • Diminished femoral pulses: if there is also aortic coarctation or arch interruption

Imaging

  • Echocardiogram:
    • Prenatal: not always diagnostic
    • Postnatal echocardiogram is a main confirmatory test:
      • Evaluate the degree of atrial mixing.
      • VSD
      • Valve abnormalities
      • PDA PDA The ductus arteriosus (DA) allows blood to bypass pulmonary circulation. After birth, the DA remains open for up to 72 hours and then constricts and involutes, becoming the ligamentum arteriosum. Failure of this process to occur results in patent ductus arteriosus (PDA), a condition that causes up to 10% of congenital heart defects. Patent Ductus Arteriosus (PDA)
      • Coronary artery Coronary Artery Truncus Arteriosus anatomy
  • Chest X ray: classic “egg on a string” appearance

Other tests

  • Electrocardiogram Electrocardiogram An electrocardiogram (ECG) is a graphic representation of the electrical activity of the heart plotted against time. Adhesive electrodes are affixed to the skin surface allowing measurement of cardiac impulses from many angles. The ECG provides 3-dimensional information about the conduction system of the heart, the myocardium, and other cardiac structures. Electrocardiogram (ECG):
  • Cardiac Cardiac Total Anomalous Pulmonary Venous Return (TAPVR) catheterization (angiogram):
    • Can help assess origins/anatomy of coronary arteries Arteries Arteries are tubular collections of cells that transport oxygenated blood and nutrients from the heart to the tissues of the body. The blood passes through the arteries in order of decreasing luminal diameter, starting in the largest artery (the aorta) and ending in the small arterioles. Arteries are classified into 3 types: large elastic arteries, medium muscular arteries, and small arteries and arterioles. Arteries: Histology prior to surgery
    • Can be therapeutic: balloon atrial septostomy Atrial Septostomy Tricuspid Valve Atresia (TVA) to increase blood mixing

Management and Prognosis

Management

Medical:

Surgery:

Prognosis Prognosis A prediction of the probable outcome of a disease based on a individual’s condition and the usual course of the disease as seen in similar situations. Non-Hodgkin Lymphomas

  • If not treated: 
    • 90% of patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship will die within the 1st year.
    • 30% of patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship will die within the 1st week.
  • If treated, high morbidity Morbidity The proportion of patients with a particular disease during a given year per given unit of population. Measures of Health Status with continuous follow-up and decreased exercise capacity
  • Higher chance of neurodevelopmental delay in infants

Differential Diagnosis

  • Tetralogy of Fallot Tetralogy of Fallot Tetralogy of Fallot is the most common cyanotic congenital heart disease. The disease is the confluence of 4 pathologic cardiac features: overriding aorta, ventricular septal defect, right ventricular outflow obstruction, and right ventricular hypertrophy. Tetralogy of Fallot: a congenital Congenital Chorioretinitis heart disease characterized by the occurrence of 4 key cardinal  features: overriding aorta Overriding Aorta Tetralogy of Fallot, VSD, RVOT obstruction, and right ventricular hypertrophy Right Ventricular Hypertrophy Tetralogy of Fallot. Patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship present with cyanosis Cyanosis A bluish or purplish discoloration of the skin and mucous membranes due to an increase in the amount of deoxygenated hemoglobin in the blood or a structural defect in the hemoglobin molecule. Pulmonary Examination and a history of tet spells Tet Spells Tetralogy of Fallot. Diagnosis is confirmed by an echocardiogram and patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship are surgically managed.
  • Tricuspid atresia Atresia Hypoplastic Left Heart Syndrome (HLHS): congenital Congenital Chorioretinitis heart disease characterized by the lack of development of the tricuspid valve Tricuspid valve The valve consisting of three cusps situated between the right atrium and right ventricle of the heart. Heart: Anatomy. Presents with cyanosis Cyanosis A bluish or purplish discoloration of the skin and mucous membranes due to an increase in the amount of deoxygenated hemoglobin in the blood or a structural defect in the hemoglobin molecule. Pulmonary Examination, labored breathing, and hypoxic spells. Holosystolic murmur Holosystolic Murmur Tricuspid Valve Atresia (TVA) and single S2 S2 Heart Sounds are present on exam. Diagnosis is made by echocardiogram and ECG ECG An electrocardiogram (ECG) is a graphic representation of the electrical activity of the heart plotted against time. Adhesive electrodes are affixed to the skin surface allowing measurement of cardiac impulses from many angles. The ECG provides 3-dimensional information about the conduction system of the heart, the myocardium, and other cardiac structures. Electrocardiogram (ECG).
  • Truncus arteriosus Truncus arteriosus Truncus arteriosus (TA) is a congenital heart defect characterized by the persistence of a common cardiac arterial trunk tract that fails to divide into the pulmonary artery and aorta during embryonic development. Truncus arteriosus is a rare congenital malformation with a high mortality rate within the 1st 5 weeks of life if not managed promptly. Truncus Arteriosus: emergence of aorta Aorta The main trunk of the systemic arteries. Mediastinum and Great Vessels: Anatomy and pulmonary artery Pulmonary artery The short wide vessel arising from the conus arteriosus of the right ventricle and conveying unaerated blood to the lungs. Lungs: Anatomy from a common trunk overriding a VSD. Symptomatic from the 1st days of life, including cyanosis Cyanosis A bluish or purplish discoloration of the skin and mucous membranes due to an increase in the amount of deoxygenated hemoglobin in the blood or a structural defect in the hemoglobin molecule. Pulmonary Examination, respiratory distress, heart failure Heart Failure A heterogeneous condition in which the heart is unable to pump out sufficient blood to meet the metabolic need of the body. Heart failure can be caused by structural defects, functional abnormalities (ventricular dysfunction), or a sudden overload beyond its capacity. Chronic heart failure is more common than acute heart failure which results from sudden insult to cardiac function, such as myocardial infarction. Total Anomalous Pulmonary Venous Return (TAPVR), poor feeding, and excessive sweating. Diagnosed by echocardiogram.
  • Total anomalous pulmonary venous return: rare congenital Congenital Chorioretinitis cardiopathy in which pulmonary veins Veins Veins are tubular collections of cells, which transport deoxygenated blood and waste from the capillary beds back to the heart. Veins are classified into 3 types: small veins/venules, medium veins, and large veins. Each type contains 3 primary layers: tunica intima, tunica media, and tunica adventitia. Veins: Histology drain to sites other than the left atrium. Presents with cyanosis Cyanosis A bluish or purplish discoloration of the skin and mucous membranes due to an increase in the amount of deoxygenated hemoglobin in the blood or a structural defect in the hemoglobin molecule. Pulmonary Examination from birth, heart failure Heart Failure A heterogeneous condition in which the heart is unable to pump out sufficient blood to meet the metabolic need of the body. Heart failure can be caused by structural defects, functional abnormalities (ventricular dysfunction), or a sudden overload beyond its capacity. Chronic heart failure is more common than acute heart failure which results from sudden insult to cardiac function, such as myocardial infarction. Total Anomalous Pulmonary Venous Return (TAPVR), and respiratory distress. Characterized by wide-split S2 S2 Heart Sounds.
  • Ebstein anomaly: congenital Congenital Chorioretinitis heart defect in which there is downward displacement Displacement The process by which an emotional or behavioral response that is appropriate for one situation appears in another situation for which it is inappropriate. Defense Mechanisms of the tricuspid valve Tricuspid valve The valve consisting of three cusps situated between the right atrium and right ventricle of the heart. Heart: Anatomy leaflets causing RVOT obstruction. Presents with cyanosis Cyanosis A bluish or purplish discoloration of the skin and mucous membranes due to an increase in the amount of deoxygenated hemoglobin in the blood or a structural defect in the hemoglobin molecule. Pulmonary Examination, arrhythmias, and failure to thrive Failure to Thrive Failure to thrive (FTT), or faltering growth, describes suboptimal weight gain and growth in children. The majority of cases are due to inadequate caloric intake; however, genetic, infectious, and oncological etiologies are also common. Failure to Thrive. Diagnosed by echocardiogram.

References

  1. Fillipps, D.J., M.D., & Bucciarelli, R. L., M.D. (2015). Cardiac evaluation of the newborn. Pediatric Clinics of North America, 62(2), 471-489. doi:http://dx.doi.org/10.1016/j.pcl.2014.11.009
  2. Fulton D.R., Kane D.A. (2020). Pathophysiology, clinical manifestations, and diagnosis of D-transposition of the great arteries. Retrieved December 22, 2020, from https://www.uptodate.com/contents/pathophysiology-clinical-manifestations-and-diagnosis-of-d-transposition-of-the-great-arteries?search=transposition%20of%20great%20vessels&source=search_result&selectedTitle=1~63&usage_type=default&display_rank=1
  3. Fulton D.R., Kane D.A. (2019). Management and outcome of D-transposition of the great arteries. Retrieved December 22, 2020, from https://www.uptodate.com/contents/management-and-outcome-of-d-transposition-of-the-great-arteries?search=transposition%20of%20great%20vessels&source=search_result&selectedTitle=2~63&usage_type=default&display_rank=2 
  4. Kliegman, R.M., M.D., St Geme, Joseph W., M.D., Blum, N. J., M.D., Shah, Samir S., M.D., M.S.C.E., Tasker, Robert C., M.B.B.S., M.D., & Wilson, Karen M., M.D., M.P.H. (2020). Cyanotic congenital heart disease: Lesions associated with decreased pulmonary blood flow. In R.M. Kliegman M.D. et al., Nelson textbook of pediatrics (pp. 239-2407.e1). https://www.clinicalkey.es/#!/content/3-s2.0-B9780323529501004570
  5. Scholz, T., & Reinking, B. E. (2019). Cardiopatías congénitas. In C. A. Gleason MD, & Juul, Sandra E., M.D., Ph.D. (Eds.), Avery. Enfermedades del Recién Nacido (pp. 801-827). https://www.clinicalkey.es/#!/content/3-s2.0-B9788491133889000556

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