Persistent truncus arteriosus should be diagnosed early during childhood, despite the fact that cyanosis may sometimes be mild, especially in newborns, that normally have increased pulmonary resistance. It is a cyanotic heart disease and clinician's attention should be first drawn by heart failure signs: diaphoresis, poor feeding, failure to thrive and tachypnea. These gradually appear, as the pulmonary blood flow and, consequently, myocardial work increase.

Clinical examination reveals a hyperdynamic precordium, an ejection click, and a single, loud second heart sound, due to the fact that a single truncal valve exists. If this valve is insufficient, the regurgitant flow causes a murmur that is characterized as high-pitched, decrescendo and diastolic. Some studies [1] [2] find regurgitation to be an important risk factor for mortality, while others [3] [4] fail to do so. The severity of the regurgitation is, however, clinically important because, if severe, it leads to more pronounced and earlier heart failure symptoms. Auscultation is completed by a mild or intense systolic murmur along the left sternal border. A mid-diastolic mitral flow murmur can also be noted. This is because of the high pulmonary blood flow. Pulmonary over-circulation, if present, prevents severe desaturation and cyanosis.

The presentation is usually much more dramatic if patients also have an interrupted aortic arch and patent ductus arteriosus that is about to close. In this case, the clinician will diagnose cardiogenic shock.

• Congestive Heart Failure

  He had unilateral pulmonary hypertension from migration of pulmonary artery band from the main to the right pulmonary artery, severe truncal valve regurgitation from previous infective endocarditis, and progressive congestive heart failure. [ncbi.nlm.nih.gov]

  heart failure and cyanosis; the interventricular septum is usually patent. [medical-dictionary.thefreedictionary.com]

  Combined with truncal regurgitation which is present in most cases of persistent truncus arteriosus, many infants develop congestive heart failure within the neonatal period. [vhlab.umn.edu]

  However, an incompetent or insufficient truncal valve can result in regurgitation of blood back into the ventricles and subsequent congestive heart failure (CHF). [radiologykey.com]

• Cyanotic Congenital Heart Disease

  Juxtaposition of the atrial appendage is a sign of severe cyanotic congenital heart disease, and this is best diagnosed by a selective right atriogram or superior venacavogram. [ncbi.nlm.nih.gov]

  With a clinical picture of cyanotic congenital heart disease, with high pulmonary blood flow, we proceeded with the definitive tests. [nigjcardiol.org]

  Diagnosis and management of cyanotic congenital heart disease: part I. Indian J Pediatr. 2009 Jan. 76(1):57-70. [Medline]. [Guideline] Saxena A. Consensus on timing of intervention for common congenital heart disease. [emedicine.com]

• Fulminant Sepsis

  Six patients died while waiting for surgery, 1 due to extreme prematurity and the others due to fulminant sepsis, necrotizing enterocolitis and disseminated intravascular coagulation. [karger.com]

• Cyanosis

  The patient had mild cyanosis and developed heart failure soon after birth. Balloon septostomy was performed to enlarge the interatrial communication. [ncbi.nlm.nih.gov]

  Persistent truncus arteriosus should be diagnosed early during childhood, despite the fact that cyanosis may sometimes be mild, especially in newborns, that normally have increased pulmonary resistance. [symptoma.com]

  Physiologic consequences of type I include mild cyanosis, heart failure (HF), and significant pulmonary overcirculation. [checkorphan.org]

• Vascular Disease

  This case demonstrated that in patients with persistent truncus arteriosus and two pulmonary arteries, pulmonary vascular disease or underdevelopment of one lung does not preclude a full corrective surgery so long as the other vascular bed is normal. [ncbi.nlm.nih.gov]

  These findings suggested that late correction of TA should be undertaken prior to the development of pulmonary vascular disease. [cardiothoracicsurgery.biomedcentral.com]

• Single S2

  Physical examination may detect a hyperdynamic precordium, increased pulse pressure, a loud and single S2, and an ejection click. A grade 2 to 4/6 holosystolic murmur is audible along the left sternal border. [checkorphan.org]

  There is a right ventricular tap at the left sternal border, systolic ejection murmur due to RVOTO, and single S2. The VSD is usually non-restrictive and does not produce a heart murmur. [utmb.edu]

• Bounding Pulse

  Physical examination may detect a hyperdynamic precordium, increased pulse pressure with bounding pulses, a loud and single 2nd heart sound (S2), and an ejection click. [merckmanuals.com]

• Prolapse

  The cusps may prolapse, resulting in regurgitation. The truncal valve is anatomically continuous with the mitral valve but frequently not with the tricuspid valve. [radiologykey.com]

• Quadriplegia

  […] seizures (n 10), cleft palate (n 6), renal abnormalities (n 6), bilateral choanal atresia (n 3), cardiofacial syndrome (n 3), esophageal atresia (n 2), tracheoesophageal fistula (n 1), Hemophilia A (n 1), chest wall anomalies (n 1), omphalocele (n 1), quadriplegia [onlinejacc.org]

• Neonatal Seizures

  Noncardiac abnormalities Noncardiac abnormalities were described in 81 patients and included DiGeorge syndrome (n 22), dysmorphic features (n 18), neonatal seizures (n 10), cleft palate (n 6), renal abnormalities (n 6), bilateral choanal atresia (n 3) [onlinejacc.org]

Blood workup in persistent truncus arteriosus should include measurement of arterial blood gas, performed before and after a hyperoxia test if the diagnosis is uncertain. This test can also reveal acidosis if present. Electrolytes, especially total and ionized calcium should also be measured, due to the frequent association of truncus arteriosus with DiGeorge syndrome.

The thoracic radiograph shows raised pulmonary vascular markings due to pulmonary over-circulation along with cardiomegaly. A right aortic arch may coexist and be seen with this method [5]. The pulmonary arteries originate high from the common trunk.

The electrocardiogram usually shows both right and left ventricular hypertrophy. A left atrial enlargement may be present if pulmonary over-circulation is marked. Axis may slightly deviate to the right.

Echocardiography is used to establish the diagnosis. Subcostal and parasternal long axis views are key when aiming to demonstrate the single trunk arising from both ventricles and the existence of a ventricular septal defect. The trunk may override the interventricular septum in variable degrees, therefore originating more from the left or from the right ventricle. It is also important to characterize the truncal valve in terms of anatomy and function (stenosis or regurgitation) and this can be performed by doppler color imaging. The subcostal view is also used to observe the origins of the pulmonary and coronary arteries.

Prenatal echocardiography can raise disease suspicion, but differential diagnosis with similar malformations may prove difficult [6]. Four-dimensional fetal echocardiography may improve accuracy [7].

Cardiac catheterization is only used when coronary artery origin and anatomy cannot be properly characterized using echocardiography, in a preoperative setting [8].

• Right Axis Deviation

  ECG shows right axis deviation, right ventricular hypertrophy, and occasionally right atrial enlargement. [merck.com]

• Left Axis Deviation

  Cardiomegaly and increased pulmonary vascular markings on the chest x-ray film and left axis deviation with left ventricular hypertrophy on the ECG are usually present. [ncbi.nlm.nih.gov]

• Biventricular Hypertrophy

  hypertrophy Cardiomegaly Increased pulmonary vascularity Hypocalcemia (if associated with DiGeorge syndrome) The most well-known classification was the fourfold system developed by Collett and Edwards in 1949. [en.wikipedia.org]

  hypertrophy Cardiomegaly Increased pulmonary vascularity Hypocalcemia (if associated with DiGeorge syndrome ) Treatment Treatment is with neonatal surgical repair, with the objective of restoring a normal pattern of blood flow. [11] The surgery is open [ipfs.io]

  Electrocardiogram showed features of biventricular hypertrophy. Chest X-ray showed features of cardiomegaly and right aortic arch. [annals.in]

  Making the Diagnosis EKG may show biventricular hypertrophy. CXR shows increased pulmonary vascular markings and prominent ascending aorta. It may also be suggestive of right aortic arch (25% of cases). [utmb.edu]

  Biventricular hypertrophy is frequently seen. The left atrium may be dilated. A right-sided aortic arch is frequently present. Interruption of the aortic arch is occasionally present. Coronary artery anatomy can be assessed. [ejca.eg.net]

• Left Atrial Hypertrophy

  Substantial pulmonary overcirculation may produce evidence of left atrial hypertrophy. Prognosis - Persistent truncus arteriosus Not supplied. [checkorphan.org]

1. Rajasinghe H, McElhinney D, Reddy V, et al. Long-term follow-up of truncus arteriosus repaired in infancy: a twenty-year experience. J Thorac Cardiovasc Surg. 1997;113:869–879.
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3. Brown J, Ruzmetov M, Okada Y, et al. Truncus arteriosus repair : Outcomes, risk factors, reoperation and management. Eur J Cardiothorac Surg. 2001;20:221–227.
4. Kaza A, Burch P, Pinto N, et al. Durability of truncal valve repair. Ann Thorac Surg. 2010;90:1307–1312.
5. Hallermann F, Kincaid O, Tsakiris A, et al. Persistent truncus arteriosus. A radiographic and angiocardiographic study. Am J Roentgenol Radium Ther Nucl Med. 1969;107(4): 827-834.
6. Swanson T, Selamet E, Tworetzky W, et al. Truncus arteriosus: diagnostic accuracy, outcomes, and impact of prenatal diagnosis. Pediatr Cardiol. 2009;30(3):256-261.
7. Turan S, Turan OM, Desai A, et al. First-trimester fetal cardiac examination using spatiotemporal image correlation, tomographic ultrasound and color Doppler imaging for the diagnosis of complex congenital heart disease in high-risk patients. Ultrasound Obstet Gynecol. 2014;44(5):562-567.
8. Rao PS. Diagnosis and management of cyanotic congenital heart disease: part I. Indian J Pediatr. 2009;76(1):57-70.