Congenital Cardiac Anesthesia Society
A Section of the the Society for Pediatric Anesthesia

{“questions”:{“buizk”:{“id”:”buizk”,”mediaType”:”image”,”answerType”:”text”,”imageCredit”:””,”image”:””,”imageId”:””,”video”:””,”imagePlaceholder”:””,”imagePlaceholderId”:””,”title”:”Author: Sana Ullah, MB ChB, FRCA \u2013 Dallas, TX \r\n\r\nAn 8-month-old male infant is status post repair of a large perimembranous ventricular septal defect (VSD). After separation from cardiopulmonary bypass, the patient has the following vital signs: heart rate 130, blood pressure 80\/45, and pulse oximetry 99% with a fractional inspired oxygen (FiO_{2<\/sub>) of 0.25. The post-repair transesophageal echocardiogram (TEE) reveals a small residual VSD. In order to determine if the VSD is hemodynamically significant, the surgeon samples blood from the superior vena cava (SVC) and the main pulmonary artery (PA), resulting in oxygen saturations of 60% and 80% respectively. What is the Qp:Qs?”,”desc”:”EXPLANATION \r\nSmall residual ventricular septal defects (VSDs) are common after surgical repair and the decision to return to bypass is sometimes be difficult. The decision is based on TEE findings, direct pressure measurements in the right ventricle and PA, and a determination of the magnitude of the shunt by calculating the Qp:Qs ratio \u2013 where Qp is the pulmonary blood flow and the Qs is the systemic blood flow. The standard equation to calculate shunts in the cardiac catheterization laboratory is: \r\n\r\n\t\t\tQp:Qs = SaO2<\/sub> \u2013 SmvO2<\/sub> \/ SpvO2<\/sub> \u2013 SpaO2<\/sub> \r\n\r\nIn this equation, SaO2<\/sub> is the systemic arterial saturation, SmvO2<\/sub> represents the mixed venous saturation, SpvO2<\/sub> is pulmonary vein saturation, and SpaO2<\/sub> is the pulmonary artery saturation. In the absence of an intracardiac shunt, the mixed venous saturation is sampled from the main pulmonary artery. However, in patients with left to right intracardiac shunts, the superior vena cava saturation more accurately reflects a true mixed venous saturation. In patients without an underlying pulmonary pathology, the pulmonary vein saturation is assumed to be 100% and thus equal to the systemic arterial saturation. To avoid a confounding impact of dissolved oxygen, blood samples should be taken at a low FiO2<\/sub> of approximately 0.25-0.3. Therefore, in the operating room, the above equation can be simplified to: \r\n\t\t\t\r\n\t\t\tQp:Qs = SaO2 <\/sub> \u2013 SmvO2 <\/sub> \/ SaO2<\/sub> \u2013 SpaO2<\/sub>\r\n \r\n\r\n\r\nSubstituting the data from the stem into this equation results in a Qp:Qs of 2:1. A Qp:Qs of more than 1.5-2:1 should prompt a return to bypass and revision of the repair. Although most residual VSDs are not hemodynamically significant and are likely to close over time, some studies have shown defects larger than three millimeters in diameter should be addressed surgically, which requires another period of cardioplegic arrest. Interestingly, a recent publication in the Annals of Translational Medicine by Cao et al has reported successful repair of residual VSDs on cardiopulmonary bypass but after aortic unclamping and with a beating heart. They reported good outcomes with no apparent complications. This strategy may represent an unnecessary risk for air embolism to the cerebral and coronary circulation.\r\n\r\n\r\n \r\nREFERENCES \r\n1. Joffe DC, Shi MR, Welker CC. Understanding cardiac shunts. Pediatr Anesth<\/em>. 2018; 28:316-325. doi.org\/10\/1111\/pan.11347 \r\n2. Bibevski S, Ruzmetov M, Mendoza L et al. The destiny of postoperative residual ventricular septal defects after surgical repair in infants and children. World J Pediatr Congenit Heart Surg <\/em>.2020; 11: 438-443. \r\n3. Cao Z, Chai Y, Liu J et al. Revising ventricular septal defect residual shunts without aortic re-cross-clamping: a safe and effective surgical procedure. Ann Transl Med <\/em>. 2020; 8 (18):\r\n1134. doi: 10.21037\/atm-20-5041\r\n”,”hint”:””,”answers”:{“vfqn3”:{“id”:”vfqn3″,”image”:””,”imageId”:””,”title”:”A. 1 : 1″},”zayzn”:{“id”:”zayzn”,”image”:””,”imageId”:””,”title”:”B. 2 : 1″,”isCorrect”:”1″},”syza5″:{“id”:”syza5″,”image”:””,”imageId”:””,”title”:”C. 3 : 1″},”8ejws”:{“id”:”8ejws”,”image”:””,”imageId”:””,”title”:”D. Cannot be calculated with the given information”}}}}}}

{“questions”:{“mil6y”:{“id”:”mil6y”,”mediaType”:”image”,”answerType”:”text”,”imageCredit”:””,”image”:””,”imageId”:””,”video”:””,”imagePlaceholder”:””,”imagePlaceholderId”:””,”title”:”Author: Meera Gangadharan, MD, FASA, FAAP – University of Texas at Houston, McGovern Medical School, Children\u2019s Memorial Hermann Hospital \r\n\r\nA 5-year-old male with a history of Tetralogy of Fallot presents for revision of a right ventricle to pulmonary artery conduit. A multi-modal plan for post-operative pain control includes regional anesthesia. Which of the following regional techniques is MOST likely to provide the best post-operative analgesia in this patient? “,”desc”:”EXPLANATION \r\nEffective pain control after pediatric cardiac surgery is essential for enhanced recovery protocols. These protocols include early extubation, rapid mobilization, reduction in opioid use to minimize side effects, and shortened intensive care unit and hospital stay. Recent trends recommend multimodal approaches to pain management, including regional anesthetic techniques, to reduce systemic opioid use. Neuraxial techniques for pain control are not widely utilized in pediatric cardiac surgery due to the potential risk of bleeding from heparinization during cardiopulmonary bypass. However, there are several peripheral nerve blocks (musculofascial plane blocks), which are efficacious in a multimodal analgesic regimen after pediatric cardiac surgery.\r\n\r\nThe target of a peripheral nerve block for a median sternotomy or intercostal incision is the anterior\/ventral division of the spinal cord, which is the intercostal nerve. Intercostal nerves arise from the anterior rami of the thoracic spinal nerves and lie in between the innermost and internal intercostal muscles. Along its course from the spinal cord, the intercostal nerve branches into collateral and lateral cutaneous branches and finally terminates in the anterior cutaneous branch, which is distributed along the lateral and anterior chest wall. These branches provide sensory innervation to the skin, soft tissue, and muscle on the anterior aspect of the trunk, including the sternum. Thus, blocking the intercostal nerve at any reasonable site is the basis for a peripheral nerve block for cardiac surgery with a median sternotomy or intercostal incision. \r\n\r\nIntercostal muscles lie between the ribs. The pectoralis major muscle overlies the ribs. The intercostal muscles consist of three layers: the external, internal, and innermost intercostal muscles. The intercostal vessels are located on the lower margin of the ribs in the layer between the internal and innermost intercostal muscles. The transverse thoracic muscle lies below the innermost intercostal muscle and may be difficult to identify. The pleura lies below the intercostal muscles and can be identified as a mobile hyperechoic layer. \r\n\r\nThe intercostal nerves arising from the ventral rami of the first six thoracic spinal nerves, supply the sternum, ribs, and intercostal sites. Effective pain relief for a sternotomy or intercostal incision can be provided by blocking the intercostal nerves anywhere along their path (see illustration below). A bilateral parasternal block (PSB) can be performed by the surgeon under direct vision by injecting local anesthetic at a point that is 1.5 to 2 cm lateral to the sternum at the second to sixth intercostal spaces. The PSB has been shown to reduce opioid requirements in the first 24 hours and lower pain scores in pediatric patients after cardiac surgery. \r\n\t\r\n\r\n \r\n\r\nFig. Schema of access points to the intercostal nerve blocks for perioperative pain management for cardiac surgery. Blocking the intercostal nerve at any approachable site is the theory of peripheral nerve block for cardiac surgery with median sternotomy as well as intercostal approach. From: Yamamoto T, Schindler E. Regional anesthesia as part of enhanced recovery strategies in pediatric cardiac surgery. Curr Opin Anaesthesiol<\/em>. 2023;36(3):324-333. doi:10.1097\/ACO.0000000000001262. This is an open access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially without permission from the journal. http:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\r\n\r\nA major disadvantage of the PSB is that multiple injections are required as the target intercostal nerves lie in the layer between the internal intercostal and innermost intercostal muscles, in the intercostal space. Two musculofascial plane blocks are alternative approaches to the parasternal block, which include the pectointercostal fascial block (PIFB) and transversus thoracic plane block (TTPB). Local anesthetic can thus spread along the fascial layers between muscles to cover multiple intercostal levels. Ultrasound guided PIFB and TTPB can be accomplished in the supine position. Local anesthetic is injected between the pectoralis major and the intercostal muscle layer in the PIFB. In the TTPB block, local anesthetic is injected between the innermost intercostal muscle and the transversus thoracic muscle. The PIFB has been reported to reduce opioid requirements and postoperative pain in the first 24 hours after surgery, as well as reducing the time to extubation and length of hospital stay. A retrospective study in pediatric patients demonstrated reduced intra and postoperative fentanyl use, postoperative pain scores and time to extubation. The PIFB and TTPB fascial block do not cover chest tube sites in the upper abdomen. Therefore, a rectus sheath block (RSB) is a useful adjunct to provide adequate analgesia after cardiac surgery. The efficacy of combining a RSB on the side ipsilateral to the chest tube and bilateral PIFBs has recently been described in pediatric patients after cardiac surgery in a retrospective, single center study. In this study, these interventions were associated with decreases in postoperative opioid use, pain scores and hospital length of stay. \r\n\r\nThe pectoral nerves blocks (PECS 1 and PECS 2) anesthetize the pectoral nerves, the third through sixth intercostal nerves, intercostobrachial nerve, and the long thoracic nerve. These blocks are performed by depositing local anesthetic between the pectoralis minor and major muscles (PECS 1) and between pectoralis minor and serratus anterior (PECS 2) muscles respectively. These blocks are more effective for surgical incisions that are further from the midline such as thoracotomy incisions and incisions for pacemaker implantations and breast surgery, but they are inadequate for a midline sternotomy incision. \r\n\r\nThe transversus abdominis plane block is inadequate for sternotomy and upper abdominal midline pain but is useful for procedures with lower abdominal incisions.\r\n\r\n\r\n\r\n \r\nREFERENCES \r\nYamamoto T, Schindler E. Regional anesthesia as part of enhanced recovery strategies in pediatric cardiac surgery. Curr Opin Anaesthesiol<\/em>. 2023;36(3):324-333. doi:10.1097\/ACO.0000000000001262\r\n\r\nRaj N. Regional anesthesia for sternotomy and bypass-Beyond the epidural. Paediatr Anaesth<\/em>. 2019;29(5):519-529. doi:10.1111\/pan.13626\r\n\r\nChaudhary V, Chauhan S, Choudhury M, et al. Parasternal intercostal block with ropivacaine for postoperative analgesia in pediatric patients undergoing cardiac surgery: a double-blind, randomized, controlled study. J Cardiothorac Vasc Anesth <\/em>.2012; 26:439\u2013442\r\n\r\nBloc S, Perot BP, Gibert H, et al. Efficacy of parasternal block to decrease intraoperative opioid use in coronary artery bypass surgery via sternotomy: a randomized controlled trial. Reg Anesth Pain Med<\/em>. 2021;46(8):671-678. doi:10.1136\/rapm-2020-102207\r\n\r\nFuller S, Kumar SR, Roy N, et al. The American Association for Thoracic Surgery Congenital Cardiac Surgery Working Group 2021 consensus document on a comprehensive perioperative approach to enhanced recovery after pediatric cardiac surgery. J Thorac Cardiovasc Surg <\/em>.2021;162(3):931-954. doi:10.1016\/j.jtcvs.2021.04.072\r\n\r\nTran DQ, Bravo D, Leurcharusmee P, Neal JM. Transversus Abdominis Plane Block: A Narrative Review. Anesthesiology<\/em>. 2019;131(5):1166-1190. doi:10.1097\/ALN.0000000000002842\r\n\r\nKumar AK, Chauhan S, Bhoi D, Kaushal B. Pectointercostal fascial block (PIFB) as a novel technique for postoperative pain management in patients undergoing cardiac surgery. J Cardiothorac Vasc Anesth <\/em>.2021; 35:116\u2013122.\r\n\r\nZhang Y, Gong H, Zhan B, Chen S. Effects of bilateral Pecto-intercostal Fascial Block for perioperative pain management in patients undergoing open cardiac surgery: a prospective randomized study. BMC Anesthesiol<\/em>. 2021; 21:175.\r\n\r\nEinhorn LM, Andrew BY, Nelsen DA, Ames WA. Analgesic effects of a novel combination of regional anesthesia after pediatric cardiac surgery: a retrospective cohort study. J Cardiothorac Vasc Anesth<\/em>. 2022; 36:4054\u20134061.\r\n\r\nCakmak M, Isik O. Transversus thoracic muscle plane block for analgesia after pediatric cardiac surgery. J Cardiothorac Vasc Anesth<\/em>. 2021; 35:130\u2013136\r\n”,”hint”:””,”answers”:{“7gwtw”:{“id”:”7gwtw”,”image”:””,”imageId”:””,”title”:”A.\tPECS 1 and PECS 2 blocks”},”cs781″:{“id”:”cs781″,”image”:””,”imageId”:””,”title”:”B.\tPectointercostal fascial block and rectus sheath block”,”isCorrect”:”1″},”8j2ni”:{“id”:”8j2ni”,”image”:””,”imageId”:””,”title”:”C.\tTransversus abdominis plane block”}}}}}

{“questions”:{“d7guh”:{“id”:”d7guh”,”mediaType”:”image”,”answerType”:”text”,”imageCredit”:””,”image”:””,”imageId”:””,”video”:””,”imagePlaceholder”:””,”imagePlaceholderId”:””,”title”:”Author: Meera Gangadharan, MD, FASA, FAAP – University of Texas at Houston \r\n\r\nA four-year-old male presents for computed tomography of the brain due to a history of seizures in setting of playing soccer. During inhalational induction, the patient becomes fearful and anxious with a heart rate of 190. Within seconds, there is an abrupt change in the ECG from normal sinus rhythm to a wide-complex, bidirectional ventricular tachycardia, which proves unresponsive to epinephrine. A baseline electrocardiogram was normal. What is the MOST likely diagnosis?”,”desc”:”EXPLANATION \r\nThe cardiac channelopathies are a heterogeneous group of arrhythmias that are associated with sudden cardiac death. The etiology is typically abnormal function of the sodium, potassium, and\/or calcium channel within the myocardial cell membrane. There is a strong genetic component and, therefore, obtaining a detailed family history and genetic testing is essential. Clinical features include syncope, seizures, or sudden cardiac death. \r\n\r\nCatecholaminergic polymorphic ventricular tachycardia (CPVT) is an inherited, congenital arrhythmia which usually manifests in children and young adults as dizziness, presyncope, syncope, seizures (secondary to syncope), and sudden cardiac death. It has an incidence of approximately one in 10,000. CPVT is characterized by a rapid polymorphic and bidirectional ventricular tachycardia (VT) occurring during physical exercise or emotional stress \u2013 see image below, used under Creatice Commons License. These patients are asymptomatic at rest and have normal resting electrocardiograms without structural cardiac abnormalities. \r\n\r\n \r\n\r\nElectrocardiogram during exercise stress testing demonstrates increasing frequency of ventricular arrhythmias, degrading from bigeminy to a typical bidirectional ventricular tachycardia. From Behere SP, Weindling SN. Catecholaminergic polymorphic ventricular tachycardia: An exciting new era. Ann Pediatr Cardiol <\/em>.2016;9(2):137-146. doi:10.4103\/0974-2069.180645. This is an open access article distributed under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike 3.0 License, which allows others to remix, tweak, and build upon the work non-commercially, as long as the author is credited and the new creations are licensed under the identical terms.\r\nhttps:\/\/www.ncbi.nlm.nih.gov\/pmc\/articles\/PMC4867798\/ \r\nCPVT is caused by abnormal intracellular regulation of calcium in the cardiomyocyte resulting in ventricular ectopy, polymorphic couplets, ventricular fibrillation (VF), and ventricular tachycardia (VT) with a characteristic bidirectional morphology. Autosomal dominant mutations in the ryanodine receptor 2 (RYR2) gene account for 60-70% of cases, and autosomal recessive mutations in the calsequestrin 2 (CASQ2) gene account for an additional 10-15% of CPVT cases. Although most cases are familial, some individuals may present with de novo mutations in the absence of a family history of CPVT. \r\n\r\nThe five therapeutic options for the treatment of CPVT include the following: (1) lifestyle modifications; (2) beta-blockers; (3) implantable cardioverter-defibrillator (ICD); (4) flecainide; and (5) left cardiac sympathetic denervation. Life-style changes include avoiding triggers that cause increased sympathetic activity such as strenuous exercise and competitive sports. However, patients can partake in sports if they are asymptomatic and compliant on their medical regimens. Long-acting beta blockers, such as nadolol, are first line medical therapy. Flecanide can be effective in patients who are symptomatic despite maximal beta blocker therapy. Left cardiac sympathetic denervation (LCSD) is an effective option for patients who are still symptomatic despite maximal medical therapy. LCSD involves resection of the lower half of T1 and parts of the T2, T3 and T4 thoracic ganglia. Typically, ICD insertion is reserved for patients who are not fully responsive to medical therapy. However, ICD implantation may lead to several undesirable and potentially life-threatening complications and side effects, including the following: (1) inappropriate defibrillation; (2) catecholamine surge due to device discharge, which can potentially cause a \u201cstorm\u201d of ventricular tachycardia, and (3) complications related to the device such as pocket infection, lead fracture and displacement, endocarditis, vessel stenosis, and need for reimplantation of the ICD. In a systematic review of 53 studies describing 1,429 patients with a median age of 15 years and CPVT treated with ICD placement, 19.6% of patients experienced a storm which resulted in the death of 1.4% of patients.\r\n\r\nIt is important to have a high index of suspicion for CPVT in patients with a history of syncope with intense exertion, as epinephrine can be detrimental and cause further deterioration. Bellamy et al described three patients with the diagnosis of CPVT. Collectively, there were two episodes of ventricular tachycardia and one episode of ventricular fibrillation that were unresponsive to repeated doses of epinephrine but that resolved with administration of opiates. Two patients were rescued with extracorporeal membrane oxygenation and then underwent epinephrine challenge that resulted in polymorphic, bidirectional ventricular tachycardia, thereby confirming the diagnosis of CPVT. \r\n\r\nLong QT syndrome is characterized by the hallmark feature of prolongation of the QT interval on ECG, reflecting delayed myocardial repolarization, and is unlikely in this case as the patient had a previously normal ECG. Other hallmark features include polymorphic VT leading to syncope and sudden death. Brugada syndrome is characterized by abnormalities in the right ventricular outflow tract, which are responsible for characteristic ECG changes and the development of polymorphic VT\/VF. The key diagnostic feature of Brugada syndrome is the presence of a \u201ctype I Brugada ECG pattern \u201cin the right ventricular leads on the 12 lead ECG. This consists of a partial right bundle branch block, J point elevation, and coved ST segment elevation followed by a T wave inversion. Brugada syndrome is unlikely in this patient with a previously normal ECG. \r\n \r\n\r\n \r\nREFERENCE \r\nKim CW, Aronow WS, Dutta T, Frenkel D, Frishman WH. Catecholaminergic Polymorphic Ventricular Tachycardia. Cardiol Rev <\/em>. 2020;28(6):325-331. doi:10.1097\/CRD.0000000000000302 \r\nMellor GJ, Behr ER. Cardiac channelopathies: diagnosis and contemporary management [published online ahead of print, 2021 Feb 15]. Heart <\/em>.2021;heartjnl-2019-316026. doi:10.1136\/heartjnl-2019-316026 \r\nBellamy D, Nuthall G, Dalziel S, Skinner JR. Catecholaminergic Polymorphic Ventricular Tachycardia: The Cardiac Arrest Where Epinephrine Is Contraindicated. Pediatr Crit Care Med<\/em>. 2019;20(3):262-268. doi:10.1097\/PCC.0000000000001847 \r\nRoston TM, Jones K, Bos M et al. Implantable cardioverter-defibrillator use in catecholaminergic polymorphic ventricular tachycardia: A systematic review. Heart Rhythm. 2018; 15:1791-1799. https:\/\/doi.org\/10.1016\/j.hrthm.2018.06.046\r\n”,”hint”:””,”answers”:{“jfcoi”:{“id”:”jfcoi”,”image”:””,”imageId”:””,”title”:”A. Brugada syndrome”},”t6kbq”:{“id”:”t6kbq”,”image”:””,”imageId”:””,”title”:”B. Long QT syndrome”},”1y80o”:{“id”:”1y80o”,”image”:””,”imageId”:””,”title”:”C. Catecholaminergic polymorphic ventricular tachycardia\r\n\r\n”,”isCorrect”:”1″}}}}}

{“questions”:{“3b0vg”:{“id”:”3b0vg”,”mediaType”:”image”,”answerType”:”text”,”imageCredit”:””,”image”:””,”imageId”:””,”video”:””,”imagePlaceholder”:””,”imagePlaceholderId”:””,”title”:”Author: Meera Gangadharan, MD, FASA, FAAP – University of Texas at Houston \r\n\r\nA neonate presents with cyanosis, tachypnea, and poor oral intake. Vital signs are HR 180, BP 60\/40, RR 64, S_{p<\/sub>O2<\/sub> 75% in room air. A transthoracic echocardiogram demonstrates severe right atrial enlargement, severely depressed right ventricular function with moderate tricuspid regurgitation and leaflets in the normal location, and a severely thinned right ventricular free wall with bidirectional shunting across a patent foramen ovale. Left heart structures are normal. An electrocardiogram shows sinus tachycardia. What is the MOST likely diagnosis?”,”desc”:”EXPLANATION \r\nThis newborn has a rare cardiac condition called Uhl\u2019s anomaly, which is characterized by a very dilated, and poorly functioning right ventricle (RV). The free wall of the RV is dilated and paper-thin due to the absence of a myocardial muscle layer except for the cardiac apex where muscular trabeculations may be present. The pathogenesis is still debated but abnormal apoptosis of the RV myocardium is the most likely explanation as the myocardium is evident in early gestation. Biopsies are also notable for the absence of myocardial inflammation.\r\nFetal diagnosis can be challenging but has important implications for prognosis as Uhl\u2019s anomaly differs from other diagnoses that are similar. The papillary muscle of the tricuspid valve can be mistaken for the septal leaflet of the tricuspid valve, making it appear to be apically displaced. Magnetic resonance imaging (MRI) will typically demonstrate a pathognomonic absence of the myocardial muscle layer between the RV epicardium and endocardium. This is demonstrated in the illustration below. Patients usually present in the newborn period or infancy with signs of right heart failure, although there are case reports of adults with this condition. There may be tricuspid and pulmonary valve abnormalities as well. Left heart structures and the coronary arteries are typically normal. \r\nTreatment includes medical management with diuretics, digoxin, and beta blockers. Surgical options are generally determined by the specific anatomical substrate, but generally involve RV-exclusion procedures such as the Glenn, Fontan or one-and-a-half ventricle repairs which may include plication of excess right ventricular free wall. Cardiac transplantation may also be a treatment modality. \r\nThe two main diagnoses on the differential with Uhl\u2019s anomaly are arrhythmogenic right ventricular cardiomyopathy (ARVC, previously called arrhythmogenic right ventricular dysplasia) and Ebstein\u2019s anomaly. ARVC is characterized by arrhythmias and sudden cardiac death, usually in late childhood or young adulthood. Characteristic MRI appearances of ARVC are the presence of patches of fibrofatty infiltration between the layers of endocardium and epicardium. The left ventricle may also be involved in arrhythmogenic cardiomyopathy. Ebstein\u2019s anomaly is characterized by the apical displacement of the septal leaflet of the tricuspid valve with the sail-like appearance of the anterior leaflet. In contrast, the tricuspid valve leaflets insert at the true annulus of the tricuspid valve in Uhl\u2019s anomaly. The image below is an illustration of the typical cardiac magnetic resonance imaging in Uhl\u2019s anomaly. \r\n\r\n\r\n \r\nCardiac magnetic resonance, in steady-state free precession, four-chamber sequence showing marked right chamber dilatation. The tricuspid valve (TV) has normal positioning. A moderator band (MB) and a medium-volume pericardial effusion (PE) are visualized. LA<\/em>, Left atrium; LV<\/em>, left ventricle;RA<\/em>, right atrium;RV<\/em>, right ventricle. From Faria et al. https:\/\/doi.org\/10.1016\/j.case.2020.05.014. This is an open access article under the CC BY-NC-ND license (http:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/). \r\n\r\n \r\nREFERENCES \r\nGerlis LM, Schmidt-Ott SC, Ho SY, Anderson RH. Dysplastic conditions of the right ventricular myocardium: Uhl’s anomaly vs arrhythmogenic right ventricular dysplasia. Br Heart J<\/em>. 1993;69(2):142-150. doi:10.1136\/hrt.69.2.142 \r\nMihos CG, Larrauri-Reyes M, Yucel E, Santana O. Clinical presentation, and echocardiographic characteristics of Uhl’s anomaly.Echocardiography<\/em>. 2017;34(2):299-302\r\nFaria B, von Hafe P, Ferreira FC, et al. Uhl’s Anomaly: 10 Years of Follow-Up of an Unoperated Patient. CASE (Phila)<\/em>. 2020;4(5):351-355. Published 2020 Jun 24. doi:10.1016\/j.case.2020.05.014 \r\nKalita JP, Dutta N, Awasthy N, et al. Surgical Options for Uhl’s Anomaly.World J Pediatr Congenit Heart Surg<\/em>. 2017;8(4):470-474. doi:10.1177\/2150135117710940 \r\nVaujois L, van Doesburg N, Raboisson MJ. Uhl’s anomaly: a difficult prenatal diagnosis. Cardiol Young<\/em>. 2015;25(3):580-583. doi:10.1017\/S1047951114000651\r\nCorrado D, Zorzi A, Cipriani A, et al. Evolving Diagnostic Criteria for Arrhythmogenic Cardiomyopathy. J Am Heart Assoc<\/em>. 2021;10(18): e021987.\r\n\r\n”,”hint”:””,”answers”:{“i1drd”:{“id”:”i1drd”,”image”:””,”imageId”:””,”title”:”A. Arrhythmogenic right ventricular cardiomyopathy “},”xsk3d”:{“id”:”xsk3d”,”image”:””,”imageId”:””,”title”:”B. Uhl\u2019s anomaly”,”isCorrect”:”1″},”dvhxa”:{“id”:”dvhxa”,”image”:””,”imageId”:””,”title”:”C. Ebstein\u2019s anomaly”}}}}}}

{“questions”:{“9i62x”:{“id”:”9i62x”,”mediaType”:”image”,”answerType”:”text”,”imageCredit”:””,”image”:”https:\/\/ccasociety.org\/wp-content\/uploads\/2023\/08\/Picture1-CCAS-832023.png”,”imageId”:”6703″,”video”:””,”imagePlaceholder”:””,”imagePlaceholderId”:””,”title”:”Author: Nicholas Houska, DO and Dustin Nash, MD – University of Colorado, Children\u2019s Hospital Colorado \r\n\r\nA 4-month-old infant has just undergone repair of Tetralogy of Fallot with a transannular patch, removal of right ventricular muscle bundles and ventricular septal defect (VSD) closure. Six hours postoperatively, the patient\u2019s heart rate gradually increases to 230 beats per minute with concurrent hypotension. The electrocardiogram (ECG) demonstrates a narrow complex tachycardia. An atrial electrogram is performed and illustrated below (From author\u2019s library). What is the MOST likely diagnosis?\r\n\r\n\r\n”,”desc”:”EXPLANATION \r\nJunctional ectopic tachycardia (JET) is an arrythmia most frequently seen in infants and children. It may be congenital in nature, but more commonly occurs postoperatively after cardiac surgery. JET originates from the area near the atrioventricular (AV) node and Bundle of His. It is most frequently associated with VSD closure, repair of Tetralogy of Fallot, and atrioventricular septal defect repair. Other risk factors for the development of JET include age less than 6 months, prolonged surgical time, prolonged cross clamp time, and the use of inotropes. The pathophysiology of postoperative JET is incompletely understood but is thought to be associated with trauma, stretch, and ischemia of the conduction system leading to the loss of cell membrane integrity. The etiology is likely multi-factorial but is ultimately related to increased sympathetic tone and automaticity. JET can be associated with significant morbidity and mortality. Additionally, it may be difficult to diagnose and treat. JET occurs with a frequency of 5-10% after congenital cardiac surgery. For these reasons, it is important for clinicians to have a high index of suspicion for JET and provide prompt diagnosis and treatment. \r\n\r\nJunctional ectopic tachycardia is typically a narrow complex tachycardia with ventriculo-atrial (VA) dissociation. The ventricular rate is typically irregular and higher than the atrial rate except in the less common instance of one to one (1:1) VA conduction. Onset is gradual with no initiating ectopic beat. Patients with JET have a heart rate greater than the 95th percentile for age, otherwise it is termed accelerated junctional rhythm. Diagnosis can be difficult on a standard surface ECG due to the difficulty in identifying atrial depolarization (P wave). In patients with atrial pacing leads, an atrial electrogram can be performed by connecting the atrial lead directly to one of the leads on a standard ECG. This allows identification of atrial depolarization in side by side comparison with ventricular depolarization in the other leads. The ECG below shows dissociation of ventricular depolarization (V) at a rate of 195 beats per minute (bpm) from atrial depolarization (A) at a rate of 170 bpm, which confirms the diagnosis of JET. Red squares are highlighting the association of QRS complexes on the standard ECG with the signals on the atrial electrogram. \r\n\r\nPostoperative JET is typically self-limited, but treatment may be indicated for hemodynamic instability. Treatment includes attenuating sympathetic stimulation by reducing inotrope dose, optimizing analgesia and sedation, and administration of dexmedetomidine. Correction of electrolytes and induction of mild hypothermia are also mainstays of treatment. Adenosine will not terminate JET but will cause AV dissociation when JET is difficult to identify. Amiodarone is the drug of choice for treatment. In refractory cases with hemodynamic instability, extracorporeal membrane oxygenation and\/or catheter ablation may be indicated. \r\n\t\r\n(Source: author\u2019s library)\r\n \r\nREFERENCES \r\nAlasti M, Mirzaee S, Machado C, et al. Junctional ectopic tachycardia (Jet). J Arrhythmia <\/em>.2020;36(5):837-844.\r\n\r\nKaltman JR, Madan N, Vetter VL, Rhodes LA. Arrhythmias and sudden cardiac death. In: Pediatric Cardiology<\/em>. Elsevier; 2006:171-194.\r\n\r\nSasikumar N, Kumar R, Balaji S. Diagnosis and management of junctional ectopic tachycardia in children. Ann Pediatr Card<\/em>. 2021;14(3):372.\r\n\r\nAshraf M, Goyal A. Junctional ectopic tachycardia. In: StatPearls<\/em>. StatPearls Publishing; 2023. Accessed July 21, 2023. https:\/\/www.ncbi.nlm.nih.gov\/books\/NBK560851\/\r\n”,”hint”:””,”answers”:{“wud5a”:{“id”:”wud5a”,”image”:””,”imageId”:””,”title”:”A. Atrioventricular nodal reentrant tachycardia (AVNRT)”},”kh7ns”:{“id”:”kh7ns”,”image”:””,”imageId”:””,”title”:”B. Ventricular Tachycardia”},”ptlqh”:{“id”:”ptlqh”,”image”:””,”imageId”:””,”title”:”C. Junctional Ectopic Tachycardia”,”isCorrect”:”1″}}}}}