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

{“questions”:{“joghu”:{“id”:”joghu”,”mediaType”:”image”,”answerType”:”text”,”imageCredit”:””,”image”:””,”imageId”:””,”video”:””,”imagePlaceholder”:””,”imagePlaceholderId”:””,”title”:”Authors: Christopher Busack MD, Chinwe Unegbu MD, and Daniela Perez-Velasco DO \u2013 Children\u2019s National Hospital \r\n\r\nAn 11-year-old adolescent male with a history of recurrent syncope after intense emotional distress and a structurally normal heart presents for a cardioneuroablation procedure. Which of the following arrhythmias represents the STRONGEST indication for the cardioneuroablation procedure targeting epicardial parasympathetic ganglionic plexuses? “,”desc”:”EXPLANATION \r\nNeurally mediated syncope (NMS) or Neurally Mediated Reflex Syncope (NMRS) traditionally refers to syncope owing to an imbalance of sympathetic and parasympathetic tone. Enhanced parasympathetic tone due to vagal nerve stimulation can lead to dramatic slowing of the sinus node or atrioventricular nodes resulting in prolonged sinus bradycardia, junctional rhythm, pauses, sinus arrest, asystole or second or third-degree atrioventricular block. Triggering factors for NMS vary widely and include orthostatic stress, emotional stress, urination, coughing, swallowing, physical exercise, and stimulation of the carotid sinus in susceptible patients.\r\nTypically, a patient with NMS will feel warmth, nausea, and lightheadedness and may appear pale before abruptly losing consciousness. Occasionally, patients do not experience any symptoms prior to syncope. Prior to a diagnosis of NMS, other causes of syncope must be ruled out by means of history, physical examination and appropriate tests. Frequently, the cause of syncope is identified during initial clinical evaluation and no further testing is needed. When the cause of syncope is not clear, a stepwise approach is required for diagnosis. The differential diagnosis for syncope is broad and includes structural heart disease, neurologic disease, cardiac disease, and arrhythmias such as life-threatening ventricular tachycardia, rapid supraventricular tachycardia and prolonged asystole. Prolonged asystole is the most common arrythmia (> 50%) leading to syncope in patients without significant structural heart disease and a normal ECG. If an arrhythmia is suspected, a 24-hour Holter or long-term event monitor can be used to establish the diagnosis. Invasive electrophysiology studies can be performed to distinguish whether syncope is caused by an arrhythmia such as ventricular tachycardia, sinus node dysfunction or intracardiac conduction delay. Often, syncope is due to a mixed pathology. \r\nIn the absence of structural heart disease and with a suspicion of NMS, a head-up-tilt-table (HUTT) test is performed to confirm the diagnosis. This is a provocative test with an orthostatic challenge to determine a patient\u2019s susceptibility to syncope. The test is considered positive if symptoms are reproduced along with objective evidence of a sudden decrease in blood pressure or decrease in heart rate. \r\n\r\nMedical therapy for NMS consists of beta blockers, alpha agonists, selective serotonin reuptake inhibitors, fludrocortisone, and anticholinergics. Pacemaker therapy can be helpful for patients refractory to medical therapy. According to the American College of Cardiology\/American Heart Association, minimal carotid sinus pressure that induces asystole greater than three seconds in the absence of medications that depress sinoatrial or atrioventricular (AV) node conduction is considered a class I indication for pacemaker placement when the result is recurrent syncope. NMS with severe bradycardia reproduced during HUT testing is a class IIb indication for pacemaker insertion. The North American Vasovagal Pacemaker study published in 1993, which involved 54 patients with frequent syncopal spells and positive HUT tests, demonstrated that recurrence of syncope was significantly reduced in patients with pacemakers (22%) versus those without pacemakers (70%). Though pacemaker therapy is used in the treatment of NMS, the decision to implant a pacemaker is difficult and challenging in young patients with structurally normal hearts. \r\n\r\nA novel therapy for NMS is cardioneuroablation (CNA) and was first described by Pachon in 2005 in 21 patients with a mean age of 48 years and diagnoses varying from NMS, functional high grade atrioventricular block and sinus node dysfunction. The CNA procedure is performed percutaneously and is based on radiofrequency ablation. The therapy targets vagal efferent postganglionic neurons innervating the sinoatrial (SA) or atrioventricular (AV) node. The postganglionic neurons are primarily located in discrete epicardial structures known as fat pads. Long-term vagal denervation of the atria, SA and AV nodes can be achieved by radiofrequency catheter ablation of these fat pads. \r\n\r\nIn 2017, Aksu and colleagues conducted a literature review to assess efficacy of CNA for treatment of NMS, which included five observational studies and five case reports. The review demonstrated reduced vagal tone lasting for at least 12 months after the procedure with improved tolerance of repeated head-up tilt testing. An additional study by Pachon et al published in 2011 demonstrated a significant decrease in atropine test positivity following CNA. However, in long-term follow up, patients demonstrated increased atropine test positivity suggesting either partial reinnervation and\/or partial ablation. \r\n\r\nAlthough initial reports of CNA have been positive, no formal guidelines exist regarding specific indications or contraindications for the procedure. The 2018 European Society of Cardiology guidelines do acknowledge the novel procedure as a possible treatment modality for NMS, but state that current evidence is insufficient to confirm the efficacy of vagal ganglia ablation. A 2022 prospective, randomized control trial by Piotrowski and colleagues included patients with documented symptomatic cardioinhibitory or mixed vasovagal syncope and positive atropine test. Patients who underwent CNA had less frequent syncope and better quality of life at 24-month follow-up. \r\n\r\nReports of complications from CNA have been sparse. A case report by Kumthekar et al published in 2020 describes a pediatric patient that developed paroxysmal atrial fibrillation after CNA. The arrhythmia was well controlled with medical therapy, and subsequently resolved. A study of long-term outcomes after CNA, published by Sun et al in 2016, noted one patient with inappropriate but transient sinus tachycardia. \r\n\r\nChoice A is the correct answer as high-grade third-degree AV block in a structurally normal heart is more likely to be related to NMS and would be a strong indication for CNA. Choices B and C are not typical arrhythmias related to NMS but rather cardiac disease. Choice D, sinus arrhythmia, is not correct as it is a commonly encountered variation of normal sinus rhythm. \r\n\r\n\r\nREFERENCES \r\n1.\tPachon JC, Pachon EI, Pachon JC, et al. \”Cardioneuroablation\”–new treatment for neurocardiogenic syncope, functional AV block and sinus dysfunction using catheter RF-ablation. Europace.<\/em> 2005;7(1):1-13. doi: 10.1016\/j.eupc.2004.10.003 \r\n\r\n2.\tPachon JC, Pachon EI, Cunha Pachon MZ, et. al. Catheter ablation of severe neurally meditated reflex (neurocardiogenic or vasovagal) syncope: cardioneuroablation long-term results. Europace.<\/em> 2011;13:1231\u20131242. doi:10.1093\/europace\/eur163\r\n\r\n3.\tZaqqa M, Massumi A. Neurally mediated syncope. Tex Heart Inst J.<\/em> 2000;27(3):268-272. \r\n\r\n4.\tKumthekar RN, Sumihara K, Moak JP. Pediatric radiofrequency ablation of cardiac parasympathetic ganglia to achieve vagal denervation. HeartRhythm Case Rep.<\/em> 2020;6(11):879-883. doi: 10.1016\/j.hrcr.2020.09.004 \r\n\r\n5.\tAksu T, G\u00fcler TE, Bozyel S, et. al. Cardioneuroablation in the treatment of neurally mediated reflex syncope: a review of the current literature. Turk Kardiyol Dern Ars.<\/em> 2017;45(1):33-41. doi: 10.5543\/tkda.2016.55250. \r\n\r\n6.\tHussain S, Raza Z, Kumar TVV, et al. Diagnosing Neurally Mediated Syncope Using Classification Techniques. J Clin Med.<\/em> 2021;10(21):5016. doi: 10.3390\/jcm10215016 \r\n\r\n7.\tTask Force for the Diagnosis and Management of Syncope; European Society of Cardiology (ESC); European Heart Rhythm Association (EHRA); Heart Failure Association (HFA); Heart Rhythm Society (HRS), Moya A, Sutton R, Ammirati F, et. al. Guidelines for the diagnosis and management of syncope (version 2009). Eur Heart J.<\/em> 2009;30(21):2631-2671. doi: 10.1093\/eurheartj\/ehp298 \r\n\r\n8.\tMoya A, Brignole M, Menozzi C, et al; International Study on Syncope of Uncertain Etiology (ISSUE) Investigators. Mechanism of syncope in patients with isolated syncope and in patients with tilt-positive syncope. Circulation.<\/em> 2001;104(11):1261-1267. doi: 10.1161\/hc3601.095708 \r\n\r\n9.\tGregoratos G, Cheitlin M, Conill A, et al. ACC\/AHA Guidelines for Implantation of Cardiac Pacemakers and Antiarrhythmia Devices: Executive Summary\u2014a report of the American College of Cardiology\/American Heart Association Task Force on Practice Guidelines (Committee on Pacemaker Implantation). Circulation.<\/em>1998;97:1325-1335. doi:10.1161\/01.cir.97.13.1325 \r\n\r\n10.\tConnolly SJ, Sheldon R, Roberts RS, et al. The North American Vasovagal Pacemaker Study (VPS). A randomized trial of permanent cardiac pacing for the prevention of vasovagal syncope. J Am Coll Cardiol. <\/em>1999;33:16-20. doi:10.1016\/s0735-1097(98)00549-x \r\n\r\n11.\tSun W, Zheng L, Qiao Y, et al. Catheter Ablation as a Treatment for Vasovagal Syncope: Long-Term Outcome of Endocardial Autonomic Modification of the Left Atrium. J Am Heart Assoc. <\/em> 2016;5(7):e003471.doi:10.1161\/JAHA.116.003471 \r\n\r\n12.\tBrignole M, Moya A, de Lange FJ, et al; ESC Scientific Document Group. 2018 ESC Guidelines for the diagnosis and management of syncope. Eur Heart J. 2018 Jun 1;39(21):1883-1948. doi: 10.1093\/eurheartj\/ehy037. \r\n\r\n13.\tPiotrowski R, Baran J, Sikorska A, Krynski T, Kulakowski P. Cardioneuroablation for Reflex Syncope: Efficacy and Effects on Autonomic Cardiac Regulation-A Prospective Randomized Trial. JACC Clin Electrophysiol. 2022 Aug 28:S2405-500X(22)00680-6. doi: 10.1016\/j.jacep.2022.08.011.\r\n”,”hint”:””,”answers”:{“lpdtd”:{“id”:”lpdtd”,”image”:””,”imageId”:””,”title”:”A. Third degree atrioventricular block “,”isCorrect”:”1″},”9gaf7″:{“id”:”9gaf7″,”image”:””,”imageId”:””,”title”:”B. Non-sustained ventricular tachycardia”},”melsv”:{“id”:”melsv”,”image”:””,”imageId”:””,”title”:”C. Paroxysmal supraventricular tachycardia”},”uxqjt”:{“id”:”uxqjt”,”image”:””,”imageId”:””,”title”:”D. Sinus arrhythmia”}}}}}

{“questions”:{“kiytl”:{“id”:”kiytl”,”mediaType”:”image”,”answerType”:”text”,”imageCredit”:””,”image”:””,”imageId”:””,”video”:””,”imagePlaceholder”:””,”imagePlaceholderId”:””,”title”:”Authors: Daniela Perez-Velasco DO, Chinwe Unegbu MD, and Christopher Busack MD \u2013 Children\u2019s National Hospital \r\n\r\nAn 8-year-old male child with a history of Noonan syndrome and mild supravalvar pulmonary stenosis presents for dental rehabilitation surgery. Which of the following is the MOST LIKELY hematologic abnormality seen in patients with Noonan syndrome?”,”desc”:””,”hint”:””,”answers”:{“teocu”:{“id”:”teocu”,”image”:””,”imageId”:””,”title”:”A. Anemia”},”o8phx”:{“id”:”o8phx”,”image”:””,”imageId”:””,”title”:”B. Polycythemia”},”uafba”:{“id”:”uafba”,”image”:””,”imageId”:””,”title”:”C. Thrombocytopenia”,”isCorrect”:”1″},”a5nrm”:{“id”:”a5nrm”,”image”:””,”imageId”:””,”title”:”D. Neutropenia”}}}},”results”:{“391u2”:{“id”:”391u2″,”title”:””,”image”:””,”imageId”:””,”min”:”0″,”max”:”1″,”desc”:”Noonan syndrome (NS) was first described in 1963 and has an estimated prevalence of 1 in 1000 to 2500 live births. Initially considered to be a type of \u201cmale Turner syndrome\u201d, Dr. Jaqueline Noonan then described NS as clinically and etiologically unique from Turner syndrome and occurring in both males and females. Patients with NS have a normal karyotype, and most cases are likely secondary to de novo mutations, which are inherited in an autosomal dominant manner. Patients with NS demonstrate a wide range of phenotypic features including short stature, hypertelorism, ptosis, undescended testes, skeletal malformations, mild cognitive impairment, and congenital cardiac malformations. The incidence of congenital cardiac defects in NS is approximately 60%, of which the most common is pulmonary valve stenosis (50%). \r\n\r\nBleeding disorders are common in patients with NS and represent a serious, yet poorly defined, complication of NS. In her first report, Dr. Noonan described a NS patient with persistent thrombocytopenia. The estimated frequency of bleeding diatheses in NS is between 20-65%. There are reports in the literature of cases of decreased coagulation factor levels (factors II and XI), von Willebrand disease (vWD), thrombocytopenia, and abnormal platelet function. A study published in 1997 by Singer et al. described findings of a literature review of bleeding disorders in NS citing multiple types of hemostatic abnormalities with a wide range of clinical presentations. The most frequently described hemostatic abnormality was low Factor XI levels but thrombocytopenia and abnormal platelet function were also common. NS patients with hemostatic abnormalities may present with easy bruising and prolonged bleeding. Since there is no consistent pattern of hemostatic defects in this patient population, a definitive coagulation abnormality may not be identified in some NS patients. One potential factor leading to increased bleeding tendency may be shear stress due to pulmonary valve stenosis, resulting in reduced quality of functional von Willebrand factor. \r\n\r\nThe increased likelihood of hemostatic abnormalities in NS patients has important clinical implications. Anesthesiologists need to be aware of the increased risk of bleeding since NS patients often present for cardiac catheterization, open heart surgery, and noncardiac surgical procedures. Given the increased risk of perioperative bleeding, it may be advisable that NS patients have a full hematology workup and screening prior to invasive procedures. Evaluation should include a careful history of bleeding tendencies (i.e. bruising, epistaxis), a complete blood count, and coagulation profile. If any of these tests yield abnormal results, it is warranted to consider a hematology consultation for a more extensive evaluation. A hematology evaluation may include individual factor levels, tests of platelet function, and perhaps a bone marrow biopsy. Specific recommendations from a hematologist regarding aspirin use is advisable in NS patients given the risk of baseline platelet abnormalities. \r\n\r\nAnswer C is correct because patients with NS have a high incidence of hemostatic abnormalities including thrombocytopenia. Answers A,B, and D are not correct because these are not typical findings in NS. \r\n\r\nREFERENCES \r\n1.\tNoonan J.A., Ehmke D.A.: Associated noncardiac malformations in children with congenital heart disease. J Pediatr.<\/em> 1963; 63: pp. 468-470. \r\n2.\tNoonan JA. Hypertelorism With Turner Phenotype: A New Syndrome With Associated Congenital Heart Disease. American journal of diseases of children (1960). <\/em> 1968;116(4):373-380. doi:10.1001\/archpedi.1968.02100020377005 \r\n3.\tAllanson JE, Bohring A, D\u00f6rr HG, et al. The face of Noonan syndrome: Does phenotype predict genotype. Am J Med Genet A. <\/em>2010;152A(8):1960-1966. doi:10.1002\/ajmg.a.33518 \r\n4.\tDerbent M, \u00d6ncel Y, Tokel K, et al. Clinical and hematologic findings in Noonan syndrome patients with PTPN11 gene mutations. Am J Med Genet A. <\/em>2010;152A(11):2768-2774. doi:10.1002\/ajmg.a.33713 \r\n5.\tSinger ST, Hurst D, Addiego JE. Bleeding disorders in Noonan syndrome: Three case reports and review of the literature. Journal of pediatric hematology\/oncology. <\/em>1997;19(2):130-134. doi:10.1097\/00043426-199703000-00006 \r\n6.\tMorice A, Harroche A, Cairet P, Khonsari RH. Preoperative Detailed Coagulation Tests Are Required in Patients With Noonan Syndrome. J Oral Maxillofac Surg. <\/em>2018;76(7):1553-1558. doi:10.1016\/j.joms.2017.12.012 \r\n7.\tWitt DR, McGillivray BC, Allanson JE, et al. Bleeding diathesis in Noonan syndrome: a common association. Am J Med Genet.<\/em> 1988;31(2):305-317. doi:10.1002\/ajmg.1320310208. \r\n8.\tWiegand G, Hofbeck M, Zenker M, Budde U, Rauch R. Bleeding diathesis in Noonan syndrome: is acquired von Willebrand syndrome the clue?. Thromb Res.<\/em> 2012;130(5):e251-e254. doi:10.1016\/j.thromres.2012.08.314\r\n\r\n”,”redirect_url”:””}}}

{“questions”:{“79e15”:{“id”:”79e15″,”mediaType”:”image”,”answerType”:”text”,”imageCredit”:””,”image”:””,”imageId”:””,”video”:””,”imagePlaceholder”:””,”imagePlaceholderId”:””,”title”:”Author: Stephanie Grant, MD \u2013 Emory University and Children\u2019s Healthcare of Atlanta \r\n\r\nA three-week-old female with supravalvular aortic stenosis, peripheral pulmonary artery stenosis, and dysmorphic facial features consistent with an elfin-like face is being evaluated prior to supravalvular aortic stenosis repair. A transthoracic echocardiograph demonstrates narrowing of the aorta at the sinotubular junction with a supravalvular aortic gradient of 90 mmHg and normal coronary arteries. Results of genetic testing are pending. Which of the following electrolyte abnormalities would you MOST LIKELY expect on this patient\u2019s pre-operative labs?”,”desc”:””,”hint”:””,”answers”:{“zmjvj”:{“id”:”zmjvj”,”image”:””,”imageId”:””,”title”:”A. Hypoglycemia “},”wh6hi”:{“id”:”wh6hi”,”image”:””,”imageId”:””,”title”:”B. Hypocalcemia”},”e1ym0″:{“id”:”e1ym0″,”image”:””,”imageId”:””,”title”:”C. Hypercalcemia”,”isCorrect”:”1″},”clo8h”:{“id”:”clo8h”,”image”:””,”imageId”:””,”title”:”D. Hypernatremia”}}}},”results”:{“heel0”:{“id”:”heel0″,”title”:””,”image”:””,”imageId”:””,”min”:”0″,”max”:”1″,”desc”:””,”redirect_url”:”https:\/\/ccasociety.org\/wp-content\/uploads\/2022\/11\/CCAS-QOW-Posted-11-17-2022.pdf”}}}

{“questions”:{“vl96q”:{“id”:”vl96q”,”mediaType”:”image”,”answerType”:”text”,”imageCredit”:””,”image”:””,”imageId”:””,”video”:””,”imagePlaceholder”:””,”imagePlaceholderId”:””,”title”:”Authors: Christopher Busack, MD and Daniela Perez-Velasco, DO \u2013 Children\u2019s National Hospital \r\nA 3-year-old male child with heterotaxy syndrome is scheduled for the Fontan procedure. Which of the following anatomic configurations is MOST LIKELY to be associated with the lowest transplant free survival after the Fontan procedure?”,”desc”:””,”hint”:””,”answers”:{“qq6u5”:{“id”:”qq6u5″,”image”:””,”imageId”:””,”title”:”A. Situs inversus totalis”},”s9de1″:{“id”:”s9de1″,”image”:””,”imageId”:””,”title”:”B. Left isomerism”},”8hv5l”:{“id”:”8hv5l”,”image”:””,”imageId”:””,”title”:”C. Right isomerism”,”isCorrect”:”1″},”vih0e”:{“id”:”vih0e”,”image”:””,”imageId”:””,”title”:”D. Situs solitus\r\n\r\n”}}}},”results”:{“pps2l”:{“id”:”pps2l”,”title”:””,”image”:””,”imageId”:””,”min”:”0″,”max”:”1″,”desc”:””,”redirect_url”:”https:\/\/ccasociety.org\/wp-content\/uploads\/2022\/11\/CCAS-QOW-Posted-11-10-2022.pdf”}}}

{“questions”:{“rayb8”:{“id”:”rayb8″,”mediaType”:”image”,”answerType”:”text”,”imageCredit”:””,”image”:””,”imageId”:””,”video”:””,”imagePlaceholder”:””,”imagePlaceholderId”:””,”title”:”Author: Sana Ullah, MB ChB, FRCA \u2013 Dallas, TX \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”:””,”hint”:””,”answers”:{“n0fvy”:{“id”:”n0fvy”,”image”:””,”imageId”:””,”title”:”A. 1:1″},”jmf93″:{“id”:”jmf93″,”image”:””,”imageId”:””,”title”:”B. 2:1″,”isCorrect”:”1″},”a76xd”:{“id”:”a76xd”,”image”:””,”imageId”:””,”title”:”C. 3:1″},”637mm”:{“id”:”637mm”,”image”:””,”imageId”:””,”title”:”D. Cannot be calculated with the given information”}}}},”results”:{“gtnc6”:{“id”:”gtnc6″,”title”:””,”image”:””,”imageId”:””,”min”:”0″,”max”:”1″,”desc”:””,”redirect_url”:”https:\/\/ccasociety.org\/wp-content\/uploads\/2022\/11\/CASS-QOW-Posted-11-3-2022.pdf”}}}}