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

{“questions”:{“eblde”:{“id”:”eblde”,”mediaType”:”video”,”answerType”:”text”,”imageCredit”:””,”image”:””,”imageId”:””,”video”:”https:\/\/ccasociety.org\/wp-content\/uploads\/2023\/01\/Mid-Esophageal-RV-Inflow-Outflow-with-Color-MP4.mp4″,”imagePlaceholder”:””,”imagePlaceholderId”:””,”title”:”Author: Kevin Spellman, MD; Michael A. Evans, MD; Ann & Robert H. Lurie Children\u2019s Hospital of Chicago, Northwestern Feinberg School of Medicine \r\n\r\nA 5-month-old female infant with a history of congenital pulmonary valve stenosis status post transcatheter pulmonary valvuloplasty presents for surgical pulmonary valve repair due to residual stenosis with a peak gradient of 51 mmHg. In the operating room, a transannular patch is performed in addition to a commissurotomy secondary to the discovery of a bicuspid pulmonary valve with fused and thickened valve leaflets. Following separation from cardiopulmonary bypass, transesophageal echocardiography (TEE) demonstrates free pulmonary insufficiency in addition to the images illustrated below: \r\n\r\nBased on the TEE findings, which of the following is the MOST appropriate course of clinical management? \r\n\r\nImage 1. Deep Transgastric RV Outflow Doppler Across Pulmonary Annulus \r\n \r\n\r\nClip 1. Mid Esophageal RV Inflow Outflow “,”desc”:”EXPLANATION \r\nPulmonary valve stenosis can be present at the valve region (valvar), above the valve (supravalvar), or below the valve (subpulmonary\/infundibular). Pulmonary valvar stenosis is graded based on the transpulmonary gradient, as planimetry is not possible given the available image planes. The pressure gradient is calculated based on the modified Bernoulli equation (\u2206P=4v^{2 <\/sup>), which is dependent on the precision of the doppler measurements. If the ultrasound beam is not parallel to the direction of blood flow, velocity may be underestimated. The severity of pulmonary stenosis may also be graded by utilizing spectral doppler. Pulmonary stenosis is mild if the peak velocity is <3 m\/s and peak gradient is <36 mmHg. Moderate disease consists of a peak velocity of 3-4 m\/s and peak gradient of 36-64 mmHg. Lastly, severe disease consists of a peak velocity >4 m\/s and peak gradient >64 mmHg. \r\n\r\nThe question stem highlights a finding on the postoperative TEE of residual pulmonary valve stenosis. Clip #1 represents a Mid Esophageal RV Inflow Outflow View with the highest velocities measured near the pulmonary valve annulus. Continuous doppler over the pulmonary annulus (Image 1) demonstrates a peak velocity of 41 mmHg, which nearly matches the pre-operative value of 51 mmHg, and indicates that there is significant stenosis present despite surgery. Thus, in a patient who presented with symptomatic, moderate pulmonary stenosis while under general anesthesia (peak gradient of 51 mmHg) and had little improvement after the initial surgical repair (peak gradient of 41 mmHg) as illustrated by echo, the appropriate course of action is to reinitiate bypass and undergo further surgical intervention. \r\n\r\nThe surgeons must take down the transannular patch, and either 1) extend the ventriculotomy incision further into the right ventricular outflow tract or infundibulum thus revising the transannular patch or 2) resect the pulmonary valve. Often, extension of ventriculotomy and patch revision is limited by coronary anatomy. In this case, the question stem states that free pulmonary insufficiency is achieved, which in the setting of residual pulmonary stenosis indicates valve tissue and\/or the small annulus continue to be obstructive. Thus, the correct answer is C, to resect the pulmonary valve. To avoid this complication, many surgeons resect pulmonary valve leaflets with the annular incision prior to sewing in the transannular patch. \r\n\r\nAdministration of protamine (answer A) would not be correct as there is a residual gradient requiring surgical correction. \r\n\r\nThe provided echocardiographic images do not indicate that right ventricular muscle bundles are responsible for residual stenosis (answer B), but rather that an area of stenosis at the level of the pulmonary valve is responsible. \r\n\r\nREFERENCES \r\nBaumgartner H, Hung J, Bermejo J, et al. Echocardiographic assessment of valve stenosis: EAE\/ASE recommendations for clinical practice [published correction appears in Eur J Echocardiogr.<\/em> 2009 May;10(3):479]. Eur J Echocardiogr.<\/em> 2009;10(1):1-25. doi:10.1093\/ejechocard\/jen303\r\n\r\nLinglart L, Gelb BD. Congenital heart defects in Noonan syndrome: Diagnosis, management, and treatment. Am J Med Genet C Semin Med Genet.<\/em> 2020;184(1):73-80. doi:10.1002\/ajmg.c.31765\r\n\r\nRobertson M, Benson LN, Smallhorn JS, et al. The morphology of the right ventricular outflow tract after percutaneous pulmonary valvotomy: long term follow up. Br Heart J. <\/em>1987;58(3):239-244. doi:10.1136\/hrt.58.3.239\r\n\r\nStout KK, Daniels CJ, Aboulhosn JA, et al. 2018 AHA\/ACC Guideline for the Management of Adults With Congenital Heart Disease: Executive Summary: A Report of the American College of Cardiology\/American Heart Association Task Force on Clinical Practice Guidelines [published correction appears in J Am Coll Cardiol<\/em>. 2019 May 14;73(18):2361]. J Am Coll Cardiol. <\/em>2019;73(12):1494-1563. doi:10.1016\/j.jacc.2018.08.1028\r\n\r\nWaller BF, Howard J, Fess S. Pathology of pulmonic valve stenosis and pure regurgitation. Clin Cardiol.<\/em> 1995;18(1):45-50. doi:10.1002\/clc.4960180112\r\n\r\nPuchalski MD, Lui GK, Miller-Hance WC, et al. Guidelines for Performing a Comprehensive Transesophageal Echocardiographic: Examination in Children and All Patients with Congenital Heart Disease: Recommendations from the American Society of Echocardiography [published correction appears in J Am Soc Echocardiogr.<\/em> 2019 May;32(5):681] [published correction appears in J Am Soc Echocardiogr<\/em>. 2019 Oct;32(10):1373-1378]. J Am Soc Echocardiogr.<\/em> 2019;32(2):173-215. doi:10.1016\/j.echo.2018.08.016\r\n\r\n\r\n\r\n”,”hint”:””,”answers”:{“103or”:{“id”:”103or”,”image”:””,”imageId”:””,”title”:”A.)\tAdminister protamine”},”6itp0″:{“id”:”6itp0″,”image”:””,”imageId”:””,”title”:”B.)\tReinitiate cardiopulmonary bypass and resect right ventricular muscle bundles “},”4gn5y”:{“id”:”4gn5y”,”image”:””,”imageId”:””,”title”:”C.)\tReinitiate cardiopulmonary bypass and resect the pulmonary valve”,”isCorrect”:”1″}}}}}}

{“questions”:{“0cquf”:{“id”:”0cquf”,”mediaType”:”image”,”answerType”:”text”,”imageCredit”:””,”image”:””,”imageId”:””,”video”:””,”imagePlaceholder”:””,”imagePlaceholderId”:””,”title”:”Author: Michael A. Evans, MD; Ann & Robert H. Lurie Children\u2019s Hospital of Chicago, Northwestern Feinberg School of Medicine \r\n\r\nA three-year-old female toddler with severe idiopathic pulmonary arterial hypertension presents to the emergency department with two months of worsening lethargy. Routine labs demonstrate a hemoglobin of 8.2 g\/dL. Which of the following medications for the treatment of pulmonary hypertension is MOST LIKELY associated with the observed hemoglobin level?”,”desc”:”EXPLANATION \r\nMacitentan is an orally-active endothelin receptor antagonist (ERA) used in the treatment of pulmonary hypertension. Currently, three oral ERAs are prescribed in children for the treatment of pulmonary hypertension: macitentan, bosentan, and ambrisentan. Currently, the only FDA-approved oral ERA in children is bosentan. A fourth oral endothelin receptor antagonist, sitaxsentan, was withdrawn from the market in 2010 due to several reports of fatal liver injury. \r\n\r\nA meta-analysis of 4894 patients taking macitentan, bosentan, or ambrisentan from 24 randomized trials found that the most common adverse effects of oral ERAs were abnormal liver function, peripheral edema, and anemia. Interestingly, the adverse effects stratified differently by drug type. \r\n\r\n\u2022\tBosentan use poses a statistically significant risk of elevated hepatic enzymes when compared to placebo, whereas macitentan does not demonstrate an increased risk. Ambrisentan significantly decreases the risk of abnormal liver function. \r\n\u2022\tBosentan and ambrisentan have a statistically significant risk of causing peripheral edema when compared to placebo, but there is no increased risk with macitentan. \r\n\u2022\tBosentan and macitentan pose a significantly higher risk of anemia when compared to placebo, but there is no increased risk with ambrisentan.\r\n\r\n\r\nBosentan-induced anemia has generally been mild in clinical trials and has not been associated with a need for discontinuation of the drug. Regardless, the current recommendation for clinical surveillance of anemia in patients on bosentan includes monitoring a hemoglobin level every three months. Macitentan-induced anemia appears to be dose-dependent and may warrant discontinuation of the medication. The mechanism by which oral ERAs cause anemia is not known, but it is suspected that fluid retention yields at least some dilutional anemia. \r\n\r\n\r\nSelexipag is an additional pulmonary hypertension medication that is used off-label in children. It is also associated with anemia. In fact, 8.6% of patients treated with selexipag will experience a decrease in hemoglobin concentration to less than 10 g\/dL during treatment. Selexipag and its metabolite selectively bind the prostacyclin PGI_{2<\/sub> receptor, which promotes pulmonary vasodilation, but also inhibits platelet aggregation. Fortunately, the largest trial to date, the GRIPHON trial, did not demonstrate an increased rate of bleeding in patients with PAH who were taking selexipag. Other side effects of selexipag include headache, jaw pain, and hyperthyroidism. \r\n\r\n\r\nSildenafil is a phosphodiesterase-5 inhibitor (PDE5-I) used in the treatment of pulmonary arterial hypertension in adults. It is often used off-label for the same indication in children. It induces smooth muscle relaxation in the pulmonary arterial bed. Side effects are relatively rare, but include headache, pyrexia, upper respiratory tract infection, vomiting, and diarrhea. Importantly, an increased risk of mortality was observed with increasing doses in children, especially after one to two years of chronic use. In 2012, the FDA revised the drug label for sildenafil to state that the \u201cuse of [sildenafil], particularly chronic use, is not recommended in children.\u201d Later, the FDA clarified that \u201cthis recommendation was not intended to suggest that [sildenafil] should never be used in children.\” It remains a mainstay of therapy in pediatric pulmonary hypertension.\r\n\r\n\r\n\r\nEpoprostenol is a prostanoid-type of pulmonary vasodilator used in the treatment of pulmonary arterial hypertension. Epoprostenol was the first and single drug that demonstrated a decrease in mortality with its use in patients with idiopathic or heritable pulmonary arterial hypertension. In children with higher risk of clinical deterioration, initiation of epoprostenol may be indicated. Epoprostenol acts as a synthetic analog of prostaglandin I2<\/sub> in endothelial cells and has a vasodilatory effect. The drug also has anti-inflammatory, anti-aggregation, and antiproliferative effects as well. The drug is administered in an intravenous formulation, thus complications include catheter-associated infection or thrombosis. Other common side effects include jaw pain, headache, nausea, or diarrhea. Anemia is not associated with epoprostenol use. \r\n\r\n\r\nKnowledge of the specific side effects of pulmonary hypertension medications is quite important, as it is common to treat pulmonary hypertension in children with a combination of medications. This practice may be referred to as \u201ctriple therapy,\u201d when it includes a phosphodiesterase-5 inhibitor, an endothelin receptor antagonist, and a prostanoid. While efficacious, triple therapy poses an increased risk of anemia given adverse effect overlap of the three medication classes. The risk of anemia may be further compounded in the presence of therapy with antiplatelet agents, vitamin K antagonists, or factor Xa inhibitors due to an increased risk of bleeding. \r\n\r\n\r\nOf the answer choices, macitentan is most likely to be associated with anemia. \r\n\r\n\r\n\r\n\r\n\r\n \r\n\r\nREFERENCES \r\n\r\nWei A, Gu Z, Li J, et al. Clinical Adverse Effects of Endothelin Receptor Antagonists: Insights from the Meta-Analysis of 4894 Patients From 24 Randomized Double-Blind Placebo-Controlled Clinical Trials. J Am Heart Assoc.<\/em> 2016;5(11):e003896. Published 2016 Oct 26. doi:10.1161\/JAHA.116.003896 \r\nHumbert M, Segal ES, Kiely DG, et al. Results of European post-marketing surveillance of bosentan in pulmonary hypertension. Eur Respir J.<\/em>2007;30(2):338-344. doi:10.1183\/09031936.00138706 \r\n\r\n\r\nPulido T, Adzerikho I, Channick RN, et al. Macitentan and morbidity and mortality in pulmonary arterial hypertension. N Engl J Med.<\/em> 2013;369(9):809-818. doi:10.1056\/NEJMoa1213917 \r\n\r\n\r\nGabbay E, Fraser J, McNeil K. Review of bosentan in the management of pulmonary arterial hypertension. Vasc Health Risk Manag.<\/em> 2007;3(6):887-900. \r\n\r\n\r\nAversa M, Porter S, Granton J. Comparative safety and tolerability of endothelin receptor antagonists in pulmonary arterial hypertension. Drug Saf.<\/em> 2015;38(5):419-435. doi:10.1007\/s40264-015-0275-y \r\n\r\n\r\nBarst RJ, Ivy DD, Gaitan G, et al. A randomized, double-blind, placebo-controlled, dose-ranging study of oral sildenafil citrate in treatment-naive children with pulmonary arterial hypertension. Circulation.<\/em> 2012;125(2):324-334. doi:10.1161\/CIRCULATIONAHA.110.016667 \r\n\r\n\r\nBarst RJ, Beghetti M, Pulido T, et al. STARTS-2: long-term survival with oral sildenafil monotherapy in treatment-naive pediatric pulmonary arterial hypertension. Circulation.<\/em> 2014;129(19):1914-1923. doi:10.1161\/CIRCULATIONAHA.113.005698 \r\n\r\n\r\nDe A, Shah P, Szmuszkovicz J, et al. A Retrospective Review of Infants Receiving Sildenafil. J Pediatr Pharmacol Ther. <\/em>2018;23(2):100-105. doi:10.5863\/1551-6776-23.2.100 \r\n\r\n\r\nUS Food and Drug Administration. \u201cFDA Drug Safety Communication: FDA clarifies Warning about Pediatric Use of Revatio (sildenafil) for Pulmonary Arterial Hypertension.\u201d Published 03\/31\/2014. Updated 01\/15\/2016. Accessed 1\/1\/2023. URL: https:\/\/www.fda.gov\/drugs\/drug-safety-and-availability\/fda-drug-safety-communication-fda-clarifies-warning-about-pediatric-use-revatio-sildenafil-pulmonary \r\n\r\n\r\nBarst RJ, Rubin LJ, Long WA, et al. A comparison of continuous intravenous epoprostenol (prostacyclin) with conventional therapy for primary pulmonary hypertension. N Engl J Med.<\/em> 1996;334(5):296\u2013301. \r\n\r\n\r\nRopero MJC, Cruz-Utrilla A, Escribano-Subias MP. Epoprostenol for the treatment of pulmonary arterial hypertension. Expert Rev. Clin. Pharmacol.<\/em> 2021; 14(8): 1003-1011. \r\n”,”hint”:””,”answers”:{“xf5zz”:{“id”:”xf5zz”,”image”:””,”imageId”:””,”title”:”A.\tSildenafil”},”c6brh”:{“id”:”c6brh”,”image”:””,”imageId”:””,”title”:”B.\tMacitentan”,”isCorrect”:”1″},”rb1xf”:{“id”:”rb1xf”,”image”:””,”imageId”:””,”title”:”C.\tAmbrisentan”},”ml8bc”:{“id”:”ml8bc”,”image”:””,”imageId”:””,”title”:”D.\tEpoprostenol”}}}}}}

{“questions”:{“8aym9”:{“id”:”8aym9″,”mediaType”:”image”,”answerType”:”text”,”imageCredit”:””,”image”:””,”imageId”:””,”video”:””,”imagePlaceholder”:””,”imagePlaceholderId”:””,”title”:”Author: Michael A. Evans, MD; Ann & Robert H. Lurie Children\u2019s Hospital of Chicago, Northwestern Feinberg School of Medicine \r\nAn 18-year-old male adolescent with a history Hypoplastic Left Heart Syndrome palliated with a fenestrated Fontan and who is anticoagulated with rivaroxaban presents to the emergency department with vomiting and altered consciousness. Computed tomography of the head reveals an intracranial hemorrhage. Which of the following agents is the BEST treatment to inhibit the anticoagulative effect of rivaroxaban?”,”desc”:”EXPLANATION \r\nRivaroxaban is a direct Factor Xa inhibitor that is FDA approved for anticoagulation in children over two years of age after the Fontan operation. The brand name of rivaroxaban is Xarelto\u00ae. It is currently the only direct oral anticoagulant (DOAC) that is FDA approved for this indication in the pediatric patient population. Routine blood tests to monitor anticoagulation and dietary restrictions are not required with the use of rivaroxaban, unlike warfarin anticoagulation. Other direct Factor Xa inhibitors include apixaban, enoxaparin, and edoxaban. \r\n\r\nAndexanet alfa (andexanet) is a reversal agent that neutralizes the anticoagulant effects of both direct and indirect factor Xa inhibitors. Andexanet is a catalytically inactive, recombinant modified human factor Xa protein that binds with high affinity to the active site of factor Xa (FXa) inhibitor thereby preventing FXa inhibitor from binding to Factor Xa and thus antagonizing its anticoagulant effect as assessed by measurement of thrombin generation and anti-factor Xa activity. Andexanet antagonizes the anticoagulant activity of apixaban, rivaroxaban, edoxaban, and enoxaparin. Andexanet was FDA approved in 2018, under its Accelerated Approval Program, for the reversal of life-threatening bleeding or uncontrolled bleeding in patients treated with apixaban or rivaroxaban. In the patient described in the question stem, andexanet administration would rapidly reverse systemic anticoagulation. \r\n\r\nThe side effect profile of andexanet alfa is most notable for venous and arterial thrombotic events. In fact, a 2020 meta-analysis of 16 prospective and retrospective studies enrolling patients treated with specific antidotes (idarucizumab and andexanet alfa) for anticoagulation reversal demonstrated a pooled incidence of 5.5% for thrombotic events. A systematic review of the studies on the safety and efficacy of nonvitamin K oral anticoagulants (NOACs) in adult patients with congenital heart disease (CHD) revealed a low annual incidence of thromboembolic events (0.98%) and major bleeding events (1.74%). Although the most common indication for anticoagulation in the adult patient population with congenital heart disease was atrial fibrillation in this study, the majority of both thromboembolic (3.13%) and hemorrhagic (3.17%) events occurred in patients with the Fontan palliation. \r\n\r\nIdarucizumab is a monoclonal antibody fragment used to reverse the effects of dabigatran, a direct thrombin inhibitor. It binds to dabigatran with 350 times greater affinity than thrombin. Idarucizumab would not be effective in reversing the anticoagulant effects of rivaroxaban in this patient. \r\n\r\nVitamin K is utilized for the reversal of coumadin anticoagulation. It would be expected to significantly lower the international normalized ratio (INR) in a 24 to 48 hour time period. It is not utilized as the sole reversal agent in the setting of a life-threatening hemorrhage due to coumadin anticoagulation but is administered concomitantly with fresh frozen plasma or prothrombin complex concentrates. \r\n\r\nPlatelet transfusion could be indicated in the setting of traumatic intracranial hemorrhage, especially to reverse the effects of antiplatelet medications or in the setting of thrombocytopenia. It would not be the first-line intervention in this patient treated with rivaroxaban. \r\n\r\nIn the setting of an intracranial hemorrhage in a patient treated with rivaroxaban, Andexanet alfa is the best initial treatment option. \r\nREFERENCES \r\nSiegal DM, Curnutte JT, Connolly SJ, et al. Andexanet Alfa for the Reversal of Factor Xa Inhibitor Activity. N Engl J Med. <\/em>2015;373(25):2413-2424. doi:10.1056\/NEJMoa1510991\r\n\r\nConnolly SJ, Crowther M, Eikelboom JW, et al. Full Study Report of Andexanet Alfa for Bleeding Associated with Factor Xa Inhibitors. N Engl J Med.<\/em> 2019;380(14):1326-1335. doi:10.1056\/NEJMoa1814051\r\n\r\nStalikas N, Doundoulakis I, Karagiannidis E, et al. Non-Vitamin K Oral Anticoagulants in Adults with Congenital Heart Disease: A Systematic Review. J Clin Med. <\/em>2020;9(6):1794. Published 2020 Jun 9. doi:10.3390\/jcm9061794\r\n\r\nPollack CV Jr, Reilly PA, Eikelboom J, et al. Idarucizumab for Dabigatran Reversal. N Engl J Med.<\/em> 2015;373(6):511-520. doi:10.1056\/NEJMoa1502000\r\n\r\nRodrigues AO, David C, Ferreira JJ, Pinto FJ, Costa J, Caldeira D. The incidence of thrombotic events with idarucizumab and andexanet alfa: A systematic review and meta-analysis. Thromb Res.<\/em> 2020;196:291-296. doi:10.1016\/j.thromres.2020.09.003\r\n”,”hint”:””,”answers”:{“ldtta”:{“id”:”ldtta”,”image”:””,”imageId”:””,”title”:”A.\tIdarucizumab”},”t7yzm”:{“id”:”t7yzm”,”image”:””,”imageId”:””,”title”:”B.\tAndexanet alfa”,”isCorrect”:”1″},”qs0e9″:{“id”:”qs0e9″,”image”:””,”imageId”:””,”title”:”C.\tVitamin K”},”pb1bd”:{“id”:”pb1bd”,”image”:””,”imageId”:””,”title”:”D.\tPlatelet transfusion”}}}}}

{“questions”:{“0856e”:{“id”:”0856e”,”mediaType”:”image”,”answerType”:”text”,”imageCredit”:””,”image”:””,”imageId”:””,”video”:””,”imagePlaceholder”:””,”imagePlaceholderId”:””,”title”:”Authors: Destiny F. Chau MD, Arkansas Children\u2019s Hospital \/University of Arkansas for Medical Sciences, Little Rock, AR and Meera Gangadharan MD, Childrens Memorial Hermann Hospital\/McGovern Medical School, Houston, TX \r\n\r\nA 7-day-old, 3.5 kg male infant with a history of Transposition of the Great Arteries (TGA) is scheduled for the arterial switch operation. A transthoracic echocardiogram reports situs solitus, levocardia, and {S,D,D} segmental anatomy. Which of the following MOST accurately describes the segmental anatomy {S,D,D}? “,”desc”:”EXPLANATION \r\nThe growth in knowledge surrounding the embryologic basis of cardiac development necessitates a consistent classification system to accurately describe and classify the many variations in cardiovascular defects. Standardization of the cardiac nomenclature and a universally accepted classification system is critical for appropriately diagnosing and disseminating accurate information across professional specialties caring for congenital heart disease (CHD) patients. Unfortunately, at present time, there is not one universally accepted classification system. \r\n\r\nThe sequential segmental approach is a widely accepted diagnostic evaluation of CHD. There are many publications describing this approach to the evaluation and diagnosis of CHD and the steps involved in a structural assessment. The segmental approach was initially described by Van Praagh and colleagues and rests upon an examination of cardiac anatomy in segments. The anatomy of each segment and the relationship of each segment to the others represents the underpinning of segmental analysis. A second system described by Robert Anderson and colleagues added to this concept but minimized the focus on the relationships between segments by using a model based on blood flow through the heart, which focused on characterizing the connections between the segments, termed a sequential segmental approach. In each segment, right and left-sided structures are evaluated based on the morphology, relative orientations, proximal and distal connections, and presence of abnormalities such as shunts and stenosis. Generally, clinicians have been segregated into followers of the Van Praagh or Anderson approach though many medical professionals have opted for a position in the middle. The chosen classification system for use at a particular institution is often based on preference. \r\n\r\n\r\nDefining the thoraco-abdominal organ position and cardiac position\/apex orientation are important components of the cardiac evaluation and should precede the sequential segmental analysis. Embryologically, all major organ systems are initially positioned in the midline and have mirror image symmetry. During normal development, the cardiovascular, respiratory and gastrointestinal systems become asymmetric, referred to as visceral situs solitus.<\/em> Abnormal situs development can result in mirror-image visceral situs (visceral situs inversus)<\/em> or an ambiguous visceral situs (visceral situs ambiguous).<\/em> Mirror image arrangement describes reversed left-right position and orientation of the organs. Situs ambiguous refers to elements of situs solitus and situs inversus in the same patient. \r\n\r\n\r\nCardiac position is often described as the thoracic position where the majority of the cardiac mass is located: levocardia (left-hemithorax), dextrocardia (right-hemithorax) and mesocardia (mid-thorax). Although these prior terms have also been used to describe the base-to-apex orientation, the apex orientation is often, although not always, in agreement to the cardiac position within the chest. Dextrocardia describes the cardiac apex pointing towards the right side of the chest, mesocardia indicates apex pointing inferiorly, and levocardia pointing to the left side of the chest. Displacement of the heart into the right or left thorax should be indicated by the terms dextropositioning or levopositioning, respectively. \r\n\r\n\r\nThe Van Praagh style uses a unique three-letter notation, or code, inside curly brackets such as {X,X,X}. The letters are abbreviations that represent the sidedness or anatomic arrangement (situs) of the three main cardiac segments of the heart in venoarterial sequence (atria, ventricles, and great arteries). A normal heart is coded {S,D,S}. Atrial situs describes the arrangement of the atria as ascertained by the position of the morphologic right and left atria. When the atria are identified, their situs can then be defined. Similarly the same approach is followed for the ventricles. In the Van Praagh shorthand notation, the types of atrial situs are \”S\” for situs solitus <\/em>(normal arrangement), \”I\” for situs inversus <\/em>and \”A\” for situs ambiguous <\/em>(indeterminate arrangement). \r\n\r\n\r\nThe ventricular segment is described by the type of ventricular loop (handedness of the ventricular mass) and the relationship between the atria and ventricles in three-dimensional space. In the normal D-loop (\u201cD\u201d) heart, the ventricles are normally related and the morphologic right ventricle is right-handed relative to morphologic left ventricle which is left-handed. L-looping of the ventricles is also known as inverted ventricles (morphologic right ventricle is left-handed and morphologic left ventricle is right-handed). The types of ventricular situs (loop or topology) per the Van Praagh system include: solitus <\/em>or D-loop ventricles (D), inverted <\/em>or L-loop ventricles (L); and ambiguous or X-loop ventricles (X). \r\n\r\n\r\nThe great arterial situs is described by the spatial relations between great arteries and the semilunar valves (anterior-posterior and right-left position). In patients with normally related great arteries, the main pulmonary artery is anterior to the aorta and then courses leftward. The aorta is posterior to the main pulmonary artery and courses to the right. The pulmonary valve is anterior to and to the left of the aortic valve. The Van Praagh system describes the types of great arterial situs as follows: 1) solitus <\/em>(aortic valve posterior and to the right of the pulmonary valve)- normally related great arteries (S) or D-transposition (aorta is anterior and to the right of the pulmonary trunk); 2) inversus <\/em>(aortic valve to left of the pulmonary valve)- inverted, normally related great arteries (I), or L-transposition\/malposition (L); 3) ambiguous (right-left location of the aortic valve directly anterior to pulmonary valve is neither a right nor left location- A-transposition\/malposition (A). \r\n\r\n\r\nIn this case scenario, this patient is reported to have situs solitus, levocardia, and {S,D,D} segmental anatomy. The Van Praagh segmental system denotes {S,D,D} as \”S\” for situs solitus or normal atrial arrangement, \”D\” for D-looped or normally related ventricles (morphologic right ventricle is right-handed and the morphologic left ventricle is left-handed), and \”D\” for D-malposed or transposed great arteries, with the aorta to the right of the pulmonary trunk rather than posterior to the main pulmonary artery. \r\n\r\nREFERENCES \r\n \r\n\r\nVan Praagh R. Terminology of congenital heart disease. Glossary and commentary. Circulation.<\/em> 1977;56(2):139-143. \r\n\r\n\r\nAnderson RH, Shirali G. Sequential segmental analysis. Ann Pediatr Cardiol. <\/em>2009; 2: 24-35. \r\n\r\n\r\nJacobs JP, Anderson RH, Weinberg PM, et al. The nomenclature, definition and classification of cardiac structures in the setting of heterotaxy. Cardiol Young.<\/em> 2007;17 Suppl 2:1-28. 07001138\r\n\r\n\r\nKussman BD, Miller-Hance WC. Development of the cardiovascular system and nomenclature for congenital heart disease. In: Andropoulos DB, ed. Anesthesia for Congenital Heart Disease. 3rd ed. Hoboken, NJ; Wiley-Blackwell. 2015: 42-82. \r\n\r\n\r\nEdwards WD, Maleszewski JJ. Classification and terminology of cardiovascular anomalies. In: Allen HD, Driscoll DJ, Shaddy RE and Feltes, TF, eds. Moss and Adams’ heart disease in infants, children and adolescents, including the fetus and young adult. 8th ed. Philadelphia, PA; Lippincott Williams & Wilkins. 2013: 32-51.\r\n\r\n”,”hint”:””,”answers”:{“sy3cc”:{“id”:”sy3cc”,”image”:””,”imageId”:””,”title”:”A.\tInverted atria, normally related ventricles, aorta to the right of the pulmonary trunk”},”3vv34″:{“id”:”3vv34″,”image”:””,”imageId”:””,”title”:”B.\tNormal atria, inverted ventricles, aorta to the left of the pulmonary trunk”},”8dxzi”:{“id”:”8dxzi”,”image”:””,”imageId”:””,”title”:”C.\tNormal atria, normally related ventricles, aorta to the right of the pulmonary trunk”,”isCorrect”:”1″},”d2fxj”:{“id”:”d2fxj”,”image”:””,”imageId”:””,”title”:”D.\tInverted atria, indeterminate ventricles, aorta anterior to the pulmonary trunk”}}}}}

{“questions”:{“un5e3”:{“id”:”un5e3″,”mediaType”:”image”,”answerType”:”text”,”imageCredit”:””,”image”:””,”imageId”:””,”video”:””,”imagePlaceholder”:””,”imagePlaceholderId”:””,”title”:”Authors: Destiny F. Chau, MD – Arkansas Children\u2019s Hospital\/University of Arkansas for Medical Sciences, Little Rock, AR and Lawrence Greiten, MD \u2013 Pediatric Cardiothoracic Surgery, Arkansas Children\u2019s Hospital\/University of Arkansas for Medical Sciences, Little Rock, AR \r\n\r\nA 14-month-old, 10 kg male toddler with complex multilevel left ventricular outflow tract obstruction and aortic insufficiency is status post the Ross-Konno procedure during which the perfusionist uses del Nido cardioplegia. Which of the following additives is unique to del Nido cardioplegia?”,”desc”:”EXPLANATION \r\nAdequate myocardial protection during periods of cardiac arrest and myocardial ischemia while on cardiopulmonary bypass (CPB) is of paramount importance for good outcomes after cardiac surgery. Poor myocardial protection can lead to irreversible myocardial damage from ischemia and has been is associated with increased postoperative morbidity and mortality. \r\n\r\nThe principles of myocardial protection center on maximally reducing metabolic rate, supporting aerobic and anaerobic metabolism, preserving intracellular pH, and minimizing intracellular metabolic injury due to sodium, calcium, and oxygen free-radical accumulation. Visible end-points of myocardial protection are mechanical cardiac arrest, lack of electrical activity on the ECG and hypothermic core body temperature. Cardioplegia solutions for myocardial protection have been researched for over 40 years. Currently, there are a number of cardioplegia solutions with variable compositions, ranging from commercial to customized institutional solutions. They can be broadly classified as crystalloid cardioplegia or blood- cardioplegia depending upon the addition of blood to the cardioplegia solution. Additionally, techniques and protocols for the administration of cardioplegia vary widely depending on the patient population, surgical procedure, surgeon preference and institutional factors. Cardioplegia dose is dependent upon the particular cardioplegia formulation and the expected time of myocardial arrest. Limiting the total number and frequency of repeated cardioplegia doses is desired to reduce overall manipulation of the heart, reduce the aortic cross-clamp time and prevent myocardial edema. \r\n\r\n\r\nA common characteristic of cardioplegia solutions is high potassium concentration in order to induce contractile arrest through membrane hyperpolarization. Components such as magnesium, mannitol, sodium bicarbonate, and lidocaine are present in cardioplegia for a number of reasons. Lidocaine is a sodium channel blocker and antiarrhythmic. Sodium channel blockage increases myocyte refractory time. Additionally, sodium channel blockage helps to counteract the negative impact of hyperkalemic arrest by polarizing the cell membrane and preventing intracellular sodium and calcium accumulation. Magnesium is a natural calcium channel blocker and reduces the accumulation of intracellular calcium. Low intracellular calcium concentrations have been associated with reduced myocardial injury. Sodium bicarbonate is a buffer which scavenges excess hydrogen ions and assists with maintaining intracellular pH. Hyperosmotic mannitol scavenges free radicals and reduces myocardial swelling. The addition of red blood cells to cardioplegia has been shown to preserve myocardial metabolism and function, resulting in less metabolic ischemic stress and reperfusion injury when compared to crystalloid-cardioplegia. In addition, red blood cells contain carbonic anhydrase, an enzyme that facilitates the scavenging of hydrogen ions to generate carbon dioxide and water. \r\n\r\n\r\nA survey of the utilization of cardioplegia solutions by congenital cardiac surgical programs in North America found that blood-based cardioplegia formulations are predominantly used by 86% of respondents. Use of the del Nido solution was reported most commonly in 38% of respondents, followed by customized solutions in 32%. \r\n\r\n\r\nOriginally, the same cardioplegia formulations used in adults were also used in pediatric patients. However, in the 1990\u2019s, the del Nido cardioplegia solution was created for myocardial protection of the immature myocardium of neonates and pediatric patients. At the present time, it is increasingly being utilized for myocardial preservation during adult cardiac surgery. \r\n\r\n\r\nAlthough the current del Nido cardioplegia solution has evolved from the original cardioplegia formulations, it is unique in that it contains lidocaine. It contains a base solution of Plasma-Lyte A, with an electrolyte composition resembling extracellular fluid. A one-liter formulation of del Nido cardioplegia includes the following: Plasmalyte-A (1L), magnesium (2 g, 4 mL), potassium chloride (26 mEq, 13 mL), mannitol (3.26 g, 16 mL), sodium bicarbonate (13 mEq, 13 mL) and lidocaine (130 mg, 13 mL). Calcium is not added, although a small amount of calcium is derived from the addition of whole blood. This formulation is deemed to arrest the heart in diastole. The del Nido solution is generally used as a single-dose of 20 mL\/kg. Larger doses may be needed for patients with a thickened myocardium, aortic insufficiency or other conditions where myocardial protection is more challenging. Compared to other formulations, del Nido cardioplegia has been reported to provide comparable myocardial protection, longer cardiac arrest time from a single dose, and lower total volumes of cardioplegia solution with less hemodilution. \r\n\r\n\r\nIt is important for cardiac anesthesiologist to be familiar with cardioplegia solution types used during cardiac surgeries. Multiple dosing with high total volume for complex surgeries leads to hemodilution. Although the accumulation of cardioplegia components such as potassium and lidocaine are usually not clinically significant, awareness and perspective on this information is relevant. \r\nREFERENCES \r\nSinha P. Myocardial Protection. In: Jonas RA, ed. Comprehensive Surgical Management of Congenital Heart Disease.<\/em> 2nd Edition. Boca Raton, Florida: CRC Press, Taylor and Francis Group, LLC; 2014: 214-216. \r\n\r\n\r\nWaterford SD, Ad N. Del Nido cardioplegia: Questions and (some) answers. J Thorac Cardiovasc Surg.<\/em> 2021;S0022-5223(21)01676-7. \r\n\r\n\r\nMatte GS, del Nido PJ. History and use of del Nido cardioplegia solution at Boston Children’s Hospital [published correction appears in J Extra Corpor Technol. 2013 Dec;45(4):262]. J Extra Corpor Technol.<\/em> 2012;44(3):98-103. \r\n\r\n\r\nGinther RM Jr, Gorney R, Forbess JM. Use of del Nido cardioplegia solution and a low-prime recirculating cardioplegia circuit in pediatrics. J Extra Corpor Technol.<\/em> 2013;45(1):46-50. \r\n\r\n\r\nKotani Y, Tweddell J, Gruber P, et al. Current cardioplegia practice in pediatric cardiac surgery: a North American multi-institutional survey. Ann Thorac Surg.<\/em> 2013;96(3):923-929. \r\n\r\n\r\nHaranal M, Chin HC, Sivalingam S, et al. Safety and Effectiveness of Del Nido Cardioplegia in Comparison to Blood-Based St. Thomas Cardioplegia in Congenital Heart Surgeries: A Prospective Randomized Controlled Study. World J Pediatr Congenit Heart Surg.<\/em> 2020;11(6):720-726. \r\n\r\n”,”hint”:””,”answers”:{“9ilh7”:{“id”:”9ilh7″,”image”:””,”imageId”:””,”title”:”A.\tPotassium “},”rliok”:{“id”:”rliok”,”image”:””,”imageId”:””,”title”:”B.\tMagnesium”},”fc7ht”:{“id”:”fc7ht”,”image”:””,”imageId”:””,”title”:”C.\tMannitol”},”pxye6″:{“id”:”pxye6″,”image”:””,”imageId”:””,”title”:”D.\tLidocaine”,”isCorrect”:”1″}}}}}