{“questions”:{“tf7ir”:{“id”:”tf7ir”,”mediaType”:”image”,”answerType”:”text”,”imageCredit”:””,”image”:””,”imageId”:””,”video”:””,”imagePlaceholder”:””,”imagePlaceholderId”:””,”title”:”Authors: Jorge Guerrero, MD and Destiny F Chau, MD Arkansas Children\u2019s Hospital\/University of Arkansas for Medical Sciences, Little Rock, AR
\r\n\r\nA five-year-old female child with a history of Williams-Beuren syndrome and mild supravalvar pulmonary stenosis is undergoing a diagnostic colonoscopy for abdominal pain. After an uneventful intraprocedural course with stable hemodynamics, ondansetron and acetaminophen are administered prior to emergence of anesthesia. Within a few minutes the electrocardiogram (ECG) shows torsades de pointes. The MOST LIKELY trigger for this arrhythmia is:\r\n”,”desc”:””,”hint”:””,”answers”:{“xrsh7”:{“id”:”xrsh7″,”image”:””,”imageId”:””,”title”:”A)\tLight anesthesia”},”v606t”:{“id”:”v606t”,”image”:””,”imageId”:””,”title”:”B)\tVenous air embolism”},”z1s56″:{“id”:”z1s56″,”image”:””,”imageId”:””,”title”:”C)\tOndansetron administration”,”isCorrect”:”1″},”h6mju”:{“id”:”h6mju”,”image”:””,”imageId”:””,”title”:”D)\tAcetaminophen administration”}}}},”results”:{“bwn36”:{“id”:”bwn36″,”title”:””,”image”:””,”imageId”:””,”min”:”0″,”max”:”1″,”desc”:”Williams or Williams-Beuren syndrome (WBS) is a genetic disease that affects 1: 8000-10,000 individuals. The syndrome has been linked to deletions of 1.5 to 1.8 base pairs on chromosome 7q11.25, which encompass the elastin gene (ELN). The cardiovascular findings associated with WBS are due to the lack of elastin production as a consequence of this gene deletion. Eighty percent of patients with WBS have cardiovascular manifestations, which include supravalvular aortic stenosis and pulmonary artery stenosis – typically the branch pulmonary arteries. Forty-five percent of patients with supravalvular aortic stenosis will also have coronary anomalies. Any artery may be involved, including the mid- thoracic aorta, renal arteries, carotid arteries, and cerebral arteries.
\r\n\r\nUp to 14% of WBS patients will have a prolonged QTc\/JTc interval. This may be a contributing factor to a higher-than-normal incidence of adverse cardiac events related to WBS. Many patients with WBS exhibit increased prolongation of the QTc during periods of increased heart rate, which also occurs in patients with microvascular cardiac disease. The occurrence of ectopic beats may also suggest ischemia. However, a concurrent channelopathy due to the genetic deletion cannot be excluded. In a retrospective study by McCarty et al, patients with supravalvular aortic stenosis but without WBS were compared to patients with supravalvular aortic stenosis and WBS. The results demonstrated that the QTc was significantly prolonged in patients with WBS independent of the degree of myocardial hypertrophy as compared to patients without WBS. Additionally, patients with WBS whom underwent repair of obstructive outflow lesions did not show a regression of the prolonged QTc, which presumably would resolve in patients with supravalvular aortic obstruction without WBS. Further studies are needed to elucidate the etiology of the prolonged QTc (ie the role of channelopathies, microvascular abnormalities and related ischemia, or a combination of both). In general, a prolonged QTc can be an isolated finding or it can occur in the setting of cardiac structural lesions. A prolonged QTc can lead to torsades de pointes and may degrade to ventricular fibrillation. It is prudent to avoid drugs that prolong QTc especially if QTc prolongation is already present. Many medications used for anesthesia and sedation, including the potent inhaled anesthetics, can prolong QTc.
\r\n\r\n\r\nOther features associated with WBS include a \u201ccocktail-like\u201d personality, high degree of anxiety, attention deficit hyperactivity disorder, and aversion to loud noises. Patients with WBS have intelligence quotients around 50-60. Facial characteristics include a broad forehead, stellate iris, wide nasal bridge, upward pointing nose, large mouth with thick lips, periorbital thickness, and pointed chin. Patients with WBS may exhibit hypercalcemia early in life as well as subclinical hypothyroidism and may develop glucose intolerance progressing to diabetes mellitus in adulthood. They also have a propensity for colic as infants, chronic otitis media, poor dentition and scoliosis. The underlying pathophysiology of WBS predisposes these patients to require more medical attention and undergo more procedures than the general population. Additionally, they are 25-100 times more likely to have an adverse cardiovascular event than the general population. A great majority of events occur when receiving sedation or general anesthesia. Factors that increase the risk of adverse cardiac events are greater severity of supravalvular aortic stenosis (gradient >40 mm Hg), bilateral ventricular outflow obstructive lesions, coronary artery involvement, and a prolonged QTc of 460 ms or greater. Many of the adverse cardiovascular events seem to be related to imbalances in the myocardial oxygen supply and demand related to the vasodilatory and tachycardic effects of anesthetic agents. However, not all of the adverse cardiovascular events can be attributed to ischemia as the sole cause.
\r\n\r\n\r\nOf the choices given in this scenario, ondansetron is the most likely trigger for torsades de pointes. It is known to prolong the QTc. In the setting of an uneventful intraoperative course and stable hemodynamics, the timing of ondansetron administration and subsequent presentation of torsades de pointes suggests that this patient with WBS had an abnormal prolonged QTc which was worsened by the ondansetron. Light anesthesia, venous air embolism, and acetaminophen are unlikely causes for torsades de pointes.
\r\n\r\n\r\nReferences:
\r\n\r\n\r\nStaudt GE, Eagle SS. Anesthetic considerations for patients with Williams syndrome. J Cardiothorac Vasc Anesth<\/em>. 2021; 35(1): 176-186.
\r\n\r\n\r\nCollins RT, Collins MG, Schmitz ML, Hamrick JT. Peri-procedural risk stratification and management of patients with Williams syndrome. Congenit Heart Dis<\/em>. 2017; 12(2): 133-142.
\r\n\r\n\r\nPober BR. Williams-Beuren syndrome. N Engl J Med<\/em>. 2010; 362(3): 239-252.
\r\n\r\n\r\nMcCarty HM, Tang X, Swearingen CJ, Collins RT 2nd. Comparison of electrocardiographic QTc duration in patients with supravalvar aortic stenosis with versus without Williams syndrome. Am J Cardiol<\/em>. 2013; 111(10): 1501-1504.
\r\n\r\n\r\nCollins RT 2nd, Aziz PF, Swearingen CJ, Kaplan PB. Relation of ventricular ectopic complexes to QTc interval on ambulatory electrocardiograms in Williams syndrome. Am J Cardiol<\/em>. 2012; 109(11): 1671-1676.
\r\n\r\n\r\nCollins RT 2nd, Aziz PF, Gleason MM, Kaplan PB, Shah MJ. Abnormalities of cardiac repolarization in Williams syndrome. Am J Cardiol<\/em>. 2010; 106(7): 1029-1033. \r\n\r\n\r\n\r\n”,”redirect_url”:””}}}
Question of the Week 348
{“questions”:{“zj75s”:{“id”:”zj75s”,”mediaType”:”image”,”answerType”:”text”,”imageCredit”:””,”image”:””,”imageId”:””,”video”:””,”imagePlaceholder”:””,”imagePlaceholderId”:””,”title”:”Authors: Gokul Thimmarayan, MD – Marshfield Clinic, Marshfield, WI and\r\nDestiny F Chau, MD – Arkansas Children\u2019s Hospital\/University of Arkansas for Medical Sciences, Little Rock, AR.
\r\n\r\nA 1-day-old neonate with congenital complete heart block is scheduled for a pacemaker placement. Echocardiographic findings reveal a structurally normal heart. What is the MOST COMMON cause of isolated congenital complete heart block?”,”desc”:””,”hint”:””,”answers”:{“wlk9w”:{“id”:”wlk9w”,”image”:””,”imageId”:””,”title”:”A) Maternal metabolic disease”},”tbhj2″:{“id”:”tbhj2″,”image”:””,”imageId”:””,”title”:”B) Maternal autoimmune antibodies”,”isCorrect”:”1″},”eck2s”:{“id”:”eck2s”,”image”:””,”imageId”:””,”title”:”C) Maternal medication exposure during pregnancy”},”s3ht8″:{“id”:”s3ht8″,”image”:””,”imageId”:””,”title”:”D) Maternal viral infection during pregnancy”}}}},”results”:{“7zkfx”:{“id”:”7zkfx”,”title”:””,”image”:””,”imageId”:””,”min”:”0″,”max”:”1″,”desc”:”Congenital complete heart block (CCHB) is a rare disorder that is associated with high morbidity and mortality occurring in approximately 1:15-20,000 patients. CCHB describes atrioventricular block diagnosed in utero or during the first 27 days of life. Of the patients with CCHB, fourteen to forty-two percent of cases are associated with congenital heart disease (CHD). This may include congenitally corrected transposition of the great arteries, complete atrioventricular canal defect, and heterotaxy with left atrial isomerism. Maternal autoimmune antibody transfer is the most common cause (ninety-one percent) of CCHB in the remaining percentage of cases. Maternal factors like diabetes, medication exposure (anticonvulsants and retinoic acid), viral infections, and channelopathies are also associated with increased risk of CCHB in the offspring.
\r\n\r\nAutoimmune CCHB is a manifestation arising from neonatal lupus. Passively transferred maternal autoantibodies to the ribonuclear protein RO (SS-A) and LA (SS-B) cause neonatal lupus. Women with positive antibody titers carry approximately a two percent risk of having a baby with neonatal cardiac lupus after a prior unaffected pregnancy and have a thirteen to eighteen percent risk in subsequent pregnancies. The autoantibodies bind to the cardiac conduction tissue causing inflammation and fibrosis leading to conduction defects. The antibodies are also postulated to affect myocardial cells resulting in cardiomyopathy and endocardial fibroelastosis. Slow heart rate in the fetus with no structural anomaly of the heart and positive maternal antibody is diagnostic of autoimmune CCHB. The vast majority of infants present with third-degree or complete heart block although the presentation may vary from first- to third- degree atrioventricular block. Autoimmune CCHB has an approximate mortality rate of nineteen percent in which a majority occur in utero. Risk of fetal mortality is increased with hydrops, diagnosis of CCHB at earlier than twenty weeks of gestation, ventricular escape rate less than fifty-five beats per minute , impaired left ventricular function, myocardial inflammation, and dilated cardiomyopathy. The presence of dilated cardiomyopathy is a poor prognostic factor. Noncardiac manifestations of neonatal lupus typically self-resolve with clearance of the maternal autoantibodies over the first months of life.
\r\n\r\nFetal echocardiography with doppler is the standard diagnostic tool in evaluating CCHB. The assessment of cardiac anatomy, heart rate and mechanical function can deduce abnormalities of electrophysiologic conduction and cardiac structure. With early diagnosis, subsequent intervention is based on the severity of the heart block along with close follow-up and monitoring with serial fetal echocardiograms. Maternal corticosteroids, intravenous immunoglobulin therapy, beta-agonist therapy, and hydroxychloroquine have been used with varying degrees of success. Once CCHB occurs, it is mostly likely irreversible, necessitating pace-maker implantation. In fact, more than two-thirds of these patients require a permanent pacemaker, the majority of which are implanted in the neonatal period.
\r\n\r\nReferences:
\r\nSteinberg L. Congenital heart block. Card Electrophysiol Clin<\/em>. 2021; 13(4): 691-702.
\r\n\r\nPruetz JD, Miller JC, Loeb GE, Silka MJ, Bar-Cohen Y, Chmait RH. Prenatal diagnosis and management of congenital complete heart block. Birth Defects Res<\/em>. 2019; 111(8): 380-388.
\r\n\r\nFriedman DM, Duncanson LJ, Glickstein J, Buyon JP. A review of congenital heart block. Images Paediatr Cardiol<\/em> 2003; 5(3): 36-48.
\r\n\r\nIzmirly PM, Chalumeau CN, Pisoni C, et al. Maternal use of hydroxychloroquine is associated with a reduced risk of recurrent Anti-SSA\/RO associated cardiac manifestation of neonatal lupus. Circulation<\/em>. 2012; 126(1): 76-82.\r\n”,”redirect_url”:””}}}
Question of the Week 347
{“questions”:{“hc55h”:{“id”:”hc55h”,”mediaType”:”image”,”answerType”:”text”,”imageCredit”:””,”image”:””,”imageId”:””,”video”:””,”imagePlaceholder”:””,”imagePlaceholderId”:””,”title”:”Authors: Gokul Thimmarayan, MD – Marshfield Clinic, Marshfield, WI and\r\nDestiny F. Chau, MD – Arkansas Children\u2019s Hospital\/University of Arkansas for Medical Sciences, Little Rock, AR.
\r\n\r\nA 1-week-old neonate with pulmonary atresia and ventricular septal defect undergoes a complete surgical repair. Postoperatively, the patient has persistent hypocalcemia and prolonged mechanical ventilation due to pneumonia. Subsequent workup demonstrates immunodeficiency. Which of the following syndromes is MOST LIKELY associated with this constellation of findings?\r\n”,”desc”:””,”hint”:””,”answers”:{“8gytg”:{“id”:”8gytg”,”image”:””,”imageId”:””,”title”:”A) 22q11.2 deletion syndrome”,”isCorrect”:”1″},”6n0bu”:{“id”:”6n0bu”,”image”:””,”imageId”:””,”title”:” B) CHARGE syndrome”},”qc38e”:{“id”:”qc38e”,”image”:””,”imageId”:””,”title”:”C) Williams syndrome”},”aj4h6″:{“id”:”aj4h6″,”image”:””,”imageId”:””,”title”:”D) Alagille syndrome”}}}},”results”:{“s50zx”:{“id”:”s50zx”,”title”:””,”image”:””,”imageId”:””,”min”:”0″,”max”:”1″,”desc”:”22q11.2 deletion syndrome is the most common chromosomal microdeletion disorder affecting 1:2000 to 1:6000 live births. The microdeletion leads to the maldevelopment of structures derived from the third and fourth pharyngeal arches. It is associated with parathyroid aplasia or hypoplasia resulting in hypocalcemia; hypoplasia of the thymus leading to immunodeficiency; and conotruncal anomalies such as tetralogy of Fallot, pulmonary atresia with ventricular septal defect, truncus arteriosus, interrupted aortic arch, and ventricular septal defect. It is also associated with palatal anomalies, facial dysmorphism, renal anomalies, speech and learning disabilities, and psychiatric illness. 22q11.2 deletion syndrome is a multisystem disorder with a heterogeneous presentation also known as DiGeorge syndrome, Velocardiofacial syndrome, and Conotruncal anomaly face syndrome.
\r\n\r\nCongenital heart disease (CHD) is the most common cause of mortality in 22q11.2 deletion syndrome. Patients often require multiple cardiac surgeries due to complex congenital heart disease. The postoperative course may be complicated by prolonged mechanical ventilation, inotropic support, and prolonged intensive care unit and hospital stays. Hypocalcemia from parathyroid hypoplasia can be associated with perioperative hemodynamic instability and postoperative seizures. The incidence of hypocalcemia is higher in those patients with CHD than those without CHD. Thymic hypoplasia is associated with T-cell deficiency resulting in an increased risk of recurrent and severe infections. Immunoglobulin (IgG, IgM, IgA) deficiency is seen in 10% of the patients with 22q11.2 deletion syndrome. Transfusion of blood products in IgA deficient patients could lead to a severe anaphylactic reaction. Irradiated and leukocyte-depleted blood products should be used to reduce the risk of infection and prevent transfusion-associated graft vs host disease due to the immunodeficient state. Craniofacial abnormalities such as micrognathia, retrognathia, and cleft palate could cause difficulty during endotracheal intubation. Of the syndromes listed in the answer choices, this patient\u2019s findings of a conotruncal cardiac lesion, persistent hypocalcemia, and immunodeficiency are most consistent with 22q11.2 deletion syndrome. The other syndromes are briefly described below.
\r\nCHARGE syndrome is an acronym for the multisystem genetic conditions: Coloboma, Heart defects, Atresia of choanae, Retardation of growth and mental development, Genitourinary anomalies and Ear malformations\/hearing loss. It occurs with an approximate frequency of 1:10,000 births. It is diagnosed clinically and confirmed by detection of a genetic mutation in the CHD7 gene on chromosome 8q12. Cardiac malformations are present in 75-85% of the patients. Conotruncal defects, atrioventriculoseptal defects, and aortic arch abnormalities are seen commonly in CHARGE syndrome.
\r\nWilliams syndrome or Williams-Beuren syndrome (WS) is a multisystem disorder caused by the deletion of multiple genes in chromosome 7 including the elastin gene. Williams syndrome occurs in 1:7,500 to 10,000 births. Patients with WS have characteristic facial findings including flat nasal bridge, short upturned nose, periorbital puffiness, long philtrum and delicate chin. Smooth muscle cells in patients with WS produce a decreased amount of normal elastin resulting in an arterial media with many hypertrophied smooth muscle cells, thickening of the media of large arteries, and ultimately obstructive lesions. The most common lesion is supravalvular aortic stenosis that characteristically develops at the sinotubular junction. Stenosis can also occur in the pulmonary arteries, coronary arteries, aortic arch, descending aorta, renal arteries, and mesenteric arteries. Patients with Williams syndrome are known to have increased risk of sudden cardiac death, especially in the setting of sedation and anesthesia. This is mostly attributed to the presence of coronary artery stenosis and biventricular outflow tract obstruction. Hypertension, hypercalcemia, impaired growth and impaired cognition are other associated findings.
\r\n\r\nAlagille syndrome is a rare autosomal dominant, multisystem disorder occurring in approximately 1:70,000 births. It is related to mutations in the JAG1 gene or the NOTCH2 gene. It is associated with a paucity of intrahepatic bile ducts leading to cholestasis and potential liver failure. Other abnormalities include cardiac anomalies such as peripheral pulmonary artery stenosis and tetralogy of Fallot; butterfly vertebrae; typical facial features such as prominent forehead, deep-set eyes with moderate hypertelorism, pointed chin, and straight nose with a bulbous tip; and vascular and renal anomalies.
\r\n\r\nReferences:
\r\nYeoh TY, Scavonetto F, Hamlin RJ, Burkhart HM, Sprung J, Weingarten TN. Perioperative management of patients with DiGeorge syndrome undergoing cardiac surgery. J Cardiothorac Vasc Anesth.<\/em> 2014; 28(4): 983-989.
\r\n\r\nRayannavar A, Levitt Katz LE, Crowley TB, et al. Association of hypocalcemia with congenital heart disease in 22q11.2 deletion syndrome. Am J Med Genet A.<\/em> 2018; 176(10): 2099-2103.
\r\n\r\nDavies EG. Immunodeficiency in DiGeorge Syndrome and Options for Treating Cases with Complete Athymia. Front Immunol.<\/em> 2013; 4: 322.
\r\n\r\nNational Institute of Health. National Center for Advancing Translational Sciences. Genetic and Rare diseases Information Center. 22q11.2 deletion syndrome. Last updated 2017 https:\/\/rarediseases.info.nih.gov\/diseases\/10299\/22q112-deletion-syndrome Accessed October 25, 2021.
\r\n\r\nHsu P, Ma A, Wilson M, et al. CHARGE syndrome: a review. J Paediatr Child Health.<\/em> 2014; 50(7): 504-511.
\r\n\r\nPober BR. Williams-Beuren syndrome. N Engl J Med.<\/em> 2010; 362(3): 239-252.
\r\n\r\nBurch TM, McGowan FX, Kussman, BD, Powell AJ, DiNardo JA. Congenital Supravalvar Aortic Stenosis and Sudden Death Associated with Anesthesia: What\u2019s the Mystery? Anesth Analg. 2008;107(6); 1848-1854.
\r\n\r\nCollins Ii RT, Collins MG, Schmitz ML, Hamrick JT. Peri-procedural risk stratification and management of patients with Williams syndrome. Congenit Heart Dis.<\/em> 2017; 12(2): 133.
\r\n\r\nSaleh M, Kamath BM, Chitayat D. Alagille syndrome: clinical perspectives. Appl Clin Genet.<\/em> 2016; 9: 75-82.
\r\n\r\n\r\n”,”redirect_url”:””}}}
Question of the Week 346
{“questions”:{“02yzs”:{“id”:”02yzs”,”mediaType”:”image”,”answerType”:”text”,”imageCredit”:””,”image”:””,”imageId”:””,”video”:””,”imagePlaceholder”:””,”imagePlaceholderId”:””,”title”:”Author: Anna Hartzog MD and Chinwe Unegbu MD \u2013 Children\u2019s National Hospital
\r\n\r\nA 2-month-old infant with dilated cardiomyopathy presents for Left Ventricular Assist Device (LVAD) insertion. The surgeon implants a Levitronix CentriMag pump with Berlin Heart Excor cannulas. What is the MOST LIKELY benefit of initial placement of the CentriMag pump over initial insertion of the complete Berlin Excor system? \r\n\r\n”,”desc”:””,”hint”:””,”answers”:{“7nnsc”:{“id”:”7nnsc”,”image”:””,”imageId”:””,”title”:”A. Anticipated need for long-term VAD support”},”ljm8f”:{“id”:”ljm8f”,”image”:””,”imageId”:””,”title”:”B. No anticoagulation needed with the CentriMag pump “},”gxo1n”:{“id”:”gxo1n”,”image”:””,”imageId”:””,”title”:”C. Reduced hospital costs in the immediate perioperative period”,”isCorrect”:”1″},”g9xok”:{“id”:”g9xok”,”image”:””,”imageId”:””,”title”:”D. Improved chances of myocardial recovery “}}}},”results”:{“j3qmg”:{“id”:”j3qmg”,”title”:””,”image”:””,”imageId”:””,”min”:”0″,”max”:”1″,”desc”:”Approximately 20% to 30% of pediatric patients awaiting heart transplantation are bridged with a Ventricular Assist Device (VAD). This has resulted in a 50% reduction in the waitlist mortality. Candidacy for VAD implantation is often determined by serial monitoring for end-organ dysfunction (ie hepatic, renal, gastrointestinal dysfunction), nutritional status, level of inotropic support, and degree of respiratory compromise. Generally, VAD therapy should occur prior to the onset of severe end-organ dysfunction as this is an independent risk factor of mortality.\r\n
\r\n\r\nSmall children and infants have limited device options. The majority of children who require a VAD are supported with either a pulsatile paracorporeal device or a continuous flow intracorporeal device. The Berlin Heart Excor VAD (Berlin Heart GmbH, Berlin, Germany) is a pulsatile paracorporeal device that is situated externally. The main continuous flow intracorporeal devices are the HeartWare HVAD (Medtronic, Minneapolis, MN) and the HeartMate 3 (Abbott Corporation, Abbott Park, IL) which have pumps that are implanted internally. The HeartWare HVAD and HeartMate 3 are currently US Food and Drug Administration-approved for the therapy of advanced heart failure in adults. However, both devices have been safely and successfully used in patients as small as twenty kilograms and body surface area of 0.6 m2<\/sup>. Continuous flow VADs have a 92% survival rate at 6 months, which is superior to the survival rates in pediatric patients with pulsatile devices.\r\n
\r\n\r\nThe Berlin Heart Excor VAD is a pneumatically-driven, pulsatile pump with a fixed volume chamber ranging from 10 to 80 milliliters. During systole the pump moves compressed air into the pneumatic chamber causing ejection. In diastole negative pressure is applied to the pneumatic chamber to aid filling. Cardiac output is dependent on the size of the chamber and the pump rate. Unfortunately, complications such as stroke, bleeding, and infection are more common with the Berlin Heart EXCOR in comparison to continuous flow devices. \r\n
\r\n\r\nIn addition to durable long-term VADs, temporary or short-term VADs also exist. Temporary circulatory support devices are traditionally defined as those providing support for two to four weeks as a \u201cbridge to recovery\u201d or \u201cbridge to decision\u201d in patients with an acute process. Temporary circulatory support devices now account for 19% of VAD implants. In 2018 Lorts et al used data from the Pediatric Interagency Registry for Mechanical Circulatory Support (PediMACS) to investigate outcomes in patients temporarily supported by VADs. The authors found that 71% had a positive outcome (ie bridge to recovery, bridge to transplant, bridge to a durable device, or alive with a device). Additionally, the authors also discovered that \u201ctemporary\u201d devices were utilized for a wide variety of indications and for durations of time greater than six weeks.\r\n
\r\n\r\nThe CentriMag\/PediMag (Levitronix LLC, Waltham, MA) is a third generation paracorporeal continuous flow device that is being used with increasing frequency for temporary circulatory support. The CentriMag is driven with a bearingless motor, enabling the spinning component within the pump to be magnetically levitated and rotated without contact or wear. By eliminating the bearings, shafts, and seals associated with a conventional centrifugal pump, the incidence of thrombus accumulation and the degree of hemolysis are greatly reduced, which decreases the risk of adverse events. As there is low risk of thromboembolic events, many centers use minimal anticoagulation. This is advantageous after VAD implantation as a significant percentage of patients require re-exploration due to bleeding. In contrast, the Berlin Heart Excor system requires early initiation of anticoagulation therapy. \r\n
\r\n\r\nThe need for minimal anticoagulation and lower hospital-related costs have made the CentriMag pump in combination with the Berlin Heart Excor cannulas a logical choice in some centers. This combination allows the CentriMag pump to stabilize the patient over a period of several weeks. Then once stabilized, the Berlin Heart Excor pump and drive unit can replace the CentriMag. The pump exchange can be accomplished in one to two minutes. The CentriMag pump is less expensive with a cost of $10,000 to $13,000 per pump. In comparison, the Berlin Heart Excor pump costs $39,000 and the driver monthly rental is approximately $10,000. Immediately following VAD implantation, there is considerable inflammation leading to fibrin and clot build up that may necessitate several pump exchanges. Pump exchange is quite expensive, especially with use of the Berlin Excor system. The combined use of both systems can be viewed as a cost effective \u201cbridge to a bridge\u201d.\r\n
\r\n\r\nChoice C is the correct answer as perioperative costs are reduced with the CentriMag. Choice A, B and D are incorrect as the Centrimag is not intended for long-term support, requires some form of anticoagulation, and is not associated with improved myocardial recovery.\r\n
\r\n\r\nReferences
\r\n\r\n1.\tNavaratnam M, Maeda K, Hollander SA. Pediatric ventricular assist devices: Bridge to a new era of perioperative care. Pediatric Anesthesia<\/em>. 2019; 29: 506\u2013518. doi:10.1111\/pan.13609.
\r\n\r\n\r\n2.\tVanderPluym CJ, Adachi I, Niebler R, et al. Outcomes of children supported with an intracorporeal continuous-flow left ventricular assist system. J Heart Lung Transplant<\/em>. 2019; 38(4): 385-393.
\r\n\r\n3.\tChatterjee A, Feldmann C, Hanke JS, et al. The momentum of HeartMate 3: a novel active magnetically levitated centrifugal left ventricular assist device (LVAD). J Thorac Dis<\/em>. 2018; 10(Suppl 15): S1790-S1793.
\r\n\r\n4.\tO\u2019Connor MJ, Lorts A, Davies RR, et al. Early experience with the HeartMate 3 continuous flow ventricular assist device in pediatric patients and patients with congenital heart disease: A multicenter registry analysis. J Heart Lung Transplant<\/em>. 2020; 39: 573-579.
\r\n\r\n5.\tAlmond CS, Morales DL, Blackstone EH, et al. Berlin heart EXCOR pediatric ventricular assist device for bridge to heart transplantation in US children. Circulation<\/em>. 2013; 127: 1702\u20101711. doi: 10.1161\/CIRCULATIONAHA.112.000685.
\r\n\r\n6.\tBlume ED, VanderPluym C, Lorts A, et al. Second annual Pediatric Interagency Registry for Mechanical Circulatory Support (Pedimacs) report: Pre\u2010implant characteristics and outcomes. J Heart Lung Transplant<\/em>. 2018; 37(1): 38\u201045. doi: 10.1016\/j.healun.2017.06.017.
\r\n\r\n\r\n7.\tLorts A, Eghtesady P, Mehegan M, et al. Outcomes of children supported with devices labeled as \u201ctemporary\u201d or short term: A report from the Pediatric Interagency Registry For Mechanical Circulatory Support. J Heart Lung Transplant<\/em>. 2018; 37(1): 54\u201060. doi:10.1016\/j.healun.2017.10.023.
\r\n\r\n8.\tStiller B, Lemmer J, Schubert S, et al. Management of pediatric patients after implantation of the Berlin Heart EXCOR ventricular assist device. ASAIO J<\/em>. 2006; 52(5): 497-500. PMID: 16966844.
\r\n\r\n\r\n9.\tDe Rita F, Hasan A, Haynes S, et al. Outcome of mechanical cardiac support in children using more than one modality as a bridge to heart transplantation. Eur J Cardiothorac Surg<\/em>. 2015; 48: 917-922. doi:10.1093\/ejcts\/ezu544.
\r\n\r\n10.\tConway J, Al-Aklabi M, Granoski D, et al. Supporting pediatric patients with short-term continuous-flow devices. J Heart Lung Transplant<\/em>. 2016; 35: 603-609. doi:10.1016\/j.healun.2016.01.1224.
\r\n\r\n11.\tMaat A.P, van Thiel R.J, Dalinqhaus M, Bogers A.J. Connecting the CentriMag Levitronix pump to Berlin Heart Excor cannula. J Heart Lung Transplant<\/em>. 2008; 27: 112-115. doi: 10.1016\/j.healun.2007.10.010
\r\n\r\n\r\n12.\t Loforte A, Potapov E, Krabatsch T, et al. Levitronix CentriMag to Berlin Heart Excor: A \u201cBridge to Bridge\u201d Solution in Refractory Cardiogenic Shock. ASAIO J<\/em>. 2009; 55(5): 465-468. doi: 10.1097\/MAT.0b013e3181b58c50
\r\n\r\n13.\tJohn R, Long J, Massey T, et al. Outcomes of a multicenter trial of the Levitronix CentriMag ventricular assist system for short-term circulatory support. Mechanical Circulatory Support<\/em>. 2008; 27(1): 112-115. doi:https:\/\/doi.org\/10.1016\/j.jtcvs.2010.03.046
\r\n\r\n\r\n”,”redirect_url”:””}}}
Question of the Week 345
{“questions”:{“yv9hs”:{“id”:”yv9hs”,”mediaType”:”image”,”answerType”:”text”,”imageCredit”:””,”image”:””,”imageId”:””,”video”:””,”imagePlaceholder”:””,”imagePlaceholderId”:””,”title”:”Authors: Anna Hartzog MD and Chinwe Unegbu MD \u2013 Children\u2019s National Hospital
\r\n\r\nA 1-day old neonate with critical aortic stenosis and decreased left ventricular function is intubated due to respiratory failure, pulmonary edema and increasing left atrial pressures. The patient presents to the operating room for surgical repair. What is the GREATEST benefit of a surgical aortic valve repair over aortic balloon valvuloplasty? \r\n”,”desc”:””,”hint”:””,”answers”:{“m2h7l”:{“id”:”m2h7l”,”image”:””,”imageId”:””,”title”:”A. Decreased rate of aortic valve replacement”},”olcn2″:{“id”:”olcn2″,”image”:””,”imageId”:””,”title”:”B. Increased survival rate”},”vt433″:{“id”:”vt433″,”image”:””,”imageId”:””,”title”:”C. Decreased long-term aortic insufficiency “,”isCorrect”:”1″},”8eogh”:{“id”:”8eogh”,”image”:””,”imageId”:””,”title”:”D. Decreased length of hospital stay”}}}},”results”:{“wqsr7”:{“id”:”wqsr7″,”title”:””,”image”:””,”imageId”:””,”min”:”0″,”max”:”1″,”desc”:”Congenital aortic stenosis occurs in approximately 6% of patients with congenital heart disease. While valvar aortic stenosis is most common, stenosis can occur at the subvalvar, valvar, or supravalvar level. Valvar aortic stenosis is more common in males, and is often associated with a bicuspid aortic valve, coarctation of the aorta, patent ductus arteriosus, and ventricular septal defect. Unicuspid aortic valve is most often associated with critical aortic stenosis. If not recognized early, neonates with severe aortic stenosis can present with congestive heart failure, arrhythmias, lactic acidosis, cardiogenic shock, and even sudden death.
\r\n\r\nThe size and function of the left ventricle is the main determinant for appropriateness of a single-ventricle versus a biventricular repair. Measurements that predict a favorable two-ventricle repair include aortic annulus \u2265 3.0 cm\/m2<\/sup>, aortic root \u2265 3.5 cm\/m2<\/sup>, mitral valve area \u2265 4.75 cm2<\/sup>\/m2<\/sup>, ratio of long axis of the left ventricle to the heart \u22650.8, and left ventricular cross-sectional area \u2265 2.0 cm2<\/sup>. The most common interventions which preserve biventricular anatomy include balloon aortic valvuloplasty (BAV) and surgical aortic valvotomy (SAV). The goal of either intervention is to reduce the aortic valve gradient and prevent aortic regurgitation.
\r\n\r\nBAV is performed in the cardiac catheterization lab. The aortic valve can be approached via the femoral, umbilical, or carotid arteries. It is recommended to use a balloon with a balloon to aortic valve annulus ratio of 0.8 to 1.0 to avoid over-dilation, which can result in significant aortic insufficiency (AI). A unicuspid aortic valve morphology is not always amenable to BAV due to increased risk of AI. After BAV, an immediate reduction in the peak pressure gradient across the valve is typically seen. The degree of immediate post-valvuloplasty insufficiency is predictive of late onset AI and suggests the likelihood for re-intervention.
\r\n\r\nSAV is performed in the operating room with cardiopulmonary bypass, cardioplegia, and hypothermic myocardial protection. Early surgical techniques for SAV were associated with roughly 50% mortality. However, advancements in surgical technique have improved mortality to a 100% 10-year survival. If not amenable to SAV, a valve replacement with a prosthetic or allograft valve may be performed. Alternatively, the Ross procedure may be performed in which the patient\u2019s pulmonary valve replaces the aortic valve. Prerequisites to the Ross procedure include a normal right ventricular outflow tract and pulmonary valve. The disadvantage of the the Ross procedure is the risk of future aortic and pulmonary valve disease.
\r\n\r\nEarly studies demonstrated equivocal outcomes in terms of survival and the need for re-intervention when comparing SAV and BAV. Advancements in surgical technique have demonstrated improved outcomes after SAV in more recent studies. In a study by Siddiqui et al, freedom from re-intervention at five years was 65% after SAV compared to 27% after BAV. Similar results were demonstrated in a meta-analysis by Hill et al in which BAV resulted in reduced gradient reduction, increased AI post-procedure, and greater need for subsequent intervention compared to SAV. Additionally, there was no difference in long-term survival and freedom from aortic valve replacement between the two groups, thus answer A is incorrect. The study also demonstrated a greater rate of additional intervention in the BAV group.
\r\n\r\nA study by Hermann et al demonstrated that SAV resulted in greater gradient reduction, reduced long-term AI, and a lower re-intervention rate at 10 years compared to BAV. However, SAV has been associated with higher morbidity and longer hospital stay compared to BAV. Studies have demonstrated no difference in mortality between the two groups. As a result, in this question the correct answer is C because there is less long-term aortic insufficiency in the SAV group. There is no difference in survival or rate of valve replacement between the two groups. Patients undergoing SAV require a longer hospital stay.
\r\n\r\nReferences:
\r\n\r\nSpaeth JP and Loepke AW. Anesthesia for Left-sided Obstructive lesions. In: Andropoulos, D, Stayer S, Mossad EB, Miller-Hance WC. Anesthesia for Congenital Heart Disease<\/em>. Third Edition. Hoboken, New Jersey: John Wiley & Sons, Inc. 2015, 497-515.
\r\n\r\nSingh, G. Congenital Aortic Valve Stenosis. Children (Basel)<\/em>. 2019; 6(5): 69. doi: 10.3390\/children6050069
\r\n\r\nHerrmann JH, Clark AJ, Colgate C, et al. Surgical valvuloplasty versus balloon dilation for congenital aortic stenosis in pediatric patients. World J Pediatr Congenit Heart Surg<\/em>. 2020; 11(4): 444-451. doi:10.1177\/2150135120918774.
\r\n\r\nMcCrindle B, Blackson EH, Williams WG, et al. Are outcomes of surgical versus transcatheter balloon valvotomy equivalent in neonatal critical aortic stenosis? Circulation<\/em>. 2001; 104: I152-158.
\r\n\r\nSiddiqui J, Brizard CP, Galati JC, et al. Surgical valvotomy and repair for neonatal and infant congenital aortic stenosis achieves better results than interventional catheterization. J Am Coll Cardiol<\/em>. 2013; 62(22): 2134-2140. doi:10.1016\/j.jacc.2013.07.052.
\r\n\r\nHill G, Ginde S, Rios R, Frommelt PC, Hill KD. Surgical valvotomy versus balloon valvuloplasty for congenital aortic valve stenosis: A systematic review and meta-analysis. J Am Heart Assoc<\/em>. 2016; 5(8): e003931. doi: 10.1161\/JAHA.116.003931.
\r\n\r\nBrown J, Rodefeld MD, Ruzmetov M, Eltayeb O, Yurdakok, Turrentine MW. Surgical valvuloplasty versus balloon aortic dilation for congenital aortic stenosis: Are evidence-based outcomes relevant? Ann Thorac Surg<\/em>. 2012; 94(1): 146-153. doi:10.1016\/j.athoracsur.2012.02.054. \r\n\r\n”,”redirect_url”:””}}}
- « Previous Page
- 1
- …
- 24
- 25
- 26
- 27
- 28
- …
- 32
- Next Page »