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

{“questions”:{“ntcoq”:{“id”:”ntcoq”,”mediaType”:”image”,”answerType”:”text”,”imageCredit”:””,”image”:””,”imageId”:””,”video”:””,”imagePlaceholder”:””,”imagePlaceholderId”:””,”title”:”Authors: Gibbs Yim, MD AND Nicholas Houska, DO – University of Colorado, Children\u2019s Hospital Colorado \r\n\r\nA 5-year-old boy presents with recurrent respiratory infections, chronic cough, and dysphagia. Computed tomography of the lungs confirms a right aortic arch with an aberrant left subclavian artery, consistent with a vascular ring. Which of the following vascular anomalies is MOST likely associated with this lesion? \r\n\r\n\r\n”,”desc”:”EXPLANATION \r\nKommerell\u2019s diverticulum is an aneurysmal dilation at the base of the left subclavian artery (LSA). It is most commonly associated with a right aortic arch and aberrant LSA but may also occur in a double aortic arch. Embryologically, the diverticulum is formed from the distal left fourth aortic arch. The tissue of the diverticulum is abnormally friable. A histopathologic study of resected diverticular tissue demonstrated cystic medial necrosis in more than half of the cases (Luciano et al.).\r\n\r\nA right aortic arch with aberrant LSA and left ligamentum arteriosum creates a vascular ring in which the trachea and esophagus are encircled by the pulmonary trunk and aorta anteriorly, the aortic arch to the right, an aberrant (retroesophageal) LSA posteriorly, and ligamentum arteriosum to the left. Right arch with aberrant LSA can present with symptoms of tracheoesophageal compression. When compared with a double aortic arch, a vascular ring due to a right arch with aberrant LSA generally presents later in childhood with less severe symptoms. In comparison with other right arch variants, it is less commonly associated with other congenital cardiac anomalies. If repair of the vascular ring is performed by simple ligation of the ligamentum without resection of the diverticulum, respiratory or esophageal symptoms may recur, then requiring additional surgical intervention. Additionally, the diverticulum is at risk for aneurysmal enlargement, rupture, and dissection. Therefore, primary resection of the Kommerell’s diverticulum is often recommended at the time of vascular ring repair. More conservative approaches include observation of the diverticulum, vessel plication, or vessel ligation. \r\n\r\nRepair of the vascular ring in a patient with a right aortic arch and aberrant LSA consists of ligation of the ligamentum arteriosum, resection of the Kommerell’s diverticulum, and reimplantation of the LSA onto the left common carotid artery. During diverticulum resection and LSA reimplantation, a portion of the descending aorta and the left common carotid artery may be clamped temporarily, which can impair perfusion to the abdominal organs and cerebral circulation, respectively. Intraoperative monitoring may include invasive or non-invasive blood pressure measurements of the right upper extremity, bilateral cerebral near-infrared spectroscopy, and either pulse oximetry or noninvasive blood pressure measurement of the lower extremities. Postoperative chylothorax is a known complication of vascular ring repair. \r\n\r\nThe correct answer is B. A right aortic arch with aberrant LSA is commonly associated with Kommerell\u2019s diverticulum. While interruption and coarctation of the aorta can be present in patients with a right aortic arch, they are much less common in the absence of a diagnosis of heterotaxy.\r\n\r\n\r\n \r\nREFERENCES \r\nLuciano D, Mitchell J, Fraisse A, Lepidi H, Kreitmann B, Ovaert C. Kommerell diverticulum should be removed in children with vascular ring and aberrant left subclavian artery. Ann Thorac Surg<\/em>. 2015;100(6):2293-2297.\r\n\r\nWorhunsky DJ, Levy BE, Stephens EH, Backer CL. Vascular rings. Semin Pediatr Surg<\/em>. 2021c;30(6):151128. doi: 10.1016\/j.sempedsurg.2021.151128. Epub 2021 Oct 23. PMID: 34930596.\r\n”,”hint”:””,”answers”:{“u95qt”:{“id”:”u95qt”,”image”:””,”imageId”:””,”title”:”A. Coarctation of the aorta”},”78esu”:{“id”:”78esu”,”image”:””,”imageId”:””,”title”:”B. Kommerell\u2019s Diverticulum”,”isCorrect”:”1″},”2hg8h”:{“id”:”2hg8h”,”image”:””,”imageId”:””,”title”:”C. Interrupted aortic arch”}}}}}

{“questions”:{“wy4e3”:{“id”:”wy4e3″,”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, MBBS, FAAP, FASA Children\u2019s Memorial Hermann Hospital, University of Texas Health Science Center, Houston, TX \r\n\r\nA 14-year-old patient with a history of long QT syndrome, not currently under treatment with medication or device therapy, is undergoing an appendectomy. During anesthesia emergence, sinus tachycardia at 150 bpm with non-sustained runs of Torsades de pointes are observed. Which of the following pharmacologic treatments for the arrhythmia has the HIGHEST risk of causing hemodynamic instability?”,”desc”:”EXPLANATION \r\nCongenital long QT syndrome (LQTS) is characterized by QT_{c<\/sub> prolongation on the electrocardiogram (ECG) and is associated with increased risk of life-threatening cardiac arrhythmias. LQTS results from heterogeneous genetic abnormalities of potassium or sodium ion channels involved in ventricular repolarization. It is the most common inherited arrhythmia syndrome, occurring in 1 out of every 2,500 individuals. It is associated with syncope, polymorphic ventricular tachycardia (Torsades des pointes) and sudden cardiac arrest. The rate of cardiac events is directly proportional to the degree of QTc<\/sub> prolongation. \r\n\r\nThe genetic mutations associated with LQTS are categorized into three subtypes, accounting for 95% of LQTS, and include LQT1, LQT2, and LQT3. LQT1 and LQT2 relate to mutations affecting potassium channels whereas in LQT3, mutations affect sodium channels. Patients with LQT1 are most triggered by sudden increases in sympathetic tone, such as stress or exercise. This is particularly notable with swimming, which has been associated with drowning in seemingly healthy young individuals. Patients with LQT2 are more prone to emotional stress, such as being frightened or startled. Patients with LQT3 are more likely to have events at rest. \r\n\r\nNonselective beta-blockers are first-line therapy, which can significantly decrease symptomatology, especially in those with LQT1 genotype. Cardiac sympathetic denervation can reportedly reduce the frequency of cardiac arrhythmia and is considered for patients who are intolerant of beta blockers or are poor candidates for cardiac implanted electronic devices.\r\n\r\nPerioperative considerations for patients with LQTS include continuing beta blockers, reducing sympathetic stimulation, avoiding QTc<\/sub> prolonging drugs, and ensuring normal electrolytes, especially potassium, calcium, and magnesium. Although many perioperative anesthetic drugs can prolong the QTc<\/sub>, they can be used without untoward effects. The recommendation is to minimize the simultaneous occurrence of arrhythmogenic triggers, such as avoiding the administration of QTc<\/sub> prolonging drugs during periods of catecholamine surges, for example administering ondansetron during anesthesia emergence. For treatment of sinus tachycardia, esmolol is a good choice for rapid rate control. Further, should Torsades des pointes (TdP) occur, magnesium sulfate is the treatment of choice. Lidocaine, a sodium channel blocker, is also safe to use for ventricular arrhythmias associated with LQTS because it does not prolong the QTc<\/sub> interval. Antiarrhythmic class III agents, such as amiodarone and sotalol, should be avoided because they prolong the action potential duration and refractoriness, which may exacerbate this arrhythmia.\r\n\r\nThe correct answer is C. Amiodarone can worsen the TdP, thus it should be avoided. This patient is having sinus tachycardia with non-sustained runs of TdP, therefore esmolol can be used for rate control of the sinus tachycardia, while lidocaine can be used to treat the non-sustained runs of TdP. Ultimately, magnesium is the treatment of choice for TdP. Cardioversion should be used in the setting of hemodynamically unstable arrhythmias.\r\n\r\n \r\nREFERENCES \r\n\r\nKuntz MT, Eagle SS, Dalal A, Samouil MM, Staudt GE, Londergan BP. What an anesthesiologist should know about pediatric arrhythmias. Paediatr Anaesth<\/em>. 2024;34(12):1187-1199. doi:10.1111\/pan.14980\r\n\r\nShah MJ, Silka MJ, Silva JNA,et al. 2021 PACES Expert Consensus Statement on the Indications and Management of Cardiovascular Implantable Electronic Devices in Pediatric Patients. Heart Rhythm<\/em>. 2021;18(11):1888-1924. doi:10.1016\/j.hrthm.2021.07.038\r\n\r\nValdes SO, Kim JJ, Miller-Hance W. Arrhythmias: Diagnosis and Management. In: Andropoulos DB, Mossad EM, Gottlieb EA, ed. Anesthesia for Congenital Heart Disease<\/em>. 4th ed. Hoboken, New Jersey: Wiley-Blackwell; 2023: 674-709\r\n\r\n”,”hint”:””,”answers”:{“l7tcu”:{“id”:”l7tcu”,”image”:””,”imageId”:””,”title”:”A. Esmolol”},”xy3od”:{“id”:”xy3od”,”image”:””,”imageId”:””,”title”:”B. Lidocaine”},”v0j2h”:{“id”:”v0j2h”,”image”:””,”imageId”:””,”title”:”C. Amiodarone”,”isCorrect”:”1″}}}}}}

{“questions”:{“obqkv”:{“id”:”obqkv”,”mediaType”:”image”,”answerType”:”text”,”imageCredit”:””,”image”:””,”imageId”:””,”video”:””,”imagePlaceholder”:””,”imagePlaceholderId”:””,”title”:”Author: Nicholas Houska, DO – University of Colorado – Children\u2019s Hospital Colorado \r\n\r\nA 1-year-old girl with a history of congenital mydriasis, patent ductus arteriosus ligation, and Ladd procedure presents for magnetic resonance imaging of the heart and brain. Genetic testing demonstrates a mutation of the ACTA2 <\/em>gene p.R179H consistent with Multisystem Smooth Muscle Dysfunction Syndrome. Which of the following complications is this patient at HIGHEST risk for while under general anesthesia?\r\n”,”desc”:”EXPLANATION \r\nSmooth muscle is located throughout the body and has numerous physiologic functions. Contraction depends on the interaction of myosin thick filaments and actin thin filaments, which are encoded on the ACTA2<\/em> gene on chromosome 10. Mutations in ACTA2 <\/em> have been associated with various smooth muscle disease phenotypes, with a specific de novo mutation of arginine residue 179 (R179) resulting in Multi System Smooth Muscle Dysfunction Syndrome (MSMDS). This disease was first described in 2010, and it is rare with less than 100 known cases worldwide. However, an increasing incidence can be attributed to improved recognition of the clinical manifestations and enhanced genetic testing. \r\n\r\n\r\nThe clinical manifestations of MSMDS are heterogeneous, but include congenital mydriasis, presence of a patent ductus arteriosus (PDA), pulmonary arterial hypertension, vascular aneurysms, Moyamoya-type cerebrovascular disease, internal carotid artery ectasia, intestinal\r\nhypoperistalsis and malrotation, cholelithiasis, prune belly syndrome, and hypotonic bladder. Signs and symptoms typically manifest at birth or in early childhood. The diagnosis is based on clinical suspicion, often triggered by conspicuously dilated pupils or other clinical characteristics and is confirmed by genetic testing. Current treatment is based on clinical manifestations, and requires a multi-disciplinary approach usually involving neurology, cardiology, ophthalmology, and urology. Research is currently being conducted into gene therapy as a curative measure. \r\n\r\n\r\nThese patients often require frequent hospitalization, procedures, and surveillance imaging including echocardiography and magnetic resonance imaging (MRI). Common procedures in these patients include PDA ligation, gastrointestinal and urological surgery, and bronchoscopy. This makes it pertinent for pediatric anesthesiologists to be aware of the anesthetic implications of this disease to mitigate periprocedural risk. Patients with MSMDS have dysfunctional autoregulation in blood pressure and are prone to hypotension, which can be profound when exposed to anesthetic agents with negative effects on systemic vascular resistance. Baseline diastolic hypotension is common and non-invasive blood pressure measurements are often inaccurate. A recent case series by Houska et al. showed that 40% of anesthetics in children with MSMDS required vasopressor administration to maintain a safe blood pressure. Given that these patients also have cerebrovascular disease that is like Moyamoya and carotid artery ectasia, the most serious complication of MSMDS is stroke. Most of these patients demonstrate white matter and chronic ischemic changes on MRI of the brain at an early age. The combination of a cerebrovascular disease and the inability to autoregulate blood pressure makes these children at high risk for anesthetic complications with large changes in blood pressure. Maintenance of blood pressure and cerebral perfusion should be the primary goal for the provider caring for these children. \r\n\r\n\r\nThe correct answer is A. Patients with MSMDS are at elevated risk for cerebrovascular accidents, particularly when exposed to drugs that reduce systemic vascular resistance. There has been no published literature suggesting an increased incidence of malignant hyperthermia or difficult intubation in patients MSMDS. \r\n\r\n\r\n \r\nREFERENCES \r\n\r\nHouska N, Schafer M, Chatfield KC, Bernard TJ, Ing RJ. Anesthetic considerations for children with multisystem smooth muscle dysfunction syndrome and review of the literature. J Cardiothorac Vasc Anesth<\/em>. 2022;36(8 Pt B):3205-3211.\r\n\r\n\r\nMilewicz DM, \u00d8stergaard JR, Ala-Kokko LM, et al. De novo ACTA2 mutation causes a novel syndrome of multisystemic smooth muscle dysfunction. Am J Med Genet A<\/em>. 2010;152A(10): 2437-2443.\r\n\r\n\r\nRegalado ES, Mellor-Crummey L, De Backer J, et al. Clinical history and management recommendations of the smooth muscle dysfunction syndrome due to ACTA2 arginine 179 alterations. Genet Med<\/em>. 2018;20(10):1206-1215.\r\n”,”hint”:””,”answers”:{“tigwl”:{“id”:”tigwl”,”image”:””,”imageId”:””,”title”:”A. Cerebrovascular accident”,”isCorrect”:”1″},”ful13″:{“id”:”ful13″,”image”:””,”imageId”:””,”title”:”B. Difficult intubation”},”p4g5v”:{“id”:”p4g5v”,”image”:””,”imageId”:””,”title”:”C. Malignant hyperthermia”}}}}}

{“questions”:{“xgzg9”:{“id”:”xgzg9″,”mediaType”:”image”,”answerType”:”text”,”imageCredit”:””,”image”:””,”imageId”:””,”video”:””,”imagePlaceholder”:””,”imagePlaceholderId”:””,”title”:”Author: Nicholas Houska, DO – University of Colorado, Children\u2019s Hospital Colorado \r\nA previously healthy five-month-old boy presents with a six-day history of fever, malaise, conjunctival redness, rash, and erythema of the tongue and oral mucosa. A diagnosis of Kawasaki disease is made based on clinical criteria. Echocardiography reveals a dilated left anterior descending artery with a z-score of 2.0. Which of the following factors places this patient at the HIGHEST risk of developing coronary artery aneurysms?\r\n\r\n”,”desc”:”EXPLANATION \r\nKawasaki Disease (KD) is a febrile illness of unknown etiology, with associated vasculitis that primarily affects young children. First described in Japan in 1967, it is now known for its potential for coronary artery (CA) complications and is the most common cause of acquired heart disease in developed countries. It has an incidence in North America of approximately 25 cases per 100,000 children aged less than 5 years per year. The incidence is higher in East Asian countries, with children of this ancestry at higher risk for development of KD. \r\n\r\n\r\nKD typically presents with high fever for longer than five days in duration, erythema and swelling of the palms and soles followed by desquamation, diffuse maculopapular rash, cervical lymphadenopathy, nonexudative conjunctivitis, and oral cavity erythema (strawberry tongue). The diagnosis is made by clinical criteria. Patients who do not meet full criteria but have a high index of suspicion and symptoms consistent with KD are often diagnosed with incomplete KD and may also warrant therapy.\r\n\r\n\r\nKD constitutes an immune response of unknown cause characterized by systemic inflammation of medium-sized muscular arteries, the most serious of which are coronary arteries. Coronary dilation may be acute, subacute, or chronic, and dilation may lead to aneurysm, thrombosis, or rupture. Myocardial infarction (MI) can occur from thrombosis or chronic stenosis. For patients with minimal coronary artery dilation and early treatment with a good response to intravenous immunoglobulin (IVIG), coronary artery changes are typically transient with 98.6% having normal echocardiograms one to two weeks after discharge. Left anterior descending or right coronary artery z-score is the strongest predictor of outcomes. Risk factors for the development of coronary artery aneurysm (CAA) include a z-score greater than 2.5 at diagnosis and an age less than six months (Jone et al.). Recent guidelines recommend intensification of therapy for high-risk patients. \r\n\r\n\r\nThe standard treatment for KD is aspirin and IVIG. Fever and symptom improvement are expected shortly after initiation of therapy. Additional anti-inflammatory agents are recommended for patients with IVIG resistance, which is defined as fever persistence for greater than 36 hours after initial completion of IVIG, and patients at high-risk for CAA development. These include corticosteroids, tumor necrosis factor \u03b1 inhibitors (infliximab and etanercept), an interleukin-1 inhibitor (anakinra), and cyclosporine. Patients may also warrant thrombosis prophylaxis with anti-platelet agents and other anti-coagulants. The risk of MI is highest in the first two to three months after KD onset but may persist in adults with CAA. Acute coronary syndrome (ACS) may present with atypical symptoms in children. ACS in pediatric patients is divided into ST-segment elevation MI and non-ST segment elevation MI. Treatment recommendations are based on adult management, with an emphasis on rapid revascularization. \r\n\r\n\r\nThe correct answer is B. The patient in the question stem is less than six months of age and is at high risk for developing CAA. A fever greater than five days in duration is typical with KD. Treatment within ten days of fever onset is associated with a reduced risk or CA dilation or aneurysm . Left anterior descending artery z-score of 2.5 is associated with increased risk of CAA. \r\n\r\n\r\n\r\n\r\n\r\n \r\nREFERENCES \r\n\r\nJone PN, Tremoulet A, Choueiter N, et al. Update on diagnosis and management of Kawasaki disease: a scientific statement from the American Heart Association. Circulation<\/em>. 2024;150(23):e481-e500.\r\n\r\n\r\nMcCrindle BW, Rowley AH, Newburger JW, et al. Diagnosis, treatment, and long-term management of Kawasaki disease: a scientific statement for health professionals from the American Heart Association. Circulation<\/em>. 2017;135(17):e927-e999.\r\n\r\n\r\nTo L, Krazit ST, Kaye AD. Perioperative considerations of Kawasaki disease. Ochsner J<\/em>. 2013;13(2):208-213.\r\n\r\n”,”hint”:””,”answers”:{“cqod3”:{“id”:”cqod3″,”image”:””,”imageId”:””,”title”:”A. Left anterior descending artery z-score of 2.0″},”0knmp”:{“id”:”0knmp”,”image”:””,”imageId”:””,”title”:”B. Age less than six months”,”isCorrect”:”1″},”f4jhm”:{“id”:”f4jhm”,”image”:””,”imageId”:””,”title”:”C. Fever greater than five days duration”}}}}}

{“questions”:{“r5ea7”:{“id”:”r5ea7″,”mediaType”:”image”,”answerType”:”text”,”imageCredit”:””,”image”:””,”imageId”:””,”video”:””,”imagePlaceholder”:””,”imagePlaceholderId”:””,”title”:”Authors: Mackenzie Schumer, CAA AND Nicholas Houska, DO – University of Colorado, Children\u2019s Hospital Colorado\r\n\r\n\r\nA 15-year-old, 52 kg boy with Marfan\u2019s syndrome, aortic root dilation, and severe aortic regurgitation undergoes the Bentall procedure with a mechanical aortic valve replacement. The postoperative course is complicated by severe left ventricular dysfunction. Which of the following patient attributes is a contraindication for placement of an Impella\u00a9 5.5 left ventricular assist device?”,”desc”:”EXPLANATION \r\nThe Impella\u00ae is a short-term ventricular assist device (VAD) used to provide ventricular support in the setting of cardiogenic shock following acute myocardial infarction, acute transplant rejection, cardiac surgery, high-risk percutaneous coronary interventions or for the management of cardiomyopathy. The Impella\u00ae can be used in patients on extracorporeal membrane oxygenation (ECMO) for left ventricular unloading. The Impella 5.5\u00ae is also used as a bridge to heart transplantation. The Impella 5.5\u00ae is placed surgically via a direct transaortic approach or through right or left axillary artery cutdown and graft. It is placed within the left ventricle (LV), across the aortic valve, and utilizes a catheter-based microaxial pump to displace blood from the LV into the ascending aorta, providing up to 6 L\/ min of flow. Other iterations of the Impella\u00ae include the Impella CP\u00ae, which is placed percutaneously through the femoral artery and allows flows up to 4.3 L\/min, and the Impella RP\u00ae, which is used for right ventricular support and provides a flow rate of up to 4 L\/min. \r\n\r\nPlacement of an Impella 5.5\u00ae is contraindicated in patients with severe aortic stenosis or calcification with a valve area less than 0.6 cm^{2<\/sup>, LV thrombus, moderate or severe aortic insufficiency, presence of an atrial or ventricular septal defect, and presence of a mechanical aortic valve. Complications of the Impella\u00ae include damage to the aortic valve, ascending aorta, aortic root, and coronary sinuses, stroke, hemolysis, acute renal failure, and thrombocytopenia.\r\n\r\nThe Impella 5.5\u00ae can be used in the pediatric population if the patient can accommodate the 21 French (Fr) cannula that crosses the aortic valve. The device is 114 mm in length and is mounted on a 9 Fr catheter for implantation. While large studies do not exist in pediatric patients, there are published case reports of Impella\u00ae implantation in pediatric patients with most utilizing computed tomography or fluoroscopy for measurement and modeling of the aortic annulus, ascending aorta, aortic arch vessels, and LV cavity in conjunction with guided navigation for implantation. The Impella 5.5\u00ae and CP\u00ae have recently been approved by the U.S. Food and Drug Administration for use in pediatric patients weighing greater than or equal to 30 kg and greater than or equal to 52 kg respectively. However, the Impella\u00ae continues to be used off-label in smaller patients using vessel and LV size for guidance.\r\n \r\nThe patient described in this case underwent a Bentall procedure. In this case, he received a mechanical aortic valve which excludes him from Impella 5.5\u00ae implantation, making C. the correct answer. As discussed above, this patient\u2019s age and weight do not exclude Impella 5.5\u00ae use. However, measurements of the aortic valve annulus and aortic arch vessels, along with a three-dimensional rendering of LV size can help to determine if an Impella 5.5\u00ae catheter can be positioned appropriately in pediatric patients regardless of age or weight.\r\n\r\n\r\n \r\nREFERENCES \r\nAbiomed. Impella\u00ae 5.5 with SmartAssist\u00a9 instructions for use. https:\/\/d1edr79mp9g5zc.cloudfront.net\/5eb0affe-1991-449b-bfc0-a5a0516548bf\/cb8ef4bf-4fb9-46ed-91d7-6117f06bb18e\/cb8ef4bf-4fb9-46ed-91d7-6117f06bb18e_source__v.pdf . Accessed February 6, 2025. \r\n\r\nGlazier JJ, Kaki A. The Impella Device: Historical Background, Clinical Applications and Future Directions. Int J Angiol<\/em>. 2019;28(2):118-123. doi:10.1055\/s-0038-1676369\r\n\r\nOelkers B, Schumer E, Lambert AN, Alsoufi B, Kozik D, Wilkens SJ. The Use of Impella 5.5 Reduces Pulmonary Vascular Resistance as Bridge to Heart Transplant in a Pediatric Patient. ASAIO J<\/em>. 2025;71(3): e46-e47. doi:10.1097\/MAT.0000000000002256\r\n\r\nPediatric Cardiology. FDA Expands Indication for Impella Heart Pumps for Pediatric Patients. December 18, 2024. Accessed February 6, 2025.\r\nhttps:\/\/www.dicardiology.com\/content\/fda-expands-indication-impella-heart-pumps-pediatric-patients\r\n”,”hint”:””,”answers”:{“uccin”:{“id”:”uccin”,”image”:””,”imageId”:””,”title”:”A. Age”},”n3lsi”:{“id”:”n3lsi”,”image”:””,”imageId”:””,”title”:”B. Weight”},”hiqvf”:{“id”:”hiqvf”,”image”:””,”imageId”:””,”title”:”C. Mechanical aortic valve”,”isCorrect”:”1″}}}}}}