CCCardiol CroatCardiologia CroaticaCardiol. Croat.1848-543X1848-5448Croatian Cardiac SocietyCC 2020 15_11-12_296-30510.15836/ccar2020.296Review ArticleReport on the Adult Congenital Heart Disease Multidisciplinary Team Meeting Held During the COVID-19 PandemicIzvještaj sa sastanka multidisciplinarnog tima za prirođene srčane bolesti odraslih održanog u vrijeme pandemije COVID-a 19https://orcid.org/0000-0003-4596-8261StrozziMaja*https://orcid.org/0000-0001-8754-8156BridaMargaritahttps://orcid.org/0000-0003-3490-5505DošenDenishttps://orcid.org/0000-0002-5052-6559LovrićDanielhttps://orcid.org/0000-0002-7378-944XAnićDarkohttps://orcid.org/0000-0002-6910-9720Ivanac VranešićIrenahttps://orcid.org/0000-0002-4004-7271Marić BešićKristinahttps://orcid.org/0000-0002-9833-832XPlanincMislavhttps://orcid.org/0000-0002-9602-7114MeđimurecGoranhttps://orcid.org/0000-0002-0390-8466Hrabak PaarMajaMedicinski fakultet Sveučilišta u Zagrebu, Klinički bolnički centar Zagreb, Zagreb, HrvatskaUniversity of Zagreb School of Medicine, University Hospital Centre Zagreb, Zagreb, CroatiaADDRESS FOR CORRESPONDENCE: Maja Strozzi, Klinički bolnički centar Zagreb, Kišpatićeva 12, HR-10000 Zagreb, Croatia. / Phone: +385-1-2367-508 / E-mail: maja.strozzi@gmail.com1120201511-122963051708202017102020281020202020Croatian Cardiac SocietySAŽETAK
U svrhu obilježavanja pete godišnjice sustavne brige za odrasle bolesnike s prirođenom srčanom bolesti organizirali smo u Nacionalnom centru u Kliničkom bolničkom centru Zagreb sastanak uz prikaz kompleksnih kliničkih slučajeva iz tog područja. Zbog pandemije COVID-a 19 sastanak je otkazan, ali je umjesto toga održan multidisciplinarni konzilij uz sudjelovanje vrhunskoga međunarodnog stručnjaka. Prikazano je više bolesnika i doneseni zaključci o njihovu daljnjem liječenju. Ovdje iznosimo podatke o četirima bolesnicima: o dva bolesnika sa slučajno otkrivenom kasnom dijagnozom prirođene srčane bolesti (o jednom s atrijskim septalnim defektom i drugom s Fallotovom tetralogijom), o bolesnici sa slomom Fontanove cirkulacije, liječenom transplantacijom srca te o bolesnici s transpozicijom velikih krvnih žila i problemima nastalima nakon operacije. Uz prikaze bolesnika, u raspravama su iznesene dvojbe u vezi s liječenjem te najvažniji zaključci vezani uz svaki pojedini slučaj.
SUMMARY
To mark the fifth anniversary of systematic care for adult patients with congenital heart disease, we organized a meeting at the National Center at the University Hospital Centre Zagreb with the intention of presenting complex clinical cases from the field. The meeting was canceled due to the COVID-19 pandemic, but a multidisciplinary council was held with the participation of an international top expert. Several patients were presented and conclusions were made about their further treatment. Herein we present four interesting cases: two patients with an accidental late diagnosis, one with atrial septal defect and a second with tetralogy of Fallot, a patient with failing Fontan circulation treated by heart transplantation, and a patient with surgically corrected transposition of great arteries with postoperative problems. In addition to patient reports, the discussions sections present dilemmas about treatment, available literature, and conclusions related to each case.
KLJUČNE RIJEČI: prirođena bolest srca odraslihatrijski septalni defekttetralogija FallotFontanova cirkulacijatranspozicija velikih krvnih žilatransplantacija u kongenitalnoj bolestiperkutana aortalna valvula u kongenitalnoj bolestiKEYWORDS: atrial septal defecttetralogy of FallotFontan circulationtransposition of great arteriesheart transplant in congenital heart diseasepercutaneous aortic valve in congenital heart diseaseIntroduction
It is well known that the number of adult patients with congenital heart disease (ACHD) is rapidly growing (1). Specialized care for these patients is crucial, and there are now well established ACHD centers in many countries (2). Croatia has a relatively young National ACHD Tertiary Centre at the University Hospital Centre Zagreb, established approximately 5 years ago. During this time period, good results were achieved regarding the organization of care, patient treatment, establishment of a registry, education, and publishing. Particular attention has been given to increasing knowledge and raising awareness regarding ACHD of colleagues in the local communities and involving them in the treatment of these complex cases (3).
For these reasons, we scheduled a meeting on the topic of challenging ACHD cases in Zagreb, March 13, 2020. The goal was to present complex clinical cases and reach conclusions regarding the best treatment according to current guidelines and expert opinion (4). Unfortunately, the official meeting was cancelled a day earlier due to the CORONA-19 pandemic. Nevertheless, a part of the participants gathered, including our special guest from the London Royal Brompton Hospital, professor Michael Gatzoulis, and we held a small meeting of experts respecting all the prescribed epidemiological measures.
In this paper we summarize the main points and conclusions from the meeting. We focused on four topics based on the presented cases, which we also believe are of interest to the wider audience of cardiologists.
Late diagnosis of atrial septal defect
Case report: A 53-year-old woman was admitted to our cardiology department with symptoms of unstable angina. Echocardiography showed a large secundum atrial septal defect (ASD) with predominantly left to right shunt (L-R), dilated right ventricle (RV), and reduced systolic left ventricular (LV) function. The size of the defect was 3.2 cm, and systolic pulmonary artery pressure was estimated at 80 mmHg, indicating severe pulmonary hypertension (PH). The pulmonary artery was dilated, and the defect was unsuitable for percutaneous closure on transesophageal echocardiography (TEE). Additionally, regional wall motion abnormalities of the LV were also detected. Consequently, coronary angiography with intravascular ultrasound (IVUS) was performed and severe stenosis of the left main coronary artery (LMCA) was found. Percutaneous coronary intervention (PCI) of the LMCA was performed, resulting in prompt recovery of the LV systolic function (Figure 1). Since right heart catheterization showed increased pulmonary pressure values (85/21/47mmHg) and high pulmonary vascular resistance (PVR 7.5 WU), bosentan therapy was initiated. There was no evidence of right to left shunt on heart catheter and magnetic resonance imaging and the L-R shunt was calculated as 2.1-2.5:1. There was no significant reduction in PVR values in further follow-up, so closure was not recommended.
Transthoracic echocardiography of a patient with atrial septal defect, showing interatrial communication (A) and the dilatated pulmonary artery (B), as well as coronary angiography of the left coronary artery before and after LMCA stenting (C, D).
Discussion: ASD with a L-R shunt is rarely connected with the rise in pulmonary vascular resistance. The majority of patients can undergo closure, either percutaneous or surgical. Perioperative mortality and morbidity are extremely low. Mid to longer term survival is excellent irrespective of age, gender and mode of closure, and similar to a matched general population (5). We have similar experience, i.e. benefit from repair in patients older than 50 years (6).
There were considerable challenges in this case. Until the development of coronary disease symptoms, the patient seemed to be oligosymptomatic. However, our findings demonstrated severe pulmonary hypertension and a mild reduction of systolic RV function. There was no evidence of other PH etiology. The main reason for continuation of conservative therapy was high PVR with no improvement on specific PH therapy. There was also a question of coronary LM stenosis as the etiology. The pulmonary trunk enlargement compressing the LM could be a possible reason, as described in the literature (7).
In patients with PH, the decision whether or not to close the defect can be challenging. Different clinical PAH scenarios can be encountered. At one end of the spectrum there are adults with only mild pulmonary vascular disease and a large shunt. At the other end of the spectrum are adults with severe, irreversible pulmonary vascular disease, shunt reversal and chronic cyanosis, i.e. Eisenmenger syndrome (8). Clinically, our patients corresponded more closely to the first group. There have been some case reports of shunt closure after targeted medical therapy in selected patients with ASD and significant PAH (9). Reduction of PH with bosentan therapy was not achieved in our patient. In case of doubt regarding closure, there is also an option of fenestrated surgical closure of the defect to decrease the degree of atrial mixing, but still allow atrial decompression if necessary (10).
Last but not least, when evaluating the option of shunt closure, it is important to consider the invasive hemodynamic data in the context of the clinical picture, the defect anatomy, and further non-invasive tests. There are many pitfalls in catheter laboratory calculation that can give an inappropriate number of PVR. It is of outmost importance that the right heart catheterization is performed by an expert interventional ACHD cardiologist, taking into account issues such as the maximal oxygen uptake per minute (VO2) calculation, selection of value/sample of mixed venous blood saturation (11), technical problems when measuring left atrial pressures, etc.
Conclusion:
Late diagnosis of ASD is not uncommon in everyday practice. It can be triggered by other problems, and in this case the patient presented with unstable angina. The coronary target lesion might have been connected with the primary disease and dilatation of the PA.
If there is no contraindication (primarily PH and severe left heart disease with high pressure) the defect should be closed regardless of age at presentation.
Right heart catheterization is a gold standard. Correct assessment of PVR is crucial. There are considerable pitfalls in catheter laboratory calculation of the right sided pressures that need to be taken into consideration. If the numbers are ambiguous and not in concordance with other data, the patient should be re-evaluated. This is the plan for our patient.
Tetralogy of Fallot indications for surgery in patients with late presentation
Case report: A male patient born in 1970 presented in the Centre for evaluation after accidental finding of heart murmur on routine preoperative examination (hernia). He was healthy until 2018 and was a soldier in a special unit during the war in Croatia back in the 1990s, working in mine fields for many years. He did not feel any reduction in his physical capacity but did feel experience some palpitations. On clinical examination, there was a loud systolic murmur over the pulmonary valve and the patient’s stress test was reduced, with only 7.5 MET and ST-segment depression of 2 mm on ECG, with both ventricular and supraventricular premature beats.
Coronary angiography was performed, and a left anterior descending artery LAD bridging without significant stenosis was found. 24-hour ECG monitoring did not reveal significant arrhythmia. Finally, echocardiography showed an overriding aorta and a large ventricular septal defect (VSD) with a bidirectional shunt, a hypertrophic and enlarged right ventricle with good systolic function, and near systemic pressures. A high-grade pulmonary valve stenosis, (PS gradient of 100 mmHg) was present, and good left ventricular function (EF 65%), enlarged aortic root, and a hypo-plastic pulmonary trunk were found. The anatomy was confirmed by a CT scan (Figure 2).
Echocardiography and CT scan of unoperated tetralogy of Fallot, showing a large ventricular septal defect with overriding aorta (A, C) and high gradient through stenotic pulmonary valve (B).
Discussion: A patient with unoperated tetralogy of Fallot (TOF) presented for the first time in adult age. Accidental finding of an unknown congenital heart disease during a routine medical health check-up is rare (1%), and in the majority of cases these are simple defects such as ASD or bicuspid aortic valve (12). TOF prognosis is poor, and less than 15% survive to an adult age (13). Some case reports or patient series in the literature reputed data on the results of late TOF surgical repair. Perioperative mortality is 5-8%, depending on patient characteristics. High PS gradient, high hematocrit, lower oxygen saturation, reduced RV function, and presence of comorbidities carries greater risk (14). Of our own 4 patients who underwent late TOF repair at a mean age of 36 years (29-53) at time of surgery, in the 11 years (4-21) of follow-up, one patient died after 4 years during heart transplantation, one needed pulmonary valve replacement after 20 years, and two patients are still in good clinical condition after 13 and 5 years. In this case of a late recognized TOF that was practically asymptomatic and with possible presence of arrhythmia, we discussed the positives and negatives of complete repair such as relatively low perioperative risk, future risk of RV failure, arrhythmia occurrence, paradoxical embolization without operation, etc. The patient, however, has not decided on surgery so far.
Several complications have been reported in the biggest case series of patients operated late for TOF repair in the literature, such as postoperative low cardiac output syndrome, with the most common being severe pulmonary insufficiency (15). That is the reason for implantation of a tissue valve being preferred instead of repair in adult patients. As for the long-term outcomes, 10-year survival in one study was 73%, which is low but better than would be expected for those with unrepaired TOF (16).
The main problems after late repair are similar to those in children: arrhythmia, PV stenosis and/or regurgitation, in this scenario caused by biological valve degeneration, possible (rare) reopening of VSD, reduction of ventricular function (right and left), etc.
Conclusion:
Late presentation of TOF is rare and usually associated with a well-balanced hemodynamic condition. Complete TOF correction in patients older than 30 years is possible and advisable with acceptable risk.
The surgical approach to pulmonary stenosis in late TOF repair is pulmonary valve replacement.
Problems expected after late repair are similar to those operated in early childhood, sometimes with need for additional procedures.
Fontan circulation and heart transplantation
Case report: 25-year-old female patient with Fontan circulation first time presented at the Centre for the first time, after having previously been periodically monitored abroad. Prior to referral, the patient had shown signs of failing Fontan circulation with protein-losing enteropathy (PLE) for several years; transplantation was suggested as the best treatment option and she was referred to our Centre. The initial evaluation found a single ventricle with preserved systolic and diastolic function, with both mitral and tricuspid valve having no signs of insufficiency (Figure 3). She had an extracardiac conduit with visible fenestration. Gastroenterology work-up showed a significant degree of hepatic congestion with development of hepatic fibrosis (Fibroscan measured stiffness of 15.1 kPa), splenomegaly, esophageal varices, and hypertensive gastropathy. However, laboratory findings of prothrombin time, alanine aminotransferase, aspartate aminotransferase, as well as gamma-glutamyltransferase were normal, which led our gastroenterology team to conclude that the synthetic liver function was preserved. Renal function was moderately decreased as well (creatinine clearance of 47 mL/min), which was attributed to a long-term high dose diuretic. No contraindication for heart transplantation was found and the patient was placed on the transplant recipient list where she spent the following two years without an offer. During that time, she was regularly clinically reviewed during hospital follow-up visits which showed ongoing hypoproteinemia, stable, non-progressive renal failure, and slight elevation of liver enzymes. She required on-going albumin administration.
Echocardiography of single ventricle anatomy (A) and flow through Fontan fenestration in 2D (B) and M Mode (C).
The patient underwent heart transplantation after two years, and the surgery itself was successful except for a prolonged hemostasis. However, a few hours after the surgery the patient shows signs of hypovolemic shock and surgical revision was immediately necessary due to intrathoracic bleeding, with subsequent placement of veno-arterial extracorporeal membrane oxygenation (ECMO) due to hemodynamic instability. The patient’s clinical course worsened, with severe renal failure demanding continuous veno-venous hemodialysis and subsequent development of paralytic ileus with worsening ascites. 18 days after transplantation, the patient started showing signs of abdominal compartment syndrome, leading to abdominal surgery. 2300 mL of bloody ascites was evacuated, and visual inspection of the liver showed clear signs of micronodular cirrhosis. The patient died the following day.
Discussion: In patients with Fontan circulation, ventricular failure (50%) and PLE (40%) are the top two most common reasons for transplant referral (17). Lymphatic failure in patients with Fontan circulation is exceptionally challenging from a management perspective not only because of the limited treatment options but also because many of these patients have seemingly normal hemodynamics (18), and presence of PLE is an independent risk factor for mortality (19).
Fontan-associated liver disease is a known entity secondary to chronic liver congestion in patients after Fontan completion. The degree of fibrotic change appears to only be associated with the length of time spent with Fontan circulation and not with hemodynamic or other systemic factors, suggesting that the disease directly results from the Fontan circulation (20). Monitoring the progression of liver disease can be very challenging, as even patients with advanced disease tend to be asymptomatic with near normal biochemical and functional hepatic tests (21).
Survival after transplantation in pediatric patients has significantly improved in recent times (22). However, adult patients with Fontan circulation still have significantly worse outcomes after transplantation in comparison with acquired heart disease and cardiomyopathies (23). These patients have a greater than threefold risk of death within one year compared with other groups. Furthermore, these patients may not meet urgent listing criteria and thus may have a longer wait list time. During transplantation, in addition to liver disease these patients often develop kidney failure, often have some degree of sensitization and relative immunosuppression, significant vasoplegia, and increased pulmonary vascular resistance, while surgical challenges include complex pulmonary artery reconstructions, long cardiac bypass times, and increased risk of hemorrhage (21). Our patient, unfortunately, faced most of these complications leading to a lethal outcome.
Conclusion:
Patients with failing Fontan circulation due to their specific issues, even if ventricular function is preserved, have worse heart transplantation survival rates compared with patients with impaired cardiac function.
There are still no clear guidelines when selecting patients with Fontan circulation for transplantation due to the paucity of available data.
Fontan-associated liver disease is an extracardiac complication that may lead to substantial comorbid disease and premature mortality. Heart transplantation is contraindicated if significant cirrhosis is present, which was been discovered late in our patient, but a combined heart-liver transplant can be considered.
Problems after arterial “switch” in patients with transposition of the great arteries
Case report: We treated a female patient born in 1987 with complex congenital heart defects, D-transposition of the great arteries (TGA), atrial and ventricular septal defect, patent ductus arteriosus, and aortic coarctation and duct closure. She underwent initial surgeries in 1988 – an arterial switch surgery with closure of the defects and a CoA surgery. Subsequently during childhood, she required two additional surgeries due to re-CoA and neo-aortic regurgitation, with implantation of a 25mm biological prosthesis in the aortic position. Her clinical course in adulthood was uneventful, and she successfully underwent pregnancy and delivery of a healthy baby boy in 2011. During her regular follow-up, it became clear that her biological valve prosthesis had degenerated, however, having a baby boy, the young mother was reluctant to undergo another open-heart surgery. After a long conversation with her, a decision was made to offer her a transcatheter valve, and in 2013 she underwent transapical minimally invasive “valve-in-valve” implantation with a 26 mm balloon-expandable transcatheter valve (Sapien XT, Edwards Lifesciences Inc., Irvine, CA). The echocardiographic postprocedural mean and maximum gradient were 14 and 23 mmHg, respectively, and she was in excellent clinical condition and could return to her child immediately. She was asymptomatic for more than 7 years. This year, in 2020, she started experiencing breathlessness on physical exertion and performed poorly on her exercise test, managing only 3 minutes due to dyspnea. Her max. VO2 was only 16 mL/kg/m2. She had no significant arrhythmias, but her blood tests revealed elevated NT-proBNP of 2011 ng/L. Her echocardiography showed severe stenosis of the previously implanted TAVI, and her CT scan showed a dilated ascending aorta (neo-aorta) of 47 mm and right pulmonary artery (RPA) stretch-stenosis of 5 mm. The findings of the aortic dilatation and RPA stenosis were known from her previous examinations and had not progressed during the 5-year time period (Figure 4). It was clear that she needed to be relieved of her valve stenosis, and the question was whether to undergo a large but hopefully defining surgical procedure addressing the valve, ascending aorta, and perhaps also stretched RPA stenosis, or low risk valve-in-valve transcatheter intervention. The decision was made and she underwent “TAVI-in-TAVI” with an excellent result once again, a max. PG of only 20 mmHg after the intervention. Three months later, her NT-proBNP levels were normal and she performed a maximal exercise test without any symptoms.
CT scan (A, B) and echocardiography of a patient with transposition of great arteries after a “switch” surgery, resulting in right pulmonary artery stenosis caused by aortic dilatation.
Discussion: Arterial switch operation in D-TGA, i.e. morphological repair, restores normal structure of the heart (24). However, these patients often experience complications later in life such as supravalvular pulmonary stenosis and branch PA stenosis, supravalvular aortic stenosis, neo-aortic root dilation, neo-aortic regurgitation, coronary artery stenosis, LV dilatation and dysfunction, pulmonary hypertension, etc. Some of these complications might be significant and require additional surgery or intervention during childhood or in adulthood (25). Our patient had an on-going issue with her neo-aortic valve that needed to be addressed. We unconventionally decided to take a non-established approach to accommodate the wishes of a young mother and engaged in a transcatheter valve-in-valve and TAVI-in-TAVI approach with excellent results. Her ascending aorta dilatation and stretch stenosis of the RPA as well as biological TAVI require regular follow-up.
Conclusion:
In contrast to atrial switch repair, arterial switch repair restores normal heart anatomy in patients with D-TGA.
However, long-term issues after repair are common. Complications need to be checked for both in childhood and adulthood. Supravalvular and branch pulmonary artery stenosis are the most common long-term complication due to the residual suture line and LeCompte maneuver; neo-aortic root dilatation is almost universal but may stabilize in adult life; aortic regurgitation requires meticulous follow-up; coronary artery problems are mainly seen in the pediatric cohort in the early postoperative period and in the early surgical era (<1990), but subtle regional wall motion abnormalities and/or progressive ventricular dilatation in adults should be investigated.
Decision-making is challenging and should include an multidisciplinary expert team taking into account this young population with their specific needs and issues.
Since we are unable to hold the planned national ACHD meeting due to the national lockdown during the COVID-19 pandemic, we would like to share the conclusions from our expert meeting on some treatment dilemmas in complex adult congenital heart disease cases. We hope that publishing this article in our national cardiology journal is the best way to inform potential meeting participants about these topics, but also inform other cardiologists who have an interest in congenital heart disease.
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