[Pulmonary hypertension in adults with congenital heart disease in light of the 2022-ESC-PAH guidelines - Part II: Supportive therapy, special situations (pregnancy, contraception, non-cardiac surgery), targeted pharmacotherapy, organ transplantation, special management (shunt lesions, left ventricular disorders, univentricular hearts), interventions, intensive care, follow-up, future perspectives]. / Pulmonale Hypertonie bei Erwachsenen mit angeborenen Herzfehlern im Lichte der 2022-ESC-PAH-Leitlinien.

The number of adults with congenital heart defects (CHD) is steadily rising and amounts to approximately 360,000 in Germany. CHD is often associated with pulmonary hypertension (PH), which may develop early in untreated CHD. Despite timely treatment of CHD, PH not infrequently persists or recurs in older age and is associated with significant morbidity and mortality.The revised European Society of Cardiology/European Respiratory Society 2022 guidelines for the diagnosis and treatment of PH represent a significant contribution to the optimized care of those affected. However, the topic of "adults with congenital heart disease" is addressed only relatively superficial in these guidelines. Therefore, in the present article, this topic is commented in detail from the perspective of congenital cardiology.

Real-time CMR guidance for intracardiac and great vessel pressure mapping in patients with congenital heart disease using an MR conditional guidewire-results of 25 patients.

BACKGROUND: The aim of this study was to test a CE-certified MR-conditional guidewire to facilitate blood pressure measurement in cardiovascular magnetic resonance (CMR) using fluid-filled catheters in patients with congenital heart disease (CHD). The main purpose was to determine procedural success in a post market clinical follow-up (PMCF) for routine procedure in a diagnostic and interventional workflow. Real-time CMR provides high quality imaging without the risk of exposing the patient to X-rays, especially for patients with irregular heart anatomy and patients who are susceptible to radiation and iodinated contrast media. To date, the assessment of blood pressure gradients is not a common feature of CMR, as these gradients cannot be accurately evaluated in routine CMR. METHODS: Twenty-five CHD patients who were planned for combined clinical CMR and diagnostic and/or interventional catheterization were enrolled in the trial. Prior to inclusion, a specific procedure for catheterization in CMR was defined, encompassing the assessment of pressure and pressure gradients in the heart and great vessels. RESULTS: By the use of an MR-conditional guidewire we successfully measured specific pressure and pressure gradients in up to 92% of cases with liquid-filled catheters which were guided exclusively under CMR guidance. There were no guidewire-related adverse events, and guidewire guidance and manipulation of catheters were successful. CONCLUSIONS: Using a MR-conditional guidewire assists in easily reaching targets in the heart and great vessels and makes the catheter itself visible, so that invasive blood pressure assessment by CMR guidance with liquid-filled catheters can be improved. KEYWORDS: Cardiovascular magnetic resonance (CMR); congenital heart disease (CHD); cardiac catheterization; magnetic resonance; pressure; guidewire.

Management of a doubly folded, partially inflated Melody valve after outer balloon rupture: a case report.

This is a report of a rare complication during implantation of a Melody valve in an adult patient in whom the valve failed to expand due to balloon rupture. An 18-year-old patient was admitted with an increased right ventricular pressure and severe pulmonary regurgitation for scheduled cardiac catheterization. Angiography revealed a proximal stenosis of the left pulmonary artery (LPA). First, a prestenting was performed. Three months later he came back for planned percutaneous pulmonary valve implantation (PPVI). Because of the proximity of the right coronary artery (RCA) to the right ventricular outflow tract (RVOT) and thus a relatively short landing zone, the Melody valve had been doubly folded. During the inflation of the outer balloon, it ruptured. At this point, the Melody valve was still fixed to the inner balloon. A second catheter was placed through the Melody valve and successful valve implantation was possible. This procedure was difficult because to push the catheter through the partly inflated Melody valve, the inner balloon had to be slowly and simultaneously deflated. The final angiograms and pressure measurements showed a good functional result and absent pulmonary regurgitation. Open heart surgery could be avoided after incomplete Melody valve dilatation using the contralateral pulmonary artery as a safe rail.

Percutaneous techniques for treatment of tricuspid valve dysfunction in congenital heart disease - an emerging therapy.

Introduction: Tricuspid valve (TV) dysfunction treatment experiences exponential growth of the interest over the last years. New techniques for percutaneous tricuspid valve treatment are either on the market or in the early stages of development.Areas covered: Deficiency of uniform guideline-based recommendations leads to diverse TV dysfunction treatment options. The current review describes the development of surgical techniques for TV dysfunction in Ebstein's anomaly and transition to a variety of new technologies. Then, the focus is on the potential of percutaneous interventions to reduce the total number of open-heart surgeries in patients with congenital heart disease (CHD) after TV replacement with a bioprosthesis to improve TV function.Expert opinion: TV dysfunction is usually a complex combination of anatomical cardiac features in CHD. Compared to adults with secondary TV dysfunction, CHD patients usually are younger and have experienced several open-heart surgeries at a young age. Therefore, TV dysfunction can affect long-term life expectancy and quality of life significantly. So far, surgery was the gold standard for TV dysfunction treatment. The duration of TV plasty or bioprosthesis is limited, while the risk of re-do operations increases with every procedure. Percutaneous TV implantation may reduce the total number of open-heart surgeries over a patient's life.

Management and Outcomes of Transvenous Pacing Leads in Patients Undergoing Transcatheter Tricuspid Valve Replacement.

OBJECTIVES: The aim of this study was to determine the prevalence of pacemaker lead-related complications following transcatheter tricuspid valve replacement (TTVR). BACKGROUND: The rate of permanent pacemaker implantation following tricuspid valve (TV) surgery is high, and many patients have transvenous leads. The feasibility, safety, and outcomes of subsequently performing TTVR in the setting of transvenous pacemaker leads have not been established. METHODS: The VIVID (Valve-in-Valve International Database) registry was used to review 329 patients who underwent TTVR following TV repair or replacement. Patients were subdivided into 3 cohorts for intergroup comparisons: no lead, epicardial lead, and transvenous lead (entrapped or not entrapped during the TTVR procedure). RESULTS: Of 329 patients who underwent TTVR, 128 (39%) had prior pacing systems in place, 70 with epicardial and 58 with transvenous leads. A total of 31 patients had leads passing through the TV. Three patients had the right ventricular (RV) lead extracted prior to TTVR. The remaining 28 patients had the RV lead entrapped between the transcatheter TV implant and the surgical valve (n = 22) or the repaired TV (n = 6). One patient had displacement of the RV lead during the procedure, and 2 experienced lead failure during follow-up. Overall, there was no significant difference in the cumulative incidences of competing outcomes (death, TV reintervention, TV dysfunction) between patients with and those without pacing leads or entrapped RV leads. CONCLUSIONS: TTVR in the setting of trans-TV pacemaker leads without lead extraction or re-replacement can be performed safely with a low risk for complications, offering an alternative to surgical TV replacement.

Munich Comparative Study: Prospective Long-Term Outcome of the Transcatheter Melody Valve Versus Surgical Pulmonary Bioprosthesis With Up to 12 Years of Follow-Up.

BACKGROUND: Percutaneous pulmonary valve implantation (PPVI) has become an important treatment of right ventricular outflow tract dysfunction. Studies directly comparing the long-term outcome of PPVI with the Melody valve to surgical pulmonary valve replacement (SPVR) are lacking. METHODS: All patients treated with PPVI with the Melody valve and SPVR between January 2006 and December 2018 in our center were enrolled into a database and investigated with a standard follow-up protocol. The current study compares the outcomes in means of survival, reinterventions, infectious endocarditis, and performance of the valves. RESULTS: The study included 452 patients, of whom 241 were treated with PPVI with the Melody valve and 211 patients with SPVR with different types of valves. Median follow-up time was 5.4 years (3 months to 12.5 years), and the total observation was 2449 patient-years. Estimated survival after 10 years was 94% in the Melody group and 92% in the SPVR group (P=0.47). There was no difference in the estimated survival free of surgery on the implanted valve at 10 years (Melody, 87%, versus SPVR, 87%; P=0.54) or in the survival with the originally implanted pulmonary valve (Melody group, 80%; SPVR group, 73%; P=0.46) between both groups. The annualized incidence of infective endocarditis was 1.6% in the Melody group and 0.5% in the SPVR group, and the estimated survival free of endocarditis did not differ significantly between groups (Melody group, 82%; SPVR group, 86%; P=0.082). Survival free of valve replacement because of infective endocarditis was comparable between both groups (Melody, 88%; SPVR, 88%; P=0.35). CONCLUSIONS: PPVI with the Melody valve and SPVR provides similar survival, freedom of reinterventions, and infective endocarditis with or without the need of replacement of the pulmonary valve. Being less invasive, PPVI should be considered a method for treatment for patients with dysfunctional right ventricular outflow tracts.

The Sapien valve provides enough grip to be implanted in pulmonary position without a pre-stent.

BACKGROUND: Pre-stenting is a widely used technique for transcatheter pulmonary valve implantation (TPVI). For the Melody valve a pre-stent creates a reliable and solid landing zone. In contrast to the Melody valve, the Edwards Sapien valve consists of a strong balloon expandable stent designed for implantation in the aortic position. The usage of a Sapien valve in pulmonary position might therefore obviate the need of a pre-stent. METHODS: This retrospective, single centre study reviewed the procedural outcomes of patients receiving the Sapien XT transcatheter valve in pulmonary position without prior implantation of a pre-stent. All consecutive patients with dysfunctional right ventricle to pulmonary artery (RV-PA) conduits or with dysfunctional pulmonary valve treated at the German Heart Centre in Munich were included in this study. RESULTS: We report on successful implantation of a Sapien XT/3 without usage of a pre-stent. CONCLUSIONS: Abandonment of the pre-stent simplified the procedure and reduces the radiation burden for the patients.

Association between patient age at implant and outcomes after transcatheter pulmonary valve replacement in the multicenter Melody valve trials.

OBJECTIVES: To investigate whether age and valve size at implant contribute to outcomes after Melody transcatheter pulmonary valve replacement (TPVR). BACKGROUND: Patient age and valve size at implant contribute to longevity of surgical pulmonary valves. METHODS: All patients discharged with a Melody valve in the pulmonary position, as part of three prospective Melody valve multicenter studies, comprised the study cohort. Acute and time-related outcomes were analyzed according to age: children (≤12 years), adolescents (13-18 years), young adults (19-29 years), and older adults (≥30 years). RESULTS: Successful Melody valve implantation occurred in 49 children, 107 adolescents, 96 young adults, and 57 older adults. Pediatric patients (≤18 years) were more likely to have TPVR for conduit stenosis than adults (62% vs. 44%); children had the smallest conduits. After TPVR, pediatric and adult patients had similar decreases in right ventricular (RV) size by MRI, but adults had improved percentage predicted peak VO2 (58% preimplant to 64% postimplant, p = .02) and FEV1 (69% pre to 71% post, p = .005). Younger age was associated with shorter freedom from RVOT dysfunction, reintervention, and explant. Children had the shortest freedom from endocarditis (p = .041), but all other groups had 5-year freedom from endocarditis of ≥90%. CONCLUSIONS: Younger age was associated with shorter time to RVOT dysfunction, reintervention, and explant after Melody TPVR. Patients ≥13 years of age were at low risk for endocarditis and explant to 5 years. A better understanding of time-related outcomes by age will aid in the comparison of therapeutic options for TPVR candidates. CLINICAL TRIAL REGISTRATION: https://clinicaltrials.gov/ct2/show/NCT00740870 (NCT00740870), https://clinicaltrials.gov/ct2/show/NCT01186692 (NCT01186692), and https://clinicaltrials.gov/ct2/show/NCT00688571 (NCT00688571).

Early postoperative interventional aortic valve closure for severe aortic regurgitation in a neonate after Norwood procedure.

A neonate presented with signs of heart failure early after a Norwood procedure, due to increase of aortic and mitral valve regurgitation. Because repeated surgery was considered risky, we closed the aortic valve by catheter intervention with an Amplatzer Duct Occluder. Aortic regurgitation was abolished almost completely and the child improved. Unfortunately, 2 weeks after discharge, the patient died suddenly.

Mid-Term Valve-Related Outcomes After Transcatheter Tricuspid Valve-in-Valve or Valve-in-Ring Replacement.

BACKGROUND: Transcatheter aortic and pulmonary valves have been used to treat stenosis or regurgitation after prior surgical tricuspid valve (TV) replacement or repair. Little is known about intermediate-term valve-related outcomes after transcatheter tricuspid valve replacement (TTVR), including valve function, thrombus, and endocarditis. OBJECTIVES: The authors sought to evaluate mid-term outcomes in a large cohort of patients who underwent TTVR after surgical TV repair or replacement, with a focus on valve-related outcomes. METHODS: Patients who underwent TTVR after prior surgical TV replacement or repair were collected through an international registry. Time-related outcomes were modeled and risk factors assessed. RESULTS: Data were collected for 306 patients who underwent TTVR from 2008 through 2017 at 80 centers; 52 patients (17%) had a prior history of endocarditis. Patients were followed for a median of 15.9 months after implantation (0.1 to 90 months), with 64% of patients estimated to be alive without TV reintervention or a valve-related event at 3 years. The cumulative 3-year incidence of death, reintervention, and valve-related adverse outcomes (endocarditis, thrombosis, or significant dysfunction) were 17%, 12%, and 8%, respectively. Endocarditis was diagnosed in 8 patients 2 to 29 months after TTVR, for an annualized incidence rate of 1.5% per patient-year (95% confidence interval: 0.45% to 2.5%). An additional 8 patients were diagnosed with clinically relevant valve thrombosis, 3 in the short term, 2 within 2 months, and 3 beyond 6 months. Only 2 of these 8 patients received anticoagulant therapy before thrombus detection (p = 0.13 vs. patients without thrombus). Prior endocarditis was not a risk factor for reintervention, endocarditis, or valve thrombosis, and there was no difference in valve-related outcomes according to TTVR valve type. CONCLUSIONS: TV dysfunction, endocarditis, and leaflet thrombosis were uncommon after TTVR. Patients with prior endocarditis were not at higher risk for endocarditis or other adverse outcomes after TTVR, and endocarditis occurred with similar frequency in different valve types. Though rare, leaflet thrombosis is an important adverse outcome, and further study is necessary to determine the appropriate level of prophylactic therapy after TTVR.

Feasibility, safety and diagnostic impact of endomyocardial biopsies for the diagnosis of myocardial disease in children and adolescents.

AIMS: Endomyocardial biopsies (EMBs) are performed infrequently in children owing to significant past complication rates and controversial discussions about the therapeutic value of results. The objective of this study was to investigate the safety and feasibility of EMBs for suspected myocardial disease in relation to their clinical value. METHODS AND RESULTS: We performed a retrospective multicentre review of the Working Group for Interventional Cardiology of the German Society for Paediatric Cardiology. During three consecutive years, 206 EMBs (84 female/mean age 8.95±6.62 years) were performed and analysed at 15 heart centres. In the majority of cases, biopsies were taken from the right ventricle (RV/89.8%; p<0.001). The overall complication rate was 9.7%, whereas major complications occurred in only 0.97% of cases. Risk factors associated with a higher complication rate were biopsy during the first year of life (20.5%) and from the left ventricle (31.1%) (p<0.05). There was no procedure-related mortality. Treatment was changed in 18.0% of cases based on biopsy results. CONCLUSIONS: Today, endomyocardial biopsies in older children with suspected myocardial disease can be performed safely with a low risk of major complications and mortality, whereas the risk of complications if the biopsy is carried out in the first year of life or taken from the left ventricle remains high.

Retrieval of large Occlutech Figula Flex septal defect occluders using a commercially available bioptome: proof of concept.

OBJECTIVES: This study aimed to develop a method for retrieval of the new meshed nitinol atrial septal defect occluders - Ceraflex and Occlutech. BACKGROUND: The newly developed atrial septal defect occluders have potential benefits considering implantation, but concerns regarding their removal in case of embolisation have been raised. METHODS: Over 21 years, 1449 patients underwent interventional atrial septal defect occlusion in our institution. We reviewed the cases of embolisation of the device, developed a strategy for device removal, and tested it on the benchside and in animal tests. RESULTS: In 11 patients (0.8%), the intended atrial septal defect occlusion was complicated by an embolisation of the device. In contrast to the Amplatzer septal occluders, retrieval of Occlutech devices larger than 16 mm with snare techniques was impossible. In benchside tests, this was confirmed and a new method for removal of large meshed devices was developed. This involved the commercially available Maslanka® biopsy forceps. The feasibility of this technique in vivo was tested in a pig model. During animal tests, using the Maslanka biopsy forceps it was possible to interventionally retrieve embolised Ceraflex and Occlutech devices of different sizes - 10, 16, 30, and 40 mm - into a 12-F sheath. CONCLUSION: It was impossible to retrieve Occlutech and Ceraflex devices larger than 16 mm into a large sheath in vivo and during benchside tests. However, this was feasible on the bench and in vivo using the Maslanka biopsy forceps even with the largest available devices.

Percutaneous retrieval of a partially flared Melody valve.

We report on successful endovascular retrieval of an accidentally flared Melody valve in an adult patient with an indication for percutaneous pulmonary valve implantation. The Melody valve was removed through a 24 F sheath, introduced via the right jugular vein, and the urgent open-heart surgery was avoided.

Percutaneous tricuspid valve implantation in failing bioprosthesis.

Severe tricuspid valve (TV) dysfunction in patients with congenital heart disease (CHD) is usually treated by open heart surgery in relatively young patients. If a valve plasty is not possible, a biological valve is implanted with a limited durability. Due to valve degeneration repeated valve exchanges are necessary in these patients. To expand the lifetime of a bioprosthesis in tricuspid position percutaneous TV implantation (PTVI) was introduced recently. PTVI is a promising new catheter interventional technology. The current review summarizes the indication for PTVI, describes the procedure itself and gives an outlook on medium to long-term results of this catheter intervention. PTVI in patients with severe TV dysfunction is less invasive, safe and effective, if performed by an experienced operator, and may help to reduce the total number of open-heart surgeries during a patient's life time. However, further studies with larger patient numbers and longer follow-up are needed.

Outcomes of Transcatheter Tricuspid Valve-in-Valve Implantation in Patients With Ebstein Anomaly.

We sought to describe the acute results and short- to medium-term durability of transcatheter tricuspid valve-in-valve (TVIV) implantation within surgical bioprostheses among patients with Ebstein anomaly (EA). Cases were identified from a voluntary, multicenter, international registry of 29 institutions that perform TVIV. Demographic, clinical, procedural, and follow-up data were analyzed. Eighty-one patients with EA underwent TVIV from 2008 to 2016. Thirty-four patients (42%) were New York Heart Association (NYHA) class 3/4 at time of TVIV. The most common indication for TVIV was the presence of moderate or severe tricuspid regurgitation (40%). Most patients received a Melody valve (64%). TVIV was ultimately successful in all patients, and there was no procedural mortality. Four patients (5%) developed acute valve thrombosis, 4 patients (5%) developed endocarditis, and 9 patients (11%) developed valve dysfunction not related to thrombosis or endocarditis. Eight patients (10%) underwent reintervention (2 transcatheter, 6 surgical) due to thrombosis (3), endocarditis (2), other valve dysfunction (2), and patient-prosthesis mismatch without valve dysfunction (1). Among 69 patients who were alive without reintervention at latest follow-up, 96% of those with NYHA status reported were class 1/2, a significant improvement from baseline (62% NYHA class 1/2, p <0.001). In conclusion, transcatheter TVIV offers a low-risk, minimally invasive alternative to surgical tricuspid valve re-replacement in patients with EA and a failing tricuspid valve bioprosthesis.

Tricuspid Regurgitation Does Not Impact Right Ventricular Remodeling After Percutaneous Pulmonary Valve Implantation.

OBJECTIVES: This study sought to investigate the impact of tricuspid regurgitation (TR) on right ventricular function after percutaneous pulmonary valve implantation (PPVI). BACKGROUND: PPVI provides a less invasive alternative to surgery in patients with right ventricular-to-pulmonary artery (RV-PA) conduit dysfunction. Recovery of the right ventricle has been described after PPVI for patients with pulmonary stenosis and for those with pulmonary regurgitation. Additional TR enforces RV dysfunction by supplemental volume overload. Limited data are available on the potential of the right ventricle to recover in such a specific hemodynamic situation. METHODS: In a matched cohort study, we compared patients who underwent PPVI with additional TR with those without TR. RESULTS: The degree of TR improved in 83% of the patients. In our patients (n = 36) exercise capacity and right ventricular volume index improved similarly 6 months after PPVI in patients with and without important TR. None of them had significant TR in the long-term follow-up of median 78 months. CONCLUSIONS: PPVI improves not only RV-PA-conduit dysfunction, but also concomitant TR. In patients with a dysfunctional RV-PA conduit and TR, the decision whether to fix TR should be postponed after PPVI.

Aortic rupture during stenting for recurrent aortic coarctation in an adult: live-saving, emergency, NuDEL all-in-one covered stent implantation.

We report a case of successful, life-saving implantation of a covered Cheatham Platinum stent, an all-in-one NuDEL catheter system, in an adult with aortic rupture after bare-metal stenting for re-coarctation of the aorta.

Transcatheter valve implantation for right atrium-to-right ventricle conduit obstruction or regurgitation after modified Björk-fontan procedure.

BACKGROUND: The most common reason for reintervention after a Björk modification of the Fontan procedure, in which the right ventricle (RV) is incorporated into the pulmonary circulation by connecting the right atrial (RA) appendage to the RV directly or with an extra-anatomic graft, is obstruction or regurgitation of the RA-RV connection. Transcatheter implantation of a valved stent is an appealing option for the treatment of RA-RV conduit dysfunction in these patients. In the present study, we assessed early and intermediate results after transcatheter valve implantation within an obstructed or regurgitant RA-RV modified Fontan pathway. METHODS: Through a retrospective multicenter registry, we collected data from 16 patients with a modified Fontan circulation who were treated with percutaneous Melody or Sapien valve implantation for dysfunction of an extra-anatomic RA-RV conduit or valve. RESULTS: All patients had successful and uncomplicated implantation of a Melody (n = 15) or Sapien 3 (n = 1) valve with hemodynamic and, in most cases, clinical improvement. During a median follow-up of 3.3 years, 3 patients died of cardiovascular causes unrelated to the procedure or the valve, and no major valve dysfunction was observed. CONCLUSION: Percutaneous transcatheter valve deployment to treat a dysfunctional RA-RV connection after a Björk modification of the Fontan procedure is a viable alternative to surgery, with low procedural risk, and appears to offer good early and intermediate results.© 2016 Wiley Periodicals, Inc.

Recoarctation After Norwood I Procedure for Hypoplastic Left Heart Syndrome: Impact of Patch Material.

BACKGROUND: The development of recoarctation after the Norwood I procedure is a known complication in patients with hypoplastic left heart syndrome (HLHS). METHODS: We reviewed data on 194 consecutive patients with HLHS who underwent the Norwood I procedure between 2000 and 2015. All patients who survived until the second stage of the procedure were included. Recoarctation was defined by the need for intervention, either catheter based or surgical. The aim of our study was to determine if the patch material used for the initial arch reconstruction had an influence on the development of recoarctation. RESULTS: The study population consisted of 145 patients. The patch material used for aortic arch reconstruction was either a homograft (n = 87), autologous pericardium (n = 23), equine pericardium (n = 28), or other material (n = 7). Recoarctation was documented in 27 patients (18%) at a median time of 4.3 months (range, 1 to 28 months) after completion of Norwood I. Freedom from recoarctation was 85% ± 4%, 86% ± 7%, and 30% ± 22% at 2 years for homograft, autologous pericardium, and equine pericardium, respectively. Thirty-six percent of patients with equine pericardium exhibited recoarctation, significantly more than homograft patch (p < 0.01) or autologous pericardium (p = 0.002). Treatment for recoarctation was percutaneous balloon angioplasty in 19 patients, stent implantation in 3, and operative enlargement of the aortic arch in 5. On univariate analysis, arch reconstruction with equine pericardium was the only risk factor for recoarctation (hazard ratio, 6.0; 95% confidence interval, 2.6-14; p < 0.01). CONCLUSIONS: The patch material used for reconstruction of the aortic arch in HLHS influences the rate of recoarctation following the Norwood I procedure. Equine pericardium cannot be recommended.

Melody transcatheter valve: Histopathology and clinical implications of nine explanted devices.

OBJECTIVES: We examined interventionally implanted valved Melody conduits after surgical explantation by means of histology and immunohistochemistry and matched these findings with clinical data in order to assess in vivo biocompatibility and to identify risk factors for graft failure. METHODS: 9 Melody valves had been implanted in 8 patients (pulmonary n = 7, tricuspid position n = 1). Indication for explantation included significant obstruction in 7 patients and valve insufficiency in 1 patient. 4 of 8 patients had suffered from endocarditis. Mean interval between implantation and explantation was 3.2 (1.8-5.2) years. All explants were worked up using a uniform protocol with fixation in formalin and embedding in methylmethacrylate. RESULTS: All but one valve of the explanted Melody grafts were thin and histologically intact without any pathological findings. Complete neo-endothelialization could be demonstrated by means of immunohistochemistry. All 4 Melody valves from patients with endocarditis showed dense granulocytic infiltrations, 3 of these showed thrombotic material within the valves. CONCLUSION: This report covers the first series of explanted Melody valves from humans applying a uniform protocol for histopathological examination. Good biocompatibility of the Melody valves could be demonstrated after a mid-term follow-up. Factors for graft failure included endocarditis, outgrowth, and residual stenosis. These findings may have significant implications for the implant procedure as well as care of the patients during long-term follow-up.