Bjorn Cools

Infective endocarditis of a transcatheter pulmonary valve in comparison with surgical implants

Background Melody valved stents (Medtronic Inc, Minneapolis, Minnesota, USA) have become a very competitive therapeutic option for pulmonary valve replacement in patients with congenital heart disease. After adequate prestenting of the right ventricular outflow tract (RVOT) Melody valved stents have a good medium term functional result but are exposed to infective endocarditis (IE). Patients and methods Retrospective study of tertiary centre Congenital Heart Disease database; to compare incidence of IE in three different types of valved conduits in RVOT: Melody valved stent, cryopreserved homograft (European Homograft Bank) and Contegra graft (Medtronic Inc). Results Between 1989 and 2013, 738 conduits were implanted in 677 patients. 107 Melody valved stents were implanted in 107 patients; IE occurred in 8 (7.5%) patients during a follow-up of 2.0 years (IQR 2.4 years, range 0.3–7.8 years). 577 Homografts were implanted in 517 patients; IE occurred in 14 patients (2.4%) during a median follow-up of 6.5 years (IQR 9.2 years; range 0.1–23.7 years). Finally, 54 Contegra grafts were implanted in 53 patients; 11 patients (20.4%) had IE during a follow-up of 8.8 years (IQR 7.7 years; range 0.2–3.5 years). Survival free of IE by Kaplan–Meier for homografts was 98.7% at 5 years and 97.3% at 10 years; for Contegra 87.8% at 5 years and 77.3% at 10 years and for Melody 84.9% at 5 years (log-rank test; p<0.001). Conclusions The Contegra conduit and Melody valved stents have a significantly higher incidence of IE than homografts. IE is a significant threat for long-term conduit function.

Off-label use of percutaneous pulmonary valved stents in the right ventricular outflow tract: time to rewrite the label?

Percutaneous pulmonary valve implantation is now considered feasible and safe. “Native” right ventricular outflow tract (RVOT), small diameter conduits (<16 mm) and relatively large RVOT with a dynamic outflow aneurysm are currently considered off‐label uses. Extending indications creates concerns of safety, ethics, reimbursement, and liability.

Percutaneous pulmonary valve implantation for free pulmonary regurgitation following conduit-free surgery of the right ventricular outflow tract

INTRODUCTION Pulmonary regurgitation (PR) following surgery of the right ventricular outflow tract (RVOT) is not innocent and leads to significant right heart dysfunction over time. Recent studies have demonstrated that percutaneous valves can be implanted in conduit free outflow tracts with good outcomes. OBJECTIVES To evaluate in patients with severe PR--anticipated to require future pulmonary valve replacement--the feasibility and safety of pre-stenting dilated non-stenotic patched conduit-free right ventricular outflow tracts before excessive dilation occurs, followed by percutaneous pulmonary valve implantation (PPVI). PATIENTS AND METHODS Twenty seven patients were evaluated, but only 23 were deemed suitable based on the presence of an adequate retention zone ≤ 24 mm defined by semi-compliant balloon interrogation of the RVOT. A 2 step procedure was performed: first the landing zone was prepared by deploying a bare stent, followed 2 months later by valve implantation. RESULTS RVOT pre-stenting with an open cell bare metal stent (Andrastent XXL range) was performed at a median age of 13.0 years (range: 6.0-44.9) with a median weight of 44.3 kg (range: 20.0-88.0). Ninety six percent (22/23) of patients proceeded to PPVI a median of 2.4 months (range: 1.4-3.4) after initial pre-stent placement. Twenty one Melody valves and one 26 mm Edwards SAPIEN™ valve were implanted. Complications consisted of embolization of prestent (n = 1), scrunching (n = 4) and mild stent dislocation (n = 2). During follow-up, no stent fractures were observed and right ventricular dimensions decreased significantly. CONCLUSIONS Post-surgical conduit-free non-stenotic RVOT with free pulmonary regurgitation can be treated percutaneously with a valved stent if anatomical (predominantly size) criteria are met. In experienced hands, the technique is feasible with low morbidity.

Transventricular balloon dilation and stenting of the RVOT in small infants with tetralogy of fallot with pulmonary atresia

The management of small infants with tetralogy of Fallot (TOF) with pulmonary atresia (PA) and hypoplastic pulmonary arteries can be very challenging.

Design and feasibility of “PREMATurity as predictor of children's Cardiovascular–renal Health” (PREMATCH): A pilot study

Abstract The microvasculature and macrovasculature undergo extensive, organ-specific perinatal maturation. Multiple studies show associations between low birth weight and subsequent cardiovascular dysfunction in adulthood, suggesting that extreme preterm birth interferes with this maturation process. Therefore, we designed PREMATCH (PREMATurity as predictor of Cardiovascular–renal Health) to phenotype the microcirculation and macrocirculation during childhood in former preterm infants. A well-characterized cohort of former extreme preterm birth survivors and gender- and age-matched controls (aged 8–13 years) will be investigated for microvascular and macrovascular structure and function. In addition to cognitive performance and anthropometrics, we will investigate (i) the microvascular structure and function by endothelial function (photoplethysmography), sublingual capillary glycocalyx function (sidestream dark field imaging) and retinal structure (diameters of arterioles and venules); and (ii) the macrovascular phenotype by cardiac and renal ultrasound, repeated blood pressure measurements and arterial pulse-wave recordings. The PREMATCH study is unique in its design, and ongoing recruitment demonstrates excellent feasibility. The expectation is that the results of this study will identify risk factors during childhood for subsequent cardiovascular–renal disease in the adult life of former preterm infants, while further analysis on mediators in neonatal life of this cardiovascular–renal outcome may provide new information on perinatal risk factors. Trial registration: ClinicalTrials.gov identifier: NCT02147457.

Cracking a tricuspid perimount bioprosthesis to optimize a second transcatheter sapien valve-in-valve placement

Bioprosthetic valves degenerate over time. Transcatheter valve‐in‐valve procedures have become an attractive alternative to surgery. However, every valve increasingly diminishes the diameter of the valvar orifice. We report a 12‐year‐old female who had a previous transcatheter tricuspid valve‐in‐valve procedure; cracking the ring of a Carpentier Edwards Perimount valve by means of an ultrahigh pressure balloon allowed implantation of a further larger percutaneous valve. The advantage of this novel approach permits enlarging the inner valve diameter and may facilitate future interventions and prolong time to surgery.

Hybrid stenting of aortic coarctation in very low birth weight premature infant

A very low birth weight infant with severe aortic coarctation developed progressive left ventricular dysfunction and pulmonary overflow with hemorrhage, while receiving prostaglandins. To avoid morbidity from conventional surgery or percutaneous intervention, a two‐step strategy was performed at a weight of 970 g. First vascular access was obtained through sternotomy: a 3/8 mm coronary stent was deployed through a 4 French sheath in the ascending aorta; the arterial duct was clipped. At the age of 5 months, the stent was removed and the aortic arch reconstructed with an end‐to‐end anastomosis through lateral thoracotomy. This strategy was not associated with morbidity typical for premature infants with congenital heart disease.

When coronary arteries need systolic pressure: surgical considerations

OBJECTIVES Patients with pulmonary atresia and intact ventricular septum (PA-IVS) may have coronary sinusoids connected to a hypertensive right ventricle. Coronary perfusion may then completely depend on the right ventricular systolic pressure wave; decompression of the right ventricle can be deleterious in these patients. This study was set to investigate the treatment strategies and outcomes of patients with coronary sinusoids. METHODS National multicentre retrospective analysis over 15 years (1985-2010) in a population of ~10.2 million people. All patients with PA-IVS and coronary sinusoids were identified from local databases. All angiograms, echocardiograms, surgical reports and outcome data were reviewed. RESULTS Thirty patients were identified. Right ventricular-dependent coronary circulation was present in nine patients (30%). A systemic-to-pulmonary artery shunt was created in 23 patients (77%) at a median age of 13.0 days (range: 1-479). A bidirectional Glenn was performed in 20 children at a median age of 7.8 months (range: 2.1-112.9) and 11 children proceeded to a Fontan repair at a median age of 3.6 years (range: 2.1-19.6). Pulmonary valve perforation and angioplasty were performed in six children and in three a simultaneous decompression procedure was also done. Ten patients died (33%). Four died at the time of systemic-to-pulmonary artery shunt and three during the bidirectional Glenn shunt. In all these patients myocardial ischaemia was reported. CONCLUSIONS Mortality in PA-IVS with sinusoids is high. Right ventricular coronary dependence may lead to early death if the right ventricular systolic pressure wave is interrupted. Adequate understanding of the underlying pathology and pathophysiology is essential before attempting any procedure in this subgroup of children.

Xenon as an adjuvant to sevoflurane anesthesia in children younger than 4 years of age, undergoing interventional or diagnostic cardiac catheterization: A randomized controlled clinical trial

Xenon has repeatedly been demonstrated to have only minimal hemodynamic side effects when compared to other anesthetics. Moreover, in experimental models, xenon was found to be neuroprotective and devoid of developmental neurotoxicity. These properties could render xenon attractive for the anesthesia in neonates and infants with congenital heart disease. However, experience with xenon anesthesia in children is scarce.

Medium term follow-up after percutaneous pulmonary valve replacement with the Melody® valve

Introduction Data on long term function of the Melody valve are scarce. Patients and methods: single institution; results of percutaneous pulmonary valve implantation (PPVI) from 2006 to 2014. The function of the valved conduit was analyzed by Doppler echocardiography. Annual Chest X-ray after implant and permanent screening for events (e.g. Endocarditis). Results 112 Melody valves were implanted in 111 patients; mean age 19.3 years (4.5–81.6). No pre-stenting of the RVOT was performed (n = 4) at first. In the next 107 patients pre-stenting was always performed. In 82 patients 1 pre-stent, 18 patients 2, in 6 patients 3 stents and 1 patient 4 stents were used. The Melody stent was dilated up to 24 mm (n = 4), 22 mm (n = 72), 20 mm (n = 28) and 18 mm (n = 6). When stenotic, the Doppler gradient reduced from 67.0 mm Hg (SD 13.9) to 18.9 mm Hg (SD 10.4) (p < 0.001); pulmonary regurgitation (PR) was reduced from median 3.5/4 (range 0–4/4) to none or trivial (p < 0.001). There was no significant change in RVOT peak velocity at 5 years (p = 0.122) nor PR (p = 0.835). Type 1 stent fractures were observed in 1/4 non-pre-stented patients and in 5/107 pre-stented (p < 0.05). Endocarditis occurred in 8/112 valves; freedom of endocarditis was 85% at 5 years. In 2 patients early surgical replacement was necessary. Six were sterilized with antibiotic treatment; 2 patients required re-stenting and re-PPVI due to residual gradient. Conclusion Adequate pre-stenting of the RVOT before PPVI nearly abolishes or delays stent fracture. Cusp function is well preserved in mid-term follow-up; endocarditis is a threat.