Fetal Echocardiography is Useful for Screening Fetuses with a Family History of Cardiomyopathy.

We screened all fetal echocardiograms performed at our institution for the past 5 years for the indication of family history of cardiomyopathy. Twenty-six patients were identified who had fetal echocardiograms performed due to a family history of cardiomyopathy. Three out of 26 patients (11.5%) had findings of decreased ventricular function and dilation consistent with cardiomyopathy. All who had cardiomyopathy on fetal echocardiography had parents with genetic mutations (2 maternal, 1 paternal), including one mother who had a cardiac transplant at age 8 for dilated cardiomyopathy. All 3 affected infants had prenatal planning for high level care and were transferred to our facility immediately after birth for cardiology evaluation and management. 2 patients required inotropic support in the newborn period. One patient was transplanted at age 2 months. One patient required ECMO support for one week and initially recovered, but subsequently required mechanical support and listing for heart transplant. We recommend patients with a strong family history of cardiomyopathy in either parent, especially those with known genetic mutations associated with cardiomyopathy, have fetal echocardiograms performed.

Clinical characterisation of a novel SCN5A variant associated with progressive malignant arrhythmia and dilated cardiomyopathy.

INTRODUCTION: The SCN5A gene is implicated in many arrhythmogenic and cardiomyopathic processes. We identified a novel SCN5A variant in a family with significant segregation in individuals affected with progressive sinus and atrioventricular nodal disease, atrial arrhythmia, dilated cardiomyopathy, and early sudden cardiac arrest. METHODS: A patient pedigree was created following the clinical evaluation of three affected individuals, two monozygotic twins and a paternal half-brother, which lead to the evaluation of a paternal half-sister (four siblings with the same father and three mothers) all of whom experienced varying degrees of atrial arrhythmias, conduction disease, and dilated cardiomyopathy in addition to a paternal history of unexplained death in his 50s with similar autopsy findings. The index male underwent sequencing of 58 genes associated with cardiomyopathies. Sanger sequencing was used to provide data for bases with insufficient coverage and for bases in some known regions of genomic segmental duplications. All clinically significant and novel variants were confirmed by independent Sanger sequencing. RESULTS: All relatives tested were shown to have the same SCN5A variant of unknown significance (p. Asp197His) and the monozygotic twins shared a co-occurring NEXN (p. Glu575*). Segregation analysis demonstrates likely pathogenic trait for the SCN5A variant with an additional possible role for the NEXN variant in combination. CONCLUSIONS: There is compelling clinical evidence suggesting that the SCN5A variant p. Asp197His may be re-classified as likely pathogenic based on the segregation analysis of our family of interest. Molecular mechanism studies are pending.

Converting Fontan-Björk to 1.5- or 2-Ventricle Circulation.

Patients with tricuspid atresia and ventricular septal defect have in the past occasionally undergone a Fontan with "Björk" modification to create a connection between the right atrium and the right ventricular outflow tract. Although rarely performed now, patients with this physiology often face severe complications requiring reintervention. We hypothesize that surgical conversion to a 2-ventricle or 1.5-ventricle circulation can improve hemodynamics, clinical status, and thus increase time to transplant. We present 2 successful cases to illustrate this idea.

Successful treatment of disseminated adenovirus infection with cidofovir and intravenous immunoglobulin in an infant following heart transplant.

For most patients, adenoviruses cause few acute health concerns and are often self-limiting. Patients who are immunocompromised or immunosuppressed, however, are at risk for disseminated adenovirus and suffer high morbidity and mortality, without well-defined treatment options. We report the case of a 9-month-old boy who was successfully treated for disseminated adenovirus infection with intravenous immunoglobulin and cidofovir 3 months post heart transplant, tailored to serum adenoviral load and clinical response. We emphasise the importance of early identification, monitoring, and a potentially novel treatment in the paediatric cardiac transplant population with disseminated adenovirus infection.

Management of Complications Caused by a Massive Left Ventricle Tumor in a Neonate.

We report the case of a neonate born with a giant fibroma occupying the entirety of her left ventricle. Owing to the extensive resection, her postoperative course was complicated by severely diminished left ventricular function and complete heart block necessitating extracorporeal support. Ultimately, cardiac resynchronization therapy was used, after which the infant's ventricular function gradually improved and she was successfully discharged to home.

Strategies to Prevent Cast Formation in Patients with Plastic Bronchitis Undergoing Heart Transplantation.

Plastic bronchitis, a rare complication after Fontan palliation, carries a high morbidity and mortality risk. Heart transplantation is an effective treatment option, but casts may occur in the early post-operative period. We present a case series detailing peri-operative management strategies to minimize morbidity and mortality related to plastic bronchitis in patients undergoing heart transplantation. Patient 1 received no treatment pre-, intra-, or post-transplant for prevention of bronchial casts and developed severe respiratory acidosis 18 h following transplant. Emergent bronchoscopy was performed and a large obstructive cast was removed. The patient recovered and received inhaled tissue plasminogen activator (tPA) for 5 days. Patient 2 received inhaled tPA before, during, and for 5 days after transplantation and no bronchial casts developed. Patient 3 underwent intraoperative bronchoscopy just prior to implantation revealing no casts. The patient underwent non-urgent, preemptive bronchoscopy on post-transplant days 1, 3, and 4, removing several partially obstructive bronchial blood clots/casts, with no casts thereafter. Heart transplantation results in eventual resolution of plastic bronchitis. Residual bronchial casts can still be problematic in the peri-operative period. Airway clearance with inhaled tPA or bronchoscopy may prevent the need for prolonged mechanical ventilation and reduce post-operative morbidity in this unique population.

Congenital Pulmonary Vein Stenosis: Encouraging Mid-term Outcome.

Congenital pulmonary vein stenosis (PVS) is a rare entity with limited outcome literature. Multiple interventional approaches have evolved including surgical and catheterization techniques. Our objective is to report our center experience and to compare short-term and mid-term outcomes among these therapeutic modalities. Retrospective study on 23 patients (n = 23) with PVS that required intervention over the last 13 years (2000-2013). Patients were divided into three groups based on type of initial intervention. Of these, 10 (43.5%) had balloon angioplasty, 3 (13.0 %) had surgical dilation, and 10 (43.5%) had surgical marsupialization. Mortality and number of re-interventions were our primary outcomes. Mean age at diagnosis was 10.9 ± 18.4 months. Mean age at initial intervention was 14.5 ± 18.0 months. Mean pre- and post-initial intervention PVS gradients were 9.2 ± 3.4 and 3.4 ± 2.2 mmHg, respectively. Mean survival time and re-intervention-free survival time were 4.8 ± 4.0 and 2.8 ± 3.4 years. No statistical significance was found between the interventions with respect to survival time (p = 0.52) and re-intervention free time (p = 0.78). High initial pre- and post-intervention gradients were significantly associated with re-intervention-free survival (p = 0.01 and p = 0.03, respectively). Patients with bilateral disease have increased mortality (p = 0.01) and decreased 5-year survival (p = 0.009) compared to patients with unilateral disease irrespective of type of intervention. No statistically significant difference in mortality or re-intervention rate was present among these different therapeutic modalities. This study has the longest follow-up so far reported in the current literature (58 months) with overall survival of 78%.

Severe airway obstruction from a bronchial cast after cardiac transplantation.

Plastic bronchitis is a rare and difficult to treat disease process in patients with congenital heart disease. Cardiac transplantation has been used increasingly to reverse this process, especially in single ventricle physiology. This case report demonstrates a foreseeable complication after cardiac transplantation in such a patient.

Valved bovine jugular vein conduits for right ventricular outflow tract reconstruction in children: an attractive alternative to pulmonary homograft.

BACKGROUND: Pulmonary homografts (PH) have been the preferred valved conduits for right ventricular outflow tract (RVOT) reconstruction in the US since the mid-1980s. Although PHs have worked well for Ross patients, many PH extracardiac conduits used for congenital heart surgery suffer from degeneration and develop regurgitation and obstruction within months after implantation and require replacement within 4 to 6 years. Recently a valve-containing bovine jugular vein (Contegra, Medtronic, Inc, Minneapolis, MN) was introduced for clinical trials for a variety of patients requiring RVOT reconstruction. METHODS: The early results of RVOT reconstruction utilizing the Contegra conduit were retrospectively analyzed in 62 patients. This series consisted of 9 newborns with truncus arteriosus, 39 patients with failed PHs, 6 with pulmonary atresia and 2 with tetralogy of Fallot with absent pulmonary valve, 2 with transposition of great arteries with ventricular septal defect and pulmonary stenosis, and 4 undergoing a Ross procedure. The patients ages ranged from 2 weeks to 18 years (mean, 7.3 +/- 6.0 years) and weights were from 2 to 83 kg (mean, 28.1 +/- 22.3 kg). The Contegra conduit sizes varied in diameter between 12 and 22 mm (mean, 18.2 +/- 4.1 mm). RESULTS: There were two early (3%) and four (7%) late deaths and none of them was conduit related. There has been one conduit explantation, and seven patients have required reinterventions to relieve stenosis at or beyond the distal anastomosis of the conduit to pulmonary artery bifurcation (8 of 60; 13%). Six of the 7 patients had balloon dilatation of the branch pulmonary arteries for preexisting stenosis. One patient developed distal anastomotic stenosis that did not yield to balloon angioplasty and she underwent surgical patch arterioplasty of the distal anastomosis. The interval from conduit implantation to reintervention ranged from 3 to 27 months (mean, 11.1 +/- 7.8 months). Of these, three patients required placement of a stent in the left (n = 1) or both branch pulmonary arteries (n = 2). During the short to intermediate follow-up in our series we have not observed, on echocardiography, shrinkage of the Contegra as we and others have reported with PHs. CONCLUSIONS: The Contegra conduit offers a promising alternative for RVOT reconstruction. Early hemodynamic performance compares favorably with PHs. Clinical advantages are greater availability in sizes from 12 to 22 mm and natural continuity between the valve and conduit that allows proximal infundibular shaping without additional materials. The price of the bovine jugular venous valve is approximately one-half that of many PHs in the US. Short-term freedom from dysfunction is at least as good as PHs. Long-term durability must be determined for this new conduit. The Contegra conduit is currently our conduit of choice for RVOT reconstruction in infants, children, and young adults.

Value of plasma B-type natriuretic peptide as a marker for rejection in pediatric heart transplant recipients.

We analyzed 211 consecutive plasma B-type natriuretic peptide (BNP) measurements in 59 pediatric heart transplant patients along with echocardiographic and right ventricular endomyocardial biopsy samples. Patients with a biopsy specimen negative for rejection had significantly lower BNP levels than those patients with a biopsy positive (p