Prosthetic Conduit Endocarditis With Nontuberculous Mycobacteria in a Child: Associated With the Water Mattress and Heater Chiller Unit.

There is a growing body of literature on infection with nontuberculous mycobacteria (NTM) associated with heater chiller units in the cardiac surgery population. We report a pediatric case undergoing reoperation for early right ventricle-to-pulmonary artery conduit stenosis. A successful outcome was achieved following excision of the infected conduit and six-week antibiotic treatment. To our knowledge, there is only one other pediatric cardiac case reported in the literature. Similar to the recently reported cases of infection associated with Mycobacterium chimaera in predominately adult patients after cardiac bypass surgery, we hypothesize that water-containing devices such as the heater chiller unit and water blanket acted as a reservoir for other NTM. With increasing awareness of NTM, we analyzed the 2015-2016 culture data on our fleet of eight heater chiller units. We identified an association between persistent positive cultures and the connection of a water mattress to the heater chiller unit circuit. This led us to abandoning the use of the mattress in pediatric cardiac surgery.

Natural history of a systemic right ventricle.

The natural history of a systemic right ventricle after an atrial switch procedure has yet to be fully characterised. We describe the case of the longest surviving patient at our institution who underwent a Mustard Baffle correction for dextro-transposition of great arteries in childhood. Over following decades he was reviewed regularly with deteriorating systemic right ventricle function. At around 50 years of age he developed worsening heart failure on maximal medical therapy. He was subsequently assessed for cardiac transplantation which he underwent successfully at the age of 55 years.

Antenatal Detection of Treatable Critical Congenital Heart Disease Is Associated with Lower Morbidity and Mortality.

OBJECTIVE: To establish the impact that timing of diagnosis and place of birth have on neonatal outcomes in those with readily treatable critical congenital heart disease. STUDY DESIGN: This was a population-based study with a complete national cohort of live-born infants with transposition of the great arteries and aortic arch obstruction in New Zealand between 2006 and 2014. Timing of diagnosis, place of birth, survival to surgery, in-hospital events, and neonatal mortality were reviewed. Live births with a gestation of ≥35 weeks and without associated major extracardiac anomalies were included for analysis. RESULTS: A total of 166 live-born infants with transposition of the great arteries and 87 with aortic arch obstruction were included. Antenatal detection increased from 32% in the first 3 years to 47% in the last 3 years (P = .05). During the same period, neonatal mortality decreased from 9% to 1% (P = .02). No deaths occurred after surgical intervention. An antenatal diagnosis was associated with decreased mortality (1/97 [1%] vs 11/156 [7%]; P = .03) and birth outside the surgical center was associated with increased risk of mortality (11/147 [7%] vs 1/106 [1%]; P = .02). Those with an antenatal diagnosis required fewer hours of mechanical ventilation (P = .02) and had shorter durations of hospital stay (P = .05) compared with those diagnosed >48 hours after birth. CONCLUSIONS: The mortality risk for transposition of the great arteries and critical aortic arch obstruction is greatest before cardiac surgery. Improved antenatal detection allowing delivery at a surgical center is associated with reduced mortality.

Ventricular Function Before and After Surgery for Isolated and Combined Regurgitation in the Young.

BACKGROUND: Chronic mitral and aortic regurgitation (MR and AR) are associated with progressive contractile dysfunction. In the young, the risk of left ventricle (LV) dysfunction after operation for isolated and combined AR and MR is poorly defined. We aimed to compare LV mechanics in children and young adults with isolated and combined AR and MR, and identify risk factors for LV dysfunction after valve surgery. METHODS: Echocardiograms from children and young adults undergoing surgery for isolated severe AR (group I, n = 14), MR (group II, n = 21), or combined AR and MR (group III, n = 13), before and up to 18 months after surgery were compared with a normal population (n = 89). Normalized measures of LV geometry and mechanics were expressed as z scores. RESULTS: Before surgery all groups had LV dilatation, while groups I and III had afterload elevation and LV dysfunction. After operation LV dysfunction was more common in group III than in groups I and II (11 [84.5%] vs 5 [35.7%] vs 12 [57.1%], p = 0.04). The preoperative end-systolic volume z score predicted LV dysfunction after surgery in group I and II patients (p = 0.047, area under the curve = 0.75) but not in group III, where moderate LV dysfunction was related to the preoperative stress velocity index (-2.6 with vs -1.1 without, p = 0.04). CONCLUSIONS: Left ventricular mechanics in combined AR and MR closely resemble those of AR. End-systolic volume predicts postoperative LV dysfunction in patients with isolated valve regurgitation, while those with combined disease were at high risk of postoperative LV dysfunction.

Normalized end-systolic volume and pre-load reserve predict ventricular dysfunction following surgery for aortic regurgitation independent of body size.

Pre-operative end-systolic volume (ESV) is predictive of outcome after surgery for severe aortic regurgitation. ESV is influenced by body size and reflects function and afterload, but not pre-load. Left ventricular (LV) chamber size and function were measured in 40 patients (ages 10 to 64 years) by echocardiography before and 7 months after operation and expressed as z-scores in addition to simple indexing. A functional pre-load index, a marker of pre-load reserve, was calculated. Independent risk factors for post-operative LV dysfunction included higher post-operative ESV z-score (odds ratio [OR]: 3.3, p = 0.006) and lower functional pre-load index (OR: 0.3, p = 0.03). ESV per square meter had similar power to the ESV z-score. The ESV uncorrected for body size underestimated risk in smaller patients and overestimated risk in larger patients (p < 0.002). Pre-load reserve is an independent risk factor for LV dysfunction after aortic valve surgery in patients with severe aortic regurgitation. Failure to correct ESV for body size introduces systematic bias to risk assessment.

Outcomes using predominantly single-stage approach to interrupted aortic arch and associated defects.

BACKGROUND: Neonatal repair of interrupted aortic arch (IAA) involves an early choice between a single-stage or two-stage strategy. Risk factors for each are not yet fully investigated, especially as they relate to major associated cardiac malformations. We aimed to assess the outcome of neonates undergoing biventricular repair of IAA and associated congenital heart defects. METHODS: Preoperative assessment, operative management, and outcome were retrospectively reviewed for 18 consecutive patients undergoing biventricular IAA repair at Starship Children's Hospital from 2000 to 2005. RESULTS: Seventeen patients underwent a single-stage procedure and one patient weighing 970 g underwent a two-stage procedure. All but one had a ventricular septal defect. Major associated cardiac defects were present in 7 and included aortopulmonary window (1), truncus arteriosus (3), transposition of the great arteries (1), and aortic valve atresia (2). Those with major associated cardiac defects had longer procedural times but similar early mortality and intensive care unit and hospital stay. One patient required a pacemaker for complete heart block. Mean follow-up was 4.5 years with one late death and all survivors reporting normal functional status. Developmental delay was present in 5 (27%), 4 of whom had 22q deletion. Late reoperation was required in 4, including two Konno procedures and two pulmonary conduit changes. CONCLUSIONS: A good functional outcome and low reoperation rate can be achieved with a single-stage repair regardless of the presence of major additional cardiac abnormalities. Neonates with risk factors such as low birth weight and prematurity require an individualized approach.

Giant congenital coronary artery aneurysm in pulmonary atresia with intact septum.

Congenital coronary artery fistula is frequently associated with pulmonary atresia and intact ventricular septum (PA/IVS). Aneurysmal dilatation is rare, and can be complicated by rupture, distal thrombi and myocardial ischaemia.

Cardiac transplantation and aortic coarctation repair in severe heart failure.

A 37-year-old man presented with severe dilated cardiomyopathy secondary to occult aortic coarctation. He was successfully managed with combined orthotopic heart transplantation and aortic coarctation repair.

Cardiac pacing in the management of severe pallid breath-holding attacks.

Reflex anoxic seizures (pallid breath-holding attacks) can be managed with reassurance in the majority of individuals. In a minority of cases where frequent syncopal and seizure activity occurs, intervention needs to be considered. We report a case of a 19-month infant with a history of severe reflex anoxic seizures who underwent pacemaker insertion with a spectacular result, with complete termination of syncope and seizures, and improvement in quality of life for the patient and family. A literature review of the safety and effectiveness of pacemaker insertion is also presented to support its use as a treatment option for this condition.