Richard Chard

Right ventricular dysfunction in congenitally corrected transposition of the great arteries

Although right ventricular (RV) dysfunction is an important complication in subjects with congenitally corrected transposition of the great arteries, its pathogenesis is poorly understood. We assessed the role of RV myocardial perfusion and found perfusion defects at rest in all 20 patients, involving 4.6 +/- 2.3 of a total of 12 segments; the extent of the resting perfusion defects correlated inversely with the RV ejection fraction.

Levosimendan for low cardiac output: a pediatric experience.

This was a retrospective observational study in a pediatric intensive care unit, in which 19 patients received levosimendan. There were no adverse events attributable to levosimendan and no instances where the clinical condition worsened after administration. Arterial lactate levels decreased significantly following levosimendan administration during cardiopulmonary bypass for anticipated low cardiac output. In those with established low cardiac output, trends toward improved hemodynamics were seen, with heart rate reduction, an increase in mean blood pressure, a reduction in arterial lactate, and reduced conventional inotrope use. Levosimendan was safely used in a small number of pediatric patients with established low cardiac output state who demonstrated improved hemodynamics and tissue perfusion, with a tendency to reduced conventional inotrope usage, and this warrants its evaluation as an inotrope in the pediatric population.

Outcomes following surgery for congenital heart disease in low-birthweight infants

Aim:u2003 To describe cardiac surgery, survival and outcomes for low‐birthweight (≤2500u2003g) infants undergoing surgery for congenital heart disease.

Five-year Analysis of Operative Mortality and Neonatal Outcomes in Congenital Heart Disease

BACKGROUNDnWe sought to compare overall mortality with neonatal outcomes over a five year period to define risk factors for mortality and service development priorities.nnnMETHODSnA retrospective cohort study of surgical outcomes following repair or palliation of structural congenital heart defects January 2005-2010. We defined mortality according to contemporary international guidelines and classified surgical procedures using the Risk Adjustment in Congenital Heart Surgery (RACHS-1) score. The effect of age and weight at operation on mortality and annual variation in case-complexity and surgeon case-mix were assessed. Subgroup analysis was performed in patients who were ≤30 days at operation (neonates).nnnRESULTSnOverall mortality within 30 days of operation or prior to hospital discharge was 1.3 and 1.9%, respectively. Mortality was higher in neonates (6.8%) and low birth weight infants (≤2.5kg) (12.1%). Mortality was similar in bypass versus non-bypass procedures (odds ratio 0.74, p=0.425). Annual mortality rates were consistent despite a marked increase in case-complexity. Neonates overall required longer periods of intensive care support and were more likely to suffer serious complications compared to older children. Age, weight and RACHS-1 score were independent risk factors for mortality on multivariate analysis. In neonates undergoing bypass procedures, only RACHS-1 score was a significant risk factor.nnnCONCLUSIONSnThis study provides an accurate and contemporary audit of mortality risk associated with congenital heart surgery. Outcomes compare favourably to international benchmarks but highlight the risks of morbidity and mortality associated with neonatal cardiac surgery.

Recombinant Activated Factor VII Following Pediatric Cardiac Surgery

Objective: Review the use of recombinant activated Factor VII following cardiac surgery. Specifically, we sought to define our current therapeutic practice indications and outcomes to assess the impact of recombinant activated factor VII on postoperative bleeding. Design: Retrospective case series. Setting: The study was conducted at the University affiliated pediatric intensive care unit. Patients and participants: All postcardiac surgical patients who received recombinant activated Factor VII between June 2002 and July 2006. Results: Cardiac surgery requiring cardiopulmonary bypass was performed on 1010 children during this period. In all, 25 (2.5%) children received recombinant activated factor VII for excessive bleeding. A single dose (180 μg/kg) of recombinant activated factor VII was given to 11 patients and 2 doses of 180 μg/kg to 14 patients. Intercostal drain losses were reduced from 12 (6.7-20.8) mL/kg/h to 3 (1-4.1) mL/kg/h, P = .018 following 1 dose of recombinant activated factor VII. In those receiving 2 doses; initial losses were 19.1 (7.5-31.7) mL/kg/h, after the first dose were 7.5 (3.6-13.7) mL/kg/h, P = .046, and after the second dose were 2 (1-2.9) mL/kg/h, P = .008. The plasma prothrombin time decreased in both the 1 dose, P = .003 and 2 dose, P = .009 groups. The activated partial thromboplastin time also decreased in the 1 dose group, P = .007 and 2 dose group, P = .03. There were no side effects attributable to recombinant activated factor VII. Annual rates of return to the operating theatre for excessive bleeding were coincidentally reduced in association with the routine use of recombinant activated factor VII from 4.3% to 1.5%, P = .019. Conclusions: Hemostasis occurred in 25 postoperative pediatric cardiac patients after recombinant activated Factor VII was given. In this setting, once conventional hemostatic therapy was optimized, recombinant activated Factor VII 180 μg/kg initially with intercostal losses greater than 10 mL/kg/h and a repeat dose after 2 hours if losses remained greater than 5 mL/kg/h was effective. No complications were found to have occurred and there was a coincidental reduction in annual returns to theatre for excessive bleeding.

Use of sildenafil and nitric oxide in the management of hypoxemia owing to pulmonary arteriovenous fistulas after total cavopulmonary connection

Use of sildenafil and nitric oxide in the management of hypoxemia owing to pulmonary arteriovenous fistulas after total cavopulmonary connection Sameer Bhate, MCh DNB(CVTS), Michael Rossiter-Thornton, BMedSc(Hons), Stephen G. Cooper, MB, ChB, FRACP, Jonathan Gillis, PhD, FRACP, Andrew D. Cole, BAppSci(Hons), Gary S. Sholler, MBBS, FRACP, Richard B. Chard, BDS, MBBS, FRACS, and David S. Winlaw, MD, FRACS, Sydney, Australia

Management errors in adults with congenital heart disease: prevalence, sources, and consequences

AimsnImproved survival has resulted in increasing numbers and complexity of adults with congenital heart disease (ACHD). International guidelines recommend specialized care but many patients are still not managed at dedicated ACHD centres. This study analysed referral sources and appropriateness of management for patients referred to our tertiary ACHD Centre over the past 3u2009years.nnnMethods and resultsnWe compared differences in care between patients referred from paediatric/ACHD-trained vs. general adult cardiologists, according to Adherence (A) or Non-Adherence (NA) with published guidelines. Non-Adherent cases were graded according to the severity of adverse outcome or risk of adverse outcome. Of 309 consecutively referred patients (28u2009±u200914u2009years, 51% male), 134 (43%) were from general cardiologists (19% highly complex CHD) and 115 (37%) were from paediatric cardiology or ACHD specialists (33% highly complex CHD). Sixty referrals (20%) were from other medical teams and of those, 31 had been lost to follow-up. Guideline deviations were more common in referrals from general compared to CHD-trained cardiologists (Pu2009<u20090.001). Of general cardiology referrals, 49 (37%) were NA; 18 had catastrophic or major complications (nu2009=u20092, 16 respectively). In contrast, only 12 (10%) of the paediatric/ACHD referrals were NA, but none of these were catastrophic and only 3 were major. Simple, moderate, and highly complex CHD patients were at increased risk of adverse outcome when not under specialized CHD cardiology care (Pu2009=u20090.04, 0.009, and 0.002, respectively).nnnConclusionnNon-adherence with guidelines was common in the ACHD population, and this frequently resulted in important adverse clinical consequences. These problems were more likely in patients who had not been receiving specialized CHD care. Configuring healthcare systems to optimize whole of life care for this growing population is essential.

Right ventricular outflow tract enlargement prior to pulmonary valve replacement is associated with poorer structural and functional outcomes, in adults with repaired Tetralogy of Fallot.

BACKGROUNDnPulmonary valve replacement (PVR) is commonly performed late after Tetralogy of Fallot (TOF) repair. We examined the effects of PVR on cardiac structure, function and exercise capacity in adults with repaired TOF.nnnMETHODSnEighteen adult patients with repaired TOF and severe pulmonary regurgitation (PR) with right ventricular (RV) dilatation requiring PVR for clinical reasons (age; 25±8 years) were recruited to undergo cardiac MRI (1.5T) and cardiopulmonary exercise testing before and 14±3 months after PVR.nnnRESULTSnReduced indexed RV end-diastolic volume (RVEDVi; 186±32mL/m(2) pre-op vs 114±20mL/m(2) post-op, p<0.001) was observed after PVR. Normalisation of RVEDVi (≤108mL/m(2)) was achieved in only seven of 18 patients. Pre-PVR RVEDVi correlated with post-operative change in RVEDVi (change=-72.1±20.4mL/m(2), r=-0.815, p<0.001). Exercise capacity remained high-normal post-PVR (% predicted maximal workload: 93±16% vs 91±12%, p=0.5). Regional RV volumes were assessed; RV outflow tract (RVOT) volumes were compared to the RV muscular corpus. Large pre-PVR RVOT volumes correlated negatively with post-surgical RV ejection fraction, peak VO2 and delta VO2 at anaerobic threshold (p<0.05 for all).nnnCONCLUSIONSnNormalisation of RV volume is unlikely to be achieved above a pre-PVR RVEDVi of 165mL/m(2) or more. In particular, an enlarged RVOT prior to PVR predicts suboptimal structural and functional outcomes.

Surgical and Hybrid Ablation of Atrial Fibrillation

Atrial fibrillation (AF) is the most common arrhythmia in humans and is known to be associated with an increased risk of stroke, dementia, heart failure and mortality. Non-pharmacological therapy with ablation using either surgical or percutaneous techniques is recommended in drug refractory AF. Early attempts to devise procedures to ablate AF and restore sinus rhythm culminated with the Cox-Maze procedure, the first truly successful procedure. Since then, ablation surgery has been conducted predominately as a concomitant procedure. The Cox Maze procedure is complex and technically demanding and has, therefore, been extensively modified with new techniques for creating the linear ablation lines, new lesion sets, minimally invasive surgical techniques and most recently hybrid surgical-catheter ablation techniques. Surgical ablation techniques result in a marked reduction in atrial fibrillation when compared to conventional therapy with only a small increase in procedural risk. However, further research is required to more accurately quantify those benefits and to determine the optimal lesion sets, specific to the underlying arrhythmia mechanism and the optimal energy sources for ablation.

Hoarseness and Chest Pain in Eisenmenger Syndrome With Pulmonary Artery Aneurysm

A 62-year-old woman presented with a 4-month history of persistent and progressively worsening left upper chest pain despite analgesia. One month prior, she had noticed a hoarseness of voice. Physical examination at the time revealed cyanosis, clubbing of hands and feet, and pulmonary regurgitation murmur but no right ventricular failure. There was prominent bulging of her rib cage over the left upper precordium. Cardiac catheterization at 12 years of age had confirmed Eisenmenger syndrome (with mean pulmonary arterial pressure of 86 mm Hg) due to an atrial septal defect and significant shunt reversal. In recent years, she had progressive dilation of her pulmonary arterial trunk despite phosphodiesterase inhibitor treatment for 6 years.nnA transthoracic echocardiogram revealed an aneurysmal pulmonary arterial trunk with severely elevated right ventricular systolic pressure at 84 mm Hg and right ventricular hypertrophy typical of Eisenmenger syndrome (Figure 1). Computed tomography pulmonary angiogram revealed a giant main pulmonary arterial aneurysm with maximal dimension of 7.2 cm but no radiographic evidence of dissection, leakage, or rupture …