Sergio Picardo

Extracardiac Fontan operation for complex cardiac anomalies: Seven years' experience

METHODS Between 1988 and 1995, 60 patients with complex cardiac anomalies underwent a total extracardiac cavopulmonary connection, a combination of a bidirectional cavopulmonary anastomosis with an extracardiac conduit interposition between the inferior vena cava and pulmonary arteries, except in one patient in whom direct anastomosis was possible. In 40 patients the total extracardiac cavopulmonary connection followed preliminary bidirectional cavopulmonary anastomosis, associated with a modified Damus-Kaye-Stansel anastomosis in 16. The conduits were constructed of Dacron fabric (n = 34), homografts (n = 3), and polytetrafluoroethylene (n = 22). RESULTS Total early failure rate was 15% (n = 9). Six patients died, and three more had conduit takedown owing to pulmonary artery stenosis and hypoplasia (n = 2) and severe atrioventricular valve regurgitation (n = 1). Two other patients required anastomosis revision owing to stricture. In a mean follow-up of 48 months (6 to 86 months) there were no late deaths (actuarial 5-year survival 88% +/- 4%); 52 of 54 patients are in New York Heart Association class I or II. Two patients required pulmonary artery balloon dilation or stent implantation, or both, after total extracardiac cavopulmonary connection. Late tachyarrhythmias were detected in four of 54 patients: two had sick sinus syndrome with flutter necessitating a pacemaker implantation and two had recurrent flutter (actuarial 5-year arrhythmia-free rate 92% +/- 4%). Conduit patency was evaluated by serial magnetic resonance imaging studies. Preliminary data showed a 17.8% +/- 7.6% mean reduction in conduit internal diameter during the first 6 months after total extracardiac cavopulmonary connection, with no progression over the next 5 years. CONCLUSION These results demonstrate that the total extracardiac cavopulmonary connection provides good early and midterm results and may reduce the prevalence of late arrhythmias in patients undergoing the Fontan operation.

Usefulness of magnetic resonance imaging for diagnosis of acute myocarditis in infants and children, and comparison with endomyocardial biopsy

The diagnosis of acute myocarditis has traditionally been based on the results of endomyocardial biopsy.1 This invasive procedure, particularly in children, may present major complications and is performed only at a limited number of centers. Recent studies have demonstrated the reliability of magnetic resonance imaging (MRI) in tissue characterization of cardiac allograft rejection2–4 that is histologically identical to acute myocarditis.5 The aim of this study was to test the sensitivity and specificity of MRI versus endomyocardial biopsy in the diagnosis of acute myocarditis in children.

High-dose fenoldopam reduces postoperative neutrophil gelatinase-associated lipocaline and cystatin C levels in pediatric cardiac surgery

IntroductionThe aim of the study was to evaluate the effects of high-dose fenoldopam, a selective dopamine-1 receptor, on renal function and organ perfusion during cardiopulmonary bypass (CPB) in infants with congenital heart disease (CHD).MethodsA prospective single-center randomized double-blind controlled trial was conducted in a pediatric cardiac surgery department. We randomized infants younger than 1 year with CHD and biventricular anatomy (with exclusion of isolated ventricular and atrial septal defect) to receive blindly a continuous infusion of fenoldopam at 1 μg/kg/min or placebo during CPB. Perioperative urinary and plasma levels of neutrophil gelatinase-associated lipocaline (NGAL), cystatin C (CysC), and creatinine were measured to assess renal injury after CPB.ResultsWe enrolled 80 patients: 40 received fenoldopam (group F) during CPB, and 40 received placebo (group P). A significant increase of urinary NGAL and CysC levels from baseline to intensive care unit (ICU) admission followed by restoration of normal values after 12 hours was observed in both groups. However, urinary NGAL and CysC values were significantly reduced at the end of surgery and 12 hours after ICU admission (uNGAL only) in group F compared with group P (P = 0.025 and 0.039, respectively). Plasma NGAL and CysC tended to increase from baseline to ICU admission in both groups, but they were not significantly different between the two groups. No differences were observed on urinary and plasma creatinine levels and on urine output between the two groups. Acute kidney injury (AKI) incidence in the postoperative period, as indicated by pRIFLE classification (pediatric score indicating Risk, Injury, Failure, Loss of function, and End-stage kidney disease level of renal damage) was 50% in group F and 72% in group P (P = 0.08; odds ratio (OR), 0.38; 95% confidence interval (CI), 0.14 to 1.02). A significant reduction in diuretics (furosemide) and vasodilators (phentolamine) administration was observed in group F (P = 0.0085; OR, 0.22; 95% CI, 0.07 to 0.7).ConclusionsThe treatment with high-dose fenoldopam during CPB in pediatric patients undergoing cardiac surgery for CHD with biventricular anatomy significantly decreased urinary levels of NGAL and CysC and reduced the use of diuretics and vasodilators during CPB.Trial registrationClinical Trial.Gov NCT00982527.

Fenoldopam in newborn patients undergoing cardiopulmonary bypass: controlled clinical trial

We determined if low dose fenoldopam in neonates already receiving conventional diuretics improves urine output, fluid balance, acute kidney injury incidence (AKI) and time to extubation. A prospective controlled clinical trial in a pediatric cardiac intensive care unit on 40 neonates undergoing cardiac surgery with cardiopulmonary bypass, excluding simple ventricular septal defect and atrial septal defect. Fenoldopam was infused at a low dose of 0.1 microg/kg/min soon after anesthesia induction and infusion prolonged for 72 h in 20 patients. Twenty neonates with standardized perioperative therapy except fenoldopam administration served as controls. Demographic, hemodynamic, daily urine output, creatinine, creatinine clearance, serum and urinary sodium and potassium were recorded. Inotropic score (IS) was calculated as a surrogate for the degree of hemodynamic impairment. Low dose fenoldopam infusion did not show beneficial effects in renal function. The treatment did not significantly affect IS value, AKI incidence, fluid balance control, time to sternal closure, time to extubation and time to intensive care unit discharge. Low dose fenoldopam in neonates undergoing cardiac surgery with CPB did not produce effects on urine output, fluid balance and AKI incidence. Fenoldopam was well tolerated and did not negatively affect hemodynamics and vasopressor support.

Mechanical Assist Device as a Bridge to Heart Transplantation in Children Less Than 10 Kilograms

BACKGROUND Despite the remarkable advances with the use of ventricular assist devices (VAD) in adults, pneumatic pulsatile support in children is still limited. We report a retrospective review of our experience in very small children (<10 kg of body weight). METHODS Ten consecutive children weighing less than 10 kg were offered mechanical support with Berlin Heart (Berlin Heart AG, Berlin, Germany) as a bridge to heart transplant from March 2002 to March 2010. RESULTS The median patient age was 10.4 months (38 days to 2.2 years). The median patient weight was 6.4 kg (2.9 to 10 kg). Prior to VAD implantation, all children were managed by multiple intravenous inotropes and mechanical ventilation (8) or extracorporeal membrane oxygenation (2). The median pre-VAD pulmonary vascular resistance index was 5.7 Woods units/m(2). Three patients required biventricular mechanical support, but in all other cases a single left VAD proved sufficient. The median duration of VAD support was 61 days (2 to 168 days). Four deaths occurred; from stroke in three and sepsis in one. Five patients were successfully bridged to heart transplantation after a median duration of mechanical support of 89 days (37 to 168 days) and another is still waiting a suitable organ after 77 days of VAD support. There were no complications related to postoperative bleeding. Five patients required at least one pump change. Of 5 patients undergoing heart transplant, 3 developed an extremely elevated (>60%) panel reactive antibody by enzyme-linked immunosorbent assay, confirmed by Luminex (Luminex Corp, Austin, TX). All 3 experienced at least one acute episode of rejection in the first month after heart transplant, needing plasmapheresis. The survival rate after heart transplantation was 100% with a median follow-up of 7.5 months. CONCLUSIONS Mechanical support in very small children with end-stage heart failure is an effective strategy of bridge to heart transplantation with a reasonable mortality rate. The high rate of complications suggests to optimize indications and timing of VAD implantation.

Balloon-expandable metallic stents in the management of tracheomalacia in neonates

Tracheomalacia is a challenging problem after operations for certain congenital heart malformations in neonates and infants. 1 It may often prevent the patients from being weaned from mechanical ventilation. Management of this condition remains difficult. Many surgical approaches have been suggested, although none of them is universally accepted. 2 Conversely, a major role could be played by stent implantation at the level of the malacic segment. However, both silicone stents and self-expanding metallic stents present major technical or physiologic problems in pediatric patients. 35 This article reports on our preliminary experience with the use of endovascular balloon-expandable metallic stents in the treatment of neonatal tracheomalacia after surgical repair of congenital heart malformations. Patient population. During 1993, three patients (Table I) were subjected to implantation of a balloon-expandable metallic stent at the airway level. The stent was used to treat tracheobronchial malacia that caused failure to wean from assisted ventilation after operations for congenital cardiovascular malformations. In each case, informed parental consent was obtained before stent implantation. Technique. The morphologic features of the malacic segment were evaluated by tracheography during spontaneous respiration. Peak respiratory pressure and pulmonary compliance were measured before and after stent implantation by a Capnomac Ultima monitor (Datex Medical Instrumentation, Tewksbury, Mass.). Endovascular balloon-expandable Palmaz-Schatz stents (Johnson & Johnson, New Brunswick, N.J.), 128 mm long, were used to support the tracheomalacic segment. The stent was mounted on the Lo-Bow (Mallinckrodt Medical, Inc., St. Louis, Mo.) 6 mm balloon guidewire (0.035 inch) and positioned, under fluoroscopic guidance, at the level of the malacic segment through the endotracheal tube used for mechanical ventilation. After the endotracheal tube had been withdrawn as far as possible, mechanical ventilation was briefly suspended and the balloon rapidly inflated to expand the stent. Statistical analysis. Morphologic and functional data were expressed as mean values _-2-1 standard deviation. Statistical analysis was performed by the paired Students t test. Results. Balloon-expandable stent implantation was simply, quickly, and successfully performed in all cases.

Acute kidney injury in an infant after cardiopulmonary bypass.

The infant who develops acute kidney injury (AKI) after cardiopulmonary bypass (CPB) surgery presents unique challenges and opportunities to the clinician and to the investigator interested in the study of AKI pathophysiology. Infants do not have many of the comorbid conditions that confound CPB outcome studies of adults. Because the timing of the AKI event is known in this clinical setting, collaboration between cardiology intensivists, nephrologists, and perfusion technologists is essential to minimize the impact of CPB on the kidney. Early institution of ultrafiltration in the operating room and renal replacement therapy in the postoperative period may decrease the proinflammatory milieu and its resultant systemic effects. In addition, early initiation of renal replacement therapy to prevent fluid overload may result in improved infant outcomes.

Impact of severe sepsis on serum and urinary biomarkers of acute kidney injury in critically ill children: an observational study.

Background/Aims: We hypothesized that sepsis could have an impact on the sensitivity of serum and urinary neutrophil gelatinase-associated lipocalin (NGAL) and cystatin C (CysC) for acute kidney injury (AKI) diagnosis in critically ill children. Methods: Serum NGAL (sNGAL) and urinary NGAL (uNGAL) and CysC were measured daily in the first 48 h from pediatric intensive care unit admission in 11 consecutive critically ill children with severe sepsis; a single measurement was made in a population of 10 healthy controls undergoing minor ambulatory surgery to exclude possible biases in the laboratory methods. Results: uNGAL, serum CysC (sCysC), and urinary CysC (uCysC) levels were significantly increased in patients with septic AKI compared with septic patients without AKI, while sNGAL levels were not significantly different between septic patients with and without AKI. Median serum creatinine levels did not show significant differences between AKI and non-AKI patients. Conclusions: uNGAL, sCysC and uCysC were not altered by sepsis and were good predictors of AKI. In a septic state, sNGAL alone did not discriminate patients with AKI from those without AKI.

Renal replacement therapy in neonates with congenital heart disease.

BACKGROUND The acute renal failure (ARF) incidence in pediatric cardiac surgery intensive care unit (ICU) ranges from 5 to 20% of patients. In particular, clinical features of neonatal ARF are mostly represented by fluid retention, anasarca and only slight creatinine increase; this is the reason why medical strategies to prevent and manage ARF have limited efficacy and early optimization of renal replacement therapy (RRT) plays a key role in the outcome of cardiopathic patients. METHODS Data on neonates admitted to our ICU were prospectively collected over a 6-month period and analysis of patients with ARF analyzed. Indications for RRT were oligoanuria (urine output less than 0.5 ml/kg/h for more than 4 h) and/or a need for additional ultrafiltration in edematous patients despite aggressive diuretic therapy. RESULTS Incidence of ARF and need for RRT were equivalent and occurred in 10% of admitted neonates. Eleven patients of 12 were treated by peritoneal dialysis (PD) as only RRT strategy. PD allowed ultrafiltration to range between 5 and 20 ml/h with a negative balance of up to 200 ml over 24 h. Creatinine clearance achieved by PD ranged from 2 to 10 ml/min/1.73 m2. We reported a 16% mortality in RRT patients. CONCLUSION PD is a safe and adequate strategy to support ARF in neonates with congenital heart disease. Fluid balance control is easily optimized by this therapy whereas solute control reaches acceptable levels.

Cerebral NIRS as a marker of superior vena cava oxygen saturation in neonates with congenital heart disease

Objectives:  To investigate the correlation between cerebral near‐infrared spectroscopy (NIRS) (rSO2c) and superior vena cava venous oxygen saturation (ScvO2) in newborn patients with congenital heart disease (CHD).