World Journal for Pediatric and Congenital Heart Surgery current issue

1. To Cool or Not to Cool During Cardiopulmonary Resuscitation

   Therapeutic hypothermia following cardiac arrest improves neurologic outcome following adult ventricular fibrillation (VF) cardiac arrest and perinatal hypoxic ischemic encephalopathy. Evaluation of therapeutic hypothermia in the pediatric cardiac arrest population has been limited thus far to retrospective evaluations and to date there have been no published prospective efficacy trials. Two retrospective pediatric cohort studies showed no benefit from hypothermia compared to usual care. The timing (intra-arrest or post-arrest) and duration of hypothermia may impact patient outcome. While overshoot hypothermia <32°C, hypokalemia, and bradycardia are commonly associated with induced hypothermia, the risks of severe arrhythmia and bleeding are no worse than in normothermic controls. Despite this, rewarming has been identified as a vulnerable time for hypotension and seizure activity and may attribute to worse outcome. The American Heart Association’s current recommendation is "therapeutic hypothermia (32-34°C) may be considered for children who remain comatose after resuscitation from cardiac arrest. It is reasonable for adolescents resuscitated from sudden, witnessed, out-of-hospital VF cardiac arrest." Ongoing research will help delineate whether induced hypothermia following pediatric cardiac arrest improves neurologic outcome.

2. Is the Ross Procedure a Suitable Choice for Aortic Valve Replacement in Children With Rheumatic Aortic Valve Disease?

   Background: Ross procedure is the aortic valve replacement of choice in children. Nonetheless, late autograft reoperation for dilatation and/or regurgitation is concerning. We examine whether Ross procedure is suitable in children with rheumatic fever. Methods: Medical records of 104 children with rheumatic fever who underwent Ross procedure were reviewed (1991-2004). Competing risks methodology determined time-related prevalence and associated factors for two mutually exclusive end states: autograft reoperation and death prior to subsequent reoperation. Results: Mean age was 13.8 ± 2.7, 83 (80%) were males. Hemodynamic dysfunction was primarily regurgitation (n = 92, 88%) and stenosis/mixed (n = 12, 12%). Competing risks analysis showed that in ten years after the Ross procedure, 1% of patients died, 32% underwent autograft reoperation, and 67% were alive and free from reoperation. Ten-year freedom from aortic regurgitation greater than or equal to moderate was 63%. Ten-year freedom from autograft reoperation was 65% for regurgitation versus 90% for stenosis/mixed disease. Risk factors for autograft reoperation were earlier surgery year (PE: 0.26 ± 0.06 per year; P < .001), additional surgery (PE: 0.82 ± 0.39, P = .04), no annular stabilization (PE: 1.21 ± 0.61, P = .05). Ten-year freedom from homograft replacement was 83%. Risk factors were fresh homografts (PE: 1.36 ± 0.71; P = .06) and aortic homografts (PE: 1.15 ± 0.59; P = .05). Ten-year freedom from any cardiac reoperation was 53%. Concomitant cardiac surgery was risk factor (PE: 1.37 ± 0.47; P = .004). Conclusions: Ross procedure in children with rheumatic fever is associated with excellent survival but results are plagued by aortic regurgitation and frequent autograft reoperation. Risk factors include preoperative regurgitation, concomitant surgery, dilated annulus, and earlier surgery era. Better patient selection in later era has mitigated autograft reoperation risk. Continued, improved candidate selection, along with modifications in autograft implantation and root/sinotubular stabilization techniques, may further decrease late autograft failure.

3. Design Control Requirements for Medical Device Development

   Medical devices used in the United States must comply with federal regulations established to ensure that specified requirements have been met. The article will focus on 1 of 14 elements of the Quality System Regulation (QSR)—Design Controls. A high-level overview of these design control requirements is provided to increase awareness of the device development process and provide a basis for mutual understanding for continued dialogue with end users. Design control requirements were established by the US Food and Drug Administration (FDA) as an element of the QSR in 1996. Device manufacturers are required to have a quality management system (QMS) to ensure their devices are safe and effective. The QMS is established by writing operating procedures to achieve consistent application of the methods used to control quality and comply with regulatory requirements. The FDA has the responsibility to audit device manufacturers for compliance with the regulation. The requirements of the QSR and the resulting device design control procedures lend themselves to what is commonly known as the waterfall development process. This iterative process results in documented evidence that is defined in the QSR as the Design History File. This record of development is essential for managing the product life cycle. The elements and purpose of the design control process will be presented to illuminate today’s development environment. Conclusion: Collaboration between device developers and the practitioner is essential for improving clinical outcomes and reducing time to market of innovative devices.

4. Surgical Decision Making in Neonatal Ebstein's Anomaly: An Algorithmic Approach Based on 48 Consecutive Neonates

   Objective: There is currently no consensus of opinion regarding the optimal surgical management of Ebstein’s anomaly (EA) in neonates and young infants. Reported early mortality rates range from 25% to 100%. In this study, we present an algorithm for choosing the best management option for neonates with EA based on analysis of our experience. Patients and Methods: From 1994 to June, 2011, 48 neonates with a diagnosis of EA were managed by the same surgical team. Of these, two died before intervention; the remaining 46 either were managed medically initially (n = 20) or underwent surgical intervention during the neonatal period (n = 26) or early infancy (n = 9). Results: The mean weight was 3.6 ± 1.7 kg (1.9-8.6) and mean follow-up time was 6.3 ± 4.5 years (0.2-16). Of the 20 patients initially managed medically, 11 remain well without intervention and nine required complete repair in infancy, with 100% survival. Of the 26 neonatal operations, 23 (88%) were complete biventricular repairs, 1 Starnes’ palliation, and two Blalock–Taussig shunts (BTSs) ± pulmonary valvotomy. Among those having a two-ventricle repair, anatomic pulmonary atresia (APA) was a risk factor for early mortality (46.1%, 6 of 13) compared with those without pulmonary atresia (EA/no-PA; 10%, 1 of 10), P < .05. Conclusions: Most symptomatic neonates with EA will require early operation. For those with APA and mild tricuspid regurgitation (TR), a modified BTS and reduction atrioplasty may be the best initial option. For those with functional pulmonary atresia and severe TR and pulmonary regurgitation, ligation of the main pulmonary artery and placement of a BTS may provide the best initial palliation. For the rest, either a biventricular repair or a single-ventricle palliation is indicated.

5. Challenges at the Bedside With ECMO and VAD

   Patients on circulatory support can be the source of multiple challenges including optimizing the circuit for specific congenital heart lesions, troubleshooting circuit failures, transporting patients on the circuit, anticoagulation and bleeding, transitioning to more mobile ventricular assist device, listing for thoracic organ transplantation, weaning from the circuit, and educating the patient and family about mechanical support. These challenges ideally require a specialized multidisciplinary team, which includes anesthesiologists, child life specialists, extracorporeal membrane oxygenation (ECMO) specialists, intensivists, nurses, nutritionists, perfusionists, pharmacists, respiratory therapists, social workers, and surgeons.