Prem Venugopal

Hybrid procedure as an alternative to surgical palliation of high-risk infants with hypoplastic left heart syndrome and its variants

OBJECTIVES Despite improvements in the surgical management of neonates with the hypoplastic left heart syndrome and its variants, there is a subset of children who have a high predicted mortality. We have analyzed and report our results with the hybrid approach in the management of these high-risk patients. METHODS Children identified by our selection criteria underwent the initial hybrid procedure performed in the catheterization laboratory. This consists of surgical banding of the branch pulmonary arteries and stenting of the arterial duct. This was followed 3 to 6 months later by the combined stage I and II Norwood operation or biventricular repair. RESULTS Between December 2005 and May 2008, 21 neonates were selected for the hybrid procedure, of whom 16 had typical hypoplastic left heart syndrome. The remaining 5 neonates had severe aortic stenosis with borderline left ventricular dimensions or poor left ventricular function at presentation. Four neonates had a virtually intact interatrial septum and required urgent intervention immediately after birth. There were 6 deaths as inpatients or up to 30 days after the procedure and 1 interstage death before the combined stage I and II operation. Thus far, of 12 babies who have undergone the next operation, 9 have had the combined stage I and II operation and 3 have had a biventricular repair. Two of these 12 babies have died after the combined stage I and II operation. CONCLUSION A hybrid approach may be a valuable alternative to the management of high-risk neonates with hypoplastic left heart syndrome and its variants.

Delayed Presentation of a Post-Traumatic Left Ventricular Pseudoaneurysm in a Child

Left ventricular pseudoaneurysms can occur after myocardial infarction or trauma, but are extremely rare in pediatric patients. We present a case of post-traumatic left ventricular pseudoaneurysm, in whom the causative event was some time before the acute clinical deterioration. The 9-year-old boy had repeated presentations for chest pain and lethargy for some months prior to admission. The report describes an effective primary suture repair.

Multiple Ventricular Septal Defects: A New Strategy

Introduction: A multicenter prospective study was conducted to evaluate a new strategy for multiple Ventricular Septal Defects (VSDs). Materials and Methods: From 2004 to 2012 17 consecutive children (3 premature, 14 infants), mean age 3.2 months (9 days–9 months), mean body weight 4.2 kg (3.1–6.1 kg), with multiple VSDs underwent Pulmonary Artery Banding (PAB) with an adjustable FloWatch-PAB®. Associated cardiac anomalies included patent ductus arteriosus (1), aortic coarctation (2), hypoplastic aortic arch (2), and left isomerism (3). Five patients (5/17 = 29.4%) required pre-operative mechanical ventilation, with a mean duration of 64 days (7–240 days) Results: There were no early or late deaths during a mean follow-up of 48 months (7–98 months), with either FloWatch removal or last observation as end-points. FloWatch-PAB® adjustments were required in all patients: a mean of 4.8 times/patient (2–9) to tighten the PAB, and a mean of 1.1 times/patient (0–3) to release the PAB with the patient’s growth. After a mean interval of 29 months (8–69 months) 10/17 (59%) patients underwent re-operation: 7/10 PAB removal, with closure of a remaining unrestrictive VSD in 6 (peri-membranous in 3 patients, mid-muscular in 2, and inlet in 1) and Damus–Kaye–Stansel, bi-directional Glenn, and atrial septectomy in 1; 3/9 patients required only PAB removal. All muscular multiple VSDs had closed in all 10 patients. PA reconstruction was required in 1/10 patient. In 5/7 of the remaining patients with the PAB still in situ, all muscular VSDs had already closed. The only 2 patients with persistent muscular multiple VSDs are the 2 patients with the shortest follow-up. Conclusion: This reproducible new strategy with an adjustable PAB simplifies the management of infants with multiple VSDs and provides the following advantages: (a) good results (0% mortality), delayed surgery with a high incidence (15/17 = 88%) of spontaneous closure of multiple muscular VSDs, and facilitated closure of residual unrestrictive VSD (peri-membranous, mid-muscular, or inlet) at an older age and higher body weight; PAB with FloWatch-PAB® and its subsequent removal can potentially be the only procedure required for Swiss cheese multiple VSDs without an associated peri-membranous unrestrictive VSD.

Complete atrioventricular septal defect: outcome of pulmonary artery banding improved by adjustable device.

OBJECTIVE We sought to evaluate pulmonary artery banding in infants with complete atrioventricular septal defects. METHODS From 2000 to 2009, 20 infants with complete atrioventricular septal defects underwent pulmonary artery banding because of unsuitable anatomy (unbalanced ventricles, associated lesions, or both) or clinical condition (infection, chronic lung disease, or noncardiac malformation). Patients were divided into 2 groups: the conventional PAB group (n = 13 [65%]; mean age, 74 ± 56 days [range, 6-187 days]; mean weight, 3.3 ± 1.1 kg [range, 2.1-5.8 kg]) and the FloWatch-PAB group (n = 7 [35%]; mean age, 111 ± 40 days [range, 81-187 days]; mean weight, 4.3 ± 1.2 kg [range, 3.2-6.1 kg]). There was no statistical difference in age or weight. Preoperative mechanical ventilation was required in 3 (23%) of 13 infants in the conventional PAB group and 5 (71%) of 7 infants in the FloWatch-PAB group (P < .05). RESULTS Ten (77%) of 13 infants in the conventional PAB group died versus 0 (0%) of 7 infants in the FloWatch-PAB group (P < .001). Sternal closure was delayed in 6 (46%) of 13 infants in the conventional PAB group and 0 (0%) of 7 infants in the FloWatch-PAB group (P < .05). The mean duration of mechanical ventilation, intensive care unit stay, and hospital stay was significantly longer (P < .05) in the conventional PAB group than in the FloWatch-PAB group (21 ± 17 days [range, 4-61 days] vs 3 ± 2 days [range, 1-8 days], 22 ± 18 days [range, 5-61 days] vs 7 ± 6 days [range, 2-21 days], and 54 ± 12 days [range, 40-71 days] vs 29 ± 25 days [range, 9-81 days], respectively). Left atrioventricular valve regurgitation increased (mild to moderate) in 2 infants in the conventional PAB group and decreased (severe to moderate) in 2 infants in the FloWatch-PAB group. Six of 10 survivors (1 in the conventional PAB group and 5 in the FloWatch-PAB group) underwent pulmonary artery debanding and repair after a median interval of 125 days (range, 34-871 days); 4 of 10 are awaiting repair. CONCLUSIONS In selected patients with complete atrioventricular septal defects, pulmonary artery banding followed by late repair is a viable alternative strategy. In our study the FloWatch-PAB device resulted in improved survival and made later repair possible in a better clinical state.

Histologic Evaluation of Explanted Tissue-Engineered Bovine Pericardium (CardioCel)

CardioCel is a bovine pericardium that is subjected to a novel anticalcification tissue-engineering process. We present the histopathologic findings of human explants of CardioCel that were used in operations for congenital heart disease in children. Six explants were identified from 140 patients undergoing CardioCel implants from October 2012 to March 2015. CardioCel explants were evaluated histologically using hematoxylin and eosin, Masson trichrome, and immunohistochemical staining. A variable inflammatory response was seen in the surrounding native tissue, but not within the CardioCel graft in any of the explants. A neointimal layer of varying thickness developed on the visceral surface of 5 CardioCel explants with endothelialization of the longest duration explant. A granulation tissue layer developed on the parietal surface of the graft (consistently thicker than the neointima). Maintained collagen fiber architecture (laminated) and variable fibroblastic invasion (which increased with the age of the implant) were identified in all 6 cases. Scattered capillary vessels were noted in the majority of the explants with new collagen fibers in one, suggesting early remodeling. Calcium was seen in 1 explant at the interface of the graft and inflammatory response on its parietal surface. Evidence of graft remodeling was noted in the majority of the explants without inflammatory cells or calcification within the explanted graft material. A noticeable feature was the differential thickness of the host reaction to the parietal compared with the visceral surface of the graft. We will continue to evaluate CardioCel as a cardiovascular substitute for extracardiac and intracardiac reconstructions.

Transection with pseudoaneurysm formation of the pulmonary trunk after placement of an adjustable pulmonary artery banding device (FloWatch-PAB) in a patient with residual muscular ventricular septal defect.

FIGURE 1. Two-dimensional echocardiographic analysis with Doppler scann artery (PA) band device in the lumen of the pulmonary artery. RA, Right atrium From Congenital Heart Surgery, Guy’s & St Thomas NHS Foundation Trust, London, United Kingdom. Disclosures: None. Received for publication Jan 20, 2009; revisions received Feb 7, 2009; accepted for publication March 2, 2009; available ahead of print May 18, 2009. Address for reprints: Prem S. Venugopal, MCh, FRCS, Congenital Heart Surgery, Guy’s & St Thomas NHS Foundation Trust, 20, Stangate, Royal St, London SE1 7EQ, United Kingdom (E-mail: vpremsundar@gmail.com). J Thorac Cardiovasc Surg 2010;139:e103-4 0022-5223/

Outcome of a repair-oriented strategy for the aortic valve in children.

36.00 Copyright 2010 by The American Association for Thoracic Surgery doi:10.1016/j.jtcvs.2009.03.002

Creating a Controlled Arterio-Venous Shunt by Reversing the Extracorporeal Membrane Oxygenation Blood Flow: A Strategy for Weaning Patients Off Veno-Arterial Extracorporeal Membrane Oxygenation

Background: We sought to evaluate the mid-term results of a repair-oriented strategy of the aortic valve in children. Methods: Between February 2007 and November 2011, we performed 39 aortic valve repairs in children. Median age and weight at surgery were 5.5 years (3 days-18 years) and 16.7 kg (2.7-83.5), respectively. A total of 11 (28%) patients had one or more prior surgical or interventional cardiologic procedures. Median intensive care unit and hospital stay were two (1-96) and five (3-96) days, respectively. Median and cumulative follow-up were 12.7 months (15 days-64 months) and 48.9 patient-years, respectively. Results: There were 3 (7.7%) early deaths all in patients undergoing additional complex cardiac procedures. Two (5.1%) patients required early surgical revision. Twenty-six (66%) patients had isolated or mixed aortic stenosis. The median gradient reduced from 62.4 (range 16-144) to 17.6 mm Hg (range 0-51.8), postoperatively (P = .02). At last follow-up, the median gradient remained largely unchanged at 21.1 mm Hg (0-49; P = .02). Twenty-six (66%) patients had isolated or mixed aortic valve regurgitation (mild in 8 [20%], moderate in 15 [38%], and severe in 6 ([15%] patients). The degree of aortic regurgitation improved in all patients with moderate or severe aortic regurgitation (P = .04). At last follow-up, two patients had moderate aortic regurgitation. Kaplan Meier freedom from reintervention in the survivors was 95% at three years. Conclusions: A repair-oriented strategy for the aortic valve in children has satisfactory early and mid-term results and remains a promising management option in children with aortic valve disease.

Concomitant congenital heart defect repair and Nuss procedure for pectus excavatum

Objectives: To assess whether reversing the veno-arterial extracorporeal membrane oxygenation blood flow (thereby creating a controlled arterio-venous shunt) can be used to wean children off extracorporeal membrane oxygenation. The standard practice for weaning patients off VA extracorporeal membrane oxygenation is to gradually reduce the blood flows delivered through the extracorporeal membrane oxygenation pump to a minimum level followed by either insertion of an “arterio-venous bridge” and clamping of the blood flow to the patient or direct decannulation. “Pump controlled retrograde flow trial off” is a technique where the revolutions in the centrifugal pump are reduced to the point where the patient will drive the blood retrograde through the extracorporeal membrane oxygenation circuit, effectively turning the circuit into a controlled arterio-venous shunt. The revolutions per minute control the amount of shunt flow. This eliminates any cardiorespiratory support the extracorporeal membrane oxygenation circuit may provide to the patient. Design: Feasibility study. Setting: Pediatric intensive care. Patients: Extracorporeal membrane oxygenation-dependent pediatric patients, who were ready for weaning, and possible separation from extracorporeal membrane oxygenation entered the trial. Intervention: Pump controlled retrograde flow trial off. Measurement and Main Results: During 2016, pump controlled retrograde flow trial off was used in 17 patients, for a total of 23 episodes. One episode was unsuccessful in a patient with a body weight of 2.2 kg, where cardiac output was insufficient to provide blood flow to both body and extracorporeal membrane oxygenation circuit, though from 2.8 kg body weight upward, the technique was tolerated. The duration of pump controlled retrograde flow trial off was 15 minutes to 2.5 hours. Five cases led to a continuation of the extracorporeal membrane oxygenation run, as they were not ready to be decannulated. Fifteen patients were decannulated after the pump controlled retrograde flow trial off. No patient needed to be recommenced on extracorporeal membrane oxygenation after decannulation. Conclusions: Pump controlled retrograde flow trial off is an easy to use and easily reversible technique to assess patient readiness for separation from extracorporeal membrane oxygenation. Given pump controlled retrograde flow trial off can easily be stopped and—in our experience—is not associated with complications, it lowers the threshold to attempt coming off extracorporeal membrane oxygenation and facilitates accurate assessment of whether a patient will need further ongoing extracorporeal membrane oxygenation support.

Late embolization to the aortic arch of an Amplatzer Device used to occlude a baffle leak

The combination of complex congenital cardiac anomalies and pectus excavatum represents a technical challenge. Most concomitant repairs have been performed in adult patients. We report the uncomplicated concomitant repair of double-outlet right ventricle with absent pulmonary valve syndrome and the Nuss procedure for pectus excavatum in a 3-year-old child.