The Impact of Dominant Ventricular Morphology on the Early Postoperative Course After the Glenn Procedure.

The dominant ventricular morphology affects both the early and late outcomes of the Fontan procedure, but its impact on the patients' status immediately following the Glenn procedure is unknown. This study aims to evaluate the effect of the infants' dominant ventricular morphology on the immediate course after undergoing the Glenn procedure. This single-center, retrospective study included all patients who underwent the Glenn procedure between October 2003 and May 2016. The patients were divided into two groups according to their dominant ventricular morphology. Their postoperative records were reviewed and compared. Out of the 89 patients who underwent the Glenn procedure during the study period, 40 (44.9%) had dominant right ventricular morphology and 49 (55.1%) had left ventricular morphology. There were no significant group differences in baseline characteristics or operative data. The maximal postoperative vasoactive-inotropic score was significantly higher and the extent of ventricular dysfunction was significantly more severe in the dominant right ventricle group (P < 0.05). The length of hospitalization was slightly but not significantly longer in the hypoplastic LV group. It is concluded that patients with a dominant LV morphology had a superior ventricular function and required less inotropic support compared to that of a dominant RV morphology in the immediate postoperative course following the Glenn procedure. Survival was not affected by these differences. Further study to determine the pathophysiologic basis for these differences is warranted.

Normothermic Versus Hypothermic Norwood Procedure.

BACKGROUND: Either deep hypothermia with circulatory arrest or hypothermic perfusion with antegrade selective cerebral perfusion is used during the Norwood procedure for hypoplastic left heart syndrome. Normothermic perfusion has been described for pediatric patients. The aim of this study was to compare the early outcomes of patients undergoing the Norwood procedure with antegrade selective cerebral perfusion under hypothermia with the procedure under normothermia. METHODS: From 2005 to 2020, 117 consecutive patients with hypoplastic left heart syndrome underwent the Norwood procedure: 68 (58.2%) under hypothermia and 49 (41.8%) under normothermia. Antegrade selective cerebral perfusion flow was adjusted to maintain right radial arterial pressure above 50 mm Hg, and a flow rate of 40 to 50 mL kg-1 min-1. Baseline characteristics, operative data, and postoperative outcomes including lactate recovery time were compared. RESULTS: The baseline characteristics and cardiovascular diagnosis were similar in both groups. The normothermic group had a significantly shorter bypass time (in minutes) of 90.31 (±31.60) versus 123.63 (±25.33), a cross-clamp time of 45.24 (±16.35) versus 81.93 (±16.34), and an antegrade selective cerebral perfusion time of 25.61 (±13.84) versus 47.30 (±14.35) (P < .001). There were no statistically significant differences in the immediate postoperative course, or in terms of in-hospital mortality, which totaled 9 (18.4%) in the normothermic group, and 10 (14.9%) in the hypothermic group (P = .81). CONCLUSION: The normothermic Norwood procedure with selective cerebral perfusion is feasible and safe in terms of in-hospital mortality and short-term outcomes. It is comparable to the standard hypothermic Norwood with selective cerebral perfusion.

Novel cfDNA Methylation Biomarkers Reveal Delayed Cardiac Cell Death after Open-heart Surgery.

The use of cardiopulmonary bypass (CPB) is thought to cause delayed cardiac damage. DNA methylation-based liquid biopsies are novel biomarkers for monitoring acute cardiac cell death. We assessed cell-free DNA molecules as markers for cardiac damage after open-heart surgery. Novel cardiomyocyte-specific DNA methylation markers were applied to measure cardiac cfDNA in the plasma of 42 infants who underwent open-heart surgery. Cardiac cfDNA was elevated following surgery, reflecting direct surgery-related tissue damage, and declined thereafter in most patients. The concentration of cardiac cfDNA post-surgery correlated with the duration of CPB and aortic cross clamping. Strikingly, cardiac cfDNA at 6 h predicted duration of mechanical ventilation and maximal vasoactive-inotropic score better than did maximal troponin levels. Cardiac cfDNA reveals heart damage associated with CPB, and can be used to monitor cardiac cell death, to predict clinical outcome of surgery and to assess performance of cardioprotective interventions.

Dominant Ventricular Morphology and Early Postoperative Course After the Fontan Procedure.

BACKGROUND: Single ventricle heart disease comprises a wide variety of critical heart defects that lead to the provision of systemic cardiac output by one dominant ventricle. It requires staged surgical palliation that culminates in Fontan circulation. Dominant ventricular morphology in single ventricle patients reportedly has an impact on postoperative morbidity and mortality with varying results. The objectives of this study were to examine the association between ventricular morphology and the early postoperative course after the Fontan procedure. METHODS: A retrospective cohort study in a tertiary referral pediatric medical center that included 98 consecutive patients who underwent Fontan procedure between October 2009 and May 2016. Postoperative outcomes were compared between patients with left ventricular morphology and those with right ventricular morphology (crude effect and regression analysis). RESULTS: Patients with right ventricular morphology had longer postoperative hospitalizations compared to patients with left ventricular morphology (26.5 days vs 18.2 days, respectively, P = .028), higher postoperative maximal vasoactive-inotropic scores (25.6 vs 12.4, P = .02), higher serum lactate levels (7.7 mmol/L vs 6.4 mmol/L, P = .03), higher proportions of ventilation throughout 24 h or more (16 patients [38%] vs 8 patients [14%], P = .009), higher proportions of ventricular dysfunction (12 patients [29%] vs 5 patients [9%], P = .0001), and lower blood oxygen saturation levels at discharge (87% vs 92%, P = .03). CONCLUSIONS: The Fontan procedure in patients with right ventricular morphology is associated with longer postoperative hospitalization and worse early postoperative characteristics (ventricular dysfunction and atrioventricular valve regurgitation) as well as higher rates of early, transient signs of sub-optimal postoperative hemodynamics compared to those with left ventricular morphology.

Transfusion-related acute hepatic injury following postoperative platelets administration in pediatric patients undergoing the Fontan procedure.

OBJECTIVE: The final common pathway of single ventricle patients is the Fontan procedure. Among the immediate postoperative complications is acute hepatic injury presented by marked elevation of liver enzymes (alanine transaminase [ALT] and aspartate transaminase [AST]). We aimed to determine the contribution of blood products transfusion to acute hepatic injury. DESIGN: Single center retrospective cohort study. SETTING: Pediatric Cardiac Intensive Care Unit at a tertiary medical center. PATIENTS: Ninety-nine pediatric patients undergoing the Fontan procedure between January 2009 and December 2016. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Out of the four types of blood products, transfusion of platelets was found to significantly affect postoperative levels of ALT and AST. Additional factors included postoperative administration of sodium bicarbonate, decreased flow through the Fontan canal and decreased urine output. Preoperative pulmonary artery pressure and pulmonary vascular resistance, cardiopulmonary bypass time, aortic cross-clamp time, amount of postoperative bleeding, and vasoactive-inotropic score did not influence liver enzymes levels CONCLUSIONS: In pediatric Fontan patients, platelets transfusions contribute to an acute hepatic injury. The relation between platelets and transfusion-related acute lung injury (TRALI) has been well described, but this is the first time it is being described in regard to acute hepatic injury (TRAHI). Changing platelet transfusion strategy could decrease morbidity in Fontan patients but further research is needed.

The Bilateral Bidirectional Glenn Operation as a Risk Factor Prior to Fontan Completion in Complex Congenital Heart Disease Patients.

INTRODUCTION: The Glenn procedure is generally performed as a second-stage palliative procedure toward the completion of Fontan circulation in patients with a functionally univentricular heart. Safe Fontan completion requires normal ventricular function, competent atrioventricular valves, normal pulmonary arteries anatomy, and low pulmonary vascular resistances (PVRs), which is merely an estimation that considers both lungs as a single unit. Clinical observations revealed that patients who previously underwent bilateral bidirectional cavopulmonary anastomosis (b-BCPA) had a stormier postoperative course in respect to other patients with previous unilateral BCPA (u-BCPA) postoperatively after Fontan completion. This retrospective study was designed to compare and analyze the outcomes of patients following Fontan completion with previous u-BCPA versus b-BCPA. PATIENTS AND METHODS: A total of 98 patients were divided into two groups based on the presence or absence of bilateral superior vena cava (SVC). Group 1 included 80 patients with unilateral SVC, and group 2 included 18 patients with bilateral SVC. Univariate and multivariate (SPSS) analyses were performed with regard to mortality and failure. P value of <.05 was considered as significant. RESULTS: Prior to the total cavopulmonary anastomosis operation, the G1 and G2 had similar demographic and physiological findings, ages and weights were 4.3 ± 1.72 years and 15.0 ± 3.71 kg in G1 and 4.8 ± 3.21 years and 17.5 ± 9.76 kg in G2. Mean end-diastolic ventricular pressures (in mm Hg) were 10.50 ± 2.86 in G1 and 10.28 ± 3.07 in G2 and the mean PVRs (in Woods units) were 1.66 ± 1.29 in G1 and 1.49 ± 0.82 in G2. The Stormy postoperative course, Fontan failure, and early mortality were all significantly higher in G2 in respect to G1 ( P value <.05). G1 mortality rate was 3.7%, 3 patients of 80, while in G2, the mortality rate was 22%, 4 patients of 18. Late Fontan failure rates were 6% for G1 patients where two patients developed pulmonary hypertension, two patients developed heart failure, and one patient had protein losing enteropathy (PLE), and 22% for the G2 patients of which two patients developed heart failure, one patient had PLE, and one patient had persistent low systemic venous saturation. CONCLUSIONS: Our results have demonstrated that patients after b-BCPA might have a tendency for worse outcomes upon Fontan completion. The b-BCPA is associated with pulmonary artery bifurcation stenosis and presents multiple sources of pulmonary blood flow where conventional PVR calculation might be imprecise and misleading since it considers the lungs as a single unit. Therefore, b-BCPA engenders correction of the conventional PVR calculation to consider each lung separately. Furthermore, the surgical approach for patients with persistent left SVC and univentricular heart should be modified.

Pediatric Cardiac Surgery and Pain Management: After 40 Years in the Desert, Have We Reached the Promised Land?

Pain prevention in the pediatric population is mandatory and an integrative aspect of medical practice. Optimal pain management is the right of all patients and the responsibility of all health professionals. The key to adequate pain management is assessing its presence and severity, identifying those who require intervention, and appreciating treatment efficacy. The population of pediatric patients undergoing cardiac surgery is unique in both clinical severity and hemodynamic response to painful stimuli, thus making pain management even more challenging. In this review, we will describe the different pain assessment tools as well as intra- and postoperative regimens of pain management.

Estrogen-mediated downregulation of AIRE influences sexual dimorphism in autoimmune diseases.

Autoimmune diseases affect 5% to 8% of the population, and females are more susceptible to these diseases than males. Here, we analyzed human thymic transcriptome and revealed sex-associated differences in the expression of tissue-specific antigens that are controlled by the autoimmune regulator (AIRE), a key factor in central tolerance. We hypothesized that the level of AIRE is linked to sexual dimorphism susceptibility to autoimmune diseases. In human and mouse thymus, females expressed less AIRE (mRNA and protein) than males after puberty. These results were confirmed in purified murine thymic epithelial cells (TECs). We also demonstrated that AIRE expression is related to sexual hormones, as male castration decreased AIRE thymic expression and estrogen receptor α-deficient mice did not show a sex disparity for AIRE expression. Moreover, estrogen treatment resulted in downregulation of AIRE expression in cultured human TECs, human thymic tissue grafted to immunodeficient mice, and murine fetal thymus organ cultures. AIRE levels in human thymus grafted in immunodeficient mice depended upon the sex of the recipient. Estrogen also upregulated the number of methylated CpG sites in the AIRE promoter. Together, our results indicate that in females, estrogen induces epigenetic changes in the AIRE gene, leading to reduced AIRE expression under a threshold that increases female susceptibility to autoimmune diseases.

Central role of interferon-beta in thymic events leading to myasthenia gravis.

The thymus plays a primary role in early-onset Myasthenia Gravis (MG) mediated by anti-acetylcholine receptor (AChR) antibodies. As we recently showed an inflammatory and anti-viral signature in MG thymuses, we investigated in detail the contribution of interferon (IFN)-I and IFN-III subtypes in thymic changes associated with MG. We showed that IFN-I and IFN-III subtypes, but especially IFN-ß, induced specifically α-AChR expression in thymic epithelial cells (TECs). We also demonstrated that IFN-ß increased TEC death and the uptake of TEC proteins by dendritic cells. In parallel, we showed that IFN-ß increased the expression of the chemokines CXCL13 and CCL21 by TECs and lymphatic endothelial cells, respectively. These two chemokines are involved in germinal center (GC) development and overexpressed in MG thymus with follicular hyperplasia. We also demonstrated that the B-cell activating factor (BAFF), which favors autoreactive B-cells, was overexpressed by TECs in MG thymus and was also induced by IFN-ß in TEC cultures. Some of IFN-ß effects were down-regulated when cell cultures were treated with glucocorticoids, a treatment widely used in MG patients that decreases the number of thymic GCs. Similar changes were observed in vivo. The injections of Poly(I:C) to C57BL/6 mice triggered a thymic overexpression of IFN-ß and IFN-α2 associated with increased expressions of CXCL13, CCL21, BAFF, and favored the recruitment of B cells. These changes were not observed in the thymus of IFN-I receptor KO mice injected with Poly(I:C), even if IFN-ß and IFN-α2 were overexpressed. Altogether, these results demonstrate that IFN-ß could play a central role in thymic events leading to MG by triggering the overexpression of α-AChR probably leading to thymic DC autosensitization, the abnormal recruitment of peripheral cells and GC formation.

Hemodynamics and arteriovenous malformations in cavopulmonary anastomosis: the case for residual antegrade pulsatile flow.

OBJECTIVES: Continuous flow in Fontan circulation results in impairment of pulmonary artery endothelial function, increased pulmonary vascular resistance, and, potentially, late failure of Fontan circulation. Bidirectional cavopulmonary shunt is the interim procedure in palliation of patients with single-ventricle physiology, but pulmonary arteriovenous malformations occur in many patients. In a porcine chronic model of cavopulmonary shunt, we studied pulmonary hemodynamics, pulmonary arteriovenous malformation occurrence, and gas exchange capabilities. We hypothesized that residual antegrade pulsatile pulmonary flow may attenuate the deleterious effects of nonpulsatile Fontan-type circulation. METHODS: Thirty pigs underwent a sham procedure (n = 10, group I), a cavopulmonary shunt with right pulmonary artery ligation (n = 10, group II, nonpulsatile), or a cavopulmonary shunt with proximal right pulmonary artery partial ligation (n = 10, group III, micropulsatile). Three months later, in vivo hemodynamics, blood gas exchange, pulmonary arteriovenous malformation occurrence, and lung histology were assessed. RESULTS: At 3 months, group II right lungs demonstrated significantly increased pulmonary artery pressure, pulmonary vascular resistance, and evidence of pulmonary arteriovenous malformations compared with groups I and III (all P < .001). Group III lungs also showed increased pulmonary artery pressure and pulmonary vascular resistance compared with the sham group, but significantly less than group II. Group III right lungs had the best gas exchange performance, with less histologic changes compared with group II. CONCLUSIONS: We developed a viable chronic large animal model of bidirectional cavopulmonary anastomosis. Residual antegrade pulsatile flow in the setting of a cavopulmonary shunt prevents pulmonary arteriovenous malformation formation and attenuates, but does not suppress, the development of pulmonary hypertension. From a clinical standpoint, these data would support keeping a small amount of antegrade pulsatile flow during creation of a cavopulmonary shunt.

Effects of lack of pulsatility on pulmonary endothelial function in the Fontan circulation.

OBJECTIVES: Continuous flow in the Fontan circulation results in impairment of pulmonary artery endothelial function, increased pulmonary arterial resistance, and, potentially, late failure of Fontan circulation. We investigated the mechanisms of vascular remodeling and altered vascular reactivity associated with chronic privation of pulsatility on pulmonary vasculature. METHODS: A total of 30 pigs were evenly distributed in 3 groups: 10 underwent a sham procedure (group I) and 20 underwent a cavopulmonary shunt between the superior vena cava and right pulmonary artery--10 with complete ligation of the proximal right pulmonary artery (group II, nonpulsatile) and 10 with partial ligation (group III, micropulsatile). At 3 months postoperatively, the in vivo hemodynamics, in vitro vasomotricity (concentration response curves on pulmonary artery isolated rings), and endothelial nitric oxide synthase protein level were assessed. A comparison between group and between the right and left lung in each group was performed. RESULTS: Group II developed right pulmonary hypertension and increased right pulmonary resistance. Endothelial function was altered in group II, as reflected by a decrease in the vasodilation response to acetylcholine and ionophoric calcium but preservation of the nonendothelial-dependent response to sodium nitroprusside. Group III micropulsatility attenuated pulmonary hypertension but did not prevent impairment of the endothelial-dependant relaxation response. Right lung Western blotting revealed decreased endothelial nitric oxide synthase in group II (0.941 ± 0.149 vs sham 1.536 ± 0.222, P = .045) that was preserved in group III (1.275 ± 0.236, P = .39). CONCLUSIONS: In a chronic model of unilateral cavopulmonary shunt, pulsatility loss resulted in an altered endothelial-dependant vasorelaxation response of the pulmonary arteries. Micropulsatility limited the effects of pulsatility loss. These results are of importance for potential therapies against pulmonary hypertension in the nonpulsatile Fontan circulation, by retaining accessory pulmonary flow or pharmaceutical modulation of nonendothelial-dependant pulmonary vasorelaxation.

Potts shunt in children with idiopathic pulmonary arterial hypertension: long-term results.

BACKGROUND: Idiopathic pulmonary arterial hypertension (IPAH) remains a progressive fatal disease. Palliative Potts shunt has been proposed in children displaying suprasystemic IPAH. METHODS: A retrospective multicenter study was performed to evaluate Potts shunt in pediatric IPAH. RESULTS: Between 2003 and 2010, 8 children with suprasystemic IPAH and in World Health Organization functional class IV despite medical pulmonary arterial hypertension therapy underwent Potts shunt. Age at IPAH diagnosis ranged from 4 to 180 months (median age, 64 months). Surgical procedure was performed in a mean delay of 41.9±54.3 months (range, 4 to 167 months; median delay, 20 months) after IPAH diagnosis. Mean size of the Potts shunt was 9.25±3.30 mm. Two patients, whose medical pulmonary arterial hypertension therapy had been interrupted just after surgery, died at postoperative days 11 and 13 of acute pulmonary hypertensive crisis. After a mean follow-up of 63.7±16.1 months, the 6 children who were discharged from the hospital were alive. Functional status improved markedly in the 6 survivors, with a World Health Organization functional class I (n=4) or II (n=2) at last follow-up, consistent with significant improvement of 6-minute-walk distance (302±95 m [51%±20% of theoretical values] versus 456±91 m [68%±10% of theoretical values]; p=0.038) and decrease of brain natriuretic peptide levels (608±109 pg/mL versus 76±45 pg/mL; p=0.035). No Potts shunt was found to be restrictive at last echocardiography. CONCLUSIONS: Palliative Potts shunt constitutes a new alternative to lung transplantation in severely ill children with suprasystemic IPAH, carrying a prolonged survival and persistent improvement in functional capacities.

Tetralogy of Fallot with an abnormal coronary artery: surgical options and prognostic factors.

OBJECTIVES: The objectives were to determine in patients with Tetralogy of Fallot (ToF) and abnormal coronary artery (ACA): the long-term outcomes of different surgical strategies; the risk factors for right ventricular outflow tract (RVOT) obstruction, reoperation, heart failure and mortality. To date, the surgical strategies and prognostic factors for repair of ToF with an ACA, crossing the RVOT and avoiding a classic repair, have not been evaluated in a large series using a multivariate analysis. METHODS: A retrospective study (1986-2011) included 72 patients. The mean follow-up was 9.6 ± 6.8 years. Median age at surgery was 1.5 years (0.2-11.3). The main surgical techniques were 'tailored' right ventriculotomy and patch of the RVOT (63%; n = 45), implantation of a conduit between the right ventricle (RV) and the pulmonary artery (PA; 25%; n = 18) and a transatrial ± transpulmonary approach (11%; n = 8). Univariate and multivariate logistic regression analyses were performed. RESULTS: Intrahospital mortality was 2.7%. Actuarial freedom from reoperation and actuarial survival at 15 years were 77% (confidence interval [CI]: 70-83%) and 94% (CI: 90-97%), respectively. Reoperations occurred more frequently after conduit implantation (50%) than after patch reconstruction (17%) or transatrial ± transpulmonary approach (0%; P = 0.002). The transatrial ± transpulmonary approach was significantly less complicated, with a long-term RVOT obstruction of 0% compared with the other surgical techniques (45.4%; P = 0.03). Implantation of a RV-PA conduit was an independent risk factor for RVOT obstruction (odds ratio [OR]: 31; P < 0.001) and reoperation (OR: 20; P = 0.02). An immediate postoperative right ventricle/left ventricle (RV/LV) pressure ratio >0.5 was independently associated with a long-term RV/LV pressure ratio >0.5 (OR: 14; P = 0.001), but was not a risk factor for reoperation (P = 0.8). Postoperative electric ischaemic signs independently increased the risk of long-term heart failure (OR: 22; P = 0.04). CONCLUSIONS: The transatrial ± transpulmonary approach displays the best long-term outcomes, by reducing the risks for RVOT obstruction and reoperation, but does not improve the patient survival. A RV-PA conduit was an independent risk factor for RVOT obstruction and reoperation. An immediate postoperative RV/LV pressure ratio >0.5 was not a risk factor for reoperation. The transatrial ± transpulmonary approach should be preferred to the implantation of a conduit or a tailored right ventriculotomy whenever possible.

Electrical velocimetry as a tool for measuring cardiac output in small infants after heart surgery.

PURPOSE: Cardiac output (CO), the product of stroke volume (SV) and heart rate, is essential to guarantee organ perfusion, especially in the intensive care setting. As invasive measurement of CO bears the risk of complications there is a need for non-invasive alternatives. We investigated if electrical velocimetry (EV) and transthoracic Doppler (Doppler-TTE) are interchangeable for the non-invasive measurement of SV and able to reflect the post-surgical SV/CO trend. METHODS: Comparison of SV measurements by EV and Doppler-TTE was performed in 24 newborns after switch operation (n = 240 measurements). Three subgroups of measurements (=periods) were created according to the patients' status in the course of post-surgical CO recovery. RESULTS: Bland-Altman analysis found acceptable bias and limits of agreement for the interchangeability of the two methods. Mean overall SV was 3.7 ml with a mean overall bias of 0.28 ml (=7.6 %). The mean percentage error of 29 % was acceptable according to the method of Critchley and Critchley. Overall precision expressed by the coefficient of variation (CV) was 6.6 % for SV(TTE) and 4.4 % for SV(EV). SV(TTE) and SV(EV) medians in the three periods were significantly different and documented the post-surgical CO trend. CONCLUSIONS: EV and Doppler-TTE are interchangeable for estimating SV. EV has the advantages of easy handling and allows continuous measurement.

Continuous cerebral perfusion for aortic arch repair: hypothermia versus normothermia.

BACKGROUND: Deep hypothermia with circulatory arrest (CA) is routinely used for aortic arch repair. Antegrade selective cerebral perfusion (ASCP) has been proposed to avoid neurologic complications. The optimal temperature during aortic arch repair with ASCP is not well established. We therefore compared early outcomes of patients undergoing aortic arch repair associated with intracardiac repair with ASCP either with hypothermia (<28°C, group I; n=70) or normothermia (>34°C, group II; n=40). METHODS: From 2002 to 2008, 110 consecutive patients with interrupted aortic arch (n=40) or coarctation of the aorta (n=70) and cardiac anomalies underwent intracardiac and aortic arch repair without CA. Median age at repair was 12 days. Full cardiopulmonary bypass (CPB), high hematocrit, and high rates of flow were used. ASCP flow was adjusted to maintain arterial pressure at greater than or equal to 50 mm Hg. ASCP was achieved either through a Gore-Tex (W. L. Gore & Associates, Inc., Elkton, MD) graft to the innominate artery (n=36) or by direct cannulation (n=74). An electroencephalogram (EEG) was continuously monitored and 30 patients were monitored by near-infrared spectroscopy (NIRS). RESULTS: Preoperative data were similar in both groups. Group II demonstrated higher ASCP flows (p<0.001). Time to extubation, stay in the intensive care unit (ICU), and postoperative urine output and lactate levels were similar between groups. Mortality was 8.5% in group I versus 10% in group II. During the postoperative course, there were no clinical or electrical neurologic events in either group. CONCLUSIONS: Antegrade selective cerebral perfusion can safely avoid CA. No worse, early, or long-term effects of ASCP with normothermia were found.

Surgical palliation of primary pulmonary arterial hypertension by a unidirectional valved Potts anastomosis in an animal model.

OBJECTIVE: Patients with idiopathic pulmonary hypertension are at risk for right-sided heart failure and sudden death. Despite improvement in pharmacologic management, some still require lung transplantation. Potts anastomosis has been demonstrated as a good palliation in children to alleviate symptoms and medical therapy despite desaturation in the lower part of the body. Young adult patients with pulmonary hypertension and isosystemic pressure remain at risk, particularly at exercise. The goal of this research was to find a palliation for patients in whom suprasystemic pulmonary hypertension developed at exercise. Creating a Potts anastomosis involved a unidirectional valve between the left pulmonary artery and the descending aorta. METHODS: Experimental study was performed on 14 pigs. A prosthetic patch of polytetrafluoroethylene (Gore-Tex; WL Gore & Associates Inc, Newark, Del) was used to create the unidirectional valve and implanted in the Potts anastomosis. Via a left thoracotomy, an aorto-aortic shunt between the aortic isthmus and the distal descending thoracic aorta was instituted, allowing a safe surgical procedure. Intrapulmonary injection of Erciplex glue (Peters Surgical, Bobigny, France), diluted in 70% alcohol, was used to create acute pulmonary hypertension. The right to left shunt across the unidirectional valvular patch was evaluated after clamping the aorta in the acute phase of pulmonary hypertension by echo-pulsed Doppler at the level of the descending thoracic aorta by withdrawal of blood gas (arterial carbon dioxide tension, alveolar carbon dioxide tension) and assessment of peripheral oxygen saturation. Similar reevaluation of the shunt was performed at a mean interval of 13 ± 2.5 weeks. RESULTS: In the first series, Erciplex glue increased pulmonary artery pressure from 15.3 ± 3.1 mm Hg to 38.7 ± 6.0 mm Hg. Mean peripheral oxygen saturation decreased from 100% to 85% ± 1.5%. Mean partial pressure of carbon dioxide increased from 31.9 ± 9.1 mm Hg to 46.2 ± 12.5 mm Hg after shunt opening (P < .01), and mean peripheral oxygen decreased from 435.1 ± 109.4 mm Hg to 261.9 ± 77.9 mm Hg (P < 0.05), indicating right to left shunt through the Potts valve (P < .013). Pulsed Doppler showed a mean peak laminar flow of 133.3 ± 35.3 cm/s before aortic clamping, turbulent flow of 234.9 ± 40.1 cm/s after glue injection, and return of laminar flow 128.5 ± 30.1 cm/s after aortic isthmus unclamping. In the second series, the same results were obtained but with a lesser peak flow velocity because of the endothelialization on the valvular patch. Gross analysis of the patch did not show thrombosis, aneurysm, or fissure. CONCLUSIONS: Palliation of exercise suprasystemic pulmonary hypertension was demonstrated by a unidirectional valved Potts anastomosis. This technique can be of help in young adult patients with pulmonary hypertension and isosystemic pressure but with exercise intolerance.

Very early correction of anomalous left coronary artery from the pulmonary artery improves intensive care management.

BACKGROUND: Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) can sometimes be diagnosed very early in newborns and thus be corrected surgically before any myocardial ischaemia occurs. AIM: To evaluate the influence of this very early surgery on intensive care management and long-term outcome. METHODS: All children operated on for ALCAPA before the age of 1 year between 1995 and 2010 were considered. Those operated on before the onset of ischaemia (group B) were compared with a matched group of children of similar weight who were operated on by the same surgeon on a close surgery date (group A). RESULTS: We obtained a homogenous population of 13 children (eight in group A; five in group B) with no significant weight difference between groups. The surgical technique and peroperative variables were similar in both groups. There was one death in each group. The group B death was due to postoperative occurrence of global myocardial infarction despite correct surgical reparation. Mechanical ventilation duration, inotropic support duration, intensive care duration and long-term complications were lower in group B. CONCLUSION: Very early ALCAPA surgical correction before occurrence of ischaemia must be encouraged whenever possible because it simplifies intensive care management and prevents persistent mitral regurgitation, but it does not reduce peroperative risk.

Anomalous origin of the left coronary artery from the pulmonary artery associated with severe left ventricular dysfunction: results in normothermia.

BACKGROUND: Repair of anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) carries a high risk of operation, particularly in those with poor left ventricular function. In this study, we assessed the outcomes of patients who presented with severe preoperative left ventricular dysfunction (shortening fraction <15%) who underwent the repair under normothermic bypass. METHODS: Since September 2002, 21 infants with severe left ventricular dysfunction underwent surgical repair using a direct coronary reimplantation technique. Mean age of patients was 5.3 +/- 3.8 months. Moderate or severe mitral regurgitation present in 5 patients was not addressed at the operation. Repair was performed under normothermic cardiopulmonary bypass and myocardial protection was achieved by intermittent antegrade normothermic blood cardioplegia. RESULTS: Mean cardiopulmonary bypass and cross-clamp times were 153.5 +/- 51 and 50 +/- 14.5 minutes, respectively. There was one (4.7%) early death because of sudden cardiac arrest 48 hours after successful weaning from mechanical ventilation. One patient required urgent left coronary artery stenting on the 34th postoperative day because of early reimplantation failure. There was no late death. Echocardiographic evaluation revealed a significant improvement in terms of shortening fraction (preoperative, 10.3 +/- 3.2% vs follow-up, 33 +/- 7.7%, p < 0.0001). CONCLUSIONS: Our results suggest that the repair of anomalous origin of the left coronary artery from the pulmonary artery can be accomplished with acceptable mortality and morbidity rates even in patients having severely depressed left ventricular function. Normothermic cardiopulmonary bypass is safe and effective in children who have a limited tolerance to further ischemic insult.