Prospective Randomized Pilot Trial on the Effects of Mild Hypercapnia on Cerebral Oxygen Saturation in Patients Undergoing Off-Pump Coronary Artery Bypass Grafting.

OBJECTIVE AND DESIGN: A single-center prospective randomized controlled study was conducted to assess the effect of targeted mild hypercapnia (TMH) on cerebral oxygen saturation (rSO2) in patients undergoing off-pump coronary artery bypass grafting (CABG). SETTING AND PARTICIPANTS: A prospective randomized controlled study involving 100 patients undergoing off-pump CABG at U. N. Mehta Hospital, Ahmedabad, Gujarat, India. INTERVENTION: Patients were randomized to either the TMH (PaCO2 45-55 mmHg) or the targeted normocapnia (TN; PaCO2 35-45 mmHg) group, containing 50 patients in each group. MEASUREMENTS: Monitoring of rSO2, heart rate, mean arterial pressure (MAP), PaCO2, and peripheral oxygen saturation was done at baseline, after induction, after left internal mammary artery harvesting, at each grafting (distal and proximal), after protamine, and after shifting to the intensive care unit. The standardized minimental-state examination (SMMSE) was performed preoperatively and at 8, 12, and 24 hours postextubation. Data were analyzed using an independent sample t test. RESULTS: The TMH group had higher MAP during grafting (p < 0.001) and higher rSO2 on both sides during distal and proximal grafting (p < 0.001) and after protamine (p < 0.05), as compared to the TN group. Compared to preoperative values, SMMSE scores in the TN group were significantly lower at 12 and 24 hours postextubation (p < 0.001). CONCLUSION: TMH during grafting increased the cerebral blood flow and rSO2 when hemodynamic instability was very common. It has a protective role on the brain and helps maintain cognition postoperatively.

Surgical outcomes of double-orifice mitral valve repair in patients with atrioventricular canal defects: a systematic review and meta-analysis.

INTRODUCTION: Double-orifice mitral valve or left atrioventricular valve is a rare congenital cardiac anomaly that may be associated with an atrioventricular septal defect. The surgical management of double-orifice mitral valve/double-orifice left atrioventricular valve with atrioventricular septal defect is highly challenging with acceptable clinical outcomes. This meta-analysis is aimed to evaluate the surgical outcomes of double-orifice mitral valve/double-orifice left atrioventricular valve repair in patients with atrioventricular septal defect. METHODS AND RESULTS: A total of eight studies were retrieved from the literature by searching through PubMed, Google Scholar, Embase, and Cochrane databases. Using Bayesian hierarchical models, we estimated the pooled proportion of incidence of double-orifice mitral valve/double-orifice left atrioventricular valve with atrioventricular septal defect as 4.88% in patients who underwent surgical repair (7 studies; 3295 patients; 95% credible interval [CI] 4.2-5.7%). As compared to pre-operative regurgitation, the pooled proportions of post-operative regurgitation were significantly low in patients with moderate status: 5.1 versus 26.39% and severe status: 5.7 versus 29.38% [8 studies; 171 patients]. Moreover, the heterogeneity test revealed consistency in the data (p < 0.05). Lastly, the pooled estimated proportions of early and late mortality following surgical interventions were low, that is, 5 and 7.4%, respectively. CONCLUSION: The surgical management of moderate to severe regurgitation showed corrective benefits post-operatively and was associated with low incidence of early mortality and re-operation.

Ductus arteriosus morphology in duct-dependent pulmonary circulation: CT classification and pattern in different ventricular morphology.

BACKGROUND: The objective was to study the ductus arteriosus morphology in duct-dependent pulmonary circulation and its pattern in different ventricle morphology using CT angiography. METHOD: From January 2013 to December 2015, patients aged 6 months and below with duct-dependent pulmonary circulation underwent CT angiography to delineate the ductus arteriosus origin, tortuosity, site of insertion, and pulmonary artery anatomy. The ductus arteriosus were classified into type I, IIa, IIb, and III based on its site of origin, either from descending aorta, distal arch, proximal arch, or subclavian artery, respectively. RESULTS: A total of 114 patients and 116 ductus arteriosus (two had bilateral ductus arteriosus) were analysed. Type I, IIa, IIb, and III ductus arteriosus were seen in 13 (11.2 %), 71 (61.2%), 21 (18.1%), and 11 (9.5%), respectively. Tortuous ductus arteriosus was found in 38 (32.7%), which was commonly seen in single ventricular lesions. Ipsilateral and bilateral branch pulmonary artery stenosis was seen in 68 (59.6%) and 6 (5.3%) patients, respectively. The majority of patients with pulmonary atresia intact ventricular septum had type I (54.4%) and non-tortuous ductus arteriosus, while those with single and biventricular lesions had type II ductus arteriosus (84.9% and 89.7%, respectively). Type III ductus arteriosus was more common in biventricular lesions (77.8%). CONCLUSIONS: Ductus arteriosus in duct-dependent pulmonary circulation has a diverse morphology with a distinct origin and tortuosity pattern in different types of ventricular morphology. CT may serve as an important tool in case selection and pre-procedural planning for ductal stenting.

Comparison between Del Nido and conventional blood cardioplegia in pediatric open-heart surgery.

BACKGROUND: Del Nido cardioplegia (DNc) was designed for superior myocardial protection during cardiopulmonary bypass (CPB). We conducted a retrospective review to explore if DNc was associated with increase in systemic ventricle dysfunction (sVD) following pediatric CPB. METHODS AND RESULTS: This single-center, retrospective study included 1534 patients undergoing CPB between 2013 and 2016, 997 prior to center-wide conversion to DNc and 537 following. The primary outcome was new postoperative ≥moderate sVD by echocardiogram. Secondary outcomes included sVD of any severity and right ventricular dysfunction. Data was evaluated by interrupted time-series analysis. Groups had similar cardiac diagnoses and surgical complexity. Del Nido cardioplegia was associated with longer median (IQR) CPB [117 (84-158) vs 108 (81-154), p = 0.04], and aortic cross-clamp [83 (55-119) vs 76 (53-106), p = 0.03], and fewer cardioplegia doses [2 (1-2) vs 3 (2-4), p < 0.0001]. Mortality was similar in both groups. Frequency of sVD was unchanged following DNc, including predetermine subgroups (neonates, infants, and prolonged cross-clamp). Logistic regression showed a significant rise in right ventricular dysfunction (OR 5.886 [95% CI: 0.588, 11.185], p = 0.03) but similar slope. CONCLUSIONS: Use of DNc was not associated with increased in reported sVD, and provided similar myocardical protection to the systemic ventricle compared to conventional cardioplegia but may possibly impact right ventricular function. Studies evaluating quantitative systolic and diastolic function are needed.

Mechanical Circulatory Support for Patients With Adult Congenital Heart Disease.

Advances in surgical and medical care of children born with heart defects have led to the emergence of a unique subgroup of young adults known as adults with congenital heart disease (ACHD). Heart failure (HF) is the leading cause of mortality and morbidity in this subset. Management of HF is challenging in these patients owing to inherent structural variations with their associated physiological consequences. Heart transplantation is of limited utility in this group either because of donor shortage or associated comorbidities that make these patients ineligible for transplantation. Mechanical circulatory support (MCS) devices have evolved as an alternative treatment modality in supporting the failing myocardium of this population, but are often used less frequently than in those with a structurally normal heart because of the unique anatomical and physiological variations. These variations create a need to gather adequate knowledge on how best to support the hearts of ACHD patients in order to reduce mortality and morbidity. This review presents clinical experience with MCS in ACHD patients.

Abnormal fetal cerebral and vascular development in hypoplastic left heart syndrome.

OBJECTIVE: To assess the cerebral and vascular development in fetuses with hypoplastic left heart syndrome (HLHS). METHODS: Pregnant women carrying fetuses diagnosed with HLHS who decided to interrupt their pregnancies were included in our study. Aortic size and blood flow were assessed based from fetal echocardiography. Immunohistochemical staining was performed in brain sections obtained from pathology in fetuses with HLHS and control fetuses without heart disease. RESULTS: Twenty-seven midgestation fetal HLHS were included (gestational age, 23.3 ± 3.4 weeks). Head circumference z scores were lower in HLHS fetuses. Middle cerebral artery pulsatility index, a measure of cerebrovascular resistance, was inversely correlated with the ascending aortic z score (P < 0.05). Fetuses with HLHS had lower capillary density in the germinal matrix and their capillaries were larger compared with control fetuses with (P < 0.05). The expression of neuronal differentiation marker, FGFR1, and oligodendrocyte precursor, O4, were lower in HLHS brains compared with controls (P < 0.05). CONCLUSION: Our study identified abnormalities of vascular flow and structural brain abnormalities in fetal HLHS associated with impaired neuronal and oligodendrocyte differentiation, as well as cerebral growth impairment, early in gestation. These findings may be related in part to early vascular abnormalities.

Tetralogy of Fallot with acquired coronary artery disease-An unusual presentation.

Coronary artery disease developing in tetralogy of Fallot (TOF) is rare. We report a rare case of TOF with acquired coronary artery disease, treated simultaneously with intra cardiac repair and multi vessel coronary artery bypass grafting.

Aortic valve repair in the pediatric population: emerging role of aortic valve neocuspidization (AVNeo procedure).

Management of aortic valve diseases in children is challenging owing to the quality and quantity of the native tissue for repair, limitations in the currently available biological materials to supplement the repair and to achieve a long-lasting durable repair in an annulus where there is still growth potential. The aortic valve neocuspidization (AVNeo) procedure has emerged as a versatile alternative strategy in the armamentarium of pediatric aortic valve reconstructions that are currently available. In this review article, the focus of the discussion will be on the various aortic valve repair procedures in the pediatric population, with a special emphasis on the emerging role of AVNeo procedure in pediatrics and its outcomes.

Total anomalous pulmonary venous connection with another major congenital cardiac defect in biventricular hearts.

BACKGROUND: The association of total anomalous pulmonary venous connection (TAPVC) with major congenital cardiac anomalies is rare. This coexistence has an impact on the diagnosis and management strategies. The objective of this single centre study was to analyse the outcomes of such association in bi-ventricular hearts. METHODS: This is a single-centre retrospective review of all patients who underwent repair for TAPVC associated with major congenital cardiac anomalies in bi-ventricular hearts from February 2015 to March 2020. Data were obtained from the hospital database. The primary aim was to assess the surgical outcomes. In addition, we described the incidence, pathophysiology, morphology and surgical strategies in this cohort of patients. RESULTS: Out of a total of 274 patients who underwent repair for TAPVC during the study period, 16 (5.8%) patients had one or more major associated cardiac defect anomalies. The major associated lesions were ventricular septal defects (9), tetralogy of Fallot (2), transposition of the great arteries (1), aorto-pulmonary window (1), partial atrioventricular canal defect (1), pulmonary stenosis (1) and severe tricuspid valve regurgitation due to flail chord (1). The mean follow-up period is 32 ± 13 months. There were two deaths in the post-operative period and no deaths in the follow-up period. CONCLUSION: The incidence of major associated cardiovascular defects with TAPVC in bi-ventricular morphology is 5.8%. The presence of a major associated lesion with TAPVC significantly alters the pathophysiology and clinical presentation with an impact on diagnosis and treatment.

Double outlet left atrium: successful management of a rare entity.

Double-outlet left atrium is an extremely rare congenital ventriculo-atrial mal-alignment anomaly, wherein, the left atrium drains into both ventricles, through either a common atrioventricular valve or two separate atrioventricular valves. The only egress from the right atrium is through an inter-atrial communication. We present a 16-month-old male, diagnosed to have double outlet left atrium and describe its surgical management.

Experience with surgical correction of double outlet both ventricles.

Double outlet both ventricles is a rare abnormal ventriculo-arterial malformation in which both great arterial trunks are committed to both the ventricles, albeit now being recognized with increasing frequency. Patients with the lesion present with a spectrum of clinical manifestations. The size and location of the interventricular communication dictate the feasibility of biventricular repair. Literature on the malformation, however, is sparse. We report our experience with five patients, all of whom underwent successful surgical biventricular repair.

Surgical Outcomes of Post-myocardial Infarction Ventricular Septal Defect/Rupture: A Systematic Review and Meta-Analysis.

Ventricular septal defect (VSD) is a catastrophic acute myocardial infarction (MI) complication. Despite a significant reduction in the prevalence of post-MI VSD with the advancement of surgical techniques, it is still considered fatal with a high mortality rate. The trends in the clinical outcomes of patients with post-MI VSD show discretion due to the complexity of the disease. Therefore, the present analysis aimed to evaluate the surgical outcomes and associated risks in the patients of post-MI VSD. A thorough literature survey resulted in 40 studies of our interest. The pooled proportion of differential variables, including the incidence of cardiogenic shock, 30-day survival, and overall mortality, were estimated using Bayesian hierarchical models. The risk difference was estimated for the location of MI and VSD and mortality in patients with coronary artery bypass graft (CABG). In addition, the heterogeneity tests for inconsistency and publication biases using Egger's and Begg's tests were also estimated. The analysis revealed a significant risk difference of 0.23 and 0.27 for the anterior vs. posterior location of MI and VSD, respectively. Further, the pooled proportion of 30-day survival and mortality was found to be 54.43% (95% credible interval (CI): 52.88-55.98%) and 48.22% (95% CI: 4-12.3%), respectively. Moreover, the heterogeneity test revealed significant inconsistencies in all the datasets with an I2 index of >90% (p<0.0001). Lastly, the publication bias results suggested no evidence of asymmetry and small-study effects. Conclusively, the surgical management of post-MI VSD patients is considered beneficial; however, the outcomes signify its fatal behavior.

Intrapulmonary artery septation for pulmonary artery growth in functionally univentricular hearts.

The pulmonary artery anatomy is one of the important determinants of Fontan completion and its outcomes in patients with functionally univentricular hearts. Despite several modifications to Fontan operation, unbalanced pulmonary arteries pose a significant challenge in this subset of patients. Intrapulmonary artery septation is a technique, developed to rehabilitate the unilateral hypoplastic pulmonary artery following various initial palliative procedures in functionally univentricular hearts. Literature is sparse on this technique. This article reviews the basic concepts and literature on intrapulmonary artery septation. We also describe our experience with modified intrapulmonary artery septation.

Double aortic arch with atretic proximal left arch.

Aortic arch anomalies are rare and represent about 1% of all congenital cardiac lesions. Double aortic arch with atretic proximal left arch is one of the rare causes of respiratory symptoms in neonates, often missed by preoperative imaging studies. Preoperative identification and differentiating this entity from other arch anomalies is imperative to plan appropriate surgical management.

Circumflex aorta: An uncharted territory.

BACKGROUND: Vascular rings are aortic arch anomalies with a spectrum of manifestations ranging from asymptomatic lesions detected incidentally to an acute presentation secondary to tracheo-esophageal compression. Circumflex retro-esophageal aortic arch is an extreme form of true vascular ring. It remains an uncharted territory to many surgeons. METHODS: A comprehensive search of peer reviewed journals was completed based on the key words, "Circumflex aorta," "Circumflex retro-esophageal aorta" and "circumflex arch" using Google scholar, Scholars Portal Journals and PubMed. The reference section for each article found was searched to obtain additional articles. Literature on the circumflex aorta was reviewed starting from the embryogenesis to the latest management strategies. RESULTS: Right circumflex aorta is more prevalent compared to left circumflex aorta. It can occur in isolation or in association with other intracardiac lesions. Mainly presents in children, however reported in adults too. The presentation may vary from asymptomatic lesion to acute respiratory distress secondary to airway compression. Computerized tomography (CT) and magnetic resonance imaging (MRI) are important tools in delineating the vascular anatomy. Aortic uncrossing is the definitive procedure. However, the role of concomitant tracheobronchopexy is emerging. Native tissue-to-tissue anastomosis is commonly preferred, but cases of extra-anatomic grafts are reported. CONCLUSION: Circumflex aorta is amenable to complete repair. Preoperative delineation of anatomy is important for successful surgical outcome. Division of the retro-esophageal segment is crucial in relieving the compressive symptoms. In addition, tracheobronchopexy is helpful in addressing residual tracheomalacia but this accounts for a high-risk surgery.

Aortic valve neocuspidization for aortic regurgitation associated with ventricular septal defect.

OBJECTIVES: Different methods of aortic valve repair have been described in the literature for aortic regurgitation (AR) associated with doubly committed subarterial ventricular septal defects. Our goal was to present our experience with aortic valve reconstruction of a single leaflet using the aortic valve neocuspidization technique in this subset of patients. METHODS: It is a retrospective review of 7 patients with doubly committed subarterial ventricular septal defects with significant (>moderate) AR who underwent the single-leaflet neocuspidization technique of aortic valve reconstruction from January 2016 to January 2019. Data were collected from medical records. All patients had thorough 2-dimensional echocardiographic assessment preoperatively and during the follow-up period. Primary end points were freedom from postoperative AR and freedom from reoperation and all-cause mortality within the follow-up period with secondary end points of freedom from thromboembolism and infective endocarditis. RESULTS: Out of 7 patients, 6 were male and 1 was female. There were no perioperative deaths. The mean follow-up period was 2.6 ± 0.8 years. No deaths occurred during the follow-up period. At the latest follow-up examination, only 2 patients showed mild AR and were asymptomatic. There was no documented event of infective endocarditis or thromboembolism during the follow-up period. CONCLUSIONS: The aortic leaflet neocuspidization procedure for the aortic valve is a relatively new concept. Availability of a template makes it an easily reproducible valve repair in paediatric patients with a single-leaflet abnormality. This technique preserves the remaining 2 normal leaflets, thus promoting the growth potential while maintaining near normal aortic root complex dynamics.

Relieving bronchial compression due to cardiomegaly: The role of aortopexy when left ventricular assist device support just is not enough.

Enlarged cardiac structures, especially those on left side have the potential to cause airway compression in pediatric patients with chronic heart failure, owing to their proximity to and impact on the trachea-bronchial tree. Ventricular assist devices are effective in decompressing such hearts thereby alleviating airway problems. Aortopexy serves as an effective airway decompressive measure in cases with persistent airway compression despite effective cardiac decompression by ventricular assist devices. We report a case of 1-year-old male patient with dilated cardiomyopathy in whom airway compression persisted despite ventricular assist device implantation. Aortopexy was effective in relieving airway compression allowing for subsequent extubation and successful heart transplantation.

Circumflex aortic arch: presentation across various age groups: a case series.

Circumflex aortic arch (CAA) is a rare congenital anomaly where the aortic arch crosses the midline, posterior to the esophagus and trachea, and descends on the contralateral side. If patent ductus arteriosus (PDA) is present, this forms a true vascular ring. CAA can compress the trachea and esophagus leading to a myriad of symptoms which can present at any age. We describe our experience with three patients of the CAA, presenting across different age groups.

Role of intrapulmonary artery septation in univentricular hearts.

The optimal management of functionally univentricular hearts with a significant unbalanced pulmonary blood flow is unclear. The role of cavopulmonary shunt in the rehabilitation of hypoplastic pulmonary arteries is limited. Intrapulmonary artery septation is a technique, wherein a systemic-to-pulmonary artery shunt provides an additional source of blood flow to rehabilitate the hypoplastic pulmonary artery. We report a case of functionally univentricular heart with hypoplastic left pulmonary artery following a cavopulmonary shunt in whom intrapulmonary artery septation resulted in adequate growth of the left pulmonary artery.

Branch pulmonary artery stenosis after arterial switch operation: The effect of preoperative anatomic factors on reintervention.

BACKGROUND: We hypothesized that preoperative patient characteristics and branch pulmonary artery (PA) size might influence the rate of postoperative branch PA reintervention in patients with transposition of the great arteries who undergo the arterial switch operation (ASO). METHODS: The retrospective single-center study included 262 consecutive (2008-2017) newborns who underwent the ASO. Demographic characteristics, echocardiography, and clinical outcomes were reviewed. Competing risk analysis modeled incidence of branch PA reintervention and cause-specific hazard regression for predictors analyses. RESULTS: Median age and weight were 7 (range, 5-11) days and 3.4 (range, 3.1-3.8) kg, respectively. Various types of early branch PA reinterventions (concomitant revision or reintervention during the intensive care unit stay) were required in 28 (10.7%) patients. These patients had prolonged ventilation (P < .001), intensive care unit duration (P < .001), worse right ventricular function (P = .043), and high in-hospital mortality (P = .010). Branch PA dimensions significantly decreased immediately after ASO compared with baseline measurements. The median follow-up duration was 20.8 (range, 0.9-44.7) months. Branch PA reintervention was common among survivors without early reinterventions (9.4%), and even more frequent among those with early reinterventions (25%). Subsequent reintervention (all catheter-based) was necessary for more than one-third of patients after initial branch PA reintervention. The multivariable analysis showed preoperative dimension of the left PA (hazard ratio, 0.527 [95% CI, 0.337-0.823]; P = .005), and right PA (hazard ratio, 0.503 [95% CI, 0.318-0.796]; P = .003) were independently associated with late branch PA reinterventions. CONCLUSIONS: Branch PA reintervention was common and often required surgical or catheter-based reinterventions after ASO. PA branch diameters became significantly smaller after ASO. Smaller preoperative branch PA predicted late branch PA reintervention, indicating a smaller margin of geometrical tolerance to this effect.