Pulmonary artery banding: still a valuable option in developing countries?

Common Arterial Trunk Repair at the Red Cross War Memorial Hospital, Cape Town: A 20-Year Review of Surgical Practice and Outcomes

BACKGROUND

This study describes the 20-year experience of managing common arterial trunk (CAT) in a low-and-middle-income country and compares the early and medium-term outcomes following the transition from conduit to nonconduit repair at the Red Cross War Memorial Children's Hospital.

METHODS

Single-center retrospective study of consecutive patients aged less than 18 years who underwent repair of CAT from January 1999 to December 2018 at the Red Cross War Memorial Children's Hospital. Patients with interrupted aortic arch or previous pulmonary artery banding were excluded.

RESULTS

Fifty-four patients had CAT repair during the study period. Thirty-four (63.0%) patients had a conduit repair, and 20 (37.0%) patients had a nonconduit repair. There were two intraoperative deaths. Thirty-day in-hospital mortality was 22.2% (12/54). Overall, in-hospital mortality was 29.6% (16/54). Eight (21.1%) late mortalities were observed. The actuarial survival for the conduit group was 77.5%, 53.4%, and 44.5% at 6, 12, and 27 months, respectively, and the nonconduit group was 58.6% at six months. The overall freedom from reoperation between the conduit group and nonconduit group was 66.2% versus 86.5%, 66.2% versus 76.9%, and 29.8% versus 64.1% at 1, 2, and 8 years, respectively.

CONCLUSIONS

The outcomes following the transition to nonconduit repair for CAT in a low- and middle-income setting appear to be encouraging. There was no difference in mortality between conduit and nonconduit repairs, and importantly the results suggest a trend toward lower reintervention rates.

Pulmonary artery banding: still a role for staged bi-ventricular repair of intracardiac shunts?

OBJECTIVES

Although pulmonary artery banding remains a useful palliation in bi-ventricular shunting lesions, single-stage repair holds several advantages. We investigate outcomes of the former approach in high-risk patients.

METHODS

Retrospective cohort study including all pulmonary artery banding procedures over 9 years, excluding single ventricle physiology and left ventricular training.

RESULTS

Banding was performed in 125 patients at a median age of 41 days (2-294) and weight of 3.4 kg (1.8-7.32). Staged repair was undertaken for significant co-morbidity in 81 (64.8%) and anatomical complexity in 44 (35.2%). The median hospital stay was 14 days (interquartile range 8-33.5) and 14 patients (11.2%) required anatomical repair before discharge. Nine patients died during the initial admission (hospital mortality 7.2 %) and five following discharge (inter-stage mortality 4.8%). Of 105 banded patients who survived, 19 (18.1%) needed inter-stage re-admission and 18 (14.4%) required unplanned re-intervention. Full repair was performed in 93 (74.4%) at a median age of 13 months (3.1-49.9) and weight of 8.5 kg (3.08-16.8). Prior banding, 54% were below the 0.4th weight centile, but only 28% remained so at repair. Post-repair, 5/93 (5.4%) developed heart block requiring permanent pacemaker, and 11/93 (11.8%) required unplanned re-intervention. The post-repair mortality (including repairs during the initial admission) was 6/93 (6.5%), with overall mortality of the staged approach 13.6% (17/125).

CONCLUSIONS

In a cohort with a high incidence of co-morbidity, pulmonary artery banding is associated with a significant risk of re-intervention and mortality. Weight gain improves after banding, but heart block, re-intervention, and mortality remain frequent following repair.

Congenital Heart Disease in Low- and Lower-Middle-Income Countries: Current Status and New Opportunities

PURPOSE OF REVIEW

The paper summarises the most recent data on congenital heart disease (CHD) in low- and lower-middle-income countries (LLMICs). In addition, we present an approach to diagnosis, management and interventions in these regions and present innovations, research priorities and opportunities to improve outcomes and develop new programs.

RECENT FINDINGS

The reported birth prevalence of CHD in LLMICs is increasing, with clear evidence of the impact of surgical intervention on the burden of disease. New methods of teaching and training are demonstrating improved outcomes. Local capacity building remains the key. There is a significant gap in epidemiological and outcomes data in CHD in LLMICs. Although the global agenda still does not address the needs of children with CHD adequately, regional initiatives are focusing on quality improvement and context-specific interventions. Future research should focus on epidemiology and the use of innovative thinking and partnerships to provide low-cost, high-impact solutions.

Management of undernutrition and failure to thrive in children with congenital heart disease in low- and middle-income countries

Poor growth with underweight for age, decreased length/height for age, and underweight-for-height are all relatively common in children with CHD. The underlying causes of this failure to thrive may be multifactorial, including innate growth potential, severity of cardiac disease, increased energy requirements, decreased nutritional intake, malabsorption, and poor utilisation of absorbed nutrition. These factors are particularly common and severe in low- and middle-income countries. Although nutrition should be carefully assessed in all patients, failure of growth is not a contraindication to surgical repair, and patients should receive surgical repair where indicated as soon as possible. Close attention should be paid to nutritional support - primarily enteral feeding, with particular use of breast milk in infancy - in the perioperative period and in the paediatric ICU. This nutritional support requires specific attention and allocation of resources, including appropriately skilled personnel. Thereafter, it is essential to monitor growth and development and to identify causes for failure to catch-up or grow appropriately.

Medical missions for the provision of paediatric cardiac surgery in low- and middle-income countries

This review will outline the role of visiting cardiac surgical teams in low- and middle-income countries drawing on the collective experience of the authors in a wide range of locations. Requests for assistance can emerge from local programmes at a beginner or advanced stage. However, in all circumstances, careful pre-trip planning is necessary in conjunction with clinical and non-clinical local partners. The clinical evaluation, surgical procedures, and postoperative care all serve as a template for collaboration and education between the visiting and local teams in every aspect of care. Education focusses on both common and patient-specific issues. Case selection must appropriately balance the clinical priorities, safety, and educational objectives within the time constraints of trip duration. Considerable communication and practical challenges will present, and clinicians may need to make significant adjustments to their usual practice in order to function effectively in a resource-limited, unfamiliar, and multilingual environment. The effectiveness of visiting trips should be measured and constantly evaluated. Local and visiting teams should use data-driven evaluations of measurable outcomes and critical qualitative evaluation to repeatedly re-assess their interim goals. Progress invariably takes several years to achieve the final goal: an autonomous self-governing, self-financed, cardiac programme capable of providing care for children with complex CHD. This outcome is consistent with redundancy for the visiting trips model at the site, although fraternal, professional, and academic links will invariably remain for many years.

Feasibility and related outcome of intraluminal pulmonary artery banding

OBJECTIVES

This retrospective study evaluated the feasibility and related outcome of intraluminal pulmonary artery banding (I-PAB).

METHODS

Thirty-two children underwent I-PAB between July 2006 and April 2014. The median age and weight were 60 days (range: 5 days to 4.2 years) and 3.7 kg (range: 2.6-13.0 kg), respectively. Cardiac diagnoses included single ventricle morphology (n = 11), complex ventricular septal defects (n = 11), balanced atrioventricular septal defects (n = 3), congenitally corrected transposition of the great arteries (n = 2) and aortic arch hypoplasia with ventricular septal defects (n = 5). On cardiopulmonary bypass (CPB), 2 I-PAB modifications with either 1 (n = 24) or 2 ('hour-glass-technique', n = 8) fenestrated pericardial patches were performed.

RESULTS

The median fenestration size was 5 mm (range: 4-6.5 mm). In 18 patients I-PAB was a solitary procedure; in 3 of them the decision was made intraoperatively. There was no hospital mortality. The median interval to debanding was 189 days (range: 112 days to 2.6 years). During this period, we observed a significant increase in the pressure gradient over I-PAB (P < 0.01), whereas arterial saturations remained stable. Four patients received balloon dilatation of I-PAB to prolong the palliation period. No patient experienced band occlusion, pulmonary hypertension related to I-PAB, coronary or pulmonary valve impairment. Debanding was performed in 27 patients and one of them required pulmonary patch arterioplasty due to I-PAB-associated pulmonary trunk distortion. Three patients are still awaiting further surgery. There were 2 late deaths prior to, and 3 after debanding, all not related to I-PAB.

CONCLUSIONS

I-PAB with an exactly defined internal orifice is feasible and effective. Although arterial saturations seem to remain stable, balloon dilatation of I-PAB can be performed safely and efficiently in order to prolong the palliation period. The rate of I-PAB-related complications is low, which might improve the long-term patient outcome. Therefore, despite requiring CPB, I-PAB is our institutional preference for children who require pulmonary artery banding.

Repair of congenital heart disease with associated pulmonary hypertension in children: what are the minimal investigative procedures? Consensus statement from the Congenital Heart Disease and Pediatric Task Forces, Pulmonary Vascular Research Institute (PVRI)

Standardization of the diagnostic routine for children with congenital heart disease associated with pulmonary arterial hypertension (PAH-CHD) is crucial, in particular since inappropriate assignment to repair of the cardiac lesions (e.g., surgical repair in patients with elevated pulmonary vascular resistance) may be detrimental and associated with poor outcomes. Thus, members of the Congenital Heart Disease and Pediatric Task Forces of the Pulmonary Vascular Research Institute decided to conduct a survey aimed at collecting expert opinion from different institutions in several countries, covering many aspects of the management of PAH-CHD, from clinical recognition to noninvasive and invasive diagnostic procedures and immediate postoperative support. In privileged communities, the vast majority of children with congenital cardiac shunts are now treated early in life, on the basis of noninvasive diagnostic evaluation, and have an uneventful postoperative course, with no residual PAH. However, a small percentage of patients (older at presentation, with extracardiac syndromes or absence of clinical features of increased pulmonary blood flow, thus suggesting elevated pulmonary vascular resistance) remain at a higher risk of complications and unfavorable outcomes. These patients need a more sophisticated diagnostic approach, including invasive procedures. The authors emphasize that decision making regarding operability is based not only on cardiac catheterization data but also on the complete diagnostic picture, which includes the clinical history, physical examination, and all aspects of noninvasive evaluation.

Systemic-pulmonary artery shunts in infants: modified Blalock-Taussig and central shunt procedures

Access is gained through a midline sternotomy, the thymus partially excised and the superior part of the pericardium is opened. The innominate vein is retracted and the innominate artery is mobilized up to the bifurcation. The aorta is retracted to the left, the superior vena cavae to the right and the right atrial appendage inferiorly. The adventitia around the right pulmonary artery (PA) is dissected, taking care to incise the bulky pericardial reflection between the superior vena cavae and the trachea. Heparin is administrated. An occlusive clamp is applied to the right PA to test for haemodynamic tolerance prior to proceeding with the interposition of a suitable size artificial vascular prosthesis, based on the weight of the patient, between the innominate artery, or proximal subclavian artery and the right PA. Alternatively, if a sufficient main PA is present and adequate flow from a patent ductus arteriosus an end-to-side interposition shunt may be constructed between the ascending aorta and the main PA, provided the patient is stable with the test occlusion of the main PA. The management of the patent arterial ductus depends on whether or not there is forward flow through the PA.

Pulmonary artery banding

Pulmonary artery banding (PAB) is a simple surgical technique to reduce pulmonary overcirculation in some congenital heart disease. In the beginning, when the use of cardiopulmonary bypass was affected by many deleterious effects, this technique played a fundamental role in the treatment of patients with congenital heart defects and an intracardiac left-to-right shunt. The use of PAB has decreased during the last two decades, due to the increasing popularity of early complete intracardiac repair, which results have shown to be superior to staged repair, even in low body weight patients. Moreover, several authors have emphasized the negative effects of PAB such as pulmonary arterial branch distortion, abnormal right ventricular hypertrophy, pulmonary valve insufficiency, sub-aortic obstruction and decreased ventricular compliance in patients with univentricular heart. For all these reasons, this procedure has been placed in the dark corner of surgery, representing, between 2002 and 2005, ∼2% of the total amount of cardiac surgery procedures. In a more recent era, PAB has been performed in instances other than classic univentricular heart, as palliation in small infants with cardiac defects with a left-to-right shunt and pulmonary overcirculation, thus gaining some time prior to a planned staged repair. Recently, the role of PAB is becoming more important in selected subsets of congenital cardiac defects: L-transposition of the great arteries, D-transposition of the great arteries, hypoplastic left heart syndrome, moderately hypoplastic left ventricle (congenitally corrected transposition of the great arteries). This renewed interest in the banding procedure is spurring all surgeons and cardiologists to find new solutions for an easier banding procedure while making debanding less traumatic.

A comprehensive review: the evolution of animal models in pulmonary hypertension research; are we there yet?

Pulmonary hypertension (PH) is a disorder that develops as a result of remodeling of the pulmonary vasculature and is characterized by narrowing/obliteration of small pulmonary arteries, leading to increased mean pulmonary artery pressure and pulmonary vascular resistance. Subsequently, PH increases the right ventricular afterload, which leads to right ventricular hypertrophy and eventually right ventricular failure. The pathophysiology of PH is not fully elucidated, and current treatments have only a modest impact on patient survival and quality of life. Thus, there is an urgent need for improved treatments or a cure. The use of animal models has contributed extensively to the current understanding of PH pathophysiology and the investigation of experimental treatments. However, PH in current animal models may not fully represent current clinical observations. For example, PH in animal models appears to be curable with many therapeutic interventions, and the severity of PH in animal models is also believed to correlate poorly with that observed in humans. In this review, we discuss a variety of animal models in PH research, some of their contributions to the field, their shortcomings, and how these have been addressed. We highlight the fact that the constant development and evolution of animal models will help us to more closely model the severity and heterogeneity of PH observed in humans.

Congenital heart disease and rheumatic heart disease in Africa: recent advances and current priorities

Africa has one of the highest prevalence of heart diseases in children and young adults, including congenital heart disease (CHD) and rheumatic heart disease (RHD). We present here an extensive review of recent data from the African continent highlighting key studies and information regarding progress in CHD and RHD since 2005. Main findings include evidence that the CHD burden is underestimated mainly due to the poor outcome of African children with CHD. The interest in primary prevention for RHD has been recently re-emphasised, and new data are available regarding echocardiographic screening for subclinical RHD and initiation of secondary prevention. There is an urgent need for comprehensive service frameworks to improve access and level of care and services for patients, educational programmes to reinforce the importance of prevention and early diagnosis and a relevant research agenda focusing on the African context.