Conversion of prior univentricular repairs to septated circulation: Case selection, challenges, and outcomes.

OBJECTIVES: Complex congenital heart defects that present earlier in life are sometimes channelled in the single ventricle pathway, because of anatomical or logistic challenges involved in biventricular correction. Given the long-term functional and survival advantage, and with the surgeons' improved understanding of the cardiac anatomy, we have consciously explored the feasibility of a biventricular repair in these patients when they presented later for Fontan completion. We present a single institution's 10-year experience in achieving biventricular septation of prior univentricular repairs, the technical and physiological challenges and the surgical outcomes. METHODS: Between June 2010 and December 2019, 246 patients were channelized in the single ventricle pathway, of which 32 patients were identified as potential biventricular candidates at the time of evaluation for Fontan palliation, considering their anatomic feasibility. The surgical technique involves routing of the left ventricle to the aorta across the ventricular septal defect, ensuring an adequate sized right ventricular cavity, establishing right ventricle-pulmonary artery continuity and taking down the Glenn shunt with rerouting of the superior vena cava to the right atrium. This is a retrospective study where we reviewed the unique physiological and surgical characteristics of this subset of patients and analysed their surgical outcomes and complications. RESULTS: Biventricular conversion was achieved in all cases except in 3 patients, who had the Glenn shunt retained leading to a one and a half ventricle repair. The average age of the patients was 4.9 years of whom 18 were male. The average cardiopulmonary bypass time was 371 min with an average cross clamp time of 162 min. There was one mortality in a patient with corrected transposition of great arteries (c-TGA) with extensive arterio-venous malformations (AVMs). At a median follow-up of 60 months, all patients remained symptom free except two with NYHA II symptoms, one being treated for branch pulmonary artery stenosis with balloon dilatation and the other with multiple AVMs who needed coil closure. One patient with branch pulmonary artery (PA) stenosis required balloon dilatation and stent placement. CONCLUSION: The possibility of achieving the surgical goal in this unique subset of patients evolves with the progressive experience of the congenital heart surgeon. Case selection is a crucial aspect in achieving the desired outcome, and this 'borderline' substrate is often recognized at the time of evaluation for the Fontan completion. A comprehensive preoperative imaging and planning helps in achieving the surgical septation and reconnection to achieve the desired physiological circulation. Though technically challenging, the surgery has excellent short- and mid-term outcomes as evidenced by our 10-year experience.

Catheter-based palliation for infants with tetralogy of Fallot.

BACKGROUND: The optimal management of symptomatic tetralogy of Fallot in neonates and younger infants with unfavourable anatomy is unclear and is further constrained by resource limitations in low and middle income countries. METHODS: Retrospective medical record review of infants with tetralogy of Fallot undergoing corrective or palliative procedures between January 2016 and June 2019. RESULTS: The study included 120 infants; of whom 83 underwent primary complete repair, four underwent surgical palliation, and 33 underwent catheter-based palliation, including balloon pulmonary valvuloplasty (n = 18), right ventricular outflow tract stenting (n = 14), and stenting of the patent arterial duct (n = 1). Infants undergoing catheter-based procedures were younger in age (median 32 days; inter-quartile range (IQR) 7-144 versus 210 days; IQR 158-250), with lower baseline saturation (65 ± 12% versus 87 ± 7%) and had smaller pulmonary artery z-scores compared to the complete repair cohort. Follow-up was available for 31/33 (94%) infants (median 7 months [IQR 4-11]) who underwent trans-catheter palliation; 12 underwent complete repair, 10 are well, awaiting repair, eight required further palliation (catheter: 6; surgical: 2), and one died post-discharge from non-cardiac causes. CONCLUSION: Catheter-based palliation is a safe and effective alternative in infants with tetralogy of Fallot who are at high risk for primary surgical repair.

Accuracy of a New Echocardiographic Index to Predict Need for Trans-annular Patch in Tetralogy of Fallot.

The long-term outcome after repair of tetralogy of Fallot (TOF) is critically dependent pulmonary valve competence that is compromised by trans-annular patch (TAP). We compared a new echocardiographic index [pulmonary annulus index (PAI)] to conventional methods of predicting need for TAP in infants undergoing TOF repair. Consecutive infants undergoing TOF repair were prospectively studied. Pre-operative aortic and pulmonary annuli and main pulmonary artery (MPA) diameters were measured and z scores determined. PAI was a ratio of observed to expected pulmonary annulus (PA) diameter. TAP was based on intra-operative sizing by surgeons blinded to PAI values. Receiver operator curves (ROC) were generated for all PAI, MPA z scores and pulmonary annulus z scores. Of 84 infants (8.6 ± 2.6 months; 7.5 ± 1.3 kg), 36 needed TAP (43%). All the three indices viz. PAI, Pulmonary annulus and MPA z scores performed similarly in predicting need for TAP (ROC curves ~ 80%). Combining cut-offs of MPA z scores (> - 3.83) with either PAI (> 0.73) or PA z score (> - 1.83) predicted avoidance of TAP with ~ 90% accuracy. When both PAI and MPA z scores were below the cut-offs there was an 80% likelihood of TAP. Failure to predict TAP was associated with unicommisural pulmonary valves. PAI was equal to PA z scores in predicting need for TAP during repair of TOF. Combining either with MPA z scores was the most accurate method of prediction. Failure of prediction was mainly due to presence of a unicommissural pulmonary valve.

Pulmonary venous hypertension may allow delayed palliation of single ventricle physiology with pulmonary hypertension.

Pulmonary vascular disease develops early in untreated single ventricle patients with increased pulmonary flow. Pulmonary artery (PA) banding is done at a young age in these patients in order to protect the lung vasculature and maintain low pulmonary artery pressures (PAP) and pulmonary vascular resistance (PVR). This also enables future completion of the single ventricle palliation. Pulmonary venous hypertension (PVH) secondary to left sided obstruction if present in addition in this setting contributes to the pulmonary arterial hypertension (PAH) but involves an element of reversibility of the PAH if the obstruction is relieved. We present two cases of single ventricle both of who re-presented late with PAH and PVH (secondary to mitral valve obstruction) and underwent delayed PA banding at 9.5 and 4.5 years of age respectively. Both patients however had different outcomes. The patient undergoing PA banding at 9.5 years successfully underwent a cavo-pulmonary shunt at the age of 12 years. The patient with PA banding at 4.5 years however, has residual PAH that presently precludes a cavo-pulmonary shunt.

Anomalous left coronary artery from nonfacing pulmonary sinus: direct aortic reimplantation.

We report a new technique of establishing a direct coronary transfer for anomalous left coronary artery arising from the nonfacing sinus of the pulmonary artery. This easily reproducible technique was successfully used in 2 patients. It achieves a dual coronary repair without the use of complex aortic or pulmonary arterial flaps and without causing any distortion to the great vessels.

Two-ventricle repair for complex congenital heart defects palliated towards single-ventricle repair.

OBJECTIVES: Complex congenital heart defects that present earlier in life are sometimes channelled towards single-ventricle repair, because of anatomical or logistic challenges involved in two-ventricle correction. Given the long-term functional and survival advantage, we have been consciously exploring the feasibility of a biventricular repair in these patients when they present later for Fontan completion. METHODS: Since June 2009, 71 patients were referred for staged completion of the Fontan procedure. Following detailed evaluation that included three-dimensional echocardiography and magnetic resonance imaging, 10 patients (Group 1-median age 6 years) were identified and later underwent complex biventricular repair with takedown of Glenn shunt, while completion of extracardiac Fontan repair was done in 61 patients (Group 2-median age 7 years). RESULTS: Two-ventricle repair was accomplished in all the 10 Group 1 patients. One patient developed complete heart block requiring permanent pacemaker insertion. Late patch dehiscence occurred in another (awaiting repair). At a median follow-up of 15 months, there was no mortality among the Group 1 patients and all except for 1 patient were symptom free. There were 2 early deaths (3.3%) in the Group 2 patients. CONCLUSIONS: Two-ventricular repair, although surgically challenging, should be considered in all patients with two functional ventricles who come for Fontan completion. Comprehensive preoperative imaging and meticulous planning helps in identifying suitable candidates.

Limited right posterior thoracotomy approach to atrial septal defect.

Experience of atrial septal defect closure via a limited posterior thoracotomy is described. From July 1999 to May 2001, 75 prepubertal girls with a median age of 7 years (range, 3 to 13 years) and a median weight of 18 kg (range, 10 to 46 kg) underwent atrial septal defect closure through a limited right posterior thoracotomy. All but 2 patients had an uneventful postoperative recovery. The median duration of ventilation was 13.3 hours (range, 4 to 24 hours). Median hospital stay was 6 days (range, 6 to 8 days). All patients were followed up for 7 to 32 months (mean, 15 months). The wounds healed well without any restriction of limb movement. The limited posterior thoracotomy gave excellent cosmetic results and can be used as a safe alternative approach for atrial septal defect closure in prepubertal females.