Stage one Norwood procedure results: the green lane experience

Aims: This study examined the presentation outcome, morbidity and mortality of infants who have undergone the stage one Norwood procedure for single ventricle reconstruction.

Methods: A retrospective review was done on the first 20 patients to undergo this procedure at Green Lane Hospital, Auckland, New Zealand. Seven patients were diagnosed antenatally. Fetal cardiology records in the same time period were reviewed.

Results: Twelve of the 20 patients (60%) have survived, and all of these patients have undergone their bi-directional Glenn procedure with no mortality. Eight patients died, with five of the deaths occurring in the perioperative period. Initial surgical mortality was 75%, decreasing to 25% since 1998. Antenatal diagnosis has not improved surgical outcome to date.

Conclusion: With advances in surgical technique and pre- and postoperative care, neonates born with single ventricle anatomy have an acceptable surgical option. Babies who survive the Norwood operation have a good chance of surviving the later stages of the cardiac reconstruction process, and they have a reasonable outlook in the intermediate term.     

Subaortic membrane excision: mid-term results

Background: Subaortic membrane (SAM) is a form of fixed subaortic obstruction in which a fibrous membrane is located below the aortic valve.

Aim: To determine the role of surgical treatment for patients with a discrete SAM.

Patients and Methods: The hospital records of 45 patients (age range: 2–23 years; median 8 years) undergoing surgery for SAM between 1990 and 1998 at the All India Institute of Medical Sciences, New Delhi, India, were analysed. Preoperative echocardiographically calculated gradients across the left ventricular outflow tract ranged from 50 to 154 mmHg (mean: 86.5 ± 33.2 mmHg). Nine patients had trivial aortic regurgitation (AR), 10 had mild AR and five had moderate-severe AR. The left ventricular ejection fraction (LVEF) ranged from 20 to 68% (mean 48 ± 15%). Nineteen patients had significant left ventricular dysfunction (LVEF <50%). Transaortic resection of SAM was done in all patients along with excision of a wedge-shaped segment of septal muscle underlying the membrane.

Results: There were no early or late postoperative deaths. On follow up (up to 113 months), only four patients had gradients >30 mmHg. LVEF improved to 45–70% (mean 58 ± 7.7%). AR reduced to mild in four patients and trivial in four patients, and did not progress further.

Conclusion: Resection of SAM carries long-term benefits. Routine septal myectomy appears to be associated with a low risk of recurrence.     

Alternative approach for angioplasty of stenosed left pulmonary artery following intracardiac repair of tetralogy of Fallot

A 5-year-old boy with stenosed left pulmonary artery following total correction of tetralogy of Fallot underwent surgical pulmonary arterioplasty through a left anterolateral thoracotomy on a normothermic perfused heart under cardiopulmonary bypass. We found this to be a convenient approach, and recommend it for correction of this lesion in the absence of gross pulmonary regurgitation and right ventricular outflow tract dilatation.     

Viable extracardiac total right heart bypass: technical considerations and mid-term results

BACKGROUND: Direct connection of both caval veins to the pulmonary arterial system would be the ideal right heart bypass by virtue of elimination of prosthetic material and extensive atrial suture lines. However, it can be applied only to selected patients with peculiar anatomical arrangements. We decided to perform total extracardiac right heart bypass using pedicled in situ pericardium in situations when a direct connection was not possible. METHODS: A cohort of five patients, aged 3.5, 4, 10, 10 and 31 years, respectively, with complex cyanotic congenital heart diseases were candidated to extracardiac total cavopulmonary connection using viable in situ pericardium. Aortic cross-clamp was completely avoided in all patients. RESULTS: There was no early or late death. Postoperatively, all patients are in functional class I and in normal sinus rhythm at a mean follow-up of 30 months (S.D.=+/-19 months). Postoperative serial echocardiograms revealed wide, unrestricted anastomoses, unobstructed venous flow to both pulmonary arteries with cardiac pulsations and respiratory variations in the pulmonary arteries due to compressible lateral tunnel. Cavopulmonary angiograms (n=5) in late postoperative period have demonstrated a smooth, nonturbulent, somewhat pulsatile flow without pressure gradient. CONCLUSIONS: The technical advantages and haemodynamic benefits of this operation are encouraging. A longer follow-up is needed to confirm the early results, especially late atrial dysrrhythmias, pulmonary venous obstruction, thromboembolic complications and growth of the conduit.     

Blalock-Taussig shunt: experience from the developing world

Background: Palliative procedures have a role in congenital cardiac malformations that do not permit a complete early repair, and in centres where facilities for complete early repair do not exist. The lack of data on modified Blalock-Taussig shunt from developing countries prompted this analysis.

Methods: We report a retrospective study of 70 Blalock-Taussig shunt procedures in 63 patients over an 8-year period. Most of the procedures (54.0%) were done on children less than 4 months of age. Thirty-nine (58%) patients had Tetralogy of Fallot; the remaining patients had a wide spectrum of lesions.

Results: In the first year of the review period, the classical Blalock-Taussig shunt was done in six patients (9.5%) and the modified Blalock-Taussig shunt was used thereafter. In 49 patients who were followed up long term, clinical congestive cardiac failure developed in three (6%) and shunt failure was reported in 10 (14%). Of the 16 (33%) total deaths, six had serious comorbid conditions preoperatively.

Conclusions: The Blalock-Taussig shunt is a relatively safe palliative procedure, requiring fewer resources and less expertise than corrective surgery, making it a suitable option in developing countries.     

小于4岁先天性心脏病患儿急诊手术41例临床报告

目的 探讨婴幼儿先天性心脏病急诊手术原因及疗效。方法 收集我院外科1998年1月-2000年11月收治的41例小于4岁的患儿资料。分析急诊心脏手术的原因及手术效果。结果 41例患儿中，法鲁四联症25例，房间隔缺损合并肺动脉瓣狭窄5例。完全型肺静脉异位引流4例。大动脉转位2例，室间隔缺损合并肺动脉高压3例。三尖瓣闭锁合并室间隔缺损1例，室间隔缺损合并右室赘生物1例。院内手术死亡7例。死亡率17.1%。结论 病情危重，内科治疗效果不佳的先天性心脏病患儿接受急诊手术治疗，可以取得较好效果。     

Endogenous cardiac opioids: enkephalins in adaptation and protection of the heart

Opiates have been used for thousands of years in the form of opium for relief of pain or fever and to induce sleep. However, it was only in the 1970s that the endogenous ligands for the opiate receptors were identified and termed opioid peptides. Opioid peptides activate G protein-coupled receptors in the central and autonomic nervous system, with marked effects on the regulation of pain perception, body temperature, respiration, heart rate and blood pressure. Cardiovascular regulatory effects of endogenous opioids were initially considered to originate from neural centres in the central nervous system, facilitating a regulatory role in neuro-transmission, as demonstrated by the presynaptic co-release from sympathetic neurones of norepinephrine with enkephalin or acetylcholine with enkephalin. However, opioid peptides of myocardial origin have also recently been shown to play a key role in local regulation of the heart. This brief review highlights the key features of the enkephalin opioids in the heart and the current understanding of their role in development, ageing, cardioprotection, hypertension, hypertrophy, and heart failure.     

Dyspnoea and exercise intolerance during cardiopulmonary exercise testing in patients with univentricular heart: The effects of chronic hypoxaemia and Fontan procedure

BACKGROUND: Patients with univentricular hearts have decreased exercisetolerance and may demonstrate exertional dyspnoea. It is notknown if chronic hypoxaemia exacerbates exercise intoleranceand contributes to symptomatic limitation. The extent to whichsurgical correction of a right-to-left shunt by a Fontan-typeprocedure can increase exercise tolerance by reducing arterialdeoxygenation is not well documented. The cardiopulmonary exerciseresponses and the symptomatic status in two groups of univentricularpatients, those who are cyanotic and those who are acyanoticwith Fontan-type circulation, were compared. METHODS AND FINDINGS: Cardiopulmonary exercise testing was performed in 10 univentricularpatients with rest or stress-induced cyanosis (age 30·5±2·3[SE] years; 5 men) who had palliative or no surgery and eightpatients (age 29·4±1·5 years; 4 men) withFontan-type circulation. Peak oxygen consumption was comparablein both groups of univentricular patients (21·7±2·5vs 21·0±1·9 ml. kg^–1 . min^–1,P=0·85) but was less than an age-matched group of 10healthy subjects (34·7±1·9 ml. kg^–1. min^–1, P<0·001 for both). Arterial oxygensaturation was 90·6% at rest in the cyanotic patientscompared with 95·1% in the Fontan patients (P<0·001)and at peak exercise, 66·2% compared with 90·5%(P<0·001). Using a modified Borg scale (0–10),the symptoms of dyspnoea and fatigue were also assessed duringexercise in the patient groups. The Borg scores for dyspnoeain the cyanotic and the corrected univentricular patients were,respectively, as follows: Stage 1: 0·5 vs 1·7;P=0·04; Stage 2: 1·8 vs 2·3, P=0·5;Stage 3: 3·0 vs 3·5, P=0·7; Peak Exercise:4·9 vs 4·8, P=0·9. In addition, the Borgscores for fatigue were: Stage 1: 0·4 vs 1·6,P=0·08; Stage 2: 2·0 vs 2·2, P=0·9;Stage 3: 3·0 vs 4·3, P=0·5; Peak Exercise:4·9 vs 5·4, P=0·5. The major limiting symptomat peak exercise was dyspnoea in four cyanotic patients comparedwith one in the Fontan group (Chi-square 0·982, P>0·10).The arterial oxygen desaturation at peak exercise in the cyanoticpatients limited by dyspnoea was not different from those limitedby fatigue (67·5±10·1% vs 66·7±13·7%,P=0·92). Exercise tolerance was also not related to thearterial oxygen saturation at peak exercise (r=0·47,P=0·17) in these patients. CONCLUSION: Despite correction with Fontan-type surgery, the exercise toleranceand symptoms of these univentricular patients remained similarto those who were cyanosed. Cyanotic patients have adjustedto chronic hypoxaemia and it does not appear to determine theexercise tolerance or the genesis of dyspnoea in these patients.Further randomized prospective studies are required to investigatethe long-term benefits of Fontan-type procedures in these patientson exercise tolerance, symptoms and prognosis.     

Five decades of the Fontan operation: A systematic review of international reports on outcomes after univentricular palliation

Almost fifty years after its first clinical application, the modified Fontan operation is among the most frequently performed procedures in congenital heart disease surgery in children today. The objective of this review is to systematically summarize the international evolution of outcomes in regard to morbidity and mortality of patients with Fontan palliation. All studies published over the past five decades with more than 100 Fontan patients included were screened. In eligible studies, information concerning preoperative patients' characteristics, Fontan modifications employed, early mortality, long‐term survival and frequency of relevant complications was extracted. Ultimately, thirty‐one studies published by the largest surgical centers with an overall number of 9390 patients were included in this review. The extracardiac total cavopulmonary anastomosis is the most frequently used Fontan modification. Hemodynamic data demonstrate a rigorous overall adherence to suggested Fontan selection criteria. The analysis showed a clear trend toward improved early and long‐term survival over the time period covered. Although inconsistently reported, severe complications such as arrhythmias, thromboembolic events and protein‐losing enteropathy as well as reoperations and reinterventions were frequent. In conclusion, patients palliated for complex univentricular heart malformations nowadays benefit from the experience and technical developments of the past decades and have a significantly improved long‐term prognosis. However, important issues concerning postoperative long‐term morbidity and mortality are still unsolved and clear intrinsic limitations of the Fontan circulation are becoming evident as the population of Fontan patients ages.     

Focal liver lesions following Fontan palliation of single ventricle physiology: A radiology‐pathology case series

Purpose: Patients who have undergone Fontan palliation of single ventricle physiol‐ ogy congenital heart disease are prone to developing focal liver lesions. In our experi‐ ence, the variety of lesions occurring in this population is greater than that described in the literature. The purpose of this study was to describe the breadth of biopsy‐ proven liver lesions in patients post–Fontan palliation of single ventricle physiology cared for at our institution.
Methods: We retrospectively identified patients who had previously undergone the Fontan operation and had a focal liver lesion biopsied between January 2000 and June 2018. Medical records were reviewed for lesion pathology, background liver findings, pertinent laboratory data, and demographic data. CT and MRI images were reviewed to describe imaging findings of the reported lesions.
Results: Twelve patients met inclusion criteria; 58% (7/12) of which were female. Fifteen lesions were biopsied including four macroregenerative/benign hepatocellu‐ lar hyperplastic nodules, two hepatocellular adenomas, two hepatocellular carcino‐ mas, two intrahepatic cholangiocarcinoma (in the same patient), one venous malformation, and one focus of vascularized scar tissue. Two additional lesions in patients postcardiac transplant were posttransplant lymphoproliferative disorder.
Conclusion: Patients who have undergone Fontan palliation of single ventricle physi‐ ology are prone to develop a variety of liver lesions, both benign and malignant.     

“Frontiers in Fontan failure: A summary of conference proceedings”

“Frontiers in Fontan Failure” was the title of a 2015 conference sponsored by Children's Healthcare of Atlanta and Emory University School of Medicine. In what is hoped to be the first of many such gatherings, speakers and attendees gathered to discuss the problem of long‐term clinical deterioration in these patients. Specific focuses included properly defining the problem and then discussing different treatment strategies, both medical and surgical. The health of the liver after Fontan palliation was a particular point of emphasis, as were quality of life and future directions.     

Ventilatory threshold during exercise in patients with mild to moderate chronic heart failure: determination, relation with lactate threshold and reproducibility

Detection of the ventilatory threshold during exercise has been proposed in order to assess exercise tolerance in patients with chronic heart failure. The relation between the different methods of detecting the ventilatory threshold and the lactate threshold, however, and their reproducibility, have not really been assessed. Forty-three patients with chronic heart failure underwent an exercise test with respiratory gas analysis. A lactate threshold could be determined in 36 patients and a ventilatory threshold in 27 to 38 patients, depending on the method of determination of the ventilatory threshold. The greatest number of determinations (38) and the best correlation coefficient with the lactate threshold (r = 0.87 and 0.88, respectively) were obtained with the method of the ventilatory equivalent for oxygen and by averaging the different methods of determination. Reproducibility of the ventilatory threshold was only moderately good (r = 0.83) and less satisfactory than that of the peak oxygen uptake (r = 0.97). We conclude that unless the way of detecting the ventilatory threshold is improved in patients with chronic heart failure, the peak oxygen uptake will remain more reproducible.     

Associations between Bodyweight and Clinical Outcome in Patients Post-Fontan Procedure: A Systematic Review

Background: Patients born with a single ventricle circulation commonly experience growth failure in early life, which is associated with adverse outcomes in infancy. However, associations between bodyweight or weight trajectory and clinical outcome post-Fontan procedure are yet to be determined. Methods: On the 1st of July 2021, a systematic review was performed in MEDLINE, EMBASE, the Cochrane Library, and Scopus of studies of patients with clinical outcome data post-Fontan procedure and association with bodyweight. Quality of studies was evaluated by Newcastle–Ottawa scale for cohort studies and Joanna Briggs Institute tool for cross-sectional studies. Results: Of 527 studies that underwent title and abstract screening, 15 were selected for final review. An increased risk of adverse post-Fontan outcomes was found for low weight patients, consistent with findings in infants. Whilst there is some evidence to suggest increased mortality in overweight adult patients, studies are conflicting as to whether overweight status is associated with increased heart failure. Increased BMI is associated with diminished exercise capacity and deceased physiological functioning. Negative weight trajectory is associated with adverse outcomes in the peri-Fontan period, whereas a positive weight trajectory is associated with increased Fontan failure in adulthood. Abnormal BMI (high or low) is associated with increased heart failure and poorer performance in quality-of-life scores. Conclusions: Bodyweight is a modifiable risk factor for poor clinical outcome in patients with a single ventricle circulation. Recognizing associations between bodyweight and Fontan pathophysiology may help to define patient-centered exercise and diet interventions that minimize patient morbidity and mortality.     

Survival to the age of 52 years in a man with unrepaired tetralogy of Fallot

Tetralogy of Fallot is the most common cyanotic congenital heart defect during infancy. It is composed of a ventricular septal defect, an overriding aorta, obstruction of right ventricular outflow, and right ventricular hypertrophy. Most patients experience cyanosis at birth and die in childhood without surgical intervention. The rate of survival at 40 years without surgical correction is only 3%. We present the case of a man with tetralogy of Fallot who survived until the age of 52 years without surgical intervention.     

Neurodevelopmental outcomes at 2 and 4 years in children with congenital heart disease

Background and Objectives: Children with congenital heart disease (CHD) are at risk for neurodevelopmental (ND) delays. The purpose of this study is to compare the ND testing results of children with CHD at 2 and 4 years of age and determine if rates of ND delays change over time.
Methods: Children with CHD completed the Bayley Scales of Infant Development‐III (BSID‐III) at 2 years of age, and standardized neuropsychological measures at 4 years. Scores were compared with test norms and were classified as: average (within one SD of test mean); at risk (1‐2 SDs from the test mean); and delayed (>2 SD from test mean). Pearson correlations and McNemar’s exact tests were performed to deter‐ mine the relationship between test scores at the two times of assessment.
Results: Sixty‐four patients completed evaluations at 24 ± 3 months of age and 4 years of age. BSID‐III cognitive and fine motor scores were correlated with pre‐ school IQ and fine motor scores, r = .75 to .87, P < .0001. Agreement in score catego‐ ries was 79% for cognitive and 61% for fine motor. More patients had at risk or delayed scores at age 4 vs age 2 (P≤.01).
Conclusion(s): Despite significant correlations between 2‐ and 4‐year‐old test scores, many patients who scored in the average range at age 2 showed deficits at age 4. BSID‐III scores at age 2 may underestimate delays. Therefore, longitudinal ND as‐ sessment is recommended.     

Every heart beat is under neural command: an hypothesis relating to the cardiac rhythm

In the human heart there is a sequential contraction of the systemic veins, systemic venous sinus and the pectinated right atrium, 'the systemic waltz', and sequential contraction of the pulmonary veins, pulmonary venous sinus and pectinated left atrium, 'the pulmonary waltz'. The systemic veins contract earlier than the pulmonary veins creating a 'duet. We hypothesise that this waltz and duet point to a complex extracardiac control of the cardiac rhythm on a beat-to-beat neural basis.     

Outcome of early and late onset Fontan operation in patients with univentricular heart repair

ObjectiveTo evaluate our experience in the Fontan procedure comparing those below and above 6 years of age.MethodsA review of our clinical database was conducted to identify the patients who received extracardiac Fontan between 2002 and 2010. All demographic, echocardiographic, surgical, haemodynamic and follow-up data were collected. The overall mortality was defined as death occurring from the time of surgery to the most recent follow-up. Early postoperative death was defined as death occurring during admission or within 30 days from the operation. Seventy-six patients with functionally univentricular hearts were included in the study. Patients were divided into two groups. Group A included patients who had received extracardiac Fontan at the age of 6 years or less, whereas group B included patients who had received extracardiac Fontan at an age of more than 6 years.ResultsThe overall hospital mortality was 7.9% (10.2% in group A and 5.9% in group B). No statistically significant difference was seen between the two groups regarding the postoperative mortality including thrombosis, stroke, chylothorax, bleeding, pericardial effusion, wound infection, serious postoperative arrhythmias and protein losing enteropathy. On the other hand the mechanical ventilation duration, duration of hospital and ICU stay, duration of the chest tubes and the postoperative saturation was not significant between the two groups.ConclusionsThe age of the patient at the time of Fontan surgery does not affect the results, in terms of both morbidity and mortality.     

Late Occurrence of Adenosine-Sensitive Focal Junctional Tachycardia in Complex Congenital Heart Disease

Background: Although supraventricular tachycardia in complex congenital heart disease (CHD) has been reported after surgical repair, its exact electrophysiologic identification has been limited to intraatrial reentrant tachycardia (IART). Moreover, junctional tachycardia (JT) has not previously been described as a cause of late postoperative arrhythmia.Methods and Results: Since 1993, a total of 12 patients with congenital heart disease presented with paroxysmal focal JT. The patients with only typical immediate postoperative junctional ectopic tachycardia were excluded. Medical records, standard electrocardiography and Holter monitoring were reviewed. An intracardiac electrophysiologic (EP) study was performed in 11 patients. Ten patients were in post-Fontan status (5.7% of total Fontan survivors). Focal JT occurred more frequently in heterotaxy syndrome among the Fontan survivors (7/52 vs. 3/124; P < 0.05). The commonest anatomy of the atrioventricular (AV) junction was complete AV canal in 8 patients. EP characteristics of focal JT were as follows: (1) various tachycardia mechanisms were identified (increased automaticity or a triggered mechanism in 6/11, and focal reentry in 5/11, including one concealed nodofascicular pathway) (2) ventriculoatrial conduction during tachycardia was either dissociation (7/12) or variable (5/12) (3) All JTs were terminated by adenosine. Class III antiarrhythmic agent was effective in 5/6. His bundle ablation was performed in one Fontan patient, who already had pacemaker because of accompanying intractable IART and sinus node dysfunction.Conclusion: Focal JT may be a source of late term supraventricular tachycardia in patients with complex CHD. The tachycardia mechanism was either automatic/triggered or reentrant. In all patients, JT was effectively terminated by adenosine.