How can something so small cause so much grief? Some thoughts about the underdeveloped right ventricle in pulmonary atresia and intact ventricular septum

Congenital coronary artery anomalies: a bridge from embryology to anatomy and pathophysiology--a position statement of the development, anatomy, and pathology ESC Working Group

Congenital coronary artery anomalies are of major significance in clinical cardiology and cardiac surgery due to their association with myocardial ischaemia and sudden death. Such anomalies are detectable by imaging modalities and, according to various definitions, their prevalence ranges from 0.21 to 5.79%. This consensus document from the Development, Anatomy and Pathology Working Group of the European Society of Cardiology aims to provide: (i) a definition of normality that refers to essential anatomical and embryological features of coronary vessels, based on the integrated analysis of studies of normal and abnormal coronary embryogenesis and pathophysiology; (ii) an animal model-based systematic survey of the molecular and cellular mechanisms that regulate coronary blood vessel development; (iii) an organization of the wide spectrum of coronary artery anomalies, according to a comprehensive anatomical and embryological classification scheme; (iv) current knowledge of the pathophysiological mechanisms underlying symptoms and signs of coronary artery anomalies, with diagnostic and therapeutic implications. This document identifies the mosaic-like embryonic development of the coronary vascular system, as coronary cell types differentiate from multiple cell sources through an intricate network of molecular signals and haemodynamic cues, as the necessary framework for understanding the complex spectrum of coronary artery anomalies observed in human patients.

Pulmonary balloon valvuloplasty in a fetus with critical pulmonary stenosis/atresia with intact ventricular septum and heart failure

Outcome of fetuses with critical pulmonary stenosis (critical PS) or atresia of the pulmonary valve (PA) with intact ventricular septum (IVS) is closely related with right ventricle hypoplasia and its consequent hemodynamics. Fetal echocardiography not only allows early detection of this condition but also monitors its normally unfavorable evolution. These cases may benefit from intrauterine intervention relieving outflow tract obstruction in order to achieve a biventricular circulation. Successful valvuloplasty of the pulmonary valve was performed in a fetus with critical PS-IVS and heart failure at 25 weeks. After the procedure there was a significant improvement in fetal hemodynamics. Follow-up scans at 34 weeks detected a significant restenosis with signs of circulatory failure leading to premature delivery of the baby. An immediate postnatal valvuloplasty successfully completed the ultimate objective of biventricular repair. Fetal pulmonary valvuloplasty is feasible and may change the natural history of the disease in fetuses with critical PS-IVS.

Pulmonary atresia with intact ventricular septum: management of, and outcomes for, a cohort of 210 consecutive patients

OBJECTIVES

We sought to determine trends, and outcomes, for a cohort of patients with pulmonary atresia with intact ventricular septum born between 1965 and 1998.

BACKGROUND

Pulmonary atresia with intact ventricular septum is a complex lesion that remains a therapeutic challenge, particularly regarding the suitability for biventricular repair.

METHODS

We identified 210 consecutive patients, and reviewed their medical records, initial angiograms, and echocardiograms, along with the relevant surgical and pathology reports.

RESULTS

The mean initial Z-score for the diameter of the tricuspid valve was -0.99 +/- 1.95, with Ebstein's malformation in 8%. A right ventricular dependent coronary arterial circulation was found in 23%. The proportion of patients who received treatment increased over time, although placement of an arterial shunt was the predominant initial procedure throughout the experience. At the last follow-up, 107 patients had not reached the planned final stage of their repair, and 79% of these had died. Of the 103 reaching the final stage of planned repair, 58 had undergone attempted biventricular repair, with 34% dying; 14 had undergone attempted one and a half ventricular repair, with 7% dying, and 31 had undergone attempted functionally univentricular repair, with 10% dying. Overall, survival was 57% at the age of 1 year, 48% at 5 years, and 43% at 10 years. Survival improved over time, with survival of 75% at 1 year, and 67% at 5 years, for patients born between 1992 and 1998. An earlier date of birth, the presence of Ebstein's malformation, and prematurity were all significant independent factors associated with decreased survival. A greater severity of coronary arterial abnormalities was significantly associated with a greater likelihood of left ventricular dysfunction during follow-up.

CONCLUSIONS

The outcomes for patients born with pulmonary atresia with intact ventricular septum have improved over time, albeit that careful initial management, and better selection, is still indicated for those planned to undergo biventricular repair.

A most peculiar coronary circulation in a patient with pulmonary atresia and intact ventricular septum

A patient with pulmonary atresia and intact ventricular septum was found to have a right ventricular-dependent coronary circulation. In this infant both coronary arteries lacked their normal proximal connection with the aorta, perhaps the most egregious form of this prejudicial coronary circulation. Even more interesting was a direct collateral vessel originating from the descending thoracic aorta and connecting with the coronary circulation. This patient has undergone bilateral modified Blalock-Taussig shunts, and left ventricular function seems preserved.

Transcatheter perforation of the right ventricular outflow tract as initial therapy for pulmonary valve atresia and intact ventricular septum in the newborn

The clinical impact of transcatheter perforation and dilatation of the right ventricular outflow tract in neonates with pulmonary atresia and intact ventricular septum was reviewed. Between April 1992 and December 1994, 8 neonates underwent transcatheter perforation of the right ventricular outflow tract. Radiofrequency energy was employed in 6 patients and wire perforation in 2 patients. Mean patient age at intervention was 1.9 +/- 0.6 days and weight 3.4 +/- 0.5 kg. Median tricuspid valve annulus was 10.9 mm (range: 4.0-13.0 mm) and Z-value -0.85 (range: -4.5-1.0). The mean right ventricular systolic pressure fell from 117 +/- 16 to 55 +/- 15 mm Hg (P < 0.0001), and the right ventricular to aortic pressure ratio decreased from 1.81 +/- 0.33 to 0.82 +/- 0.28 (P < 0.0001). The arterial duct was patent in all. No acute complications occurred. Aortopulmonary shunts were performed in 7 patients at a median 6 days (range: 3-23 days) following catheterization. One patient developed sepsis and died after surgical resection of infected tissue, while a second patient died of a blocked aortopulmonary shunt 17 months following discharge. Median follow-up for the 6 surviving patients was 8 months (range: 4-32 months). One patient has achieved and a second is awaiting biventricular repair. Transcatheter perforation appears to be a promising form of therapy in selected patients with pulmonary atresia, and potentially facilitates algorithms leading to a biventricular repair.

A one-way valved atrial septal patch: a new surgical technique and its clinical application

Patients who undergo surgical repair of congenital heart defects, characterized by a hypoplastic right ventricle or high pulmonary vascular resistance, are at high risk for the development of postoperative right heart failure. This risk may discourage the surgical team from carrying out a biventricular or complete repair in such patients. To reduce the risk for right heart failure, we developed a one-way, valved, atrial septal patch to serve as an artificial one-way foramen ovale and tested it in an animal model. By permitting right-to-left shunt, this device decompresses the failing right ventricle and maintains systemic cardiac output. The device has been used in 15 patients divided into three different groups: group 1 (n = 8), patients with a hypoplastic right ventricle and pulmonic stenosis or atresia, seven of whom underwent a biventricular repair; group 2 (n = 5), patients with evidence of pulmonary disease after longstanding left-to-right shunt caused by a correctable atrial or ventricular septal defect, all of whom had a complete repair; group 3, two patients with acute right heart failure in whom the device was used as a last option of treatment to wean them from cardiopulmonary bypass. This article presents our data in regard to the use of the one-way, valved, atrial septal patch and the indications for its clinical use.

Morphologic and hemodynamic consequences after percutaneous balloon valvotomy for neonatal pulmonary stenosis: medium-term follow-up

OBJECTIVES

This study sought to evaluate ventricular and valvular morphologic changes, hemodynamic consequences and clinical outcomes of pulmonary balloon valvotomy performed in the neonatal period.

BACKGROUND

Previous studies support percutaneous balloon valvotomy as the management option of choice for infants and children with valvular pulmonary stenosis. Less information is available to define the impact of valvotomy on the clinical course when performed in the neonatal period.

METHODS

Patient records, catheterization data, cineangiograms and selected echocardiograms (initial and most recent studies) of 37 consecutive neonates undergoing attempted balloon dilation were reviewed.

RESULTS

Dilation was accomplished in 35 (94%) of 37 attempts. Immediately after dilation, the transvalvular peak to peak systolic gradient decreased from 60 +/- 22 mm Hg (mean +/- SD, range 20 to 100) to 11 +/- 10 mm Hg (range 0 to 45) (p < 0.0001), and the right ventricular/aortic systolic pressure ratio decreased from 1.25 +/- 0.43 (range 0.5 to 2.6) to 0.66 +/- 0.22 (range 0.2 to 1) (p < 0.0001). Oxygen saturation measured by percutaneous oximetry increased from 80 +/- 7% to 92 +/- 4% (p < 0.0001). Three patients died (8%), and two required repeat balloon dilation. At the follow-up visit (median 31 months, range 6 months to 8 years), the estimated peak instantaneous Doppler gradient was 15 +/- 9 mm Hg (range 6 to 36). Thickening of valve leaflets, initially present in 93% of patients, was found in only 4%, and leaflet mobility improved in all. Hypoplasia of the right ventricle, initially present in 31%, was found in only 4% at the latest evaluation. Pulmonary annulus diameter Z score increased from -3 +/- 1.0 to 0 +/- 0.1 (p < 0.0001). Freedom from reintervention was 90%, 84% and 84% at 1, 2 and 8 years, respectively.

CONCLUSIONS

These data support the application of balloon valvotomy as the initial intervention in the treatment algorithm for neonates with critical pulmonary valve stenosis. Medium-term follow-up observations demonstrate sustained hemodynamic relief and support maturation of the right ventricle and pulmonary valve annulus, with the expectation of a good long-term outcome.