Transcatheter treatment of pulmonary outflow tract obstruction: a review

Transcatheter Interventions in Adult Congenital Heart Disease

This article provides a detailed review of the current practices and future directions of transcatheter interventions in adults with congenital heart disease. This includes indications for intervention, risks, and potential complications, as well as a review of available devices and their performance.

The Journey of an Indian Pediatric Cardiologist : Dr. K. C. Chaudhuri Lifetime Achievement Award/Oration at AIIMS, New Delhi, September 2017

The life journey of an Indian pediatric cardiologist, who bestowed considerable attention to the development of new knowledge and train/teach physicians around the world while providing care of patients with heart disease over a 45-y period, is reviewed. This appraisal focuses particular attention on the scientific contributions to the literature. These include spontaneous closure of physiologically advantageous ventricular septal defects, various issues related to a congenital heart defect namely, tricuspid atresia and transcatheter and, interventional pediatric cardiac procedures.

Percutaneous balloon valvuloplasty for congenital pulmonary valve stenosis in adults

BACKGROUND

Although pulmonary valvular stenosis is not uncommon in adults, there are few reports of percutaneous pulmonary valvuloplasty in adults, despite the possibility of avoiding heart surgery.

AIM

This report describes the experience in adult patients undergoing this procedure and evaluates its effectiveness and tolerance.

METHODS

Over an 8-year period (1989-1997), pulmonary valvuloplasty was considered in 22 adult patients [8 men, 14 women; mean age 28.0 years +/- standard deviation (SD) 10.3; range 16-46 years] with congenital pulmonary valve stenosis. Sixteen patients were asymptomatic with pulmonary systolic murmurs, although 6 patients presented with dyspnea. Before the procedure, the mean transpulmonary valve gradient was 53.2 +/- 24.8 mmHg SD, with a mean right ventricular systolic pressure of 74.6 +/- 28.4 mmHg SD, and mean pulmonary artery pressure was 21.4 +/- 6.4/10.2 +/-3.9 mmHg.

RESULTS

The procedure was successful in 19 patients (6 men, 13 women) and was well tolerated and free of complications. Following the procedure, the mean transvalvular gradient was 15.5 +/- 11.5 mmHg, with a mean right ventricular systolic pressure of 40.5 +/- 13.6 mmHg and a mean pulmonary systolic pressure of 24.3 +/- 7.4 mmHg. This represented mean fall in transpulmonary valve gradient of 42.4 +/- 22.0 mmHg (paired t-test, p < 0.0001). After a mean follow-up of 20.1 months (13.4 SD), most patients remained well and asymptomatic, although two patients required repeat valvuloplasty.

CONCLUSION

Pulmonary valvuloplasty is a well tolerated and effective treatment for pulmonary valve stenosis in adults, with few complications and no need for surgery. This procedure should be considered as the primary treatment of adult patients with pulmonary valve stenosis.

Excimer laser ablation for valvular angioplasty in pulmonary atresia and intact ventricular septum

BACKGROUND AND OBJECTIVES

The prognosis for infants with pulmonary atresia and intact ventricular septum (PA/IVS) is poor and they present a major management challenge. Mechanical penetration of the atretic pulmonary valve is an applicable option for decompression of the right ventricle and optimization of left ventricular function. The utilization of laser energy for debulking and vaporization of the atretic valve tissue is a relevant approach due to the potential for controlled, precise mode of energy distribution.

STUDY DESIGN/PATIENTS AND METHODS

A 4-month-old female with PA/IVS whose failure to thrive was accompanied by critical hemodynamic abnormalities received successful percutaneous pulmonary valve plate ablation by a 0.9 mm pulsed-wave ultraviolet excimer laser catheter (308 nm wavelength, fluence 50 mJ/mm(2); 30 Hz). A "step-by-step" lasing technique was applied whereby the tip of the emitting laser catheter is advanced ahead of a guide wire that serves mainly as support for positioning of that catheter.

RESULTS

Adequate penetration of the atretic tissue enabled introduction of balloon dilations resulting in patency of the atretic valve, decompression of the right ventricle, improved right and left ventricular hemodynamics, and oxygenation. To further investigate the effect of excimer laser energy on atretic valvular tissue this laser was applied in a specimen of heart from an infant who died because of PA/IVS. Histopathologic examination of the irradiated tissue revealed no laser-induced injury to the pulmonary valve.

CONCLUSIONS

Thus, laser ablation and penetration of an atretic pulmonary valve is feasible and safe. The penetration of the atretic valve with the laser catheter enables subsequent introduction of various sizes balloon dilations. The application of available laser sources for treatment of congenital heart diseases is reviewed.

Recent advances in pediatric cardiology--electrophysiology, transcatheter and surgical advances

Whereas the medical advances were reviewed in the previous paper, electrophysiological, transcatheter and surgical advances will be the focus in this review. Greater understanding of the arrhythmias, development of non-pharmacological treatment, namely catheter ablation and internal cardioverter-defibrillator (ICD) and miniaturization pacemakers and IDs have occurred in the last decade so that the methods could be applied to smaller and more complex patient population. Surgery has been the traditional treatment option for palliation and correction of congenital and acquired heart defects in infants and children. During the last one to one and one-half decades, a remarkable number of transcatheter methods were developed and refined. These developments during the last decade were reviewed and include long-term results of balloon dilatation procedures, transcatheter closure of atrial septal defects, patent ductus arteriosus, and ventricular septal defect, percutaneous valve replacement, intravascular stents to manage vascular obstructive lesions that can not be satisfactorily balloon-dilated, catheter completion of Fontan procedure, myocardial reduction in hypertrophic cardiomyopathy and other miscellaneous procedures. Recent advances in the transcatheter modes of therapy have added a new dimension to the management of neonates, infants and children with heart disease. They should now be added to the armamentarium available to the Pediatrician and Pediatric Cardiologist in the management of cardiac problems in the pediatric patient. Surgical methods and concepts have been greatly refined such that surgery can be undertaken even in the sickest and most complex patient. The majority of congenital heart defects can be corrected by open heart surgery; some require prior palliation and others can be operated without prior palliation. Recent advances in various defects were reviewed.

Long-term follow-up results after balloon dilatation of pulmonic stenosis, aortic stenosis, and coarctation of the aorta: a review

Although immediate and intermediate-term results after balloon dilatation of congenital stenotic lesions of the heart in children are well studied, long-term results have not been documented. Therefore, we reviewed our experience along with the limited published data to address this issue. Late follow-up after balloon pulmonary and aortic valvuloplasty shows low-residual gradients, reintervention-free rates in the mid-80s for pulmonic and in the mid-50s for aortic stenosis, and an increase in degree and prevalence of similunar valve insufficiency. Balloon angioplasty of aortic coarctation results in low-residual gradients, residual hypertension in a minority of patients, low prevalence of aneurysms, and high rates of recurrence in the neonate and young infant. Overall, balloon dilatation is a useful technique in relieving congenital obstructive lesions of the heart in the pediatric patient, but continued study of (1) late pulmonary and aortic insufficiency after valvuloplasty, (2) recurrence and aneurysms after balloon angioplasty of coarctations and, (3) femoral artery compromise in lesions requiring transfemoral artery approach is warranted.

Results of three to 10 year follow up of balloon dilatation of the pulmonary valve

BACKGROUND

The results of immediate and short term follow up of balloon dilatation of the pulmonary valve have been well documented, but there is limited information on long term follow up.

OBJECTIVE

To evaluate the results of three to 10 year follow up of balloon dilatation of the pulmonary valve in children and adolescents.

SETTING

Tertiary care centre/university hospital.

DESIGN

Retrospective study.

METHODS AND RESULTS

85 patients (aged between 1 day and 20 years, mean (SD) 7.0 (6.4) years) underwent balloon dilatation of the pulmonary valve during an 11 year period ending August 1994. There was a resultant reduction in the peak to peak gradient from 87 (38) to 26 (22) mm Hg. Immediate surgical intervention was not required. Residual gradients of 29 (17) mm Hg were measured by catheterisation (n = 47) and echo Doppler (n = 82) at intermediate term follow up (two years). When individual results were scrutinised, nine of 82 patients had restenosis, defined as a peak gradient of 50 mm Hg or more. Seven of these patients underwent repeat balloon dilatation of the pulmonary valve: peak gradients were reduced from 89 (40) to 38 (20) mm Hg. Clinical evaluation and echo Doppler data of 80 patients showed that residual peak instantaneous Doppler gradients were 17 (15) mm Hg at long term follow up (three to 10 years, median seven), with evidence for late restenosis in one patient (1.3%). Surgical intervention was necessary to relieve fixed infundibular stenosis in three patients and supravalvar pulmonary stenosis in one. Repeat balloon dilatation was performed to relieve restenosis in two patients. Actuarial reintervention free rates at one, two, five, and 10 years were 94%, 89%, 88%, and 84%, respectively. Pulmonary valve regurgitation was noted in 70 of 80 patients at late follow up, but neither right ventricular dilatation nor paradoxical interventricular septal motion developed.

CONCLUSIONS

The results of late follow up of balloon dilatation of the pulmonary valve are excellent. Repeat balloon dilatation was performed in 11% of patients and surgical intervention for subvalvlar or supravalvar stenosis in 5%. Most patients had mild residual pulmonary regurgitation but right ventricular volume overload was not required. Balloon dilatation is the treatment of choice in the management of moderate to severe stenosis of the pulmonary valve. Further follow up studies should be undertaken to evaluate the significance of residual pulmonary regurgitation.