The clinical case describes a 13-year-old boy with a history of transposition of the great arteries, ventricular septal defect, and pulmonary stenosis who underwent surgical correction at age 1 with the REV procedure and the Lecompte maneuver. At age 2, severe subaortic obstruction required reoperation for subaortic tunnel reconstruction, myectomy, and reimplantation. Due to severe right ventricular outflow tract dysfunction, a 19 mm No-React Injectable BioPulmonic prosthesis was implanted. At 12 years, the patient presented with reduced exercise tolerance. Echocardiography and cardiac catheterisation demonstrated severe stenosis and regurgitation of the pulmonary bioprosthesis, right ventricular dilatation and hypertrophy, and an increased right ventricular–pulmonary artery gradient with normal pulmonary artery pressures. The manuscript presents an in vitro test demonstrating that the No-React Injectable BioPulmonic prosthesis frame can be modified using high-pressure balloons to increase its true inner diameter. The patient subsequently underwent transcatheter valve-in-valve implantation of a 23 mm Sapien 3 following pre-dilation and frame modification of the 19 mm No-React Injectable BioPulmonic prosthesis with a 22 × 20 mm Atlas Gold balloon, achieving an favourable haemodynamic outcome. Post-implant pulmonary arteriography excluded any intra-perivalvular regurgitation. Post-procedure haemodynamic assessment showed a residual peak-to-peak gradient of 10 mmHg, with systolic right ventricular pressures below half of systemic pressure. At the 6-month follow-up after the procedure, the post-procedural peak echocardiographic gradient across the pulmonary prosthesis was measured at 28 mmHg, with no evidence of regurgitation. Short-term results have been optimal, which encourages the use of this strategy for the treatment of similar cases.

Balloon dilatation of coarctation of aorta is a standard of care for the patients presenting with severe left ventricular dysfunction. It can be performed through femoral, carotid, and axillary arterial access. Very few case series were available in the literature through axillary arterial access, despite being its advantage as non-end artery and easily palpable in coarctation of aorta. We present our experience with five cases of neonatal coarctation of aorta with severe left ventricular dysfunction where successful balloon dilatation of coarctation of aorta was performed via axillary approach without adverse events.

Coarctation of the aorta is associated with increased risk for hypertension in adulthood, despite successful repair. The intrinsic mechanisms underscoring hypertension and left ventricular performance in these patients, however, remains to be determined. Our objective was to evaluate left ventricular performance by means of echocardiographic and biochemical parameters at midterm follow-up in normotensive children who have had undergone successful surgical or catheter interventional treatment of coarctation with a residual gradient of less than 20 mmHg at rest. We studied prospectively 14 patients with native aortic coarctation who underwent surgery or balloon angioplasty, the cohort made up of equal numbers of boys and girls, and having a mean age of 8.5 plus or minus 4 years. We also studied 30 age-matched healthy subjects, measuring mitral inflow pulsed wave signals, isovolumic relaxation and contraction times, myocardial performance index parameters, and levels of B-type natriuretic peptide and endothelin-1 in both groups. We found no differences in systolic blood pressure at rest between the patients and their controls. The ventricular septal diastolic dimensions, left ventricular posterior wall dimensions, mitral valve E wave, deceleration time, isovolumic relaxation time, isovolumic contraction time and myocardial performance index were all significantly increased in the patients. Levels of plasma B-type natriuretic peptide and endothelin-1 were also significantly higher in the patients when compared to the control group. We conclude that aortic coarctation is a chronic disease characterized by persistency of myocardial and vascular alterations. The elevated levels of plasma b-type natriuretic peptide and endothelin-1 may be indicative of late onset hypertension after successful treatment of native coarctation in early childhood.

Balloon dilation was attempted in seven symptomatic patients with congenital mitral stenosis aged 7.6±5.3 years. Of the five patients with typical mitral stenosis, four underwent successful dilation with decrease of the mean left atrial pressure and the gradient across the mitral valve and increases in the area of the valve of 127±43 and 85±16%, respectively, as demonstrated hemodynamically or by Doppler echocardiography. In the patient in whom the procedure was unsuccessful, a small child with recurrent pulmonary edema, death occurred during the procedure as a consequence of vasovagal reaction. In the other two patients, one with a parachute-like mitral valve and the other with Shone's syndrome, severe pulmonary hypertension and reversal of the shunt through a patent arterial duct, it was not possible to dilate the valve. In the patient with Shone's syndrome, nonetheless, palliation was achieved by balloon angioplasty of the aortic coarctation and by creation of an atrial septal defect. The patients undergoing dilation remained symptom-free during follow-up and mantained the increase in valvar area as judged by Doppler studies and, in one patient, also by cardiac catheterization. A residual atrial septal defect closed spontaneously in three patients. We conclude that balloon dilation of congenital mitral stenosis is an effective alternative to surgery in patients with typical mitral stenosis. Cross-sectional echocardiography plays an important role in defining valvar morphology and selection of patients. The procedure is not without risk, especially in very sick patients but satisfactory results are long-lasting.

In 38 children with aortic coarctation between the age of three weeks and 16 years, 44 balloon dilation procedures were attempted. At initial catheterization (n=38), the mean gradient dropped from 49.6±21.2 mm Hg prior to dilation, to 15.3±15.8 mm Hg after the procedure (p>0.05). Twenty-six patients were recatheterized 3–24 months after the initial procedure. The mean gradient remained low at 12.7±15.2 mm Hg (range 0–64). Six of the 26 (23%) patients required a second dilation because of significant recoarctation. This proved successful in four, but in two patients, the second dilation failed, and they were referred for elective surgery. Thus, good overall results were obtained in 24 of the 26 (92.3%) patients undergoing reinvestigation following balloon dilation. Complications included requirements for blood transfusion in 9/44 (20%), chest pain during balloon inflation in 3/44 (6.8%), rupture of the balloon in 3/44 (6.8%), and femoral arterial thrombectomy in 3/44 (6.8%). At a mean clinical follow-up of 21 months, 21% of the patients had a weaker femoral pulse on the side used for balloon dilation, while 21% had mild hypertension measured in the arms despite the absence of a significant gradient. One patient (2.6%) developed an aortic aneurysm as a complication of the procedure. We conclude that balloon dilation is a safe and effective procedure in the majority of the patients with native aortic coarctation.

Balloon dilation of the aortic valve was performed in 20 consecutive neonates with critical aortic stenosis using an approach achieved by cutting down on the right carotid artery. The age of the patients ranged from one to 25 days (mean seven days) and their weight from 2.1 to 4.0 kg (mean 3.16 kg). All patients were evaluated before cardiac catheterization with cross-sectional and Doppler echocardiography so as to keep the catheterization procedure as short as possible. Balloon dilation was accomplished in all patients. The only complication was an apical perforation by the guide wire in two cases. The ensuing pericardial effusion was immediately drained with pericardiocentesis and the subsequent course of the procedure was uneventful. Immediate results showed dramatic improvement in cardiovascular conditions. The transvalvar pressure gradient fell from 80±40 to 27±20 mm Hg (p<0.001). Left ventricular ejection fraction evaluated by echocardiography increased from 30±21% before dilation to 54±18% 24-48 hours after the procedure (p<0.001). In all patients, the procedure was free from vascular complications. Aortic regurgitation was documented after the procedure in 11 patients, being severe in one, moderate in five and trivial in five. Seven patients died, although in only one was the death related directly to the procedure itself. Six patients died because of associated lesions despite an immediate satisfactory result of the balloon valvoplasty. The 13 surviving patients are doing well, and are receiving no medications. During a mean follow-up of 25 months (range 2-54 months), four patients have developed restenosis. One underwent surgical valvotomy at one year of age. The second was successfully redilated through the same approach at two months of age. The other two have a significant gradient, as assessed by Doppler measurements (60 and 70 mm Hg), with normal systolic ventricular function. Two patients have moderate aortic regurgitation. Balloon dilation achieved through cutdown on the right carotid artery is a safe and effective alternative to surgery in neonates with isolated aortic stenosis. The unfavorable results are mainly due to associated anomalies.

A two-month-old boy, with complex pulmonary atresia, became increasingly cyanosed 10 days after a modified 5 mm right Blalock-Taussig shunt. There was no shunt flow on auscultation or Doppler echocardiography. Despite anticoagulation with heparin, the shunt remained occluded. After demonstration of the occluded shunt at angiography, a guide wire was easily passed through the occlusion and into the pulmonary artery. Balloon dilation was then successfully accomplished with a 6 mm diameter angioplasty balloon resulting in a patent shunt. The shunt was still widely patent at cardiac catheterization six months later.

Twenty-six patients requiring palliation for the tetralogy of Fallot were treated by balloon dilation. The mean age at dilation was 8.5 months (range 0.5−20.6) and the mean weight 6.7 kg (range 2.6−10.7). Successful dilation was achieved in 25 patients. The mean ratio of the balloon to the diameter of the pulmonary outflow tract was 1.6 (range 1.2−2.0). The aortic oxygen saturation increased from mean±SD of 80±12.4% before to 91±4.3% after dilation (p<0.05). The pulmonary arterial oxygen saturation rose from 64±10.7% to 80±7.7% (p<0.05). Transient hypotension and arterial desaturation were noted in 19 patients during inflation of the balloon. One patient had a cardiac arrest prior to dilation and died afterwards. Seven patients had cyanotic spells related to the procedure. Attempts to cross the pulmonary valve resulted in infundibular perforation by the guide wire in one patient. Of the 24 survivors who initially had successful dilation procedures, three have needed a Blalock-Taussig shunt. Palliation without a shunt was achieved in the remaining 21 patients. In 12 patients, repeat angiography, 2.5−20 months (mean 9.1) after dilation, showed an increase in the diameter of the outflow tract from 7.1±2.1 mm before to 9.5±2.0 mm after dilation (p<0.05). Diameters of the pulmonary arteries increased from 6.3±2.2 mm on the right and 6.8±1.9 mm on the left before to 9.2±2.2 mm and 9.3±2.5 mm respectively after dilation (p<0.05 for both branches). Surgical correction has been achieved in 22 patients, 21 of these 2−22 months after balloon dilation and the other patient 20 months after construction of a shunt. At operation, the leaflets of the pulmonary valve were noted to be torn in five patients. In 12 patients, there was extensive scarring of the infundibulum. Balloon dilation of the right ventricular outflow tract achieves adequate palliation and may result in an increase in the diameter of the pulmonary valve and branches of the pulmonary trunk. It should be considered as an alternative to shunt procedures in children with tetralogy of Fallot.

Fifteen patients requiring palliation for tetralogy of Fallot were treated by balloon dilation because of hypercyanotic spells. The mean age at dilation was 1.9 ± 0.7 years (range 0.5 – 3), and the mean weight 9.8 ± 2.1kg (range 6.0 –13.5). Dilation of the outflow tract was combined with dilation of the left and/or right pulmonary arteries in 5 patients. Successful dilation was achieved in 12 patients (80%), but failed in 3 patients with hypoplastic pulmonary arteries. In one patient, the stenosis of the right pulmonary artery could not be dilated because of a very sharp angle at the site of the stenosis. Two of the 3 patients in whom the procedure failed died of severe cyanotic spells within 24 hours of the unsuccessful procedure. No major complications occurred during or after the procedure in the cases undergoing successful dilation. The arterial oxygen saturation increased significantly, from 71 ± 5.7% to 89 ± 3.9%, immediately after the procedure (p < 0.005). During a period of follow up of 6 ± 3.7 months (range 1 – 13), the procedure was repeated on 3 occasions, and successfully accomplished in 2 of these. In conclusion, balloon dilation is a satisfactory palliative procedure for tetralogy of Fallot in those units in which total correction is not performed under 2 to 3 years of age.

We describe our treatment of a premature baby born weighing 1400 g with severe aortic stenosis, with a gradient of 80 mmHg across the valve. Efforts to advance a 6 mm angioplasty catheter into the stenotic aortic valve via the left ventricle failed. Anterograde angioplasty, instead, was performed using two 4 mm coronary angioplasty catheters. Six months subsequent to the intervention, the pressure gradient measured 25 mmHg, and there was no hemodynamically significant aortic insufficiency.

We describe post azygos obstruction of the superior caval vein following repair of a mixed variety of totally anomalous pulmonary venous connection. Balloon dilation was immediately successful, and has provided persistent relief at a follow-up of 20 months.

Balloon dilation was performed in four patients with postoperative pulmonary stenosis who had undergone surgical creation of a coronary arterial tunnel in the pulmonary trunk. Two patients had complete transposition in whom the arterial switch operation had been performed using the modified Aubert method. The other two patients had anomalous origin of the left coronary artery from the pulmonary trunk treated with the Takeuchi procedure. Balloon dilation was performed at 11 locations. The pressure gradient decreased from 48 ± 22 to 24 ± 14mmHg (p<0.01), and the diameter of the narrowest segment increased from 5.3 ± 2.5 to 7.5 ± 2.8mm (p<0.01), respectively. Of the 11 procedures, 8 (73%) were judged successful with use of the criterion of success as a greater than 50% decrease in pressure gradient, and/or a greater than 50% increase in diameter. The inflated balloon must have compressed the coronary arterial tunnel in the pulmonary trunk, but there was no apparent myocardial damage in any patient, although transient and mild ST-T changes appeared on electrocardiographic monitoring during the procedure in 2 patients. Rupture of the wall of the pulmonary trunk occurred in two patients, one of whom required elective surgical intervention. These data suggest that balloon dilation should be performed with caution for management of postoperative pulmonary arterial stenosis in patients with a surgically created intrapulmonary coronary arterial tunnel, since tearing the wall of the pulmonary trunk may occur.

We successfully performed percutaneous transluminal angioplasty to treat severe renovascular hypertension with left ventricular failure in a 5-month-old infant. Using the transcarotid approach, we dilated the stenotic left renal artery without any difficulties, using progressively larger balloons designed for dilation of coronary arteries.