Balloon angioplasty of postoperative aortic recoarctation

Balloon angioplasty for aortic coarctation--report of a questionnaire survey by the Japanese Pediatric Interventional Cardiology Committee

The aim of this study was to analyze the results of a questionnaire survey regarding acute and late effects of balloon angioplasty for aortic coarctation in Japan. Considerable controversy still exists regarding the effectiveness and safety of balloon angioplasty in native coarctation. Moreover, little information about this mode of treatment is available from Japan. A questionnaire was sent to 55 Japanese institutions with pediatric cardiology units. A total of 208 patients from 35 institutions were reported and analyzed for indications for balloon angioplasty, acute and late results, and complications. Balloon angioplasty was performed in 56 patients with native coarctation (group I) and in 152 patients with postoperative recoarctation (group II). In group I, the pressure gradient across the coarcted site decreased significantly from 34 +/- 19 to 16 +/- 21 mmHg (p < 0.001), and the diameter of the coarcted site increased significantly from 3.7 +/- 1.7 to 6.0 +/- 2.5 mm (p < 0.001). In group II the pressure gradient significantly decreased from 41 +/- 20 to 15 +/- 15 mmHg (p < 0.001) and the diameter of the coarcted site significantly increased from 4.2 +/- 2.2 to 6.8 +/- 3.1 mm (p < 0.001). The restenosis rate was significantly higher in group I (19/41, 46%) than in group II (25/139, 18%) (p = 0.0006). Redilation was successfully performed in 27 of 29 of the patients with restenosis. Major complications included femoral pulse loss, transient bradycardia, and arrhythmia. No patient died of a cardiac event related to the procedure. The significant risk factors for late restenosis included type of coarctation, age under 4 months, balloon size used, pressure gradient and coarctation diameter before the procedure. Balloon angioplasty is a suitable treatment for aortic coarctation in both native coarctation and postoperative recoarctation. Restenosis was significant after initial balloon angioplasty in native coarctation but redilation was effective in most cases. The most significant risk group for restenosis is young children with native coarctation.

Dilation mechanism, causes of restenosis and stenting in balloon coarctation angioplasty

This review focuses on the individual dilation mechanism, the possible cause of restenosis after balloon angioplasty and the clinical application of a stent in coarctation of the aorta. Balloon angioplasty is still not the first choice of therapy in neonates with native coarctation because of the potential risk of aortic disruption, the high incidence of restenosis and the satisfactory results of surgical coarctectomy. Intravascular ultrasound imaging provides the individual mechanism of aortic dilation by balloon, and this will be a new modality for assessing the relationship between restenosis and aortic luminal morphology after balloon dilation. Although the cause of restenosis after balloon angioplasty remains uncertain, it may be due to a combination of elastic recoil by ductal tissue constriction, intimal hyperplasia and arterial remodelling. A stent could be an effective alternative to conventional balloon angioplasty in native coarctation of the aorta, preventing ductal tissue constriction. However, the problematic relationship between patient growth and relative stenosis of the stent should be clarified before clinical application of a stent for this disease.