Idebenone and reduced cardiac hypertrophy in Friedreich's ataxia.

BACKGROUND: Friedreich's ataxia encodes a protein of unknown function, frataxin. The loss of frataxin is caused by a large GAA trinucleotide expansion in the first intron of the gene, resulting in deficiency of a Krebs cycle enzyme, aconitase, and of three mitochondrial respiratory chain complexes (I-III). This causes oxidative stress. Idebenone, a short chain quinone acting as an antioxidant, has been shown to protect heart muscle against oxidative stress in some patients. OBJECTIVE: To assess the efficiency of idebenone on cardiac hypertrophy in Friedreich's ataxia. DESIGN: Prospective, open trial. SETTING: Tertiary care centre. METHODS: Idebenone (5 mg/kg/day) was given orally to 38 patients with Friedreich's ataxia aged 4-22 years (20 males, 18 females). Cardiac ultrasound indices were recorded before and after idebenone treatment. RESULTS: After six months, cardiac ultrasound indicated a reduction in left ventricular mass of more than 20% in about half the patients (p < 0.001). The shortening fraction was initially reduced in six of the 38 patients (by between 11-26%) and it improved in five of these. In one patient, the shortening fraction only responded to 10 mg/kg/day of idebenone. No correlation was found between responsiveness to idebenone and age, sex, initial ultrasound indices, or the number of GAA repeats in the frataxin gene. CONCLUSIONS: Idebenone is effective at controlling cardiac hypertrophy in Friedreich's ataxia. As the drug has no serious side effects, there is a good case for giving it continuously in a dose of 5-10 mg/kg/day in patients with Friedreich's ataxia at the onset of hypertrophic cardiomyopathy.

Transcatheter implantation of a bovine valve in pulmonary position: a lamb study.

BACKGROUND: Pulmonary regurgitation can lead to severe right ventricular dysfunction, which is a delicate postoperative problem in the long-term follow-up of patients who had surgery for congenital heart diseases. Clinical conditions of patients suffering from pulmonary valve incompetence are improved by valve replacement with a prosthetic valve. To date, the surgical approach is the only option to replace a pulmonary valve. We report the first experience of percutaneous pulmonary valve implantation. METHODS AND RESULTS: A fresh bovine jugular vein containing a native valve was sutured into a vascular stent and then cross-linked with a 0.6% glutaraldehyde solution for 36 hours. After being hand-crimped onto a balloon catheter, the device was inserted percutaneously according to standard stent-placing techniques. The valved stent was finally deployed in the position of the native pulmonary valve of the lamb. Hemodynamic evaluation was carried out before and 2 months after implantation. Anatomic evaluation was finally performed. Percutaneous pulmonary valve replacement was successful in 5 lambs. No complications were noted. Early and late angiographic and hemodynamic studies confirmed a good position of the stents with a competent valve at the end of the protocol. One stent was slightly stenotic, with macroscopically visible calcifications. CONCLUSIONS: Nonsurgical implantation of pulmonary valves is possible in the lamb. This new technique is similar to standard stent implantation. Thus, it should be feasible in humans, in whom it will lead to a significant reduction of reoperations in patients in need of pulmonary valve replacement.

[Percutaneous closure of patent ductus arteriosus with the Amplatzer duct occluder]. / Fermeture percutanée du canal artériel par la prothèse occlusive Amplatzer.

BACKGROUND AND METHODS: Percutaneous closure of a moderate-to-large sized patent ductus arteriosus using multiple coils or a Rashkind double-umbrella may be technically demanding and raises a significant rate of embolization and residual shunting. This is why we tried a new self-expandable device called Amplatzer Duct Occluder to close transvenously large ductuses in eighteen patients at a median age of 2.8 years (range: 0.7 to 34). They had a patent ductus arteriosus with a minimal diameter > 3 mm (mean: 5 +/- 2 mm). The device had a mean diameter of 9 +/- 2 mm and was delivered through a 6F venous sheath. Aortography was done 5 to 10 minutes after the release and follow-up evaluation was performed with color Doppler echocardiography within 24 h, 1 and 3 to 6 months after the procedure. RESULTS: Placement was successful in all but the first patient (95%). Complete closure was achieved immediately in 4/17 patients (24%) and in 13/17 (76%) 24 h later. Two patients were lost for follow-up. Complete closure was confirmed in 14 of the 15 (93%) reviewed patients at 1 and 3 months. In all patients with a ductal diameter < or = 7.5 mm the closure was complete at 1 month. Embolization occurred in one patient with a 9.7 mm duct and surgery was undertaken. A mild and transient hematuria was observed in one patient. No pulmonary artery stenosis nor aortic obstruction were observed on follow-up. CONCLUSION: The Amplatzer Duct Occluder device offers a safe and effective option to treat patients with a ductus arteriosus which minimal diameter is up to 7.5 mm.

[Mitral subvalvular aneurysm: report of 3 cases]. / Aneurisma subvalvar mitral: a propósito de três casos.

Mitral annular subvalvar Aneurysms are a very uncommon pathology and almost restricted to Blacks Africans. The authors present three cases, describing their clinical presentation, evolution and complications. The complementary exams are also presented and their relevance in the diagnosis is discussed.

[Mitral subvalvular aneurysm]. / Aneurismas subvalvares mitrais.

Mitral subvalvar aneurysms are a rare clinical entity and not commonly described in the literature. They are almost exclusive of the black population in the subsaharian Africa. The authors, in a bibliographic revision, present the different etiological theories, the pathology, the pathophysiology, the clinical presentation and discuss the relative value of the different diagnostic tools. The differential diagnosis is also discussed and the more recent methods of medical and surgical treatment presented.