Novel curved balloon catheter for dilating postoperative angled lesions associated with congenital heart disease.

OBJECTIVES: This study aimed to analyze the surface stress generated by a novel curved balloon and assess its efficacy for treating angular lesions associated with congenital heart disease. BACKGROUND: Obstructions at the anastomosis of aortopulmonary shunts and cavopulmonary connections may occur postoperatively. Catheter interventions are often performed for such lesions; however, acute angulation may cause balloon slippage or inappropriate stress on the vessel wall. METHODS: We dilated the curved balloon in a curved vessel model and measured the resultant wall stress and its distribution. Clinical evaluations were performed using this balloon in angled lesions. RESULTS: In the curved vessel model, curved balloons generated uniform stress on the lesser and greater curvatures (curved type, lesser/greater = 0.343 MPa/0.327 MPa; P = 0.61), whereas straight balloons caused disproportionate stress (straight type, lesser/greater = 0.358 MPa/0.254 MPa; P = 0.19). However, the difference in average stress was not statistically significant. Furthermore, the stress was uniform along the entire length of the curved balloon, but differed between the mid and end portions of the straight balloon. Curved balloon dilations were performed for 10 lesions in 7 patients. The curved balloon conformed well to the angulated lesion without slipping. The median percent change in the minimal lumen diameter (MLD) was 64% (range, 0-206%). In 5 lesions, MLD increased by ≥50%. Oxygen saturation increased by 5% (0-9%). CONCLUSIONS: Although further clinical evaluation is necessary, this novel curved balloon may be a reasonable alternative in angled lesions, providing better conformability and preventing excessive stress to the vessel wall adjacent to the stenosis.

Reliability of a rapid test for the clinical diagnosis of influenza A/H1N1 2009.

BACKGROUND: The rapid diagnosis of a pandemic influenza A/H1N1 2009 (H1N1pdm) virus infection is required in ambulatory care settings, since early identification can prevent further transmission. However, the sensitivity of rapid influenza diagnostic tests (RIDTs) is still questionable, and specific indicators for H1N1pdm and/or false-negative results by RIDTs have not been clearly determined. METHODS: From June to December 2009, nasal swabs from 324 patients at Kochi Health Science Center were used for the diagnosis of infection by RIDT and reverse transcription polymerase chain reaction. RESULTS: The sensitivity of the RIDT was determined to be 80.0% and the specificity 97.1%. Multivariate analysis revealed that the frequencies of contagiousness and headache were significant in patients with H1N1pdm infection, in addition to common symptoms of respiratory infection. These data indicated that the H1N1pdm virus had high infectivity and was harmful to the endocranial environment. In the false-negative group, the time interval between onset and consultation was 5.5 ± 6.5 h (median ± interquartile range), which was significantly shorter than the 11.5 ± 7.0 h in the true-positive group. The sensitivity of the RIDT was significantly low during the time-period within 3 h from onset (56.0%); however after 4 h the sensitivity was determined to be >80%. These data indicated that the concentration of the virus in nasal swabs was elevated over the course of the disease. CONCLUSIONS: We have demonstrated that the RIDT is reliable for the diagnosis of H1N1pdm infection. Taking into consideration the time interval between onset and consultation and other features of H1N1pdm, such as contagiousness and headache, it may be necessary to re-test RIDT-negative cases later.