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1.
Balloon angioplasty was performed in 46 patients (age 2-40 yr) with discrete native coarctation of aorta. Patients with associated patent ductus arteriosus, aberrant subclavian artery and aneurysms were excluded. The peak systolic gradient across the coarcted segment decreased from 52.1 +/- 18.5 mmHg to 18.6 +/- 14.8 mmHg (p less than 0.001), and the diameter of the coarcted segment increased from 3.6 +/- 1.7 mm/m2 to 9.1 +/- 3.2 mm/m2 (p less than 0.001). Follow-up haemodynamic and angiographic studies performed in 21 patients at 13.1 +/- 6.9 months after angioplasty, showed good results in 15 patients. Four patients undergoing haemodynamic study and 4 other patients undergoing noninvasive evaluation were graded as having bad results at follow-up. In 5 of these patients the poor results were due to primary failure of angioplasty in relieving the gradient, and three developed re-coarctation after initial fall in the trans-coarctation gradient. Four risk factors were identified on univariate analysis, which were associated with significantly larger residual gradients at follow-up: (1) size of isthmus/size of coarcted segment ratio less than 3.0; (2) size of post-coarctation descending aorta/size of isthmus ratio greater than 1.75; (3) size of coarcted segment after angioplasty/size of coarcted segment before angioplasty ratio less than 2.0; and (4) size of balloon/size of coarcted segment ratio less than 3.0. The presence of one or more risk factors was associated with bad late results. On multivariate analysis the ratio of balloon size/coarcted segment size was found to be the sole independent predictor of the late outcome (p less than 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
2.
An attempt was made to correlate the NYHA Functional class with the hemodynamic status of 196 patients at an average of 21.2 months following the intracardiac repair of tetralogy of Fallot. 171 patients were in Functional class I (87.2%), 9 in class III (4.5%), 5 in class II (2.5%) and 11 in class IV (5.6%). Right and left heart catheterisation and cardiac angiography revealed the hemodynamic status of these patients to be excellent in 92 (46.4%), good in 37 (18.8%), satisfactory in 6 (3.0%) and unsatisfactory in 61 (31.6%). Whereas all patients in Functional class II, III and IV had unsatisfactory hemodynamic findings, patients in Functional Class I were hemodynamically heterogeneous and included excellent (53.8%), good (21.6%), satisfactory (3.5%) and unsatisfactory (21%) groups. The surgical technique did not seem to determine the functional status. While early reoperation is advisable for patients with functional disability, caution is necessary in considering reoperation for patients in Functional class I who have hemodynamic findings which are classified as unsatisfactory.  相似文献   
3.
A rare combination of tetralogy of Fallot, absent pulmonary valve and absent left pulmonary artery is described. The clinical and angiographic profile and the impact on management are discussed. The embryology is outlined.  相似文献   
4.
A 72-year-old hypertensive man with diabetes had a previously undiagnosed pattern of coronary artery distribution: the ramus intermedius from the left sinus, and the separate origin of the left anterior descending artery, left circumflex artery and right coronary artery from the right sinus. A unique form of branching, a hybrid distribution, was also noted: the left anterior descending artery giving off a right ventricular branch and septals arising from the ramus. No intervention was planned due to the minimal disease observed with angiography and the absence of an interarterial course.  相似文献   
5.
BACKGROUND: There is a paucity of data regarding the long-term outcome of patients operated for ventricular septal defect with severe pulmonary arterial hypertension and elevated pulmonary vascular resistance. METHODS AND RESULTS: We evaluated the long-term follow-up results of a selected cohort of patients with nonrestrictive ventricular septal defect and elevated pulmonary vascular resistance (>6 Wood units). Thirty-eight patients, median age 7.5 years (range 6 months-27 years), with nonrestrictive ventricular septal defect with severe pulmonary hypertension were operated between 1985 and 1996 at our institute. Preoperative pulmonary vascular resistance, ratio of pulmonary blood flow to systemic blood flow, and ratio of pulmonary vascular resistance to systemic vascular resistance were 7.63+/-1.8 Wood units, 1.9+/-0.48, and 0.41+/-0.12, respectively. The majority (68.4%) had perimembranous ventricular septal defect. Thirty patients (79%) had a good outcome and were asymptomatic at a mean follow-up of 8.7 years, with significant reduction in pulmonary artery pressures. Eight patients (21%) had a poor outcome, which included 5 immediate postoperative deaths, 1 late death and 2 surviving patients with persistent severe pulmonary arterial hypertension. There was no significant difference regarding hemodynamic parameters at baseline between those who had a good outcome and those who did not. Eleven patients with a preoperative pulmonary blood flow to systemic blood flow ratio of <2:1. who had a good outcome following surgery, underwent repeat catheterization at follow-up. There was a significant reduction in their mean pulmonary vascular resistance (8.03+/-1.4 v. 4.16+/-1.6 Wood units, p=0.001) and pulmonary vascular resistance to systemic vascular resistance ratio (0.41+/-0.12 v. 0.19+/-0.06, p=0.05). CONCLUSIONS: The late results of surgery on this selected group of patients with nonrestrictive ventricular septal defect with high pulmonary vascular resistance are encouraging. Operative correction of the ventricular septal defect should be actively considered in all children presenting with nonrestrictive ventricular septal defect with a significant left-to-right shunt, despite moderately elevated pulmonary vascular resistance. Even among older patients with ventricular septal defect and moderately elevated pulmonary vascular resistance, there is a specific group that does well after operation.  相似文献   
6.
PALB2/FANCN is a BRCA1‐ and BRCA2‐interacting Fanconi Anemia (FA) protein crucial for key BRCA2 genome caretaker functions. Heterozygous germline mutations in PALB2 predispose to breast cancer and biallelic mutations cause FA. FA proteins play a critical role in the telomere maintenance pathway, with telomeric shortening observed in FA cells. Less is known about telomere maintenance in the heterozygous state. Here, we investigate the roles of PALB2 heterozygous mutations in genomic instability, an important carcinogenesis precursor. Patient‐derived lymphoblastoid (LCL) and fibroblast (FCL) cell lines with monoallelic truncating PALB2 mutations were investigated using a combination of molecular imaging techniques including centromeric FISH, telomeric Q‐FISH and spectral karyotyping (SKY). Mitomycin C and Cisplatin sensitivity was assayed via cellular metabolism of WST‐1. The PALB2 c.229delT FCL showed increases in telomere counts associated with increased mean intensity compared with two wild‐type FCLs generated from first‐degree relatives (P =1.04E‐10 and P =9.68E‐15) and it showed evidence of chromosomal rearrangements. Significant differences in centromere distribution were observed in one of three PALB2 heterozygous FCLs analyzed when compared with PALB2 wild‐type, BRCA1 and BRCA2 heterozygous FCLs. No significant consistently increased sensitivity to Mitomycin C or Cisplatin was observed in LCLs. Our results are suggestive of an altered centromere distribution profile and a telomere instability phenotype. Together, these may indicate critical nuclear organization defects associated with the predisposition to transformation and early stage development of PALB2‐related cancers. © 2013 Wiley Periodicals, Inc.  相似文献   
7.
A 43-year-old male with mirror-image dextrocardia and severe rheumatic mitral stenosis was subjected to successful percutaneous transvenous mitral commissurotomy (PTMC). The standard Inoue technique was modified by transseptal catheterization via the left femoral vein, image inversion, delineation of the interatrial septal anatomy via levophase pulmonary angiography, septal contrast staining and pigtail catheter insertion in the noncoronary aortic sinus, interatrial septal puncture with the transseptal needle rotated to a 7 o'clock position and left ventricular entry with a reverse loop technique. There were no procedural complications. Intracardiac pressures and mitral valvular planimetry suggested a successful procedural outcome. This case illustrates that PTMC can be accomplished safely in patients with this unusual cardiac anatomy with a few modifications in the standard technique.  相似文献   
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A novel diamine bis(4-aminophenyl)bis{3,4[(4-(8-quinolyloxymethyl carbonyl)]}methane, containing two long/bulky aromatic pendent chains was synthesized by incorporating aromatic and hetero aromatic groups with flexible linkages. Flexible, stretchable, thermally stable and processable polyimides were prepared by reacting this newly synthesized diamine with commercial tetracarboxylic acid dianhydrides like 3,3′,4,4′-benzophenone tetra carboxylic acid dianhydride (BTDA) and 4,4′-(4,4′-isopropylidenediphenoxy)diphthalic Anhydride (BPADA). Nanocomposites of polyimides were prepared using aromatic amine functionalized silica as a filler by solution casting method. The current work investigates the effects of incorporating long/bulky aromatic side chains and flexible linkages on the thermal, mechanical, electrical and optical properties of the polyimides and nanocomposites. The polyimides showed good thermal stability (T10% = 364 & 388), high flame resistance, low glass transition temperatures (Tg = 130 °C & 156 °C), very low dielectric constants (2.5 & 2.8 at 1 MHz) and good optical transparency. The neat polyimides displayed good elongation at break (133–155%) but possessed low tensile strength. The chemically imidized polyimides showed good solubility in low and high boiling solvents. Nanocomposites of polyimides based on aromatic amine functionalized silica exhibited enhanced properties with T10% values varying between 409–482 °C, Tg between 165–280 °C and higher dielectric constants (3–5.7 at 1 MHz).

Novel polyimides containing two long/bulky aromatic pendent chains and their nanocomposites with aromatic amine functionalized silica were prepared from a new diamine bis(4-aminophenyl)bis{3,4[(4-(8-quinolyloxymethyl carbonyl)phenoxy)]}methane.  相似文献   
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