302 research outputs found
The adult with congenital heart disease: Cardiac catheterization as a therapeutic intervention
AbstractThe adult with congenital heart disease who undergoes cardiac catheterization at the present time is most likely to have complex heart disease and is left with clinically important sequelae or residual defects, ventricular dysfunction or arrhythmias. Residual defects such as paravalvular leaks, coronary fistulas and pulmonary artery narrowings may be corrected with transcatheter techniques. Patients with simple forms of congenital heart disease (for example, atrial septal defect patent ductus arteriosus, aortic valve stenosis, pulmonary valve stenosis) will go to the catheterization laboratory for treatment, not diagnosis. Certain lesions previously considered benign (for example, patent foramen ovale) may require definitive interventional therapy to reduce the risk of stroke from paradoxic embolism
Scattering of a Tightly Focused Beam by an Optically Trapped Particle
Near-forward scattering of an optically trapped 5 m radius polystyrene latex sphere by the trapping beam was examined both theoretically and experimentally. Since the trapping beam is tightly focused, the beam fields superpose and interfere with the scattered fields in the forward hemisphere. The observed light intensity consists of a series of concentric bright and dark fringes centered about the forward scattering direction. Both the number of fringes and their contrast depend on the position of the trapping beam focal waist with respect to the sphere. The fringes are caused by diffraction due to the truncation of the tail of the trapping beam as the beam is transmitted through the sphere
Combined effects of nitric oxide and oxygen during acute pulmonary vasodilator testing
AbstractOBJECTIVESWe compared the ability of inhaled nitric oxide (NO), oxygen (O2) and nitric oxide in oxygen (NO+O2) to identify reactive pulmonary vasculature in pulmonary hypertensive patients during acute vasodilator testing at cardiac catheterization.BACKGROUNDIn patients with pulmonary hypertension, decisions regarding suitability for corrective surgery, transplantation and assessment of long-term prognosis are based on results obtained during acute pulmonary vasodilator testing.METHODSIn group 1, 46 patients had hemodynamic measurements in room air (RA), 100% O2, return to RA and NO (80 parts per million [ppm] in RA). In group 2, 25 additional patients were studied in RA, 100% O2and 80 ppm NO in oxygen (NO+O2).RESULTSIn group 1, O2decreased pulmonary vascular resistance (PVR) (mean ± SEM) from 17.2 ± 2.1 U·m2to 11.1 ± 1.5 U·m2(p < 0.05). Nitric oxide caused a comparable decrease from 17.8 ± 2.2 U·m2to 11.7 ± 1.7 U·m2(p < 0.05). In group 2, PVR decreased from 20.1 ± 2.6 U·m2to 14.3 ± 1.9 U·m2in O2(p < 0.05) and further to 10.5 ± 1.7 U·m2in NO+O2(p < 0.05). A response of 20% or more reduction in PVR was seen in 22/25 patients with NO+O2compared with 16/25 in O2alone (p = 0.01).CONCLUSIONSInhaled NO and O2produced a similar degree of selective pulmonary vasodilation. Our data suggest that combination testing with NO+O2provides additional pulmonary vasodilation in patients with a reactive pulmonary vascular bed in a selective, safe and expeditious fashion during cardiac catheterization. The combination of NO+O2identifies patients with significant pulmonary vasoreactivity who might not be recognized if O2or NO were used separately
OUTCOMES AFTER IMPLANTATION OF BARE-METAL, COVERED AND DRUG-ELUTING STENTS FOR THE TREATMENT OF PULMONARY VEIN STENOSIS IN CHILDREN
Nachrichten aus Frankfurt, Alexander Linneman
Surgical management of subaortic obstruction in single left ventricle and tricuspid atresia
Subaortic obstruction caused by either a restrictive bulboventricular foramen in single left ventricle with an outflow chamber or by a restrictive ventricular septal defect in tricuspid atresia with transposition of the great arteries can lead to a hypertrophied, noncompliant ventricle and excessive pulmonary blood flow. This combination is disadvantageous to potential Fontan procedure candidates because they are dependent on good ventricular function and low pulmonary vascular resistance for survival.The results of surgical procedures to directly or indirectly relieve significant subaortic obstruction (gradient 30 mm Hg) in 24 patients, 16 with single left ventricle and 8 with tricuspid atresia, were reviewed. Four patients had a left ventricular apex to descending aorta valved conduit; none survived. Seven patients had resection of subaortic tissue; four survived and four developed heart block at surgery. Adequate gradient relief was evident in only one of the four survivors. Thirteen patients had a main pulmonary artery to ascending aorta anastomosis or conduit; six survived. AH survivors had adequate gradient relief. The overall survival was 42% (10 of 24). None of seven patients with a subaortic gradient >75 mm Hg survived.These data show that: 1) Surgical relief of established subaortic obstruction in patients with single left ventricle and tricuspid atresia carries a high mortality rate, especially if the subaortic gradient is >75 mm Hg. 2) The best procedure appears to be the pulmonary artery to ascending aorta anastomosis. 3) A clearer understanding of the factors leading to the development of significant subaortic obstruction is necessary to prevent it or to devise improved therapeutic strategies
Transcatheter closure of a large patent ductus arteriosus with the clamshell septal umbrella
AbstractIn 14 patients undergoing transcatheter closure of a large (>4 mm diameter) patent ductus arteriosus, occlusion was attempted with use of the Bard Clamshell septal umbrella. Patient age ranged from 0.7 to 30.4 years. Isolated patent ductus arteriosus was present in 11 patients; 3 had additional congenital heart lesions. Moderate or severe pulmonary hypertension was present in four patients. The diameter of the patent ductus arteriosus ranged from 4.5 to 14 mm, as determined by contrast injection through an 11F sheath or by balloon sizing; it appeared larger by this method than by the standard angiographic method.All 14 patent ductus arteriosi were successfully closed. Prior embolization of a Rashkind umbrella was the reason for using a Clamshell device in three patients; one additional embolization of a Clamshell device occurred. All errant devices were retrieved at cardiac catheterization, without associated hemodynamic instability. No other complications occurred. Among the 14 patients, 11 had complete ductal closure by Doppler color flow mapping at last follow-up and 3 had trivial residual Row. All four patients having associated complex lesions or pulmonary hypertension, or both, had symptomatic improvement after the procedure, although one child (with Shone's anomaly) died 3 months later.The Clamshell device provides stable and effective closure of a large patent ductus arteriosus, and allows transcatheter closure to be offered to some patients who were previously considered unsuitable for this procedure
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