Search PubMed⌕ Search

Biomedical subjects

A Formanek

Publications and source records attributed to A Formanek.

At least 19 recordsLinked to original sources

Transcatheter closure of secundum atrial septal defects using the new self-centering amplatzer septal occluder: initial human experience.

Transcatheter closure of secundum atrial septal defect (ASD) using clamshell or buttoned devices is accompanied by a high incidence of residual shunt. Recently, a new self-centering device, the Amplatzer septal occluder (ASO), has been evaluated in an animal model with very good results. Therefore, our purpose is to report on our initial clinical experience with this device. Thirty patients underwent an attempt at catheter closure of their ASDs at a median age of 6.1 yr (range, 2.9-62.4 yr) and median weight of 22 kg (range, 13-69 kg) using the ASO. The median ASD diameter measured by transesophageal echocardiography (TEE) was 12.5 mm (range, 5-21 mm), and the median ASD balloon stretched diameter was 14 mm (range, 7-19 mm). All patients had right atrial and ventricular volume overload with a mean +/- SD Qp/Qs of 2.3 +/- 0.6. A 7F catheter was used for delivery of the device in all patients. The device was placed correctly in all patients. There was immediate and complete closure (C) in 17/30 patients, 10 patients had trivial residual shunt (TS), and 3 had moderate residual shunt (MS). The median fluoroscopy time was 15 min (range, 8-35 min), and the median total procedure time was 92.5 min (range, 40-135 min). There was no episode of device embolization or any other complication. Follow-up was performed using transthoracic echocardiography (TTE) 1 day, 1 mo, 3 mo, and yearly thereafter. At 1 day, there was C of the ASD in 24/30 patients, 3 had TS, 1 had small shunt (SS), and 2 had MS. At a median follow-up interval of 6 mo, there have been no episodes of endocarditis, thromboembolism, or wire fracture. We conclude that the use of the new ASO is safe and effective in complete closure of secundum ASDs up to a diameter of 21 mm in the majority of patients. Further clinical trials are underway.

Adolescent↗

Single versus biplane right and left ventricular volumetry: a cast and clinical study.

True volume (y) and measured volume (x) determined from 23 right and 22 left normal human casts in four biplane angiographic positions and in their eight single-plane components were used to find the correction factor (b) by regression through the origin (y = bx). The correction factors were applied to human studies to assess the validity of the various biplane and single-plane modalities in vivo. The casts studies yield excellent correlations in both right and left biplane methods (right volumetry: 0.555 less than or equal to b less than or equal to 0.708, 0.917 less than or equal to r less than or equal to 0.954, 4.10 less than or equal to SEE less than or equal to 6.01 left volumetry: 0.748 less than or equal to b less than or equal to 0.825, 0.974 less than or equal to r less than or equal to 0.982, 4.81 less than or equal to SEE 5.79). Good results were obtained with single-plane volumetries as well (right volumetry: 0.316 less than or equal to b less than or equal to 0.887, 0.750 less than or equal to r less than or equal to 0.917, 10.75 less than or equal to SEE less than or equal to 18.96; left volumetry: 0.728 less than or equal to b less than or equal to 0.881, 0.897 less than or equal to r less than or equal to 0.976 5.73 less than or equal to SEE less than or equal to 11.97). The correction factors for the single-plane studies depend much more strongly on the spatial position relative to the radiographic system, particularly in the case of the right ventricular volumes. Thus, the application of the appropriate correction factors is mandatory. The human studies (141 left and 60 right volumetric studies in various single-plane and biplane projections) showed a larger scatter of single-plane values, more pronounced for the right ventricle. In certain disease conditions, single plane volumetric studies using cast-derived correction factors cannot be used to obtain meaningful results. Correction factors for the following single or biplane mode volumetry are presented for the first time: biplane hepatoclavicular view (right and left ventricle), biplane long axial oblique view (right ventricle), and their single-plane components; lateral and 60 degree Left Anterior Oblique (LAO) single plane for the left-sided measurements, Postero-Anterior (PA), lateral, and 60 degree LAO for the single-plane right-sided calculations.

Angiocardiography↗

Transvenous embolization of internal spermatic veins: nonoperative approach to treatment of varicocele.

Eleven men, shown on routine spermatic venography to have bilateral varicocele, underwent transjugular bilateral embolization of the internal spermatic veins with stainless steel coils or Ivalon plugs. Embolization of the left spermatic vein was successful in 9; in the other 2 it was not attempted because of aberrant drainage of the vein. Embolization of right spermatic vein was successful in 8 patients. There were three complications, none of which was serious. These preliminary results suggest that both internal spermatic veins can be occluded consistently by the transjugular approach. However, it has not yet been established that fertility is improved by detecting and correcting varicocele on the right side.

Embolization, Therapeutic↗

Embolization of the spermatic vein for treatment of infertility: a new approach.

A new transjugular technique for spermatic venography and nonsurgical transcatheter occlusion of incompetent spermatic veins is described. With this technique, the left spermatic vein was easily catheterized in 28 of 30 patients examined, and in 21 patients the vein could be occluded. Right spermatic vein catheterization was attempted in 25 patients. Right-sided spermatic vein occlusion was successful in 17 of 24 patients. The vein could not be selectively entered only twice. Bilateral incompetence of the spermatic veins in men with primary sterility is the rule rather than the exception. Valvular incompetence does not necessarily produce a clinically detectable varicocele. Bilateral venography is indicated in all men with abnormal spermiograms.

Adult↗

The three types of criss-cross heart: a simple rotational anomaly.

Criss-cross heart is an angiographically confusing malformation where apparent crossing but not mixing of contrast medium is seen at atrioventricular level. The malformation can be understood by a clockwise or counter-clockwise ventricular rotation. In the normal heart or one with complete transposition ventricular rotation is clockwise. With corrected transposition rotation occurs in a counter-clockwise fashion. One case of criss-cross heart with associated corrected transposition and two criss-cross hearts occurring with complete transposition are reported.

Heart↗

Aberrant left subclavian artery in tetralogy of Fallot.

The anatomy of the aberrant left subclavian artery in a right-sided aortic arch is different in patients with tetralogy of Fallot than in persons with a normal heart. In all eight patients with tetralogy of Fallot and aberrant left subclavian artery in this series, the left subclavian artery arose directly from the distal aortic arch. In contrast, normal persons with right aortic arch and aberrant left subclavian artery invariably have an aortic diverticulum from which the left subclavian artery and the left ductus arteriosus originate. The possible different embryologic events responsible for these two forms of aberrant left subclavian artery are discussed.

Aorta, Thoracic↗

Noninvasive localization of the aortic arch in infants with tracheoesophageal fistula: an experimental study.

For surgical treatment of patients with tracheoesophageal fistulas the localization of the aortic arch is great practical importance. Aortography and CT scanning have been advocated as the radiographic techniques of choice. The location of the aortic arch can be diagnosed on a chest x-ray by the deviation of the trachea alone. A barium swallow is not required. The optimal radiographic technique for this purpose was investigated in phantom studies and tested in animals and newborns. It is proposed that in addition to the standard chest x-ray a high kvp film with hardened beam (1 mm copper -- 1 mm aluminum) be added in order to demonstrate the tracheal deviation. The additional x-ray exposure to the infant is negligible; and the technique is simple, reliable, and noninvasive.

Animals↗

The multiple faces of fibromuscular dysplasia of the renal arteries.

For surgical treatment of patients with FMD of the renal arteries an optimal angiographic study is necessary. Preferably aortography as well as selective magnification renal angiography should be carried out. Oblique views may be necessary to demonstrate the peripheral extension into segmental branches, collateral circulation, the presence of aneurysms, and/or associated complications as AV fistulas, infarctions, intramural hematomas and pseudoaneurysms.

Adolescent↗

Cystic arterial adventitial degeneration.

Cystic degeneration of the adventitia is a rare entity occurring most commonly in the popliteal artery: only a few cases involving the external iliac, femoral, radial, and ulnar arteries have been reported. The authors describe 2 cases, one of which appears to be the first report of the disease in the external iliac artery in a child.

Adolescent↗

Embolization of multiple pulmonary artery fistulas.

Therapeutic embolization of pulmonary arteriovenous fistulas is described as an alternate method of treatment for patients with diffuse pulmonary involvement in whom resection is not feasible.

Arteriovenous Malformations↗

Nonsurgical aortoplasty in Leriche syndrome.

The abdominal aorta was dilated with a pair of 9-mm balloon catheters in a patient with Leriche syndrome. The bilateral pressure gradient, initially 60 mm Hg, disappeared even after papaverine was injected. Balloon dilatation of the abdominal aorta may be an effective, safe nonsurgical technique, particularly in localized, noncalcified atheromata, and does not carry the risk of impotence seen with surgical endarterectomy or bypass.

Aorta, Abdominal↗

Coronary sinus-left atrial window.

Left atrial-coronary sinus fenestration is a rare cause of a left-to-right or right-to-left shunt which occurs most commonly with a persistent left superior vena cava. These fenestrations may represent the only pathway for an obligatory right-to-left or left-to-right shunt in atrioventricular valve atresia. Four cases are presented.

Abnormalities, Multiple↗

Scanography with rotation of the radiographic tube: a new method.

The quality of the radiographic image is compromised by secondary radiations and geometric unsharpness, which is proportional to the focal spot size. The authors describe a new system which significantly improves both elimination of scatter and reduction of the apparent focal spot size and gives superior radiographs to those made with a conventional x-ray machine. Advantages of the new system include (a) the lack of resolution and density gradients across the radiograph, (b) increased contrast due to descreased scatter, (c) increased resolution, (d) possible routine radiography with a 100-mu focal spot, (e) up to 2.5 x magnification, (f) increased acceptable kVp range, and (g) decreased dose to the patient.

Humans↗

The mechanism of balloon angioplasty.

A new theory of the mechanism of percutaneous arterial angioplasty is advanced. For this study, abdominal aortas and coronary, renal, superior mesenteric, and iliac arteries were obtained from cadavers. In addition, the iliac arteries of dogs were dilated and studied. No evidence of significant compression or redistribution of plaques could be found, supporting the theory that atheromatous material is incompressible. Cracking of the intima and separation of it from the media were histologically demonstrated following angioplasty. It is proposed that the stretched media distends following dilatation, carrying with the intima and atheromatous material. Once the media is freed from the encasing effect of the intima, it adapts to the circulatory needs of the body. Beyond a certain point, the arterial widening becomes permanent, due to an overstretching of the muscle fibers, which is demonstrated by a corkscrew deformity of the muscle cell nuclei.

Aged↗