Experience in one centre using the buttoned device for occlusion of atrial septal defect: comparison with the Amplatzer septal occluder.

We report our experience using the buttoned device to close defects within the oval fossa and probe-patent oval foramens, comparing the findings with those obtained with the Amplatzer septal occluder. From 1992 to 1997, we used the buttoned device to close defects in 73 consecutive patients, 64 with defects in the oval fossa and nine with patent foramens. We compared this experience with a further series of 62 patients seen from 1997 to 1999 in whom the Amplatzer septal occluder was used. Successful implantation was achieved in three-quarters of those with septal defects in whom the buttoned device was used, in all of those in whom the buttoned device was used for patent foramens, and in nine-tenths of those in whom closure was attempted using the Amplatzer occluder. Immediate surgery was needed in 3 patients in whom a buttoned device was used, one because of embolization and two with residual shunts and a straddling device. Similar immediate surgery was needed to retrieve one embolized Amplatzer occluder. During follow-up, surgery was needed in a further 7 patients, all having had insertion of a buttoned device, because of atrial perforation in one and a significant residual shunt in the remainder. At late follow-up, the rate of complete occlusion was 69% in the patients in whom the buttoned device was used to close a septal defect, 100% when the buttoned device was used for patent foramens, and 95% in those treated with the Amplatzer occluder. Our experience shows that the Amplatzer occluder produced a significantly higher rate of occlusion for larger defects, and with a shorter fluoroscopy time than the buttoned device. The Amplatzer septal occluder, therefore, is our preferred device for closure of defects within the oval fossa.

Right atrial thrombi: percutaneous mechanical thrombectomy.

The current therapeutic options for right atrial thrombi-surgical embolectomy and thrombolysis-are associated with high mortality and such patients often have contraindications to these therapeutic options. The purpose of this study was to evaluate the feasibility of endovascular right atrial embolectomy. Two patients with contraindications to thrombolysis and surgery were treated by a femoral approach. A catheter was placed in the right atrium, under fluoroscopic control, and a basket device was used to trap the thrombus. The location and extent of the thrombus was established before the procedure by transesophageal echocardiography (TEE) and the procedure was performed with TEE and fluoroscopy. Thrombi were withdrawn in the basket into the inferior vena cava (IVC) and a filter was inserted by a jugular approach and positioned in the IVC, just above the thrombi. The basket was removed leaving the thrombus below the filter. One patient died immediately after the procedure. In conclusion, endovascular extraction of right atrial thrombi may represent a potential therapeutic alternative, particularly in patients with contraindications to thrombolysis and surgery.

Helical CT angiography compared with arteriography in the detection of renal artery stenosis.

OBJECTIVE: The aim of the study was to improve the accuracy and detection rate for renal vascular lesions on helical CT angiography with an improved acquisition protocol and postprocessing. SUBJECTS AND METHODS: Fifty hypertensive patients (man age, 53 years old) referred because of clinical suspicion on renal artery stenosis were prospectively studied with digital renal arteriography and helical CT angiography. A 20-sec helical scan (collimation, 3 mm; pitch, 1) was obtained after injection of contrast medium. Interpretation was base on transverse sections, shaded-surface-display and maximum-intensity-projection reconstructions, and two-dimensional multiplanar reconstruction cuts obtained from shaded-surface-display reconstructions. RESULTS: Arteriography visualized 131 renal arteries (including 32 accessory arteries). Sixteen had significant (greater than 50% in diameter) stenosis. On helical CT angiography, 14 of these 16 stenoses were detected; two were missed (false-negatives), and two additional stenoses (false-positives) were reported. Sensitivity and specificity were 88% and 98%, respectively. Considering only main renal arteries, the sensitivity and the specificity of helical CT angiography were 100% and 98%, respectively. Helical CT angiography detected Conn's syndrome, which was responsible for hypertension, in two other patients. CONCLUSION: The accuracy and detection rate for renal artery stenosis on helical CT angiography compared with arteriography is improved with the described protocol.

Case report. Congenital left ventricular aneurysm diagnosed by spiral CT angiography.

We report a rare case of congenital left ventricular aneurysm, diagnosed by spiral CT angiography. Despite 1 s time acquisition, spiral CT, with adequate acquisition parameters and bolus injection of contrast medium, produced sufficiently good images to permit visualization of the aneurysm. Subsequently, reconstructions (shaded surface display and multiplanar reformation) were performed to demonstrate the relationship of the aneurysm with the remainder of the left ventricle, the wide neck of the aneurysm, and the absence of contractility, therein permitting differentiation from a congenital diverticulum.

[French experience in the closure of atrial septal defects of the ostium secundum type with the Sideris button occluder]. / Expérience française de la fermeture des communications interauriculaires de type ostium secundum par la prothèse boutonnée de Sideris.

From February 1992 to November 1995, four French teams used the Sideris button occluder to close 122 ostium secundum, foramen ovale or surgical fenestration atrial septal defects in 121 patients aged 2 to 79 years with body weights of 10 to 96 kg. a left-to-right shunt in 110 cases (average QP/QS = 2.09) or right-to-left shunt in 12 cases. The usual type of prosthesis was used in 115 cases, 8 centered on a guide wire, reverse type in 5 cases and the "centering-device" type in 2 patients. Nineteen implantation attempts were abandoned before releasing the prosthesis. The immediate results were: closure of the atrial septal defect in 116 patients: 59 were completely occluded, 43 had minimal residual shunts. Five patients were operated for non-buttoning or malposition of the prosthesis. In one other case, the device was removed by catheterisation. During follow-up ranging from 1 month to 3 years, 20 patients were operated for varying complications, the commonest of which was malposition of the prosthesis (17 cases) with a shunt of variable volume. In one other case, a second device was inserted. Seventy-seven patients were reviewed at 1 year, 28 a 2 years and 6 at 3 years. The residual shunts decreased with time but only completely disappeared in half the cases. Secondary fractures not requiring surgery were observed in 5 patients. Failures and complications were the result of various causes which are discussed. Successive technological improvements and the experience of the medical teams should reduce this incidence, but caution is required especially in the treatment of young children.

[Percutaneous implantation of endoprostheses in stenosis of the pulmonary branches]. / Implantation percutanée d'endoprothèses dans les sténoses des branches pulmonaires.

Between July 1992 and October 1995. 10 Palmaz stents were implanted in 6 patients aged 2 to 25 years with stenoses of pulmonary artery branches. The stenoses were located on the right (n = 2) or left pulmonary artery (n = 3) or both branches (n = 1). Stenoses of the right pulmonary artery were secondary to a Waterston (n = 1) or Blalock-Taussig (n = 1) anastomosis or to surgical plasty with Dacron (n = 1). Stenoses of the left pulmonary artery were secondary to surgical plasty with Goretex (n = 2), pericardium (n = 1) or Dacron (n = 1): three of these patients had undergone a left Blalock-Taussig anastomosis before complete correction. After implantation of the stent, the pulmonary artery diameter increased from 4 +/- 2 mm to 11 +/- 2 mm (p = 0.0117) and the transstenotic gradient decreased from 44 +/- 18 to 15 +/- 12 mmHg (p = 0.0277). Similarly, the percentage of homolateral pulmonary perfusion at scintigraphy increased from 22 +/- 13% to 53 +/- 17% (p = 0.0431). There were no deaths. The major complication was migration of the stent, observed in three patients at the moment of implantation in two cases and in the hours following implantation in the other case. In these 3 patients, the embolised stent was left in the pulmonary arteries with no adverse consequences on pulmonary perfusion. Two of these patients later successfully underwent further catheterisation for implantation of another stent. Implantation of a stent is a therapeutic alternative in pulmonary artery stenoses which often recur after surgery and/or angioplasty. They increase the diameter of the stenosed vessel and reestablish the equilibrium of perfusion between the two lungs.

Effects of a modified Q-switched Nd-YAG laser on human vascular tissue: an ex vivo study.

RATIONALE AND OBJECTIVES: Relatively disappointing results with continuous-wave lasers stimulated us to evaluate pulsed lasers for interventional radiology. In this article, we describe our efforts to assess the effects of this technology ex vivo. METHODS: We modified a Q-switched yttrium aluminum garnet (Nd-YAG) laser to emit pulses of 300 mJ maximum with a 20-Hz repetition rate, at 1064 nm, and with a duration that ranged from 300 ns to 2.3 microseconds. The lengthening of the pulse duration by a factor of 100 (compared with the conventional nanosecond Q-switched Nd-YAG laser) and the ability to define it exactly were obtained by controlling the opening and closing of the Pockels cell electronically. Lengthening the pulse duration made it possible to reduce peak power while conserving the same total energy. In this way, high energy was transmitted through thin optical fibers. RESULTS: One hundred fifty millijoules with 2-microsecond pulses, 140 mJ with 1-microsecond pulses, and 100 mJ with 500-ns pulses were transmitted through a 300-micron silica-polymer fiber. The transmission coefficient was identical for the three pulse durations. Ex vivo irradiation experiments were performed on human atheromatous arteries in saline solution using a 300-micron diameter optical fiber. Craters were easily obtained. Their depth and width were related to maximum energy transmission and irradiation time. No carbonization occurred and no destruction of the optical fiber was observed. CONCLUSION: A modified Q-switched Nd-YAG laser can transmit high-energy pulses through thin optical fibers without damaging them and can destroy human atheroma in an ex vivo setting.

Long-term follow-up after peripheral and coronary angioplasty in patients undergoing both types of procedure.

Restenosis rates after peripheral and coronary angioplasties have been assessed only in patients who had either peripheral angioplasty or coronary angioplasty but never in patients who had both types. Among the 6364 angioplasties performed in the authors' institution since 1980, they studied 38 patients (36 men, 2 women, mean age fifty-five years, range thirty-four to seventy-seven) who had both peripheral and coronary angioplasty. The peripheral angioplasties were most often performed on iliac artery stenoses. They were performed before coronary angioplasty in 22 patients (58%) and after coronary angioplasty in 16 patients (42%). The follow-up after peripheral angioplasty was based on clinical data; ultrasound investigation was performed when the result of the clinical follow-up was poor (maximal walking distance lower than 500 meters). Follow-up after coronary angioplasty was assessed by a systematic coronary angiography at six months and with long-term clinical follow-up. The mean durations of the follow-up after peripheral or coronary angioplasty were not significantly different (respectively fifty-six +/- eleven and forty-two +/- nine months [mean +/- 2 SEM]). No patient was lost to clinical follow-up; 17 (45%) ultrasound investigations, 12 (32%) peripheral angiographies, and 34 (89%) coronary angiographies were performed. The restenosis rate after peripheral angioplasty was 18% and that after coronary angioplasty was 34%. These rates are similar to the classic rates observed in the literature. In conclusion, as reported for either procedure alone, the restenosis rates after peripheral angioplasty and after coronary angioplasty are different when assessed in patients who undergo both types of angioplasty.