Notes: This report is of a 62-year-old woman presenting with a 3-year history of chronic atrial fibrillation (AF) and unable to tolerate chronic warfarin therapy due to bleeding episodes and unstable INR values. Additional high risk factors for stroke are a history of congestive heart failure and previous embolic stroke. Percutaneous left atrial appendage transcatheter occlusion (PLAATO™) was performed to seal the LAA. A transesophageal echocardiography (TEE) at the 1- and 6-month follow-up showed no device migration and no new thrombus related to the implant. The patient has been doing well on postprocedure aspirin with no embolic events. (PACE 2003; 26[Pt. II]:1604–1606)

Notes: We report about the 6-month follow-up of 28 consecutive patients treated with a new tantalum stent (Wiktor™ stent, Medtronic, Inc.). Indication for stenting was the prevention of restenosis in eight patients (restenosis group), and threatening or acute closure after PTCA in 20 patients (acute closure group). Twenty-eight of 30 stents were successfully positioned in 27 of 28 patients (96%), whereas implantation failed twice in one patient. Immediate stent occlusion developed in two patients in the acute closure group (7.4%). Subacute stent occlusion was observed in three patients (11%), one in the restenosis group, two in the acute closure group, between 3 and 5 days after implantation. Coronary bypass surgery had to be performed in four patients (15%): one patient after failed stent placement, two after acute, and one after subacute stent thrombosis. Major bleeding complications related to the anticoagulative drug regimen occurred in nine patients (33%). Three patients (11%) died for reasons most probably not related to stent implantation. A 6-month angiographic follow-up revealed restenosis in two of 19 patients (11%), one patient in each group. Sixteen of the 27 stented patients (59%) reached 6-month follow-up without death, acute or subacute stent thrombosis, or restenosis. It is concluded that the Wiktor stent can be placed with a high rate of success. It may also reduce the risk of restenosis. The stent also offers the possibility to circumvent emergency bypass surgery in case of PTCA related vessel occlusion. Acute and subacute stent occlusion still remains an unsolved topic.

Notes: Patients with atrial fibrillation (AF) are at high risk of stroke. More than 15% of all strokes are due to atrial fibrillation. So far anticoagulation is the treatment of choice with a risk reduction of almost 70%. On the other hand, anticoagulation has many side effects such as intracranial or gastrointestinal hemorrhage. Closing the left atrial appendage (LAA) might be an alternative in patients who cannot take anticoagulation treatment due to contraindications or conditions in which the hazard of hemorrhage is greater than the potential clinical benefit. The PLAATO™ system (Percutaneous Left Atrial Appendage Transcatheter Occlusion) is a new device to close the LAA by the catheter technique. The device consists of a self-expandable nitinol cage that is covered with ePTFE™. It is delivered via a specially designed 12F transseptal sheath. Small anchors along the struts prevent the occluder from embolizing. After device implantation patients are placed on aspirin only. The results of the dog model and the first clinical experiences in humans have been very promising. (J Interven Cardiol 2003;16:553–556)

Notes: Paradoxical embolism through a patent foramen ovale (PFO) has been recognized as a potential cause of transient ischemia attack (TIA) and stroke especially in younger patients. The therapeutic options are medical treatment (antiaggregation or anticoagulation) with an annual recurrence rate of 3% to 4% for stroke or TIA, surgical PFO closure, or catheter closure. Randomized studies are ongoing; however, the results will not be available soon. Since August 1994, we have attempted catheter closure of a PFO in 281 patients (age 17 to 79 years, mean 46.8 ± 13.2) with paradoxical embolism. Of these, 184 patients had at least one embolic stroke, 112 patients at least one TIA, and 15 patients at least one peripheral embolism. The diameter of the PFO, measured with a balloon catheter, ranged from 3 mm to 24 mm with a mean of 10 ± 3.5 mm. Implantation of the occluder was technically successful in all patients (two attempts in four patients). Seven different devices were used: 26 Sideris buttoned, 11 ASDOS, 19 Angel Wings, 98 PFO-Star, 37 Cardioseal-Starflex, 57 Amplatzer and, 33 Helex devices. One patient suffered from septicemia and subsequently died. In 2 patients, device embolization occurred during or after the procedure (1 Sideris, 1 PFO-Star; catheter retrieval successful). Thirty-seven patients had other minor complications without long-term sequelae: atrial fibrillation within the first weeks after implantation in five patients, asymptomatic thrombus on the device at routine transesophageal echocardiogram (TEE) in 7 patients (I Angel Wings, 1 ASDOS, 1 CardioSeal, 4 PFO-Star), and device frame fracture in 25 patients (2 Sideris, 4 ASDOS, I Angel Wings, 1 CardioSeal, 17 PFO-Star). No complications occurred with the newer devices (Amplatzer and Helex). A residual shunt after 6 months was found in 5.5% of the patients who had completed their 6-month TEE follow-up. In two patients, a second occluder was implanted because of a residual shunt. During a follow-up period of 1 month to 71 months (mean 12 ± 16 months, 268 patient years), a recurrence of an embolic event (seven TIA, two stroke) occurred in eight patients. None of these occurred with the newer devices (Amplatzer, Helex). Freedom from recurrence of the combined end point of TIA, ischemic stroke, and peripheral embolism was 95.7% (95% CI: 89.0%–98.4%) at 1 year and 94.1 % (95% CI: 80.1–98.4%) at 3 years. Catheter PFO closure is a technically simple procedure. With the newer devices and increasing experience, the success rate has improved and the complication rate has decreased. The advantage of the procedure is that closing the defect means a causal treatment. However, catheter closure of PFO despite a very low morbidity has inherent potential risks like any other interventional procedure. Furthermore, selection of patients who definitely have PFO as the cause of their cerebral event has not been defined. For these reasons, further studies are warranted. (J Interven Cardiol 2001; 14:261–266)

Notes: Background: Atrial septal aneurysm is frequently associated with patent foramen ovale (PFO) and atrial septal defects (ASD). Moreover, a relationship between atrial septal aneurysm and embolic cerebrovascular events has been suggested. The aims of this study were to analyze morphological and functional characteristics of atrial septal aneurysm in PFO and ASD patients and to assess the feasibility and eficacy of different devices for transcatheter closure and the influence of atrial septal aneurysm. Methods: Between March 1997 and May 2000 transcatheter ASD or PFO closure was attempted in 63 patients (mean age 47 ± 13 years) with an atrial septal aneurysm using one of the following devices: Angelwings (n = 3), Cardioseal (n = 5), Cardioseal-Starflex (n = 7), Amplatzer (n = 11), Amplatzer-PFO (n = 5), PFO-Star (n = 25), or Helex (n = 7). Results: Implantation was primarily successful (after the first or second attempt) in all patients. One PFO-Star device embolized 12 hours after the procedure. During follow-up (0.6–37 months, mean 10.4 ± 9.2) a residual shunt could be detected by transesophageal echocardiography after 2 weeks in four patients and after 6 months in one patient. Three PFO patients had cerebrovascular events after implantation. Two patients had a transient ischemic attack (TIA) and one patient a stroke. A thrombus formation on the device detected in three patients disappeared after antithrombotic therapy. Conclusion: We conclude that ASDs and PFOs with an associated atrial septal aneurysm can be closed with different available devices. There seem to be no additional risks compared with patients without atrial septal aneurysm. (J Interven Cardiol 2001;14:49–55)

Notes: New techniques and devices have revolutionized the transcatheter techniques used to close congenital intracardiac shunts. The advantages, compared to surgery, are the avoidance of a thoracotomy, postoperative pain and morbidity, a long hospital stay, and most often general anesthesia. Atrial septal defect closure has become a routine procedure in many centers. It is amenable in about 80% of the patients with a secundum-type defect. The success rate today is dx 〉 99% and the rate of any complication is 〈 0.5%. Ventricular septal defect closure, however, is still in its infancy. Apical, mid-muscular, and selected perimembraneous VSDs with a significant septal rim between the defect and the aortic valve can be closed with the devices currently available. Analysis is still needed to prove the long-term safety and efficacy of ASD or VSD closure.

Notes: Sixteen balloon expandable Medtronic Wiktor tantalum stents were implanted in the major coronary arteries of six minipigs, which were maintained on a normal diet and given 500 mg aspirin per day. Angiographic and histologic examinations were performed 6 and 26 weeks after implantation. Angiographically reviewed, stenting increased the inner diameter of the coronary arteries from 2.61 ± 0.44 to 3.02 ± 0.34 mm (n = 16, P ≤ 0.001). Six weeks later, this value was reduced from 2.98 ± 0.35 to 2.33 ± 0.46 mm (n = 9, P ≤ 0.05), and between 6 and 26 weeks, an increase from 2.17 ± 0.44 to 2.93 ± 0.40 mm occurred (n = 6, P ≤ 0.05). Histologic evaluation at 26 weeks after stent implantation revealed an increase of the cross-sectional area of the total vessel from 4.30 ± 1.09 to 5.50 ± 1.67 mm2 (n = 9; P ≤ 0.01). This was due to widening of the total vessel and intimal proliferation, which amounted to 1.19 ± 0.46 mm2 within the stented segment, as compared to 0.03 ± 0.03 mm2 in control sections (P ≤ 0.01). The areas of free vessel lumen, media muscularis, and adventitia remained unchanged. In 15 of the 16 hislologically examined coronary arteries, the internal elastica was fractured at the site of stent implantation. Twelve stents had also penetrated through the external elastica without evidence of wall hemorrhage. Thirteen out of 16 stents were angiographically followed, of which 12 were patent at the final reangiography. In one animal, acute thrombosis of the stented vessel after guidewire induced coronary artery spasm caused chronic right heart failure due to right ventricular myocardial infarction. Sudden death occurred in another pig 2 hours after successful implantation of three grossly oversized stents (inner vessel diameter: 2.4 ± 0.2 mm, stent diameter 3.2 ± 0.5 mm). Autopsy revealed extensive dissections of the media with subsequent vessel occlusion. It is concluded that Medtronic Wiktor stents can be placed easily, even in more distal or curved coronary arteries. Despite antiaggregational medication, intimal proliferation is observed early after implantation, reaches a maximum at about 6 weeks, and is followed by a regression 26 weeks poststenting. At 26 weeks follow-up, the free vessel lumen at the stent site was not significantly reduced as compared to control segments. Proper adjustment of internal vessel diameter and stent diameter is necessary to prevent major dissections and thrombotic occlusions.

Notes: Carotid artery stenting (CAS) is growing as an alternative to carotid artery endarterectomy. Nowadays, it is performed routinely in many centers worldwide. Still, it is discussed controversially although several clinical trials have shown equivalency or superiority of catheter treatment at least in high-risk patients. What is still missing is a randomized trial in non-high-risk patients. This is an overview about the completed and ongoing trials as well as the current stent and embolic protection technology.

Notes: The most common complication of carotid angioplasty is distal embolization of debris and/or thrombus. The only way to avoid this complication is with the use of embolic protection devices. Several filters, distal balloon occlusion devices, and proximal balloon occlusion devices are available. These devices make it possible to capture arteriosclerotic debris during angioplasty and stenting. During the majority of procedures at least some particles can be retrieved. Therefore there is no doubt that these devices are important for carotid angioplasty. However, due to the low complication rate of carotid angioplasty even without embolic protection devices, large randomized trials are necessary to statistically prove the clinical efficacy of these devices.