| 81. |
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| 82. |
- Malina, Martin, et al.
(författare)
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Changing aneurysmal morphology after endovascular grafting: relation to leakage or persistent perfusion
- 1997
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Ingår i: Journal of Endovascular Surgery. - 1074-6218. ; 4:1, s. 23-30
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: To relate changing abdominal aortic aneurysm (AAA) morphology after endovascular grafting to the presence of leakage, collateral perfusion, and other factors. METHODS: Thirty-five patients who underwent successful AAA endovascular grafting were evaluated. Self-expanding Z-stents and Dacron grafts were applied in bifurcated and aortomonoiliac systems. Postoperative diameter changes were calculated from repeated spiral computed tomographic scans, angiograms, and ultrasonic phase-locked echo-tracking scans during a median 6-month follow-up (interquartile range [IQR] 3 to 12). RESULTS: At 12 months, the diameters of completely excluded aneurysms had decreased 6 mm (IQR 2 to 11; p = 0.006). The proximal graft-anchoring stents had dilated 2 mm (IQR 0.5 to 3.3; p = 0.01). The aortic diameters immediately below the renal arteries but above the stents had not changed. Endoleakage and collateral perfusion (n = 13) were each associated with preserved aneurysm size and a 12 times higher risk of aneurysm dilation. After the leakage or the collateral perfusion had been treated, the aneurysm size decreased. Aneurysms with extensive intraluminal thrombi presented a reduced risk of leakage or perfusion. CONCLUSIONS: The diameters of endovascularly excluded AAAs decrease, except in cases of leakage or perfusion. Careful follow-up of patients with aortic endografts is necessary.
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| 83. |
- Malina, Martin, et al.
(författare)
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Endovascular AAA exclusion: will stents with hooks and barbs prevent stent-graft migration?
- 1998
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Ingår i: Journal of Endovascular Surgery. - 1074-6218. ; 5:4, s. 310-317
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: To investigate if stents with hooks and barbs will improve stent-graft fixation in the abdominal aorta. METHODS: Sixteen- to 24-mm-diameter Dacron grafts were deployed inside cadaveric aortas. The grafts were anchored by stents as in endovascular abdominal aortic aneurysm repair. One hundred thirty-seven stent-graft deployments were carried out with modified self-expanding Z-stents with (A) no hooks and barbs (n = 75), (B) 4 5-mm-long hooks and barbs (n = 39), (C) 8 10-mm-long, strengthened hooks and barbs (n = 19), or (D) hooks only (n = 4). Increasing longitudinal traction was applied to determine the displacement force needed to extract the stent-grafts. The radial force of the stents was measured and correlated to the displacement force. RESULTS: The median (interquartile range) displacement force needed to extract grafts anchored by stent A was 2.5 N (2.0 to 3.4), stent B 7.8 N (7.4 to 10.8), and stent C 22.5 N (17.1 to 27.9), p < 0.001. Both hooks and barbs added anchoring strength. During traction, the weaker barbs were distorted or caused intimal tears. The stronger barbs engaged the entire aortic wall. The radial force of the stents had no impact on fixation, while aortic calcification and graft oversizing had marginal effects. CONCLUSIONS: Stent barbs and hooks increased the fixation of stent-grafts tenfold, while the radial force of stents had no impact. These data may prove important in future endograft development to prevent stent-graft migration after aneurysm exclusion.
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| 84. |
- Malina, Martin, et al.
(författare)
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Endovascular management of the juxtarenal aortic aneurysm: can uncovered stents safely cross the renal arteries?
- 1999
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Ingår i: Seminars in Vascular Surgery. - 0895-7967. ; 12:3, s. 182-192
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Tidskriftsartikel (refereegranskat)abstract
- A short or otherwise suboptimal neck precludes the use of endovascular repair in 30% to 50% of patients with abdominal aortic aneurysms. Stent-graft fixation in an unsuitable neck carries the risk of technical failure owing to development of a proximal endoleak or stent-graft migration. Furthermore, in some patients, the neck dilates postoperatively. Endovascular healing with tissue incorporation into the graft material seems in and of itself insufficient to fixate the stent-graft adequately or to prevent neck dilation. Therefore, neck dilation is often associated with detachment of the stent-graft from the aortic wall, which is followed by the development of a proximal endoleak or stent-graft migration. Fixation of stent-grafts can be improved by placing the proximal stent above one or both of the renal artery orifices. Current experimental and clinical data suggest that renal function is not impaired by suprarenal aortic stents during the first year; however, this finding may not apply to all types of stents. Fixation of stent-grafts also may be improved by using stents with barbs that pierce the aortic wall. Additionally, the force that is exerted on the anchoring device may well be reduced by fully stented grafts with an associated increase in column strength. In the future, the risk of neck dilation and stent-graft dislodgement might also be limited by novel techniques such as laparoscopic banding of the neck or endoluminal stapling devices.
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| 85. |
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| 86. |
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| 87. |
- Malina, Martin, et al.
(författare)
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Late aortic arch perforation by graft-anchoring stent: complication of endovascular thoracic aneurysm exclusion
- 1998
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Ingår i: Journal of Endovascular Surgery. - 1074-6218. ; 5:3, s. 274-277
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: To describe a fatal case of late aortic perforation by an endograft-anchoring stent. METHODS AND RESULTS: A 69-year-old woman presented 2 years after thoracoabdominal aneurysm repair with a 9-cm dilatation of the descending thoracic aorta proximal to the conventional aortic graft. A 38-mm Dacron graft with multiple Gianturco Z-stents sutured inside was placed transluminally across the aortic arch such that part of the uncovered portion of the proximal stent was partially across the left subclavian orifice. Four months later, the patient died from massive hemorrhage. Autopsy showed that the uncovered portion of the proximal stent had perforated the aortic arch. CONCLUSIONS: This case stresses the need for low-profile stent-grafts and smaller, more flexible introducer systems. Anchoring stents must be flexible, less traumatic, and strong enough to create a watertight seal even in tortuous vessels. To avoid aortic arch damage by thoracic stent-grafts, the proximal stent should be fully covered by the fabric.
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| 88. |
- Malina, Martin, et al.
(författare)
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Rupturerat bukaortaaneurysm. Endovaskulär behandling i lokalanestesi
- 2001
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Ingår i: Läkartidningen. - 0023-7205. ; 98:49, s. 5644-5648
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Tidskriftsartikel (refereegranskat)abstract
- We report on endovascular repair of a ruptured abdominal aortic aneurysm. A bifurcated stent graft was inserted under local anesthesia. Aortic clamping is rapidly provided by percutaneous placement of an aortic occlusion balloon catheter. Carbon dioxide can usually replace conventional contrast in patients with renal insufficiency. This minimally invasive procedure may reduce perioperative morbidity and mortality in patients with ruptured aortic aneurysms. The advantages and limitations of this novel technique are discussed.
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| 89. |
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| 90. |
- Mattsson, Patrik, et al.
(författare)
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β-Amyloid binding in elderly subjects with declining or stable episodic memory function measured with PET and [11C]AZD2184
- 2015
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Ingår i: European Journal of Nuclear Medicine and Molecular Imaging. - : Springer. - 1619-7070 .- 1619-7089. ; 42:10, s. 1507-1511
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: Cognitive decline has been suggested as an early marker for later onset of Alzheimer's disease. We therefore explored the relationship between decline in episodic memory and β-amyloid using positron emission tomography (PET) and [11C]AZD2184, a radioligand with potential to detect low levels of amyloid deposits.Methods: Healthy elderly subjects with declining (n = 10) or stable (n = 10) episodic memory over 15 years were recruited from the population-based Betula study and examined with PET. Brain radioactivity was measured after intravenous administration of [11C]AZD2184 The binding potential BP ND was calculated using linear graphical analysis with the cerebellum as reference region.Results: The binding of [11C]AZD2184 in total grey matter was generally low in the declining group, whereas some binding could be observed in the stable group. Mean BP ND was significantly higher in the stable group compared to the declining group (p = 0.019). An observation was that the three subjects with the highest BPND were ApoE ε4 allele carriers.Conclusions: We conclude that cognitive decline in the general population does not seem to stand by itself as an early predictor for amyloid deposits.
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