Detection and prediction of acute heart transplant rejection with the myocardial T2 determination provided by a black-blood magnetic resonance imaging sequence.

OBJECTIVES: This study aimed to determine whether the myocardial T2 relaxation time, determined using a black-blood magnetic resonance imaging (MRI) sequence, could predict acute heart transplant rejection. BACKGROUND: The use of black-blood MRI sequences allows suppression of the confusing influence of blood signal when myocardial T2 is calculated to detect myocardial edema. METHODS: A total of 123 investigations, including cardiac MRI and myocardial biopsy, were performed 8 +/- 11 months after heart transplantation. Myocardial T2 was determined using an original inversion-recovery/spin-echo sequence. RESULTS: A higher than normal T2 (> or = 56 ms) allowed an accurate detection of the moderate acute rejections evidenced at baseline biopsy (> or = International Society for Heart and Lung Transplantation grade 2): sensitivity, 89% and specificity, 70% (p < 0.0001). T2 was increased in grade 2 (n = 11) compared with grade 0 (n = 49, p < 0.05), grade 1A (n = 34, p < 0.05) and grade 1B (n = 21, p < 0.05); T2 was further increased in grade 3 (n = 8) compared with grade 2 (p < 0.05). In addition, in patients without rejection equal to or greater than grade 2 at baseline, a T2 higher than normal (> or = 56 ms) was correlated with the subsequent occurrence of equal or greater than grade 2 rejection within the next three months: sensitivity 63% (12/19) and specificity 78% (64/82) (p = 0.001). CONCLUSIONS: Myocardial T2 determined using a black-blood MRI sequence, is sufficiently sensitive to identify most of the moderate acute rejections documented with biopsy at the same time, but is also a predictor of the subsequent occurrence of such biopsy-defined rejections.

State of the art: which stent for which lesion in peripheral interventions?

Applications of endovascular procedures have been expanded dramatically throughout the human body for both occlusive and aneurysmal disease; arteries at the aortoiliac and femoropopliteal levels are no exception. Currently, interventional procedures are the 1st treatment option for most patients who have peripheral artery disease. Although balloon angioplasty alone offers good immediate and long-term results, the addition of stents has been proposed to improve the procedural success of angioplasty and extend its application to more patients with vascular disease. Stenting, however, is controversial. Its use is considered acceptable in the aortoiliac vessels but is more in dispute for the femoropopliteal vessels. Moreover, the rapid development of endovascular stents for peripheral applications has made stent selection a complicated task for clinical practitioners. Many factors influence the type of stent selected; therefore, knowledge of the stents available--including various designs and individual properties--is mandatory. Appropriate selection depends on adequate preprocedural evaluation of the lesion; the choice of approach; the choice of primary versus selective stent placement; the location and characteristics of the lesion; the availability of stents in the intervention suite; and the experience of the operator Several stents are now available, but they are not equivalent; it is important to select the stent that is best suited to the lesion. On the basis of our experience using different types of stents, as well as our review of the world medical literature, we summarize the properties of various stents and specific indications for their application. This report is intended for use as a practical guide to stent selection.

Percutaneous endovascular treatment of peripheral aneurysms.

BACKGROUND: To evaluate the feasibility and efficacy of percutaneous endovascular treatment of peripheral aneurysms. METHODS: Forty-eight patients, M: 41, F: 7, mean age: 65.7 +/- 10.1 years (47-85 years), with 50 aneurysms were treated: 45 with covered stents (Cragg/Passager 22, Corvita 21, Wallgraft 1, Endotex 1) 4 with non-covered stents and 1 with stent graft. Twenty-six aneurysms located at the iliac artery, 12 at the femoral and 12 at the popliteal artery. Mean lesion length: 61.1 +/- 21.3 mm. Percutaneous approach used in all cases, femoral antegrade (n=24), retrograde (n=23), contralateral (n=2), popliteal (n=1). Stents used were 6-12 mm in diameter and 30-120 mm in length. Multiple stents used to cover all lesions in 20 cases. RESULTS: Immediate technical success was 96% (48/50). In 1 case of long, tortuous femoropopliteal aneurysm, it was impossible to cover the low part, due to rigidity of the device used, in 1 case of large iliac aneurysm there was incomplete immediate exclusion. No complication during the procedure. Four patients developed non-infectious fever/local pain. Eight thromboses occurred: 2 at iliac, 1 at femoral and 5 at the popliteal level. All other stents remained patent, the aneurysms completely excluded over a mean follow-up of 20.6 +/- 13.2 m, maximum 61 m. Primary patency: all lesions 82%, iliac 92%, femoropopliteal 78%. Secondary patency: all lesions 88%, iliac 96%, femoropopliteal 86%. CONCLUSION: Percutaneous endoluminal treatment of peripheral aneurysms seems safe and effective with high technical success and good long-term results, except for popliteal localization. It could be an alternative to surgery.

Percutaneous transluminal angioplasty of the subclavian arteries.

PURPOSE: To review the feasibility, risks, and long-term results of subclavian artery angioplasty with and without Palmaz stent placement. METHODS: Over a 9-year period, 113 patients (67 males; mean age 63 +/- 13 years) underwent percutaneous balloon angioplasty of subclavian occlusive lesions for a variety of indications: vertebrobasilar insufficiency (n = 70), upper limb ischemia (n = 50), coronary steal syndrome (n = 6), or anticipated coronary artery bypass grafting using the internal mammary artery in 12 asymptomatic patients. There were 94 (83%) stenoses and 19 (17%) occlusions with a mean percent stenosis of 80.1% +/- 7.4% (range 70 to 100). Mean lesion length was 24 +/- 8 mm (range 10 to 50). Beginning in 1989, stents were implanted for suboptimal dilation; in 1995, stenting became routine. RESULTS: Overall, 103 (91%) of 113 lesions were successfully treated; 10 (53%) occlusions could not be recanalized. Fifty-one stents were implanted in 46 patients. There were 3 (2.6%) procedural complications: a transient ischemic attack, one major (fatal) stroke, and an arterial thrombosis 24 hours after the procedure (treated medically) (0.9% major stroke and death rate). During a mean 4.3-year follow-up (range to 10), 16 (15.5%) restenoses were treated with angioplasty (n = 4), stenting (n = 7), or surgery (n = 5). Primary and secondary patencies for all treated lesions (n = 113) at 8 years were 75% and 81%, respectively; in patients without initial stent placement, the rates were 69% and 76%, while in those with stents, the rates rose slightly to 87% and 94% at 2.5 years (NS). Patency rates for all 103 recanalized lesions were 83% and 90% at 8 years (81% and 90% without stent and 87% and 94% with stent at 2.5 years, respectively [NS]). CONCLUSIONS: Balloon angioplasty with or without stenting is safe and effective for treating subclavian artery occlusive diseases with good long-term patency. Recanalization of occlusions is more difficult to achieve. Stents (implanted only for suboptimal dilation) do not seem to improve long-term patency.

Stents in the treatment of renal artery stenosis: long-term follow-up.

PURPOSE: To evaluate the role of percutaneous stenting in the treatment of renal arterial lesions after failure of balloon angioplasty. METHODS: Two hundred ten patients (139 males; mean age 67.7 +/- 9.9 years, range 27 to 87) had 259 balloon-expandable stents (165 Palmaz and 94 Renal Bridge stents) implanted in 244 renal artery stenoses (171 ostial and 73 nonostial lesions). The patients were suffering from intractable hypertension (n = 210) and/or renal dysfunction (n = 48). The majority of the lesions (n = 234) were atheromatous in origin. Stents were implanted for suboptimal balloon dilation (n = 182, 75%), restenotic lesions (n = 27, 11%), or dissection (n = 9, 4%); 26 (11%) ostial lesions were stented primarily. Mean lesion length was 11.9 +/- 4.4 mm (range 5 to 30) and mean percent stenosis was 81.9% +/- 8.25% (range 70 to 100). RESULTS: Immediate technical success was 99% (241 of 244). Three (1.2%) major complications included one intraprocedural stent thrombosis, one arterial perforation manifesting as a perirenal hematoma 24 hours after the procedure, and one renal arterial rupture. Follow-up over a mean 25.4 +/- 22.8 months (range 1 to 96) in 185 eligible patients (209 arteries) found 24 cases of restenosis (11.4%). Primary and secondary patencies for all lesions at 60 months were 79% and 98%, respectively, with no significant differences between ostial and nonostial lesions or stent types. Hypertension was reversed in 35 (19%), improved in 112 (61%), and remained unchanged in 37 (20%). Renal function was improved in 29% (14 of 48), unchanged in 67% (32 of 48), and worse in 4% (2 of 48). CONCLUSIONS: Renal artery stenting is safe, effective, and may be an alternative to surgery, particularly in ostial lesions. Our experience shows reduction in the restenosis rate compared to conventional angioplasty. All ostial stenoses should be stented.

Angioplasty and stenting of the extracranial carotid arteries.

PURPOSE: To study the feasibility and safety of stent-supported angioplasty in the treatment of atherosclerotic stenoses of the extracranial carotid arteries. METHODS: Carotid angioplasty was attempted in 174 arteries (163 patients: 126 males; mean age: 71 +/- 10 years, range 47 to 93). Mean lesion length was 15.1 +/- 4.1 mm, and mean percent stenosis was 83.8% +/- 7.3% (reference diameter 5.8 +/- 0.7 mm). The majority (106, 65%) were asymptomatic (51% of all patients had severe coronary disease, 32% had peripheral vascular diseases). Patients underwent independent neurological examination, computed tomography, duplex ultrasonography, and angiography preprocedurally, 24 hours after the procedure, and at 6-month follow-up intervals. Most (142, 82%) carotid arteries were treated without cerebral protection, but a protective triple coaxial catheter was used in 32 (18%) patients. Stents (primarily Palmaz and Wallstent) were deployed routinely in all cases; 18% were implanted without predilation. RESULTS: Immediate technical success was 173 of 174 (99.4%) (1 access failure referred electively to surgery). Eight (4.6%) neurological complications occurred in the periprocedural period: 3 transient ischemic attacks, 2 minor strokes, and 3 major strokes (1 amaurosis and 2 hemiplegias). Two major complications developed despite cerebral protection. There were no deaths or myocardial infarctions and only 3 cervical access site hematomas. Over a mean 12.7 +/- 9.2 month follow-up (range 1 to 36), no ipsilateral neurological complications have been seen. There were 4 (2.3%) restenoses (3 redilated, 1 treated medically) and 1 mild Palmaz stent compression, all found within the first 6 months. Primary and secondary patencies at 3 years are 96% and 99%, respectively. CONCLUSIONS: Angioplasty with routine stenting seems feasible and safe for treating certain types of carotid stenoses even in high-surgical risk patients; however, randomized trials are necessary before this treatment can be offered as an alternative to endarterectomy.

Endovascular treatment of internal iliac artery aneurysms.

PURPOSE: To describe a technique for percutaneous endovascular repair of internal iliac artery aneurysms. TECHNIQUE: In a patient with an isolated internal iliac artery aneurysm and combined tight stenoses at the origins of the external and internal iliac arteries, interventional treatment consisted of coil embolization of the internal iliac artery and branches using the contralateral femoral approach. Balloon dilation of the external iliac stenosis occluded the internal iliac artery, and Palmaz stents were placed in the external iliac stenosis to overcome residual luminal narrowing. CONCLUSIONS: This one-step percutaneous technique allows total exclusion of the internal iliac artery aneurysm using coil embolization. This treatment may be an alternative to surgery in isolated internal iliac artery aneurysms with small orifices.

Percutaneous endoluminal treatment of iliac occlusions: long-term follow-up in 105 patients.

PURPOSE: To evaluate the long-term results of percutaneous recanalization techniques in occluded iliac arteries. METHODS: Percutaneous recanalization was attempted in 105 patients (97 men; mean age 56 years, range 34 to 80) with iliac occlusions using thrombolysis (n = 15), excimer laser (n = 4), mechanical thrombectomy (n = 16), balloon angioplasty alone (n = 23), and angioplasty plus stenting (n = 69). The majority of lesions (n = 72) were in the common iliac artery (CIA); 33 were in the external iliac artery (EIA). RESULTS: The primary recanalization rate was 88% (92/105) independent of location (EIA: 90%, CIA: 86%) and lesion length, but dependent on age of thrombus (< 3 months: 100%, > 3 months: 79%, p < 0.02). Complications included 5 (4.8%) cases of distal embolism treated by thromboaspiration or Fogarty balloon embolectomy. Seven (6.7%) early thromboses were treated surgically. Primary and secondary patency rates were calculated at 6 years for all 105 cases and for the 92 recanalized lesions using life-table analysis. Overall, primary patency was 52% (CIA: 58%, EIA: 34%) and secondary 66% (CIA: 74%, EIA: 40%). Lesions < 6 cm had a primary patency of 70%, while those > 6 cm had a 31% rate (p < 0.01). Secondary patencies were 86% and 42%, respectively (p < 0.01). Among recanalized lesions, the primary patency was 61% (CIA: 69%, EIA: 38%) and secondary 77% (CIA: 88%, EIA: 45%; p < 0.05). Lesions < 6 cm had a primary patency rate of 72%, while longer lesions had a primary rate of 44% (p < 0.04); secondary patencies were 89% and 59%, respectively (NS). Primary patency without stent was 57% and with stent 65% (NS); secondary patency without stent was 71% and with stent 82% (NS). CONCLUSIONS: Percutaneous recanalization of iliac occlusions represents a true alternative to vascular surgery and a first-line treatment option. Stents have a tendency to improve long-term results and are recommended for routine use in chronic iliac occlusions.