COMPARE: prospective, randomized, non-inferiority trial of high- vs. low-dose paclitaxel drug-coated balloons for femoropopliteal interventions.

AIMS: Drug-coated balloons (DCBs) for femoropopliteal interventions have not been tested against each other. We aimed to directly compare efficacy and safety of a high-dose (In.Pact™) vs. low-dose (Ranger™) DCB with nominal paclitaxel densities of 3.5 vs. 2.0 µg/mm2. METHODS AND RESULTS: Within a prospective, multicentre, non-inferiority, clinical trial 414 patients with symptomatic femoropopliteal lesions (Rutherford classification 2-4) were randomly assigned in a 1:1 ratio to endovascular treatment with either high- or low-dose DCB after stratification for lesion length. Primary efficacy and safety endpoints comprised primary patency and freedom from major adverse events (i.e. device and procedure-related deaths through 1 month, major amputations, and clinically driven target lesion revascularization through 12 months). We set a non-inferiority margin of -10% at 12 months. Total occlusions were observed frequently (>40%) and provisional stenting was performed in every fourth intervention. Non-inferiority was determined for both primary efficacy and safety endpoints at 12 months. Primary patency was 81.5% in the high-dose and 83.0% in low-dose DCB group {difference: 1.5% [lower bound of the 90% two-sided confidence interval (CI) -5.2%]; Pnon-inferiority < 0.01}. Freedom from major adverse events was determined in 92.6% in high-dose and in 91.0% in low-dose DCB group [difference -1.6% (lower bound of the 90% two-sided CI -6.5%); Pnon-inferiority < 0.01]. Overall death rate was low (2.0%) and no major amputation occurred. CONCLUSION: Two DCBs with different coating characteristics exhibited comparable results with excellent effectiveness and safety through 12 months for femoropopliteal interventions including a wide range of lesion lengths. CLINICAL TRIAL REGISTRATION: The trial is registered with ClinicalTrials.gov (NCT02701543).

Drug-coated Balloon Angioplasty of Femoropopliteal Lesions Maintained Superior Efficacy over Conventional Balloon: 2-year Results of the Randomized EffPac Trial.

Background Paclitaxel drug-coated balloon (DCB) catheter angioplasty is the preferred treatment for revascularization of femoropopliteal lesions in peripheral artery disease, but mortality is a safety concern. Purpose To assess 2-year efficacy and safety of DCB angioplasty compared with conventional balloon angioplasty (also known as plain old balloon angioplasty or POBA). Materials and Methods This prospective, multicenter, randomized controlled trial enrolled consecutive participants with symptomatic superficial femoral and/or popliteal artery disease at 11 German centers between September 2015 and December 2016. Participants underwent DCB angioplasty or conventional balloon angioplasty. Primary outcome of 6-month late lumen loss showed superiority of DCB angioplasty over conventional balloon angioplasty. Evaluation at 2 years included secondary outcomes of primary patency and target lesion revascularization (TLR) estimated with Kaplan-Meier analysis, clinical and hemodynamic improvement, quality of life, target limb amputation, and all-cause mortality. Results A total of 171 participants (mean age, 69 years ± 8; 111 men) were evaluated. At 2 years, primary patency was achieved in 90.2% (95% confidence interval [CI]: 80.4%, 95.2%) of DCB angioplasty and 62.7% (95% CI: 50.0%, 73.0%) of conventional balloon angioplasty participants (P < .001). Freedom from TLR occurred in 97.2% (95% CI: 89.1%, 99.3%) of DCB angioplasty and 78% (95% CI: 66.5%, 86.0%) of conventional balloon angioplasty participants (P = .001). The groups did not differ in sustained improvement from baseline to 2 years in Rutherford-Becker category (row mean scores difference, 1.7; P = .19) and showed no difference in mean improvement in the Walking Impairment Questionnaire score (-0.8%; 95% CI: -11.8%, 10.2%; P = .88), EuroQol Group's five-dimension index of quality of life (-0.06; 95% CI: -0.17, 0.03; P = .20), or ankle-brachial index (0.03; 95% CI: -0.08, 0.14; P = .57). No major amputation was necessary. One DCB angioplasty and two conventional balloon angioplasty participants died (risk ratio, 0.48; 95% CI: 0.04, 5.10). Conclusion At 2 years after paclitaxel drug-coated balloon (DCB) angioplasty, primary patency and freedom from target lesion revascularization remained superior compared with conventional balloon angioplasty. DCB angioplasty resulted in sustained clinical and hemodynamic improvement with no increased risk of mortality. © RSNA, 2020 Online supplemental material in available for this article.

Optimized drug-coated balloon angioplasty of the superficial femoral and proximal popliteal arteries using the Tack Endovascular System: TOBA III 12-month results.

OBJECTIVE: The Tack Endovascular System (Intact Vascular, Wayne, Pa) combines low-metallic content with focal delivery to seal areas of dissection associated with balloon angioplasty. The device system is designed to treat vascular dissections in the superficial femoral and proximal popliteal arteries. Tack implants exert low radial force and are associated with minimal metal burden, which reduces the mechanical stress on the arterial wall in treating dissections after balloon angioplasty. This study investigated the safety and effectiveness of the Tack Endovascular System in patients with dissections after drug-coated balloon (DCB) angioplasty. METHODS: The Tack Optimized Balloon Angioplasty III (TOBA III) study is a prospective, multicenter, single-arm study in which patients who underwent percutaneous transluminal angioplasty with the Medtronic IN.PACT Admiral DCB (Medtronic, Dublin, Ireland) and experienced dissection after angioplasty were treated with Tack implants. The primary end points were freedom from major adverse events at 30 days and primary patency at 12 months. RESULTS: A total of 201 patients were enrolled in the trial, 169 with standard-length lesions (≥20 mm and ≤150 mm) and 32 with long-length lesions (>150 mm and ≤250 mm). Safety and effectiveness results were favorable compared with historical benchmarks at 12 months in the standard-lesion cohort. Notably, patients in the standard-lesion cohort experienced 95.0% primary patency, 97.5% freedom from clinically driven target lesion revascularization, 100% freedom from amputation, and 100% survival at 12 months (P < .0001). Primary patency in long-lesion patients was 89.3%, freedom from clinically driven target lesion revascularization was 96.8%, and freedom from amputation was 100% at 12 months. Device success was achieved in 95.8% (182/190) and 97.7% (43/44) of devices deployed into standard-lesion and long-lesion patients, respectively. Procedural success was 99.4% (168/169) and 100% (44/44) in the standard-lesion and long-lesion cohorts, respectively, with only one bailout stent placed in the entire population. CONCLUSIONS: The Tack Endovascular System is a safe and effective treatment option for patients with dissections after angioplasty in the superficial femoral and proximal popliteal arteries, with high patency, low rates of secondary intervention, and low incidence of bailout stenting when it is used in combination with DCB.

Six-Month Outcomes From the First-in-Human, Single-Arm SELUTION Sustained-Limus-Release Drug-Eluting Balloon Trial in Femoropopliteal Lesions.

Purpose: To evaluate the safety and efficacy of the novel SELUTION sustained-limus-release (SLR) drug-eluting balloon (DEB) in the treatment of femoropopliteal lesions. Materials and Methods: Between October 2016 and May 2017, 50 subjects (mean age 69.6±10.4 years; 29 men) with symptomatic moderate to severe lower limb ischemia (Rutherford categories 2 or 3) were enrolled at 4 German centers for the SELUTION SLR first-in-human trial (ClinicalTrials.gov NCT02941224). The SELUTION SLR utilizes micro-reservoirs (biodegradable polymer spheres containing sirolimus) embedded within an amphipathic membrane coated onto an angioplasty balloon. The biodegradable reservoirs are transferred to the target vessel lumen during brief balloon inflation. The primary trial objective was comparison of angiographic late lumen loss at 6 months against an objective performance criterion (OPC) value of 1.04 mm for uncoated balloon angioplasty. Secondary endpoints included device, procedural, and clinical success; clinical and imaging assessments of primary patency and restenosis; functional assessments including Rutherford category and ankle-brachial index (ABI); and major adverse events [composite of cardiovascular mortality, index limb amputation, target limb thrombosis, and clinically-driven target lesion revascularization (CD-TLR)]. Results: At 6 months, median angiographic late lumen loss following SELUTION SLR treatment was 0.19 mm (range -1.16 to 3.07). Mean angiographic late lumen loss (n=34) was 0.29±0.84 mm (95% CI -0.01 to 0.58), significantly lower than the 1.04-mm OPC value (p<0.001). The rate of primary patency by duplex ultrasound was 88.4%, and freedom from angiographic binary restenosis was 91.2%. Through 6 months, there was significant improvement over baseline in Rutherford categories (p<0.001) and in ABI measurements (p<0.001). A single case (2%) of CD-TLR occurred at 5 months. There were no other major adverse events. Conclusion: Through 6 months, the SELUTION SLR DEB appears to inhibit restenosis effectively and safely, improving outcomes in subjects with symptomatic femoropopliteal disease.

Paclitaxel-Coated Balloon vs Uncoated Balloon Angioplasty for Treatment of In-Stent Restenosis in the Superficial Femoral and Popliteal Arteries: The COPA CABANA Trial.

Purpose: To investigate the efficacy and sustainability of drug-coated balloon (DCB) treatment of femoropopliteal in-stent restenosis (ISR). Materials and Methods: An investigator-initiated, prospective, multicenter, 1:1 randomized study enrolled 88 patients for treatment of ISR with DCB (n=47; mean age 68.3±9.6 years; 26 men) or uncoated balloon (n=41; mean age 67.6±10.2 years; 26 men) angioplasty (ClinicalTrials.gov identifier NCT01594684). Additionally, the protocol provided for an observational arm composed of patients from either randomized arm who experienced recurrent ISR ≥30 days after the index treatment. Redo treatment consisted of 2 DCBs sequentially inflated at the same location (double dose therapy). The majority of patients (66, 78%) had Rutherford category 3 ischemia. The mean lesion length was 140 mm; a third (27, 31%) were total occlusions. The primary endpoint was angiographic late lumen loss (LLL) at 6 months evaluated by an independent core laboratory. Results: Twenty-two patients (7 DCB +15 uncoated) were treated for recurrence with fully overlapping double DCB angioplasty. Six-month LLL was lower after DCB (0.34±1.12 mm) treatment than after angioplasty with an uncoated balloon (1.58±1.10 mm, p<0.001). At the 12-month follow-up, target lesion revascularization (TLR) was performed in 18 (49%) of 37 patients in the uncoated group, 6 (14%) of 43 patients in the single-dose DCB group (p=0.001), and no patients from the recurrent ISR group. At ~2 years after treatment, a remarkable number (14/27, 52%) of TLRs were recorded in the single-dose DCB group. Conclusion: Treatment with DCBs resulted in significantly less 6-month LLL and fewer TLRs up to 24 months than treatment with uncoated balloons. The double dose for treating recurrent ISR did not cause recognizable adverse events or require TLR up to 24 months.

Heparin-bonded stent-graft for the treatment of TASC II C and D femoropopliteal lesions: the Viabahn-25 cm trial.

Purpose: To confirm the performance and safety of the 25-cm Viabahn endoprosthesis with Propaten bioactive surface when used in the treatment of de novo and/or restenotic TransAtlantic Inter-Society Consensus II C and D lesions of the superficial femoral artery and proximal popliteal artery. Methods: The 25-cm Gore Viabahn Endoprosthesis study (ClinicalTrials.gov identifier NCT01263665) is a prospective, multicenter, single-arm study that enrolled 71 patients (50 men; mean age 66.7 ± 8.34 years) with lifestyle-limiting claudication (Rutherford class 2 to 4) and lesions longer than 20 cm (mean length 26.5 ± 5.31 cm, range 20-40). The majority of lesions (92.9%) were total occlusions. The primary performance outcome was post-deployment stent length within ± 10% of the pre-deployment stent length determined angiographically by quantitative vascular analysis. The primary safety outcome was device- and procedure-related serious adverse events occurring within 30 days of the procedure. The patients underwent follow-up examinations at 1 month and 1 year. Results : The median follow-up was 12.3 months (mean 12.3 ± 0.6). Nine (12.7%) patients discontinued the study due to different reasons including 2 bypass surgeries. Angiography was available in 60 patients to determine the primary performance outcome, which was met in all cases. Two (2.8%) patients experienced a procedure-/device-related adverse event (dissection) during the 30-day follow-up. Kaplan-Meier estimates for 1-year primary and secondary patency were 67.0% [95% confidence interval (CI) 53.5% to 77.3%] and 96.9% (95% CI 88.0% to 99.2%), respectively. Changes in ankle-brachial index and Rutherford category at 1 and 12 months each showed sustained improvement. Conclusion : This study confirms that the 25-cm Viabahn endoprosthesis acutely performs as intended and is safe when used as indicated in complex femoropopliteal lesions. One-year primary and secondary patency rates are satisfying and comparable to historical prosthetic bypass graft outcomes.

High-grade, non-flow-limiting dissections do not negatively impact long-term outcome after paclitaxel-coated balloon angioplasty: an additional analysis from the THUNDER study.

PURPOSE: To investigate the impact of using paclitaxel-coated balloons (PCB) on outcome after post-angioplasty dissection in femoropopliteal arteries. METHODS: The angiograms obtained in the THUNDER study (ClinicalTrials.gov identifier NCT00156624) were analyzed to compare degrees of dissection and angiographic parameters between the control (uncoated balloons, n=43) and treatment (PCBs, n=43) groups before and after the intervention and at 6-month follow-up. Furthermore, target lesion revascularizations (TLR) were documented up to 2 years. RESULTS: In each group, 24 (56%) patients had a dissection after the intervention. At the 6-month follow-up, patients with dissection of any grade after treatment with PCBs had significantly less late lumen loss (0.4 mm) than patients with dissection after treatment with uncoated balloons (1.9 mm, p=0.001) and a lower degree of stenosis (20% vs. 51%, respectively; p=0.003). Patients with severe dissection (grades C, D, or E) especially seemed to benefit from the PCBs, with late lumen loss of 0.4 mm vs. 2.4 mm for controls (p=0.05). The binary restenosis rate was also markedly lower in the PCB group (20%) than in the uncoated group (55%, p=0.02). In the 2-year follow-up, TLR was performed in 56% of patients in the control group compared to 10% of patients in the PCB group (p=0.002). CONCLUSION: The results of this subgroup analysis suggest that patients with dissection following treatment with a paclitaxel-coated balloon have a very acceptable outcome and stent implantation is not necessary as long as the dissection does not result in acute flow limitation.

Clinical investigation of the GORE drug-coated PTA balloon catheter for CE mark approval.

OBJECTIVES: Paclitaxel-coated balloon angioplasty has been established as the first-line therapy for femoropopliteal artery disease. The primary objectives of the study were to evaluate the performance and the safety of the GORE-DCB Catheter in the treatment of atherosclerotic femoropopliteal lesions in patients with peripheral artery disease for CE-Mark approval. METHODS: Prospective, single-arm, multicenter study with 24 months follow-up. The GORE-DCB Catheter consists of a drug-coated nylon (inner layer)/ePTFE (outer layer) composite balloon. The ePTFE layer is coated with paclitaxel (concentration: 3.5 µg/mm2) and the excipient stearic acid/tromethamine (tris). The primary endpoints were 6-month late lumen loss (LLL) and 30-day of freedom from Major Adverse Events (MAE). RESULTS: Fifty-two subjects were enrolled, 69% men, median age 69 (49-83) years. Acute device success was 100%, the 30-day MAE rate was zero. Study primary endpoint of LLL (-0.17 mm) showed significant superiority compared to the performance goal of uncoated PTA balloon catheters from literature. At 1 and 2 years, primary patency rates were 81.8% and 68.7%, respectively, and freedom from clinically driven target lesion revascularization rates was 87.9% and 83.4%, respectively. CONCLUSION: The study demonstrates that the treatment of lesions in femoropopliteal arteries with the GORE-DCB Catheter is safe and effective.

Low-Dose vs High-Dose Paclitaxel-Coated Balloons for Femoropopliteal Lesions: 2-Year Results From the COMPARE Trial.

BACKGROUND: So far only 1-year data have been reported for direct comparisons of paclitaxel-coated balloons (PCBs) using different coating technologies. OBJECTIVES: The aim of this study was to report the 24-month results on the efficacy and safety of low-dose vs high-dose PCBs with nominal paclitaxel densities of 2.0 and 3.5 µg/mm2 and different coating technologies for femoropopliteal interventions from the COMPARE (Compare I Pilot Study for the Treatment of Subjects With Symptomatic Femoropopliteal Artery Disease) trial. Procedural characteristics of clinically driven (CD) target lesion revascularization (TLR) were analyzed. METHODS: Within a prospective, multicenter, clinical trial, 414 patients with symptomatic femoropopliteal lesions (Rutherford categories 2-4, maximum lesion length 30 cm) were randomly assigned in a 1:1 ratio to endovascular treatment with either a low-dose (Ranger) or a high-dose (IN.PACT) PCB after stratification for lesion length. Two-year follow-up included assessment of primary patency (defined as absence of CD TLR or binary restenosis with a peak systolic velocity ratio >2.4 by duplex ultrasound), safety, and functional and clinical outcomes. RESULTS: At 2 years, the Kaplan-Meier estimates of primary patency were 70.6% and 71.4% for the low-dose and high-dose PCBs (log-rank P = 0.96), respectively. One major amputation occurred in the high-dose group, and rates of all-cause mortality (3.6% vs 2.2%; P = 0.55) and CD TLR (17.3% vs 13.0%; P = 0.31) were similar between the groups. Among a total of 57 CD TLRs, 44.6% were performed for reocclusion and 28.1% for in-stent restenosis. Functional and clinical benefits over baseline were sustained in both groups. CONCLUSIONS: The 2-year results of the COMPARE trial demonstrate a sustained treatment benefit of both low-dose and high-dose PCBs for femoropopliteal interventions including a wide range of lesion lengths. (Compare I Pilot Study for the Treatment of Subjects With Symptomatic Femoropopliteal Artery Disease; NCT02701543).

Long-Term Effectiveness and Safety of Femoropopliteal Drug-Coated Balloon Angioplasty : 5-Year Results of the Randomized Controlled EffPac Trial.

PURPOSE: This study aimed to assess 5-year effectiveness and safety of femoropopliteal angioplasty with the Luminor® 35 drug-coated balloon (DCB). MATERIALS AND METHODS: The EffPac trial was a prospective, multicenter, randomized controlled trial that enrolled 171 patients of Rutherford category 2 to 4 with medium length femoropopliteal lesions. Patients were allocated 1:1 to either Luminor® 35 DCB angioplasty or plain old balloon angioplasty (POBA). Assessment at 5 years included primary patency, freedom from clinically driven target lesion revascularization (CD-TLR), clinical improvement, and target limb amputation. Long-term vital status was ascertained in 97.1% of the participants. RESULTS: Kaplan-Meier curves at 5 years demonstrate a primary patency of 61.4% after DCB angioplasty and 53.5% after POBA (log-rank p = 0.040) with a decreasing difference throughout the observation period. Freedom from TLR was 82.1% and 73.7%, respectively (log-rank p = 0.050). Incidence of primary clinical improvement was similar between groups (61% DCB vs. 64% POBA, p = 0.94). Major target limb amputation was necessary in one POBA-group participant. Freedom from all-cause death at 5 years was 88.5% after DCB and 86.0% after POBA (log-rank p = 0.34). CONCLUSIONS: Primary patency after femoropopliteal DCB angioplasty remained superior to POBA throughout 5 years, however, with decreasing difference. Clinical improvement, freedom from TLR, and all-cause mortality were similar between groups over the long term. (Effectiveness of Paclitaxel-Coated Luminor® Balloon Catheter Versus Uncoated Balloon Catheter in the Superficial Femoral Artery [EffPac]; NCT02540018).

Efficacy and safety of a novel paclitaxel-nano-coated balloon for femoropopliteal angioplasty: one-year results of the EffPac trial.

AIMS: Although paclitaxel drug-coated balloon (DCB) angioplasty is an established endovascular treatment for peripheral artery disease, restenosis remains a major concern. Thus, we compared a novel paclitaxel-coated DCB with nano-coating technology with uncoated plain old balloon angioplasty (POBA). METHODS AND RESULTS: This multicentre trial randomly assigned 171 patients with stenotic and occlusive lesions of the femoropopliteal artery to angioplasty with a novel DCB or uncoated POBA. The primary endpoint, late lumen loss at six months, was 0.92 mm lower in the DCB group (95% CI: -1.36 to -0.49 mm, p<0.001). Patients showed improved walking after DCB treatment at six months (p=0.021). In the DCB group, 44.6% and 50% of the patients improved by three Rutherford-Becker classification stages after six to 12 months, respectively (POBA: 27.8% and 36.8%, respectively). Only one patient needed TLR (1.3%) in the DCB group, compared to 14 patients (18.7%) in the POBA group after 12 months (relative risk [RR]=0.08, 95% CI: 0.01-0.53, p<0.001). Primary patency was 90.3% (DCB group) versus 65.3% (POBA group) after 12 months (RR=1.38, 95% CI: 1.14-1.67, p<0.001). CONCLUSIONS: The novel DCB was effective and safe for inhibiting restenosis. Moreover, it demonstrated a better improvement in walking than POBA and showed no mortality concerns due to paclitaxel application after 12 months. Clinical Trials Identifier: NCT02540018

Angioplasty of femoral-popliteal arteries with drug-coated balloons: 5-year follow-up of the THUNDER trial.

OBJECTIVES: The purpose of this study was to evaluate the 5-year follow-up (FU) data of the THUNDER (Local Taxan With Short Time Contact for Reduction of Restenosis in Distal Arteries). BACKGROUND: The THUNDER trial was the first study to investigate the treatment of femoropopliteal arteries with a paclitaxel-coated balloon (PCB). METHODS: In 154 patients, femoropopliteal arteries were treated with PCB, with angioplasty with paclitaxel in contrast medium, or no paclitaxel (control). The primary endpoint was 6-month late lumen loss (LLL). Secondary endpoints included freedom from target lesion revascularization (TLR), binary restenosis rate, and amputation. The 5-year FU compares outcomes in patients treated with PCB and control subjects. Additionally, LLL at 6 months and TLR up to 5-year FU were analyzed in terms of sex and lesion length. RESULTS: Over the 5-year period, the cumulative number of patients with TLR remained significantly lower in the PCB group (21%) than in the control group (56%, p = 0.0005). In the small group of patients with angiographic and duplex sonographic follow-up, PCB was associated with a lower rate of binary restenosis (17% vs. 54%; p = 0.04). No signs of aneurysm formation or constrictive fibrosis were detected. Whereas LLL at 6-month FU did not differ between men and women in the PCB group, the TLR rate was lower in men than in women at 5-year FU. A benefit of PCB treatment in terms of LLL and TLR was seen independent of lesion length. CONCLUSIONS: The reduced TLR rate following PCB treatment was maintained over the 5-year FU period. No signs of drug-related local vessel abnormalities were detected. (Thunder Trial-Local Taxan With Short Time Contact for Reduction of Restenosis in Distal Arteries [THUNDER]; NCT00156624).

Treatment of femoropopliteal in-stent restenosis with paclitaxel-eluting stents.

OBJECTIVES: This study sought to evaluate the outcomes of drug-eluting stent treatment for femoropopliteal in-stent restenosis (ISR). BACKGROUND: ISR after femoropopliteal interventions is an increasing problem. Although the role of drug-eluting stents in the treatment of coronary ISR is well defined, no published studies have examined drug-eluting stents in the treatment of femoropopliteal ISR. METHODS: This study examines 108 patients with 119 ISR lesions who were enrolled in the ZILVER-PTX single-arm study, a prospective, multicenter clinical trial of 787 patients. All patients were treated with paclitaxel-eluting nitinol stents. RESULTS: Mean patient age was 68.3 ± 9.4 years; 61.1% of patients were men. Mean lesion length was 133.0 ± 91.7 mm; 33.6% of lesions were >150 mm long and 31.1% of lesions were totally occluded. Procedural success was achieved in 98.2% of lesions with 2.1 ± 1.2 stents placed per lesion. Primary patency was 95.7% at 6 months and 78.8% at 1 year. Freedom from target lesion revascularization was 96.2% at 6 months, 81.0% at 1 year, and 60.8% at 2 years. Forty patients experienced major adverse events, exclusively target lesion revascularization. Before treatment, 81.1% of patients had Rutherford scores ≥3; at 2 years, 60.9% of patients had Rutherford scores ≤1. Both ankle brachial index and walking impairment questionnaire scores significantly improved following treatment. The 1-year fracture rate of stents used in ISR lesions was 1.2%. No significant risk factors associated with loss of patency were identified. CONCLUSIONS: Treatment of femoropopliteal ISR with paclitaxel-eluting stents results in favorable acute, midterm, and long-term outcomes. (Zilver PTX Global Registry [ZILVER-PTX]; NCT01094678).

CT angiography of various superficial femoral artery stents: an in vitro phantom study.

PURPOSE: To evaluate CT reconstruction parameters to improve stent lumen visualization in vitro. MATERIAL AND METHODS: 12 latest superficial femoral artery (SFA) stents were placed in a vessel phantom (diameter 4.7 mm, intravascular attenuation 250 HU, extravascular density 50 HU). Stents were imaged with a 128-slice scanner (SOMATOM Definition Flash, Siemens, Germany) with standard parameters: 120 kV, 200 mAs, collimation 128mm × 0.6mm. Different reconstruction parameters were evaluated: B26f, B30f, B45f, B46f and B60f kernel; slice thickness of 0.6, 2.0 and 5.0mm. To measure visualization characteristics, stent lumen diameter and intraluminal attenuation were assessed. RESULTS: Best stent lumen visualization could be obtained using the B46f kernel (p<0.001). The visible stent lumen ranged from 66.4% to 83.3% with a mean diameter of 77.7 ± 4.6%. Nitinol stents showed a significant improved lumen visibility compared to the cobalt-chromium stent (p = 0.02). The most realistic lumen attenuation was achieved using the B46f kernel with a mean attenuation of 259.3 ± 8.9 HU. The visible lumen diameter in protocols with 5mm slice thickness was significantly lower (70.0 ± 4.9%) compared to thinner slices (p<0.001). CONCLUSION: CTA of SFA stents should be reconstructed with a slice thickness of 2.0mm and a B46f kernel to achieve best image quality and to become more sensitive to exclude instent restenosis.

[A case of acute and intense thoracic pain during a dental treatment]. / Akuter thorakaler Vernichtungsschmerz bei einem Zahnarztbesuch.

HISTORY AND ADMISSION FINDINGS: We report on a patient with known hypertension, who presented to his general practitioner with severe thoracic pain of sudden onset. The aches had started during a dental treatment. Immediately, the patient was admitted to hospital by the general practitioner because myocardial ischemia was suspected. INVESTIGATIONS: Neither the electrocardiogram nor the laboratory findings (creatin kinase, troponin I) argued for an acute coronary syndrome. Since the plasma D-dimer level was increased and the transthoracic echocardiography showed discrete signs of right ventricular strain, pulmonary embolism could not be ruled out. Because of the high intensity of pain and for further diagnostics the patient underwent a contrast medium-enhanced computed tomography (CT). DIAGNOSIS, TREATMENT AND COURSE: The contrast medium-enhanced CT showed a type B acute aortic dissection. According to the current guidelines for the treatment of type B aortic dissection, a conservative therapeutic regimen was applied. Antihypertensive therapy was escalated. Furthermore, the patient transiently received analgesic drugs. After three weeks the patient was released from hospital without pain and with physiologic blood pressure under intensified antihypertensive therapy. A follow up examination three months after the acute aortic dissection showed a constant aortic diameter. Therefore, surgical treatment was not indicated. CONCLUSIONS: This case report illustrates a typical clinical picture of acute aortic dissection and gives an overview about its epidemiology, classification, pathogenesis, and prognosis. Furthermore, the diagnostic opportunities and the current guidelines for the treatment of acute aortic dissection are discussed.