Editor's Choice -- Type IIIb Endoleaks: Fabric Perforations of Explanted New Generation Endoprostheses.

OBJECTIVE: To analyse explanted endografts (EGs) and describe fabric degradation responsible for type IIIb endoleaks. METHODS: As part of the European collaborative retrieval programme, 32 EGs with fabric defects on macroscopic evaluation were selected. The explanted EGs were processed and studied based on the ISO 9001 certified standard protocol. It includes instructions on the collection, transportation, cleaning, and examination of explanted material. The precise analysis was performed with a digital microscope of 20 - 200 times magnification. Possible perforation mechanisms were assessed in stress tests. RESULTS: The median time to explantation of the 32 EGs was 54 months. The explants included 65 separate EG modules, with 46 (70.8%) having a combined 388 fabric perforations. Each EG had a median of 4.79 mm2 (interquartile range [IQR] 9.86 mm2) of cumulated hole area (an average of 0.13% of an EG's area). There were 239 (61.6%) expanded polytetrafluoroethylene (ePTFE; 11 EGs) and 149 (38.4%) polyethylene terephthalate (PET; 21 EGs) fabric ruptures, with no difference in hole distribution between these types of material. Overall, 126 (32.5%) stent related and 262 (67.5%) non-stent related fabric perforations were identified. Perforations caused by fabric fatigue in ePTFE (151, 63.2%) and material kinking in PET (41, 27.5%) were the most common. The stent related perforations were larger in size (0.80 mm2) than non-stent related perforations (0.19 mm2); p < .001. Wider interstent spaces and prolonged implantation duration were associated with an increased risk of stent related perforation development; p < .001 and p = .004, respectively. Large stent related perforations were also detected in the short term, suggesting mechanical issues as underlying causes. CONCLUSION: The fabric of EGs may degrade and lead to the development of perforations. The largest perforations are stent related. Their occurrence and size depend on the implantation time and the EG shape affected by arterial tortuosity. The conclusions are limited to the samples from a select explant group.

To patch, or not to patch a common femoral artery, that is the question.

OBJECTIVES: There is no strong evidence to support or reject the use of patch angioplasty (PA) after femoral endarterectomy (FE). The current study aimed to assess early postoperative complications and compare primary patency (PP) rates after FE in patients treated with PA versus direct closure (DC). METHODS: This is a retrospective study of patients admitted during 06/2002-07/2017 with signs and symptoms of chronic lower limb ischemia (Rutherford categories 2-6). Patients with angiographically confirmed stenoses or occlusions of the common femoral arteries (CFAs) and managed with FE with or without PA were included in the study. Early postoperative wound complications were assessed. The PP analysis was based on imaging-confirmed data. The impact of PA on the patency was evaluated in a confounder-adjusted Cox regression model. PP rates were compared with log-rank between the PA and DC groups using Kaplan-Meier survival analysis in the propensity score-matched (PSM) cohorts. RESULTS: A total of 295 primary FEs were identified. The patients' median age was 75 years. A total of 210 patients were managed with PA and 85 with DC. Altogether, 38 (12.9%) local wound complications were registered, 15 (5.1%) of which required re-interventions. There were 9 (3.2%) cases of deep wound infection, 20 (7.0%) seromas, and 11 (3.9%) cases of major bleeding, with no significant difference between the PA and DC groups. All of the infected patches were made of synthetic material, and 83% of them were removed. The PP analysis was performed on 50 PSM patient pairs with a median age of 74 years. The median imaging-confirmed follow-up lengths were 77 months (IQR = 47 months) for the PA patients and 27 months (IQR = 64 months) for the DC patients. The preoperative median diameter of the CFA was 8.8 mm (IQR = 3.4). The 5 year primary patency rates of CFAs with a minimum diameter of 5.5 mm managed with PA or DC exceeded 91%, p > 0.05. Female sex was associated with the loss of PP, odds ratio 4.17, p = 0.046. CONCLUSIONS: Wound complications after FE with or without patching are not uncommon and often lead to reoperations. The PP rates of CFAs with a minimum diameter of 5.5 mm and accomplished with or without patching are comparable. Female sex is associated with the loss of patency.

Prognostic risk factors for recurrent acute lower limb ischemia in patients treated with intra-arterial thrombolysis.

OBJECTIVE: The objective of this study was to assess factors predisposing patients to recurrent acute lower limb ischemia (RALLI). METHODS: Acute lower limb ischemia patients treated with catheter-directed thrombolysis (CDT) at Tampere University Hospital and Turku University Hospital between March 2002 and December 2015 were included. The patients' baseline demographics, comorbidities, and other characteristics were assessed retrospectively. Significant factors revealed by univariable analysis were tested in a multivariable model for associations with RALLI. A patency analysis was performed, and the risks of reocclusion were identified. The limb salvage rates after reocclusion were evaluated. RESULTS: Altogether, 303 consecutive patients with a mean age of 71 years (standard deviation, 11.8 years) were included. Of them, 159 (52.5%) were men. A total of 164 (54.1%) native arterial and 139 (45.9%) bypass graft occlusions were initially treated with CDT. On completion of CDT, 204 additional endovascular or conventional surgical procedures on 203 patients were performed to obtain adequate distal perfusion. During a median follow-up of 40 months (interquartile range, 69 months), 40 (24.4%) cases of RALLI occurred in native arteries and 90 (64.7%) in bypass graft patients (P < .001). In native arteries, the absence of appropriate anticoagulant and antiplatelet medication was independently associated with the development of acute reocclusions (hazard ratio, 6.51) in the Cox multivariable regression analysis. The patency rates were 86.6%, 72.2%, and 68.0% at 1 year, 5 years, and 9 years, respectively. In bypass grafts, worsened tibial runoff (crural index III: hazard ratio, 2.40) was independently associated with RALLI. The respective patency rates were 60.5%, 34.0%, and 29.2% for synthetic conduits and 30.8%, 20.5%, and 13.7% for autologous vein grafts at 1 year, 5 years, and 9 years. Altogether, 38 (29.2%) major amputations were performed on patients with reocclusions. Patients with synthetic conduits demonstrated superior limb salvage rates after reocclusion in comparison to native arteries or vein grafts (P = .025). CONCLUSIONS: Appropriate post-thrombolytic antiplatelet or anticoagulant treatment after native arterial events is of great importance, but additional data are needed to improve treatment algorithms. Adequate outflow in bypass graft patients is crucial. Patients with prosthetic bypass grafts have superior limb salvage rates after reocclusion.

Survival of Patients and Treatment-Related Outcome After Intra-Arterial Thrombolysis for Acute Lower Limb Ischemia.

BACKGROUND: The aim of this study is to evaluate the long-term survival and treatment-related outcome in patients treated with intra-arterial thrombolysis for acute lower limb ischemia. METHODS: The study was based on a prospective vascular database with retrospectively obtained supplementary information from the patients' files. Additionally, data on the patients' date and cause of death were obtained from Statistics Finland. A total of 155 patients with symptoms or signs of category I-IIa acute lower limb ischemia and angiographic evidence of native artery or bypass graft thromboembolic events were treated with intra-arterial catheter-directed thrombolysis (CDT). Patients with severe ischemic stages at admission or those with contraindications for thrombolysis (n = 185) were treated with conventional surgical modalities and excluded from further analysis. RESULTS: The mean age of the patients at admission was 73 years (95% confidence interval 70.1-74.6). For descriptive purposes, age quartiles were used (≤64, 65-74, 75-82.5, ≥83). The mean follow-up time was 126.3 months. The primary patency rates of native arteries/bypass grafts were 59.8%/31.7%, 35.4%/17.1%, and 18.7%/15.2% at 1, 5, and 10 years, respectively (P = 0.01). Correspondingly, the respective secondary patency rates were 65.2%/55.6%, 46.7%/39.8%, and 22.8%/30.5% (P = 0.88). A total of 190 additional procedures on 122 patients were required to preserve the patency after hospital discharge. At 1 year the cumulative survival was 78%, at 5 years 56%, and at 10 years 29%. The most common cause of death was cardiovascular (68.5%), predominantly presented by an acute coronary syndrome, while 9.6% died of cancer, 6.8% of pulmonary diseases, 8.2% of cerebrovascular causes, and 19.2% owing to trauma and other reasons. Atrial fibrillation (hazards ratio [HR] 2.31) and age over 83 years (HR 5.23 per age category) were significantly and independently associated with poorer cumulative post-procedural survival. Bypass graft thrombosis was associated with an increase in major amputations after CDT (HR 14.77). However, the presence of synthetic bypass grafts had a protective influence on limb salvage (HR 0.086). A total of 39 (25.2%) major amputations were performed during the follow-up period. Age over 75 years was the only significant and independent factor to negatively impact on amputation-free survival (HR 2.01), which was 24% at 10 years. CONCLUSIONS: The long-term patency after CDT is unfavorable, and additional procedures are needed to preserve adequate distal perfusion. Approximately 30% of the patients are alive at 10 years after the initial CDT. Increasing age and atrial fibrillation have a negative effect on the patients' survival.

Bacterial signatures in thrombus aspirates of patients with lower limb arterial and venous thrombosis.

OBJECTIVE: Increasing data supports the role of bacterial inflammation in adverse events of cardiovascular and cerebrovascular diseases. In our previous research, DNA of bacterial species found in coronary artery thrombus aspirates and ruptured cerebral aneurysms were mostly of endodontic and periodontal origin, where Streptococcus mitis group DNA was the most common. We hypothesized that the genomes of S mitis group could be identified in thrombus aspirates of patients with lower limb arterial and deep venous thrombosis. METHODS: Thrombus aspirates and control blood samples taken from 42 patients with acute or acute-on-chronic lower limb ischemia (Rutherford I-IIb) owing to arterial or graft thrombosis (n = 31) or lower limb deep venous thrombosis (n = 11) were examined using a quantitative real-time polymerase chain reaction to detect all possible bacterial DNA and DNA of S mitis group in particular. The samples were considered positive, if the amount of bacterial DNA in the thrombus aspirates was 2-fold or greater in comparison with control blood samples. RESULTS: In the positive samples the mean difference for the total bacterial DNA was 12.1-fold (median, 7.1), whereas the differences for S mitis group DNA were a mean of 29.1 and a median of 5.2-fold. Of the arterial thrombus aspirates, 57.9% were positive for bacterial DNA, whereas bacterial genomes were found in 75% of bypass graft thrombosis with 77.8% of the prosthetic grafts being positive. Of the deep vein thrombus aspirates, 45.5% contained bacterial genomes. Most (80%) of bacterial DNA-positive cases contained DNA from the S mitis group. Previous arterial interventions were significantly associated with the occurrence of S mitis group DNA (P = .049, Fisher's exact test). CONCLUSIONS: This is the first study to report the presence of bacterial DNA, predominantly of S mitis group origin, in the thrombus aspirates of surgical patients with lower limb arterial and deep venous thrombosis, suggesting their possible role in the pathogenesis of thrombotic events. Additional studies will, however, be needed to reach a final conclusion.

Independent factors predicting early lower limb intra-arterial thrombolysis failure.

BACKGROUND: Risk factors for early catheter-directed intra-arterial thrombolysis failure in acute lower limb ischemia remain unclear. METHODS: One hundred forty-nine limbs with acute artery or bypass graft thrombosis underwent catheter-directed thrombolysis (maximum of 48 hours). A retrospective data analysis was carried out to assess possible risk factors for early, 30-day treatment failure. RESULTS: Seventy-nine men (53%) and 70 women (47%) with a median age of 70 (range 32-93) years were treated. Treatment outcomes were determined as success (N = 115, 77%) or failure (N = 34, 23%). The failure criteria comprised rapid progression of ischemia (N = 4, 2.7%) and major bleeding complications (N = 2, 1.3%), both requiring thrombolysis termination and surgery. Inability to reopen native arteries/grafts (N = 10, 6.7%), run-off vessels (N = 10, 6.7%), in-hospital death (N = 4, 2.7%), the need for major amputation (N = 13, 8.7%), and reocclusions (N = 5, 3.4%) within the 30-day follow-up period were also considered as failures. Multivariate analysis of the risk factors' impact on the success of thrombolysis revealed such independent parameters as hypercholesterolemia (OR 0.16, 95% CI 0.06-0.42, P < 0.0001), previous bypass grafting of the ipsilateral limb (OR 0.18, 95% CI 0.06-0.53, P = 0.002), and duration of ischemia prior to the initiation of thrombolysis (OR 0.95, 95% CI 0.91-0.99, P = 0.009, per day). CONCLUSION: According to our results, factors independently predicting early failure include hypercholesterolemia, previous bypass grafting, and a delay in treatment initiation. Moreover, catheter-directed intra-arterial thrombolysis can be considered safe and effective in the treatment of acute lower limb ischemia.

What We Know From Reports on Type III Endoleak in the Literature.

Objective: To analyse case reports published on the latest generations of endograft (EG) and understand the mechanisms of type III endoleak (EL) development. Methods: A literature review was undertaken of English language case reports and series that concerned modular junction or component disconnection (type IIIa EL) and fabric perforations (type IIIb EL) after endovascular aneurysm repair. Results: Of the 2 785 studies, 56 full texts were chosen to review 73 cases. Type III EL was diagnosed with computed tomography angiography in 67.1% and digital subtraction angiography in 12.3%; the rest were identified during surgery. Of the 73 EG, 65 (89.0%) were made of polyethylene terephthalate and seven (9.6%) were polytetrafluoroethylene. The type of material was not mentioned in one (1.4%) case report. There were 25 (34.2%) type IIIa and 48 (65.8%) type IIIb EL. The most frequent were trunk-trunk in nine (12.3%) and trunk-limb overlap separations in 14 (19.2%). Type IIIb EL in the trunk area was identified in 27 (37.0%) cases, while 21 (28.8%) defects were found in the limbs. Stent fractures were recognised as an underlying mechanism of type IIIb EL development in one report. A combination of fabric lesions in the trunk and limb area was found in one case. Seven type IIIb EL were related to suture disruption or suture-fabric abrasions. Four cases were related to stent-fabric abrasions, and two developed as a result of fabric fatigue owing to kinking. Information on the mechanisms of degradation was only occasionally and scarcely presented. Given the small number of reports and lack of detailed analysis, no definitive conclusions could be drawn. Conclusion: The available information is scarce and does not allow any definitive conclusions to be drawn on the mechanisms that lead to the development of type III EL. Further explant analyses would be beneficial.

Psoas muscle quantified muscle status and long-term mortality after cardiovascular interventions.

RESULTS: In the meta-analysis, psoas muscle measurements were significantly associated with mortality among men (p < 0.05), with high heterogeneity in the associations across all cohorts. There was very little difference in the association between PMA and PMD and mortality (HR 0.83, 95% CI 0.69-0.99, p = 0.002; HR 0.85, 95% CI 0.77-0.94, p = 0.041 for one SD increase in PMA and PMD in the random effects model). Combining PMA and PMD into one composite variable by multiplying their values together showed the most robust association in terms of the magnitude of the effect size in men (HR, 0.77; 95% CI 0.73-0.87, p < 0.001). Indexing PMA to body size did not result in any significant differences in this association. Among women, psoas muscle measurements were not associated with long-term mortality in this meta-analysis. CONCLUSIONS: Different psoas muscle measurements were significantly and very similarly associated with mortality among men but not among women. No single measurement stands out, although combining PMA and PMD seems to be a slightly stronger estimate in terms of effect size and should be considered in further studies.

Significant sarcopenia affecting survival in patients undergoing heavy invasive operations may be preoperatively assessed using images of psoas muscle (PM) from routine computerized tomography but the optimal method for evaluation is unclear. A meta-analysis of individual participant data of over two thousand patients undergoing cardiovascular interventions shows that different PM measurements of surface area and density were significantly and very similarly associated with mortality among men but not among women. Combining PM area with PM density to one estimate of lean psoas muscle area seems to provide the strongest hazard estimate among men.

Challenging treatment of multiple late complications after endovascular aneurysm repair.

BACKGROUND: To report a case of multiple additional procedures after successful endovascular treatment of abdominal aortic aneurysm. METHODS: An endovascular abdominal aortic aneurysm repair with a bifurcated aortic Vanguard endograft successfully performed in 1999 resulted in multiple complications, including endoleaks and a row separation, treated endovascularly. Subsequently, tuberculosis sepsis and prosthesis infection resulted in long-term antibiotic treatment. Additional graft leaks, aneurysm sack growth, and sack ruptures were also treated endovascularly because the patient consistently denied open repair. Endovascular procedures, however, did not solve the problem, turning to be increasingly challenging. The patient finally approved open graft removal and aortobifemoral reconstruction that were successfully performed 11 years after the initial endograft implantation. RESULTS: The patient has recovered from surgery well and is asymptomatic. No evidence of bacterial colonization was found according to the specimen taken during the laparotomy. CONCLUSION: Vanguard and other first-generation aortic endografts are associated with high incidence of complications and reinterventions. Open surgery is a method of choice in similar cases.

The Cardiovascular-Mortality-Based Estimate for Normal Range of the Ankle-Brachial Index (ABI).

Background: The ankle−brachial index (ABI) is a first-line examination in cardiovascular risk evaluation. Since cut-off values for normal ABI vary, the aim of the present study was to identify the cardiovascular-mortality-based estimate for the normal range of the ABI. After determining the reference range for the ABI, the corresponding toe−brachial index (TBI) and toe pressure for normal ABI were analyzed. Methods: All consecutive non-invasive pressure measurements in the vascular laboratory of a large university hospital 2011−2013 inclusive were collected and combined with patient characteristics and official dates and causes of death. Patients with an ABI range of 0.8−1.4 on both lower limbs were included in this study. Results: From 2751 patients, 868 had bilateral ABI values within the inclusion. Both ABI category ranges 0.80−0.89 and 0.90−0.99 had poorer survival compared to ABI categories 1.00−1.29 (p < 0.05). The 1-, 3-, and 5-year cardiovascular-death-free survival for respective ABI categories 0.80−0.99 vs. 1.00−1.29 were 90% vs. 96%, 84% vs. 92%, and 60% vs. 87%. The 1-, 3-, and 5-year overall survival for ABI categories 0.80−0.99 vs. 1.00−1.29 were 85% vs. 92%, 75% vs. 83%, and 42% vs. 74%. Conclusions: Borderline ABI (0.90−0.99) associates with higher overall and cardiovascular mortality compared to ABI values 1.00−1.29.

Risk of symptomatic venous thromboembolism after abdominal aortic aneurysm repair in long-term follow-up of 1021 consecutive patients.

OBJECTIVE: Venous thromboembolism (VTE), including deep venous thrombosis and pulmonary embolism (PE), is an infrequent but consequential and potentially preventable complication after major surgical procedures. The aim of the study was to describe the long-term occurrence of symptomatic VTE in patients undergoing abdominal aortic aneurysm (AAA) repair and to ascertain patient-specific risk factors as well as to compare the rate with that of a reference population. METHODS: The study included all patients who had undergone endovascular or open AAA repair, both elective and urgent/acute cases, at the Tampere University Hospital (Finland) between February 2001 and December 2016; 59% of patients had undergone endovascular and 41% open repair, and 23% of all cases had required urgent or emergency treatment. Information about later treatment episodes for symptomatic VTE and survival data were obtained from national registries. The reference population was obtained from national registries with a random sample of inhabitants matched for age, sex, and location of residence with a 4:1 ratio and was analyzed similarly. RESULTS: Altogether, 1021 patients and 4065 controls were included (88% male; median age, 74 years in both groups). The high-risk period for VTE lasted for approximately 3 months, and during that time, its occurrence was highest in patients with coronary disease (2.5%), after open repair (2.4%), and in an urgent or emergency setting (2.6%), whereas the rate was low after endovascular aneurysm repair (1.0%). The cumulative incidence of VTE at 3 months, 1 year, 3 years, and 5 years was 1.1%, 1.6%, 2.7%, and 4.5% in patients and 0.1%, 0.3%, 1.0%, and 1.8% in the reference population, respectively (P < .001 each). Most VTE events were PE in the patient group. The 5-year mortality rates were 37.9% in patients and 23.8% in controls (P < .001). CONCLUSIONS: The incidence of symptomatic VTE, particularly PE, after AAA repair is significant, in both short-term and long-term follow-up. Open surgery, acute setting, and concomitant coronary disease appear to increase the risk.

Effects of Percutaneous Transluminal Angioplasty of Superficial Femoral Artery on Photoplethysmographic Pulse Transit Times.

We analyze the changes in upper and lower limb pulse transit times (PTT) caused by peripheral artery disease (PAD) and its treatment with percutaneous transluminal angioplasty (PTA) of the superficial femoral artery. PTTs were extracted from the photoplethysmograms (PPG) recorded from an index finger and 2nd toes. PTTs were defined between the R-peaks of the ECG and different reference points of the PPG: foot and peak points, maxima of 1st and 2nd derivative, and by means of intersecting tangents method. Also the PTTs between the toe and finger pulses were analyzed. Our sample consists of 24 subjects examined before and after the PTA and in 1-month follow-up visit. Also 28 older than 65 years controls having normal ankle-to-brachial pressure index (ABI) and no history in cardiovascular diseases as well as 21 younger subjects were examined. The differences between the groups and pre- and post-treatment phases were analyzed by means of non-parametric statistical tests. The changes in the PTTs of upper limb and non-treated lower limb were negligible. The agreement with the reference values, ABI and toe pressures, was studied by kappa-analysis, resulting in kappa-values of 0.33-0.91. Differences in PTTs were found between pre-treatment state of the treated limb, post-treatment state and the follow-up visit, as well as between the pre-treatment state and controls. If patients' age and systolic blood pressure were taken into consideration, the method of lower limb PTT calculation from the peak point turns out feasible in finding the markers of PAD and monitoring post-treatment vascular remodellation.

Lower Limb Pulse Rise Time as a Marker of Peripheral Arterial Disease.

OBJECTIVE: The aim of the study was to show if pulse rise times (PRTs) extracted from photoplethysmographic (PPG) pulse waves (PWs) have an association with peripheral arterial disease (PAD) or its endovascular treatment, percutanoeus transluminal angioplasty (PTA) of the superficial femoral artery. METHODS: Lower and upper limb PPG PWs were recorded and analyzed from 24 patients who suffered from PAD. The measurements were conducted before and after the treatment, and one month later by using transmission-mode PPG-probes placed in the index finger and second toe. Ankle-to-brachial pressure index and toe pressures were used as references in clinical patient measurements. PRTs, i.e., the time from the foot point to the peak point of the PW, were extracted from the PWs and compared bilaterally. The results from the PAD patients were also compared with 31 same-aged and 34 younger control subjects. RESULTS: Statistically significant differences were found between the pretreatment PRTs of the treated limb of the PAD patients and the same-aged control subjects ( , Mann-Whitney U-test). The changes in the PRT of the treated lower limb were observed immediately after the PTA ( , Student's t-test), and after one month ( ), whereas the PRTs of the non-treated lower limb and upper limb did not indicate changes between different examinations. CONCLUSION: Results show that a PRT greater than 240 ms indicates PAD-lesions in the lower limb. SIGNIFICANCE: This proof-of-concept study suggests that the PRT could be an effective and easy-to-use indicator for PAD and monitoring the effectiveness of its treatment.

The effect of percutaneous transluminal angioplasty of superficial femoral artery on pulse wave features.

We aimed to analyze the effects of percutaneous transluminal angioplasty (PTA) of the superficial femoral artery (SFA) on arterial pulse waves (PWs). Altogether 24 subjects i.e. 48 lower limbs were examined including 26 treated lower limbs having abnormal ankle-to-brachial pressure index (ABI) (ABI<0.9 or ABI>1.3) and 22 non-treated lower limbs. The measurements were conducted in pre-, peri- and post-treatment phases as well as in follow-up visit after 1 month. Both ABI and toe pressures measured by standard equipment were used as reference values. PW-derived parameters include ratios of different peaks of the PW and time differences between them as well as aging index. Both treated and non-treated limbs were compared in pre- and post-treatment as well as follow-up visit conditions. The results were evaluated in terms of statistical tests, Bland-Altman-plots, free-marginal multirater κ-analysis and multiple linear regression analysis. PTA was found to cause small changes to the studied PW-derived parameters of the treated limb which were observed immediately after the treatment, but the changes were more pronounced in the follow-up visit. In addition, we observed that the endovascular instrumentation itself does not cause significant changes to the PW-derived parameters. The results show that PW-analysis could be a useful tool for monitoring the treatment-effect of the PTA. However, because the pre-treatment differences of the treated and non-treated limb were small, further studies with subjects having no arterial diseases are required. The study demonstrates the potential of the PW analysis in monitoring vascular abnormalities.