Safety and efficacy of mechanical aspiration thrombectomy for patients with acute lower extremity ischemia

OBJECTIVE

Acute limb ischemia (ALI) is associated with high rates of amputation and consequent morbidity and mortality. The objective of this study is to report on the safety and efficacy of aspiration thrombectomy using the Indigo Aspiration System in patients with lower extremity (LE) ALI.

METHODS

The STRIDE study was an international, multicenter, prospective, study that enrolled 119 participants presenting with LE-ALI. Patients were treated firstline with mechanical thrombectomy using the Indigo Aspiration System, before stenting or angioplasty, or other therapies as determined by treating physician. The primary end point was target limb salvage at 30 days after the procedure. Secondary end points within 30 days included technical success, defined as core laboratory-adjudicated Thrombolysis in Myocardial Infarction (TIMI) 2/3 flow rate immediately after the procedure, changes in modified Society for Vascular Surgery runoff score, improvement of Rutherford classification compared with before the procedure, patency, rate of device-related serious adverse events, and major periprocedural bleeding. Secondary end points that will be evaluated at 12 months include target limb salvage and mortality.

RESULTS

Of the 119 participants enrolled at 16 sites, the mean age was 66.3 years (46.2% female). At baseline (n = 119), ischemic severity was classified as Rutherford I in 10.9%, Rutherford IIa in 54.6%, and Rutherford IIb in 34.5%. The mean target thrombus length was 125.7 ± 124.7 mm. Before the procedure, 93.0% (of patients 107/115) had no flow (TIMI 0) through the target lesion. The target limb salvage rate at 30 days was 98.2% (109/111). The rate of periprocedural major bleed was 4.2% (5/119) and device-related serious adverse events was 0.8% (1/119). Restoration of flow (TIMI 2/3) was achieved in 96.3% of patients (105/109) immediately after the procedure. The median improvement in the modified Society for Vascular Surgery runoff score (before vs after the procedure) was 6.0 (interquartile range, 0.0-11.0). Rutherford classifications also improved after discharge in 86.5% of patients (83/96), as compared with preprocedural scores. Patency at 30 days was achieved in 89.4% of patients (101/113).

CONCLUSIONS

In the STRIDE (A Study of Patients with Lower Extremity Acute Limb Ischemia to Remove Thrombus with the Indigo Aspiration System) study, aspiration thrombectomy with the Indigo System provided a safe and effective endovascular treatment for patients with LE-ALI, resulting in a high rate (98.2%) of successful limb salvage at 30 days, with few periprocedural complications.

Endovascular aortic repair with sac embolization for the prevention of type II endoleaks (the EVAR-SE study): study protocol for a randomized controlled multicentre study in Germany

BACKGROUND

Beyond a certain threshold diameter, abdominal aortic aneurysms (AAA) are to be treated by open surgical or endovascular aortic aneurysm repair (EVAR). In a quarter of patients who undergo EVAR, inversion of blood flow in the inferior mesenteric artery or lumbar arteries may lead to type II endoleak (T2EL), which is associated with complications (e.g. AAA growth, secondary type I endoleak, rupture). As secondary interventions to treat T2EL often fail and may be highly invasive, prevention of T2EL is desirable. The present study aims to assess the efficacy of sac embolization (SE) with metal coils during EVAR to prevent T2EL in patients at high risk.

METHODS

Over a 24-month recruitment period, a total of 100 patients undergoing EVAR in four vascular centres (i.e. Klinikum rechts der Isar of the Technical University of Munich, University Hospital Augsburg, University Hospital Dresden, St. Joseph's Hospital Wiesbaden) are to be included in the present study. Patients at high risk for T2EL (i.e. ≥ 5 efferent vessels covered by endograft or aneurysmal thrombus volume <40%) are randomized to one group receiving standard EVAR and another group receiving EVAR with SE. Follow-up assessments postoperatively, after 30 days, and 6 months involve contrast-enhanced ultrasound scans (CEUS) and after 12 months an additional computed tomography angiography (CTA) scan. The presence of T2EL detected by CEUS or CTA after 12 months is the primary endpoint. Secondary endpoints comprise quality of life (quantified by the SF-36 questionnaire), reintervention rate, occurrence of type I/III endoleak, aortic rupture, death, alteration of aneurysm volume, or diameter. Standardized evaluation of CTA scans happens through a core lab. The study will be terminated after the final follow-up visit of the ultimate patient.

DISCUSSION

Although preexisting studies repeatedly indicated a beneficial effect of SE on T2EL rates after EVAR, patient relevant outcomes have not been assessed until now. The present study is the first randomized controlled multicentre study to assess the impact of SE on quality of life. Further unique features include employment of easily assessable high-risk criteria, a contemporary follow-up protocol, and approval to use any commercially available coil material. Overcoming limitations of previous studies might help SE to be implemented in daily practice and to enhance patient safety.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05665101. Registered on 23 December 2022.

Patients with Acute Limb Ischemia Might Benefit from Endovascular Therapy-A 17-Year Retrospective Single-Center Series of 985 Patients

Acute lower limb ischemia (ALI) is a common vascular emergency, requiring urgent revascularization by open or endovascular means. The aim of this retrospective study was to evaluate patient demographics, treatment and periprocedural variables affecting the outcome in ALI patients in a consecutive cohort in a tertiary referral center. Primary outcome events (POE) were 30-day (safety) and 180-day (efficacy) combined mortality and major amputation rates, respectively. Secondary outcomes were perioperative medical and surgical leg-related complications and the 5-year combined mortality and major amputation rate. Statistical analysis used descriptive and uni- and multivariable Cox regression analysis. In 985 patients (71 ± 9 years, 56% men) from 2004 to 2020, the 30-day and 180-day combined mortality and major amputation rates were 15% and 27%. Upon multivariable analysis, older age (30 d: aHR 1.17; 180 d: 1.27) and advanced Rutherford ischemia stage significantly worsened the safety and efficacy POE (30 d: TASC IIa aHR 3.29, TASC IIb aHR 3.93, TASC III aHR 7.79; 180 d: TASC IIa aHR 1.97, TASC IIb aHR 2.43, TASC III aHR 4.2), while endovascular treatment was associated with significant improved POE after 30 days (aHR 0.35) and 180 days (aHR 0.39), respectively. Looking at five consecutive patient quintiles, a significant increase in endovascular procedures especially in the last quintile could be observed (17.5% to 39.5%, p < 0.001). Simultaneously, the re-occlusion rate as well as the number of patients with any previous revascularization increased. In conclusion, despite a slightly increasing early re-occlusion rate, endovascular treatment might, if possible, be favorable in ALI treatment.

Eigenschaften und Einsatz von verschiedenen Drähten in der Gefäßmedizin

Erst das Zusammenspiel von Drähten und Kathetern hat die moderne endovaskuläre Therapie möglich gemacht. Nur der richtige Draht mit seinen speziellen Eigenschaften, abhängig vom Gefäßgebiet, kann zum Erfolg führen. Deswegen ist es wichtig, die Eigenschaften der eingesetzten Drähte zu kennen und zu verstehen. Drähte werden prinzipiell in 3 Gruppen (Zugangs‑, Sondierungs- und Haltedrähte) eingeteilt. Elementare Eigenschaften eines Drahtes sind Drahtlänge, Durchmesser, Steifigkeit, Beschichtung, Spitzenkonfiguration, Torsionsstabilität und Tip Load. Es gibt keinen Draht, der für alle Bereiche eingesetzt werden kann. Aortale Therapien im thorakalen Beriech brauchen ultrasteife 0,035″ Drähte, welche mindestens 260 cm lang sind. Tip Load, Spitzenkonfiguration und Torsionsstabilität sind von untergeordneter Bedeutung, während bei Rekanalisationsdrähten für den Unterschenkel gerade diese wichtig für den Erfolg sind.

Diagnostic performance of quantitative and qualitative parameters for the diagnosis of aortic graft infection using [18F]-FDG PET/CT

PURPOSE

The aim of this study was the evaluation of quantitative and qualitative parameters for the diagnosis of aortic graft infection (AGI) using [18F]-FDG PET/CT.

METHODS

PET/CT was performed in 50 patients with clinically suspected AGI. 12 oncological patients with aortic repair but without suspicion of AGI were included in the analysis to serve as control cohort. The [18F]-FDG uptake pattern around the graft was assessed using (a) a five-point visual grading scale (VGS), (b) SUVmax and (c) different graft-to-background ratios (GBRs). The diagnostic performance of VGS, SUVmax and GBRs was assessed and compared by ROC analysis.

RESULTS

28 infected and 34 uninfected grafts were identified by standard of reference. SUVmax and VGS were the most powerful predictors for the diagnosis of AGI according to the area under the curve (AUC 0.988 and 0.983, respectively) without a significant difference compared to GBRs. SUVmax and VGS showed congruent and accurate findings in 54 patients (i.e. either both positive or negative), yielding sensitivity and specificity (100%) in this subgroup of patients.

CONCLUSION

Quantitative analysis by SUVmax and qualitative analysis by VGS are highly effective in the diagnosis of AGI and should be tested as an outcome measure in prospective trials.

18F-FDG PET/MRI compared with clinical and serological markers for monitoring disease activity in patients with aortitis and chronic periaortitis

OBJECTIVES

We compared the diagnostic value of fully integrated 18F-FDG PET/MRI to that of clinical and serological markers for monitoring disease activity in patients with aortitis/chronic periaortitis (A/CPA) during immunosuppressive therapy.

METHODS

Patients positive for A/CPA at the initial and at least 2 consecutive PET/MRI studies were included for retrospective analysis. Imaging (qualitative and quantitative analysis), clinical, and serologic (C-reactive protein, erythrocyte sedimentation rate) assessments were determined at each visit, and their findings compared. Differences in various PET/MRI parameters, clinical symptoms, and serologic markers during therapy between first and second visits were tested for statistical significance. Spearman's rank correlation coefficient was calculated to relate imaging to serologic marker changes between the first 2 visits.

RESULTS

Serial assessments were performed in 12 patients with A/CPA, over 34 visits. PET/MRI suggested active disease in 22/34 (64.7%) studies, whereas clinical assessment and serological analysis were positive in only 18/34 (52.9%) and 17/34 (50%) cases, respectively. Disease activity assessment differed between PET/MRI, and clinical and serological markers, in 8/34 (23.5%) and 9/34 (26.5%) cases, respectively. Imaging and serologic parameters (p < 0.009) and clinical symptoms (p = 0.063) predominantly improved at the second visit. Changes from the first to the second visit were not correlated between PET/MRI and serologic markers.

CONCLUSIONS

Fully integrated 18F-FDG PET/MRI provides a comprehensive imaging approach with data on vascular/perivascular inflammation that is complementary to clinical and laboratory assessments. This highlights the potential value of imaging-based disease activity monitoring, which might have a crucial impact on clinical management in patients with A/CPA.

Three-dimensional fat-saturated T1-weighted Cartesian volumetric interpolated breath-hold examination (VIBE) for the diagnosis of aortitis in patients with suspected large vessel vasculitis: a comparative study with 18F-FDG PET applying fully integrated PET/MRI

AIM

To evaluate the feasibility of T1-weighted (T1W) three-dimensional (3D) fat saturated Cartesian volumetric interpolated breath-hold examination (VIBE) magnetic resonance imaging (MRI) sequence for the diagnosis of aortitis in patients with suspected large vessel vasculitis (LVV) applying fully integrated 2-[¹⁸F]-fluoro-2-deoxy-d-glucose (¹⁸F-FDG) positron-emission tomography (PET)/MRI.

MATERIAL AND METHODS

Fourteen patients with aortitis and 14 patients with a negative study for aortitis using ¹⁸F-FDG PET as the standard of reference for the evaluation of inflammatory aortic involvement were included retrospectively. All patients were imaged at 3 T using T1W VIBE pre- and post-contrast. Four aortic segments were evaluated for image quality (IQ), diagnostic confidence (DC), and the degree of inflammatory activity (IA) using a Likert scale. Binomial and generalised estimating equation model tests were used to assess the diagnostic performance of T1W VIBE. Cohen's k was applied to test for interobserver reproducibility with respect to IA. Spearman's rank correlation coefficient was calculated to examine correlations between IQ, DC, IA, and PET results.

RESULTS

On a patient- and segment-based analysis, sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 85.7% and 59.8%, 100% and 100%, 100% and 100%, 87.5% and 68%, and 92.9% and 82.1%, respectively. IQ and DC were acceptable to good in all examinations and substantial interobserver agreement was observed for IA (Cohen's k = 0.69). IQ and DC as well as IA and ¹⁸F-FDG vessel wall uptake were significantly correlated (r=0.763 and 0.679, respectively; p<0.0001).

CONCLUSION

T1W 3D fat saturated VIBE MRI allows diagnosis of aortitis and may aid in the management of patients with suspected LVV.

Biobanking: Objectives, Requirements, and Future Challenges-Experiences from the Munich Vascular Biobank

Collecting biological tissue samples in a biobank grants a unique opportunity to validate diagnostic and therapeutic strategies for translational and clinical research. In the present work, we provide our long-standing experience in establishing and maintaining a biobank of vascular tissue samples, including the evaluation of tissue quality, especially in formalin-fixed paraffin-embedded specimens (FFPE). Our Munich Vascular Biobank includes, thus far, vascular biomaterial from patients with high-grade carotid artery stenosis (n = 1567), peripheral arterial disease (n = 703), and abdominal aortic aneurysm (n = 481) from our Department of Vascular and Endovascular Surgery (January 2004–December 2018). Vascular tissue samples are continuously processed and characterized to assess tissue morphology, histological quality, cellular composition, inflammation, calcification, neovascularization, and the content of elastin and collagen fibers. Atherosclerotic plaques are further classified in accordance with the American Heart Association (AHA), and plaque stability is determined. In order to assess the quality of RNA from FFPE tissue samples over time (2009–2018), RNA integrity number (RIN) and the extent of RNA fragmentation were evaluated. Expression analysis was performed with two housekeeping genes—glyceraldehyde 3-phosphate dehydrogenase (GAPDH) and beta-actin (ACTB)—using TaqMan-based quantitative reverse-transcription polymerase chain reaction (qRT)-PCR. FFPE biospecimens demonstrated unaltered RNA stability over time for up to 10 years. Furthermore, we provide a protocol for processing tissue samples in our Munich Vascular Biobank. In this work, we demonstrate that biobanking is an important tool not only for scientific research but also for clinical usage and personalized medicine.

Association of time under immunosuppression and different immunosuppressive medication on periodontal parameters and selected bacteria of patients after solid organ transplantation

Background

Aim of this study was to investigate the association of the time under immunosuppression and different immunosuppressive medication on periodontal parameters and selected periodontal pathogenic bacteria of immunosuppressed patients after solid organ transplantation (SOT).

Material and Methods

169 Patients after SOT (lung, liver or kidney) were included and divided into subgroups according their time under (0-1, 1-3, 3-6, 6-10 and >10 years) and form of immunosuppression (Tacrolimus, Cyclosporine, Mycophenolate, Glucocorticoids, Sirolimus and monotherapy vs. combination). Periodontal probing depth (PPD) and clinical attachment loss (CAL) were assessed. Periodontal disease severity was classified as healthy/mild, moderate or severe periodontitis. Subgingival biofilm samples were investigated for eleven selected potentially periodontal pathogenic bacteria using polymerasechainreaction.

Results

The mean PPD and CAL as well as prevalence of Treponema denticola and Capnocytophaga species was shown to be different but heterogeneous depending on time under immunosuppression (p<0.05). Furthermore, only the medication with Cyclosporine was found to show worse periodontal condition compared to patients without Cyclosporine (p<0.05). Prevalence of Porphyromonas gingivalis, Tannerella forsythia and Fusobacterium nucleatum was reduced and prevalence of Parvimonas micra and Capnocytophaga species was increased in patients under immunosuppression with Glucocorticoids, Mycophenolate as well as combination therapy.

Conclusions

Time under and form of immunosuppression might have an impact on the clinical periodontal and microbiological parameters of patients after SOT. Patients under Cyclosporine medication should receive increased attention. Differences in subgingival biofilm, but not in clinical parameters were found for Glucocorticoids, Mycophenolate and combination therapy, making the clinical relevance of this finding unclear.

Key words:Immunosuppression, organ transplantation, periodontitis, periodontal bacteria.

Abstract 304: Association Between Plaque Morphology and Time Interval After the Neurologic Index Event in Patients With Symptomatic Carotid Stenosis

Objectives: Instable plaques are more common in patients with symptomatic carotid stenosis compared to asymptomatic patients. Clinically symptomatic patients are at high risk for a recurrent stroke in the first days after a neurologic index event. Histopathologic plaque stabilisation or remodelling mechanisms of symptomatic plaques are unclear. Therefore, our study aimed to find changes of plaque morphology in dependence of time interval between neurologic index event and plaque removal.

Methods: Plaques of patients that were removed from surgically treated patients with symptomatic carotid stenosis between 2004 and 2016 were included. Histological analyses of those carotid plaques were performed to assess the type of plaque (American Heart Association classification), the stability of plaque (thickness of the fibrous cap </>200μm), the extent of calcification, inflammation, neovascularization and the deposition of collagen and elastin. Statistical analysis was applied in form of an ordinal regression analysis, adjusted for common risk factors of atherosclerosis.

Results: Out of 348 included plaques, the patients’ median age was 71 (Q1-Q3, 65 - 77) years and 69% were male. Median time interval between index event and plaque removal was 10 days (Q1-Q3, 4-28 days). Most common index event was a transient ischemic attack with 37% (128 of 348), followed by stroke in 28% (97 of 348), amaurosis fugax in 22% (76 of 348) and instable symptoms (crescendo transient ischemic attack, stroke in evolution) in 12% (43 of 348), respectively. The ordinal regression analysis revealed, that the time interval as continuous independent variable had no significant influence on plaque type, plaque stability, extent of calcification, inflammation or neovascularization and the deposition of collagen and elastin.

Conclusions: The examined plaque morphology features of patients with symptomatic carotid stenosis showed no differences in relation to the time interval between neurologic index event and plaque removal. To find potential symptomatic plaque remodelling mechanisms, currently ongoing molecular and histomorphological analysis aim at identifying novel markers of apoptosis and cell fate-driven mechanisms in fibrous cap-enriched vascular smooth cells.

The "Intermediate" CD14++CD16+ monocyte subset increases in severe peripheral artery disease in humans

Monocytes are key players in atherosclerotic. Human monocytes display a considerable heterogeneity and at least three subsets can be distinguished. While the role of monocyte subset heterogeneity has already been well investigated in coronary artery disease (CAD), the knowledge about monocytes and their heterogeneity in peripheral artery occlusive disease (PAOD) still is limited. Therefore, we aimed to investigate monocyte subset heterogeneity in patients with PAOD. Peripheral blood was obtained from 143 patients suffering from PAOD (Rutherford stage I to VI) and three monocyte subsets were identified by flow cytometry: CD14⁺⁺CD16⁻ classical monocytes, CD14⁺CD16⁺⁺ non-classical monocytes and CD14⁺⁺CD16⁺ intermediate monocytes. Additionally the expression of distinct surface markers (CD106, CD162 and myeloperoxidase MPO) was analyzed. Proportions of CD14⁺⁺CD16⁺ intermediate monocyte levels were significantly increased in advanced stages of PAOD, while classical and non-classical monocytes displayed no such trend. Moreover, CD162 and MPO expression increased significantly in intermediate monocyte subsets in advanced disease stages. Likewise, increased CD162 and MPO expression was noted in CD14⁺⁺CD16⁻ classical monocytes. These data suggest substantial dynamics in monocyte subset distributions and phenotypes in different stages of PAOD, which can either serve as biomarkers or as potential therapeutic targets to decrease the inflammatory burden in advanced stages of atherosclerosis.

Age-associated changes in human carotid atherosclerotic plaques

Little is known about changes in carotid plaque morphology during aging and the possible impact on cardiovascular events. Only few studies addressed so far age-related modifications within atherosclerotic lesions. Therefore, in this work we endeavored to summarize the current knowledge about changing of plaque composition in elderly. The data from hitherto existing studies confirm that atherosclerotic plaques undergo distinct alternations with advanced age. However, the results are often ambiguous and the changes do not seem to be as disastrous as expected. Interestingly, none of the studies could definitely evidence increased plaque vulnerability with advanced age. Nevertheless, based on the previous work showing decrease in elastin fibers, fibroatheroma, SMCs, overall cellularity and increase in the area of lipid core, hemorrhage, and calcification, the plaque morphology appears to transform toward unstable plaques. Otherwise, even if inflammatory cells often accumulate in plaques of younger patients, their amount is reduced in the older age and so far no clear association has been observed between thin fibrous cap and aging. Thus, the accurate contribution of age-related changes in plaque morphology to cardiovascular events has yet to be elucidated. KEY MESSAGES Composition of carotid atherosclerotic lesions changes during aging. These alternations are however, just moderate and depend upon additional variables, such as life style, accompanying disease, genetics, and other factors that have yet to be determined. Based on the current data, the age-associated plaque morphology seems to transform toward vulnerable plaques. However, the changes do not seem to be as disastrous as expected.

Increased intermediate CD14++CD16++ monocyte subset levels associate with restenosis after peripheral percutaneous transluminal angioplasty

BACKGROUND AND AIMS

We aimed at studying the association of three major human monocyte subsets after percutaneous transluminal angioplasty (PTA) in patients with femoropopliteal disease.

METHODS

We prospectively studied 67 sequential patients (40 male, 27 female; mean age 71 ± 11 years) treated with femoropopliteal angioplasty. Multi-color flow cytometry characterized monocyte subsets from venous blood for expression of CD14 and CD16 and intracellular myeloperoxidase (MPO) prior to, and 3, 6 and 12 months post PTA. Analyses tested associations between monocyte subsets and risk for restenosis.

RESULTS

16/67 patients (24%) developed restenosis within 12 months after PTA. Patients with hyperlipidemia had increased risk for restenosis (HR = 1.7, 95% CI 0.7-2.9, p = 0.001). Increased baseline monocytes associated with an increased risk of late restenosis (HR = 4.9, 95% CI: 1.3-18.6, p = 0.047). CD14⁺⁺CD16⁺⁺ 'intermediate' monocytes assessed at baseline, and after 3, 6, and 12 months significantly associated with the risk for subsequent restenosis: HR = 3.9 (95% CI: 2.4-6.5, p = 0.029), HR = 5.7 (95% CI = 0.7-44.7, p = 0.013), HR = 6.5 (95% CI: 2.5-16.9, p = 0.001) and HR = 1.5 (95% CI = 1.4-15.5 p = 0.001), respectively. Moreover, the probability for freedom of restenosis decreased with increased levels of intermediate subsets at 12 months after PTA. Additionally, intracellular MPO expression in CD14⁺⁺CD16⁺⁺ measured at 3, 6 and 12 months associated with an increased restenosis risk (HR = 1.5, 95% CI: 0.8-2.1, p = 0.214, HR = 1.9, 95% CI: 1.0-2.3 p = 0.051 and HR = 1.4, 95% CI: 1.0-1.8, p = 0.052).

CONCLUSIONS

Our results imply altered innate immunity after angioplasty. Elevated CD14⁺⁺CD16⁺⁺ intermediate monocyte frequencies and increased MPO expression may identify individuals at heightened risk for restenosis.

Impact of sex and age on carotid plaque instability in asymptomatic patients-results from the Munich Vascular Biobank

BACKGROUND

It is still a controversial issue whether carotid endarterectomy (CEA) for asymptomatic carotid stenosis is superior to best medical treatment. The aim of this study was therefore to analyze the impact of sex and age on carotid plaque instability in asymptomatic patients undergoing CEA.

PATIENTS AND METHODS

Atherosclerotic plaques from 465 asymptomatic patients with high-grade carotid artery stenosis (2004 - 2013) at the Munich Vascular Biobank were analyzed. Ascertainment of lesion stability/instability was performed on formalin-fixed paraffin-embedded tissue samples using hematoxylin-eosin and elastic van Gieson staining. Unstable plaques were considered lesions with a fibrous cap < 200 µm overlaying lipid-rich atheroma.

RESULTS

The average age of the patients was 69.3 ± 8.2 years. Independent of age, asymptomatic men had in total more frequently unstable plaques in contrast to women (41 % versus 52%, p = 0.042). No differences were found in plaque instability between age-related quartiles (< 65, 65- 69, 70 - 74, > 74 years) for female sex (p = 0.422). In men, a continuous increase in plaque instability with age was observed, without achieving statistical significance (p = 0.125). The greatest differences between male and female sex were found in the last quartile (> 74 years), without achieving statistical significance (p = 0.053). The chance of unstable carotid plaques in men was significantly higher than in women (OR = 1.562, p = 0.040). The probability of age-associated quartiles related to the first quartile demonstrated significant increase in plaque instability in the group of 65- to 69-year-old patients (OR 1.867, p = 0.024) and for patients older than 74 years (OR 1.740, p = 0.040).

CONCLUSIONS

Asymptomatic men had in total more frequently unstable plaques in contrast to women. Thus, male sex seems to be an additional risk factor for ischemic stroke.

Emergency cesarean section due to acute aortic dissection type A (Debakey I) without Marfan syndrome: a case report and review of the literature

BACKGROUND

Acute aortic dissection during pregnancy is an uncommon but important emergency due to its lethal risk to both mother and child. The dissection usually involves the ascending aorta or the aortic arch. Although additional affection of the descending aorta up to bifurcation is possible, further increasing the risk of organ malperfusion, full-length aortic dissection (DeBakey I) is known to be very rare. Dissection during pregnancy has been reported predominantly in combination with Marfan syndrome. Acute aortic dissection Stanford type A (AADA) DeBakey I during pregnancy without signs of Marfan syndrome as a warning signal is very uncommon in the current literature.

OBJECTIVES

The etiology, diagnosis, differential diagnosis, and management of this rare disease are discussed in relation to the current literature.

CASE REPORT

We report the case of an athletic 34-year-old woman in the third trimester of pregnancy, without history of previous diseases, who presented to our Emergency Department after collapsing. In the resuscitation department, an emergency cesarean section was performed due to the start of circulation failure in the mother. Computed tomography scan revealed a severe aortic dissection starting from 1 cm distal the aortic valve over the full length up to the iliac arteries, involving the brachiocephalic and carotid arteries up to the level of the larynx. Emergency replacement of the ascending aorta and the aortic arch was performed. Both the mother and baby survived and were doing well 1 year postoperatively.

CONCLUSION

This alarming result of AADA (DeBakey I) in late pregnancy without obvious warnings such as Marfan syndrome illustrates the importance of performing early imaging in similar cases.

The determination of tissue perfusion and collateralization in peripheral arterial disease with indocyanine green fluorescence angiography

PURPOSE

Indocyanine green (ICG) fluorescence angiography is used to evaluate tissue perfusion in many different medical fields. This study aims to evaluate the value of ICG angiography in the determination of tissue perfusion in the PAD lower extremities.

MATERIAL AND METHODS

In a prospective clinical study, ICG angiography was used to evaluate tissue perfusion and collateralization in 30 PAD patients. The perfusion index and maximum fluorescence intensity (MPI) were calculated as arterial perfusion parameters.

RESULTS

Significant differences in the perfusion index were found for the different PAD stages (p < 0.001). Poor collateralization was associated with a significantly lower perfusion index than good collateralization (p = 0.003). A ROC analysis for the perfusion index showed a positive likelihood ratio of 6.00 and a negative likelihood ratio of 0.00 with an area under the curve of 0.949 to discriminate critical and non-critical PAD.

CONCLUSION

ICG angiography is a promising diagnostic tool to quantify tissue perfusion and demonstrate critical limb ischemia and collateralization in lower extremities affected by PAD.

Early postoperative detection of tissue necrosis in amputation stumps with indocyanine green fluorescence angiography

OBJECTIVE

Amputations of the lower extremity due to irreversible ischemic tissue loss are performed as distally as possible. Therefore, oftentimes wound-healing disorders develop, requiring additional surgical treatment.

METHODS

The amputations stumps of 10 patients with irreversible ischemic tissue loss due to arteriosclerosis were investigated within 72 hours postoperatively with indocyanine green (ICG) fluorescence.

RESULTS

For 6 of the investigated stumps, no perfusion deficit could be seen through fluorescence angiography. All stumps displayed primary healing. In the fluorescence angiography of 3 amputations, stump perfusions deficits predicted later tissue necrosis and had to be amputated again in a second operation. One amputation wound showed a small ICG perfusion deficit that represented a blood clot.

CONCLUSION

Indocyanine green fluorescence angiography allows a perfusion analysis of amputation stumps and therefore a prediction of the expected tissue necrosis. This tool may allow reliable prediction of amputation level.

Differential response of cultured parsley cells to elicitors from two non-pathogenic strains of fungi. Microsomal conversion of (+)marmesin into psoralen

Microsomal fractions isolated from parsley cell suspension cultures, which had been challenged with an elicitor from either Alternaria carthami or Phytophthora megasperma f. sp. glycinea, catalyzed the formation of psoralen from synthetic [3-14C](+)marmesin. Whereas psoralen was the only product formed in incubations with Alternaria-induced microsomes, another unidentified product was isolated from incubations with Phytophthora-induced microsomes. The latter product is neither a precursor nor a product of psoralen. In contrast, microsomes isolated from non-induced parsley cells lacked both of these catalytic activities. The formation of psoralen depends on NADPH as a cofactor and molecular oxygen. Blue-light-reversible CO inhibition and inhibition by various synthetic chemicals known to bind to cytochromes P450 indicated that the reaction is catalyzed by an elicitor-inducible cytochrome P450-dependent psoralen synthase. Fractionation of microsomal preparations by centrifugation revealed that psoralen synthase is associated with the endoplasmic reticulum. Our results suggest that the endoplasmic reticulum of cultured parsley cells is the primary target in the previously reported differential induction by elicitors from these two non-pathogenic strains of fungi.

Insulin release in response to calcium in the diagnosis of insulinoma

A calcium infusion (4 mg Ca++/kg/hr) significantly increased plasma insulin levels and reduced blood glucose in 4 patients with insulin-secreting pancreatic islet cell tumors. These parameters were not altered by a similar infusion of calcium in normal volunteers, 2 patients with alimentary hypoglycemia, and 2 with functional hypoglycemia. No difference in response was observed between patients with benign and malignant beta-cell tumors. Infusion of diazoxide (600 mg) with calcium blocked the stimulation of the latter on insulin secretion. The results indicate the usefulness of calcium infusion in the diagnosis of insulin-secreting tumor.