Final Study Report of Andexanet Alfa for Major Bleeding With Factor Xa Inhibitors

BACKGROUND

Andexanet alfa is a modified recombinant inactive factor Xa (FXa) designed to reverse FXa inhibitors. ANNEXA-4 (Andexanet Alfa, a Novel Antidote to the Anticoagulation Effects of Factor Xa Inhibitors) was a multicenter, prospective, phase-3b/4, single-group cohort study that evaluated andexanet alfa in patients with acute major bleeding. The results of the final analyses are presented.

METHODS

Patients with acute major bleeding within 18 hours of FXa inhibitor administration were enrolled. Co-primary end points were anti-FXa activity change from baseline during andexanet alfa treatment and excellent or good hemostatic efficacy, defined by a scale used in previous reversal studies, at 12 hours. The efficacy population included patients with baseline anti-FXa activity levels above predefined thresholds (≥75 ng/mL for apixaban and rivaroxaban, ≥40 ng/mL for edoxaban, and ≥0.25 IU/mL for enoxaparin; reported in the same units used for calibrators) who were adjudicated as meeting major bleeding criteria (modified International Society of Thrombosis and Haemostasis definition). The safety population included all patients. Major bleeding criteria, hemostatic efficacy, thrombotic events (stratified by occurring before or after restart of either prophylactic [ie, a lower dose, for prevention rather than treatment] or full-dose oral anticoagulation), and deaths were assessed by an independent adjudication committee. Median endogenous thrombin potential at baseline and across the follow-up period was a secondary outcome.

RESULTS

There were 479 patients enrolled (mean age, 78 years; 54% male, 86% White; 81% anticoagulated for atrial fibrillation at a median time of 11.4 hours since last dose, with 245 (51%) on apixaban, 176 (37%) on rivaroxaban, 36 (8%) on edoxaban, and 22 (5%) on enoxaparin. Bleeding was predominantly intracranial (n=331 [69%]) or gastrointestinal (n=109 [23%]). In evaluable apixaban patients (n=172), median anti-FXa activity decreased from 146.9 ng/mL to 10.0 ng/mL (reduction, 93% [95% CI, 94-93]); in rivaroxaban patients (n=132), it decreased from 214.6 ng/mL to 10.8 ng/mL (94% [95% CI, 95-93]); in edoxaban patients (n=28), it decreased from 121.1 ng/mL to 24.4 ng/mL (71% [95% CI, 82-65); and in enoxaparin patients (n=17), it decreased from 0.48 IU/mL to 0.11 IU/mL (75% [95% CI, 79-67]). Excellent or good hemostasis occurred in 274 of 342 evaluable patients (80% [95% CI, 75-84]). In the safety population, thrombotic events occurred in 50 patients (10%); in 16 patients, this occurred during treatment with prophylactic anticoagulation that began after the bleeding event. No thrombotic episodes occurred after oral anticoagulation restart. Specific to certain populations, reduction of anti-FXa activity from baseline to nadir significantly predicted hemostatic efficacy in patients with intracranial hemorrhage (area under the receiver operating characteristic curve, 0.62 [95% CI, 0.54-0.70]) and correlated with lower mortality in patients <75 years of age (adjusted P=0.022; unadjusted P=0.003). Median endogenous thrombin potential was within the normal range by the end of andexanet alfa bolus through 24 hours for all FXa inhibitors.

CONCLUSIONS

In patients with major bleeding associated with the use of FXa inhibitors, treatment with andexanet alfa reduced anti-FXa activity and was associated with good or excellent hemostatic efficacy in 80% of patients.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT02329327.

[Less is more in cardiology and angiology]

Cardiovascular medicine is one of the most resource-consuming parts of the healthcare system and many examples of overdiagnostic and overtreatment can be found. The present article presents just three of these, one from cardiology and two from vascular medicine. The topic of chronic coronary heart disease concerns the unequivocal proof of ischemia before a coronary intervention. The sections on Duplex sonography of the cervical blood vessels and the diagnostics of thrombophilia describe which valid clinical problems may justify the performance of these examinations at all. The potential for harm caused by overdiagnostics in both cases lies not only in the unnecessary use of resources but, more importantly, in the subsequent overtreatment. The few appropriate indications are described in detail.

Comparative clinical prognosis of massive and non-massive pulmonary embolism: A registry-based cohort study

AIMS

Little is known about the prognosis of patients with massive pulmonary embolism (PE) and its risk of recurrent venous thromboembolism (VTE) compared with non-massive PE, which may inform clinical decisions. Our aim was to compare the risk of recurrent VTE, bleeding, and mortality after massive and non-massive PE during anticoagulation and after its discontinuation.

METHODS AND RESULTS

We included all participants in the RIETE registry who suffered a symptomatic, objectively confirmed segmental or more central PE. Massive PE was defined by a systolic hypotension at clinical presentation (<90 mm Hg). We compared the risks of recurrent VTE, major bleeding, and mortality using time-to-event multivariable competing risk modeling. There were 3.5% of massive PE among 38 996 patients with PE. During the anticoagulation period, massive PE was associated with a greater risk of major bleeding (subhazard ratio [sHR] 1.72, 95% confidence interval [CI] 1.28-2.32), but not of recurrent VTE (sHR 1.15, 95% CI 0.75-1.74) than non-massive PE. An increased risk of mortality was only observed in the first month after PE. After discontinuation of anticoagulation, among 11 579 patients, massive PE and non-massive PE had similar risks of mortality, bleeding, and recurrent VTE (sHR 0.85, 95% CI 0.51-1.40), but with different case fatality of recurrent PE (11.1% versus 2.4%, P = .03) and possibly different risk of recurrent fatal PE (sHR 3.65, 95% CI 0.82-16.24).

CONCLUSION

In this large prospective registry, the baseline hemodynamic status of the incident PE did not influence the risk of recurrent VTE, during and after the anticoagulation periods, but was possibly associated with recurrent PE of greater severity.

Anticoagulation treatment of cancer patients with deep or superficial leg vein thrombosis - a retrospective observational study of German statutory health insurance claims data (the CERTIFICAT initiative)

Background: Thrombosis is a common complication of cancer with a negative impact on quality of life and overall prognosis. Guidelines recommend low-molecular-weight heparin (LMWH) as initial and prolonged anticoagulation treatment. Little is known about current treatment patterns of these patients in ambulatory care. Patients and methods: The current retrospective observational study interrogates a large German statutory health insurance claims database in order to understand which kind of data can be extracted and analysed. An age- and sex-adjusted sample of about 4.1 million insured people from 2011 to 2016 could be used. Cancer patients with incident deep and superficial leg vein thrombosis were identified. Patients with preexisting cancer were allocated to a normal risk group; those who suffered from simultaneously diagnosed cancer and thrombosis were classified as high-risk group. Results: We identified 322,600 patients with inpatient or outpatient documented cancer diagnosis in at least two different quarters within one year. 87,755 patients were identified with an incident deep or superficial vein thrombosis. 8,201 patients suffered from both cancer and incident thrombosis. 56.9% of the patients received an anticoagulation regimen with predominant LMWH prescription, 24.2% vitamin K antagonists, 17.2% direct oral anticoagulants; in 1.7% of patients, no predominant anticoagulant drug/regime could be identified. On average, patients were prescribed anticoagulants for 4.5 months. An estimate of clinically relevant gastrointestinal bleeding could be derived (1.8% of patients). Conclusions: The dataset allows assigning detailed information of anticoagulant prescriptions in ambulatory care to well-defined groups of cancer patients. A first analysis suggests that in Germany current medical care of patients with cancer-related deep or superficial vein thrombosis does not entirely comply with guideline recommendations regarding type and duration of anticoagulation.

D-dimer levels and risk of recurrence following provoked venous thromboembolism: findings from the RIETE registry

BACKGROUND

Patients with venous thromboembolism (VTE) secondary to transient risk factors may develop VTE recurrences after discontinuing anticoagulation. Identifying at-risk patients could help to guide the duration of therapy.

METHODS

We used the RIETE database to assess the prognostic value of d-dimer testing after discontinuing anticoagulation to identify patients at increased risk for recurrences. Transient risk factors were classified as major (postoperative) or minor (pregnancy, oestrogen use, immobilization or recent travel).

RESULTS

In December 2018, 1655 VTE patients with transient risk factors (major 460, minor 1195) underwent d-dimer measurements after discontinuing anticoagulation. Amongst patients with major risk factors, the recurrence rate was 5.74 (95% CI: 3.19-9.57) events per 100 patient-years in those with raised d-dimer levels and 2.68 (95% CI: 1.45-4.56) in those with normal levels. Amongst patients with minor risk factors, the rates were 7.79 (95% CI: 5.71-10.4) and 3.34 (95% CI: 2.39-4.53), respectively. Patients with major risk factors and raised d-dimer levels (n = 171) had a nonsignificantly higher rate of recurrences (hazard ratio [HR]: 2.14; 95% CI: 0.96-4.79) than those with normal levels. Patients with minor risk factors and raised d-dimer levels (n = 382) had a higher rate of recurrences (HR: 2.34; 95% CI: 1.51-3.63) than those with normal levels. On multivariate analysis, raised d-dimers (HR: 1.74; 95% CI: 1.09-2.77) were associated with an increased risk for recurrences in patients with minor risk factors, not in those with major risk factors.

CONCLUSIONS

Patients with raised d-dimer levels after discontinuing anticoagulant therapy for VTE provoked by a minor transient risk factor were at an increased risk for recurrences.

P3849Baseline profile of patients treated for acute venous thromboembolism in routine clinical practice according to age and renal function in the RE-COVERY DVT/PE global cohort study

Background

Observational studies provide the opportunity to evaluate routine practice without the selection and treatment criteria imposed in randomized clinical trials (RCTs).

Purpose

Using data from the RE-COVERY DVT/PE global observational study (enrolment January 2016 to May 2017), we describe the baseline profile of patients treated for acute venous thromboembolism (VTE) in routine clinical practice according to age and renal function.

Methods

Baseline patient characteristics, clinical features (comorbidities/medical history), and anticoagulant therapy were tabulated descriptively for the subgroups of age (<75, ≥75 years) and creatinine clearance (<30, 30 to <50 [moderate impairment], 50 to <80 [mild impairment], ≥80 mL/min). Anticoagulant therapy at baseline and at hospital discharge or 14 days after diagnosis (whichever was later) was recorded.

Results

In this observational study of 6122 patients with acute deep vein thrombosis, the proportions of patients at baseline who were ≥75 years of age (25.2%) or who had mild to moderate renal impairment (38.1%) were higher than in RCTs of non-vitamin K antagonist oral anticoagulants (NOACs) for acute VTE treatment (∼12–13% elderly and ∼26–29% with mild or moderate renal impairment) (from analyses of the RE-COVER trials; Hokusai-VTE and AMPLIFY). Older patients and those with renal impairment were more often female and were more likely to have comorbidities than the younger or normal renal function groups (Table). At the time of hospital discharge or 14 days after diagnosis, whichever was later, the majority was treated with NOACs (54%). Vitamin K antagonists were prescribed to approximately 1 in 5 patients. The use of NOACs decreased with worsening renal function, whereas the proportions treated with parenteral anticoagulation alone increased in the moderate renal impairment group compared with patients with normal renal function.

Conclusion

The population treated for acute VTE in routine clinical practice includes more elderly and renally impaired patients than represented in RCTs. These baseline data provide a snapshot of patient characteristics and patterns of anticoagulant therapy.

Acknowledgement/Funding

Funded by Boehringer Ingelheim

P3848Baseline profile of patients treated for acute venous thromboembolism (VTE) in routine clinical practice according to VTE location in the RE-COVERY DVT/PE global cohort study

Background

In contrast to randomized clinical trials, observational studies provide the opportunity to evaluate routine practice in real-world patient populations.

Purpose

Using data from the RE-COVERY DVT/PE global observational study (enrollment January 2016 to May 2017), we have explored patient characteristics and anticoagulant treatment patterns in subgroups defined according to the type and location (proximal or distal lower limb) of acute venous thromboembolism (VTE).

Methods

Baseline patient characteristics, details of hospitalization and choice of anticoagulant therapy were tabulated descriptively for three groups of patients according to the type and location of their index VTE: pulmonary embolism (PE) (± any deep vein thrombosis; DVT); proximal (± distal) lower limb DVT, including the iliac vein; or distal lower limb DVT. Anticoagulant therapy at baseline and at hospital discharge or 14 days after diagnosis (whichever was later) was recorded.

Results

Of the 6122 eligible patients, 324 who had DVT at locations other than the lower limb and no PE were excluded from this analysis (as a key objective was to compare subgroups with DVT in the lower extremities according to whether the location was distal alone or involved the proximal segment). The remaining 5798 patients had either distal DVT (17.7%), proximal (± distal) DVT (40.0%) or PE (± any DVT) (42.3%) (Table). The likelihood of being diagnosed in an emergency department and of being hospitalized for VTE increased in line with the seriousness of the index event (distal DVT to PE). There were corresponding increases in age and the proportion of patients with comorbidities and/or medical history such as hypertension, diabetes mellitus or active cancer across these subgroups. At the time of hospital discharge or 14 days after diagnosis, whichever was later, non-vitamin K antagonist oral anticoagulants were the most commonly used anticoagulants (53% of patients in the PE group and 55–56% in the two DVT groups). The use of parenteral anticoagulant therapy alone appeared to be lower in the PE group than in the DVT groups, but the total use of parenteral therapy (alone or prior to oral anticoagulation) increased across groups from distal DVT (67%) to proximal DVT (74%) to PE (79%).

Conclusion

These data provide an insight into the potential differences in patient characteristics and treatment patterns among patients with PE, proximal/iliac lower limb DVT or distal lower limb DVT.

Acknowledgement/Funding

Funded by Boehringer Ingelheim

P3711Impact of peri-device leakage after interventional occlusion of the left atrial appendage: Results from the ORIGINAL registry (saxOnian RegIstry analyzinG and followINg left atrial Appendage cLosure)

Background

Oral anticoagulation for prophylaxis of central and peripheral embolisation is limited in its use in patients with atrial fibrillation (AF) and bleeding events. As an alternative to anticoagulation, the interventional closure of the left atrial appendage (LAAO) is available. A common clinical dilemma is the treatment of patients with potential peri-device leakage following LAA occlusion. The specific definition of the severity of the leak and the long-term clinical implications have not yet been sufficiently investigated.

Methods

The multi-centre ORIGINAL registry was initiated 2014. The aim of this registry is to analyze the safety and efficacy of the procedure in patients with a high risk of bleeding in everyday clinical practice and to evaluate hemorrhagic and thromboemb. events in the long term follow-up. Patients with an indication for LAA occl. were included in the registry after informed consent. The impl., follow-up and anticoagulation regimens are performed according to the standard of the participating centers. 521 patients with AF underwent an implantation of an LAA closure device between Jul. 2014 and Nov. 2018. A mean follow-up of 463 days could be reached in 386 patients.

Results

The periprocedural complication rate was 3.8% of which 5 patients experienced pericardial effusion (successful treatment with pericardial puncture or surgical), 2 patients had periprocedural stroke and 1 patient suffered from air embolism. In 27 patients a peri-device flow due to incomplete occlusion was detected by TEE (5.4% of the implantations). The size ranged between 1 and 8 mm (mean 2.28 mm (SD=2.11)). The eccentricity index (EI) of the LAA in these patients was 1.22 (SD 0.17), and thus the LAA rather oval, while those LAA without leakage tend to be more circular (EI 1.08 with SD=0.17). 2 of the patients with leakage (7.4%) experienced stroke or peripheral embolism, respectively. The annual risk for stroke/TIA/peripheral embolism of these patients was 5.84%, the annual risk of the patients without leakage was 2.04%. Patients with a leakage >6 mm were treated with rivaroxaban in full therapeutic dosage. One patient underwent an additional procedure.

Conclusion

The evaluation and management of para-device leakage after an interventional LAA occlusion represents a challenge. Currently, limited data are available on the optimal strategy. Those data indicate that residual peri-device flow into the LAA after percutaneous closure with the Watchman device represents no cause for alarm. However, our data suggest, that patients with peridevice leak might be at a higher risk of thromboembolic events. Furthermore, it could be shown, that these patients had rather oval ostium of the LAA, while those LAA without leakage tend to be more circular. This implicates the importance of advanced imaging methods, such as 3D-TEE, which are capable to precisely determine the size of the LAA and the degree of its circularity.

Acknowledgement/Funding

None

284Outcomes after left atrial appendage occlusion with AMPLATZER Amulet and WATCHMAN device: Results from the ORIGINAL registry (saxOnian RegIstry analyzinG and followINg left atrial Appendage cLosure)

Aims

Left atrial appendage occlusion (LAAO) is a therapeutic option for patients with non-valvular atrial fibrillation (NVAF) and high risk of bleeding. This study reports outcomes of patients enrolled in the prospective multicentre, investigator initiated real life registry in the Free State of Saxony (saxOnian RegIstry analyzinG and followINg left atrial Appendage cLosure).

Methods and results

Data of all consecutive 521 patients (64.7% adult males, 35.3% adult females, mean age: 75.1 (SD 7.9) years with non-valvular atrial fibrillation undergoing interventional left atrial appendage occlusion procedure in the ORIGINAL prospective registry were analysed. The CHA2DS2-VASc and HAS-BLED scores were 4.3 (SD 1.5) and 3.7 (SD 1.1), respectively. 78.9% of the patients had a history of bleeding. 89.3% of the patients were considered as non-eligible for long term oral anticoagulation. A left atrial appendage occlusion device was successfully implanted in 97.5% of cases. A mean follow-up of 463 days could be reached in 386 patients. Among these, the distribution of the follow-up length reached was as follows: 1 year 205, 2 years 118, 3 years 65 and 4 years 17 patients. In the follow-up the annual frequency of stroke was very low (0.4%), which resulted in the 4.98% absolute risk reduction in the amount of thromboembolic strokes, which would have been expected according to the calculated CHA2DS2-VASc score in the hypothetic group not receiving any anticoagulant therapy. The occurrence of major and minor bleeding in the follow-up was 1.55% and 3.37% respectively.

Conclusions

In this prospective multicentre study we included the patients who are at high risk of stroke and bleeding. The annual ischemic stroke rate was 0.4%, the LAA could be sealed in 97.5%. Six months after the LAA closure only 3.63% of all patients were further on treated using oral anticoagulation. Considering the stroke reduction rates, the implantation of an LAAO device proves to be effective and safe in the clinical routine in the studied population.

Acknowledgement/Funding

None

[Management of pre-existing anticoagulation for timely treatment of proximal femoral fractures]

Proximal femoral fractures are urgent indications for surgery. In cases of delayed surgical treatment more than 48 h after hospital admittance, increased rates of general complications, local complications and mortality have been proven. Since 2015, the quality target for the external quality assurance by order of the Federal Joint Committee (G-BA) is surgical treatment within 24 h after hospital admittance for osteosynthesis and within 48 h for joint replacement. The foundations for these time intervals are the S2e guidelines for the treatment of femoral neck fractures of adults from the German Society of Trauma Surgery (DGU) and the Austrian Society of Trauma Surgery (ÖGU) and several other international guidelines. The distinction of the temporal specifications between osteosynthesis and joint replacement in Germany is unusual in comparison with other countries. For 15% of each group of patients a prolonged preoperative preparation is accepted. In the structured dialog within the external quality management anticoagulants are quoted as the most frequent reason for delayed surgery. The present review provides a way to achieve compliance with statutory provisions, to minimize the risks of both bleeding and thromboembolism and to achieve surgical treatment of proximal femoral fractures within the agreed time limit.

Therapie des Antiphosphoplidsyndrom (APS) mit DOAK

Das Antiphospholipid-Syndrom ist eine der schwerwiegendsten thrombophilen Störungen, die nicht nur zu rezidivierenden venösen, sondern auch zu arteriellen Thromboembolien sowie Schwangerschaftskomplikationen führen kann. Zusammen mit dem klinischen Bild ist das APS durch spezifische Laborbefunde charakterisiert: 1. Lupus Antikoagulans (LA), 2. Anticardiolipin-Antikörper (ACA), 3. β2-Glykoprotein I-Antikörper (β2GPI-AK). Alle Testergebnisse müssen nach 12 Wochen bestätigt werden. Sind alle drei Testgruppen positiv, besteht das höchste thrombotische Risiko. Beachtet werden muss, dass LA-Tests unter UFH, VKA oder DOAKs falsch positiv ausfallen können; bei DOAKs scheint die Zugabe von Absorbern nach Blutentnahme zuverlässige Ergebnisse zu liefern.

Eine Vergleichsstudie (TRAPS) zwischen VKA und dem DOAK Rivaroxaban mit ausschliesslich 3-fach positiven Hochrisiko-Patienten wurde vorzeitig abgebrochen, wegen erhöhter Ereignisraten unter Rivaroxaban [19 % zumeist arterielle Ereignisse versus 3 % unter Warfarin (HR 7.4; 1.7–32.9)]. Ein daraufhin herausgegebener Rote-Hand-Brief warnt vor der Anwendung von DOAKs bei Patienten mit APS, insbesondere bei Hoch-Risiko- (3-fach positiven) Patienten, und empfiehlt die Überprüfung einer laufenden DOAK-Therapie und eine mögliche Umstellung auf VKA, insbesondere bei Hoch-Risiko-Patienten. Als Fazit soll 1. bei klinischem Verdacht eine sorgfältige APS-Diagnostik erfolgen. Viele Patienten haben aufgrund von inadäquater Diagnostik wahrscheinlich gar kein APS und können bei venöser Thromboembolie adäquat ein DOAK erhalten.

2. Bei einfach- oder zweifach-positiven Antiphospholipid-AK Tests ohne LA besteht ein vergleichbar niedriges Thromboserisiko; auch hier kann möglicherweise ebenfalls mit DOAKs behandelt werden, wenn venöse Thrombosen vorliegen – ausreichende Daten liegen noch nicht vor, aber Metaanalysen legen dies nahe. 3. Patienten mit Positivität in allen 3 APS-Tests und APS-Patienten mit arteriellen Thromboembolien haben ein sehr hohes Risiko. Die TRAPS-Studie zeigt, dass diese Patienten nicht mit DOAKs, sondern mit einem VKA behandelt werden sollen.

Vergleich der Response gegenüber aktiviertem Protein C in unterschiedlichen Testsystemen mit dem Ergebnis der Faktor-V-Genotypisierung

Bei 157 Patienten und 14 Familienangehörigen wurde die Response gegenüber aktiviertem Protein C (APC) in drei unterschiedlichen Tests bestimmt und mit dem Ergebnis der Genotypisierung verglichen. Die Ermittlung der laboreigenen Referenzwerte erfolgte aus Plasmaproben von 96 anamnestisch gesunden Probanden mit normalem Genotyp. Zur Bestimmung der APC-Response wurden folgende Testsysteme eingesetzt: Test Immunochrom® APC-Response, Coatest® APC™ Resistance und Coatest® APC™ Resistance mit einer Verdünnung des Plasmas mit Faktor-V-Mangelplasma. Die Testmodifikation mit Verdünnung des Patientenplasmas mit Faktor-V-Mangelplasma erbrachte mit Ausnahme von Patienten unter Vollheparinisierung eine gute Trennung zwischen Wildtyp und Faktor-V-Mutation. Dieser Test reduziert jedoch offensichtlich die Aussage auf die Faktor-V-Mutation. Der Test Immunochrom® APC-Response zeigte unabhängig von einer Antikoagulation eine gute Übereinstimmung mit dem Ergebnis der Genotypisierung. Obwohl ein großer Teil der APC-Resistenz assoziiert ist mit einer Mutation im Faktor-V-Gen (Leiden-Mutation) sind beide Begriffe nicht synonym. Pathologische Ratios bei Patienten mit einem Wildtyp unterstreichen die Notwendigkeit zur Bestimmung der funktionellen Response und des Genotypes, ihre Ursache bedarf weiterer Abklärung.

Stationäre und ambulante Thromboembolieprophylaxe in der Chirurgie und der perioperativen Medizin

Präambel: Alle aufgeführten medizinischen Fachgesellschaften haben sich zusammengefunden, um die früheren verschiedenen Empfehlungen zur Thromboembolieprophylaxe zu aktualisieren und in einer gemeinsamen »Leitlinie zur stationären und ambulanten Thromboembolieprophylaxe in der perioperativen Medizin« zusammenzufassen. Dazu wurden in einem ersten Schritt durch eine Konsensuskonferenz mit nominalem Gruppenprozess die früheren Empfehlungen (Fassung vom Juni 2000) überarbeitet (S2-Leitlinie). Dies erschien notwendig, um neue Therapieprinzipien und neu zugelassene Medikamente zu berücksichtigen. Als nächster Schritt erfolgt die Weiterentwicklung der vorliegenden Leitlinie nach der Vorgaben der 3. Stufe der Leitlinienentwicklung der AWMF (S3-Leitlinie).

Abschätzung des Thromboserisikos bei internistischen Patienten

Bei einem thromboembolischen Ereignis handelt es sich möglicherweise um eine vermeidbare Komplikation, wenn das Risiko prospektiv erkennbar ist. Die richtige Einschätzung des individuellen Risikos ist deshalb von herausragender klinischer Bedeutung, bei internistischen Patienten wegen der Komplexität und Multimorbidität älterer Patienten jedoch schwierig. Bei nicht chirurgischen Patienten ist das individuelle Thromboserisiko definiert als Summe aus expositionellen und dispositionellen Risikofaktoren, die nach evidenzbasierter Studienlage gewichtet und in ein Risikoschema umgesetzt werden. In ein praxisnahes und alltagstaugliches Risikoschema können nicht alle klinischen Situationen aufgenommen werden, jedoch erlauben die Schemata in dieser Arbeit die flexible Anwendung und Anpassung an die individuelle Patientensituation in Klinik und ambulanter Versorgung. Damit soll ermöglicht werden, dass der Arzt eine begründete Ja/Nein-Entscheidung zur Thromboseprophylaxe treffen kann.

Therapie mit Dabigatran

Summary Dabigatran, an oral, reversible direct factor IIa inhibitor, is approved in Europe for stroke prevention in atrial fibrillation and for the prevention of venous thromboembolism after elective hip and knee replacement. In contrast to vitamin K antagonists, a routine coagulation monitoring during the treatment with dabigatran etexilate is not necessary. However, in specific clinical situations such as invasive emergency procedures or serious haemorrhage, the actual anticoagulant status of dabigatran may be of importance for the treating clinician and can be assessed by clotting tests (aPTT, TT, ECT). The diluted thrombin time test (Hemoclot®), which is specifically calibrated for dabigatran, is useful for quantitative determination of the dabigatran serum concentration. In general, discontinuation of dabigatran etexilate 24 hours before standard elective surgery is sufficient to normalise the bleeding risk in patients with normal renal function. In patients with renal impairment and/or in the case of a high bleeding risk procedure the recommended duration of discontinuation is prolonged. If a bleeding episode occurs in a patient on dabigatran, further treatment should be based on the severity and localisation of the bleeding. A distinct feature of dabigatran is the possibility of effectively removing dabigatran from the circulation by haemodialysis. Recommendation: In the case of clinically minor bleedings, a delay in the administration of the next dabigatran etexilate dose is recommended. The length of the delay is based on the patient’s individual thromboembolic risk. In minor bleedings the use of prothrombin complex concentrates is not indicated. In the case of moderate or major bleedings the main focus should be on stabilising the circulation by using fluids and blood products and, if a lesion can be identified, the local treatment thereof. If time and infrastructure is available, dialysis offers an effective and fast option to remove dabigatran out of the circulation. In the incidence of severe and life threatening bleedings, an additional, more complex haemostasis management is required. Besides haemodynamic stabilisation of the circulation, administration of prothrombin complex concentrates should not be delayed. It has to be kept in mind that standard laboratory coagulation parameters may not accurately reflect the effect of prothrombin complex concentrates in patients on dabigatran. Hence the effect of the prothrombin complex concentrate should be monitored clinically and adjusted by means of onset of coagulation in vivo.

New anticoagulants

Heparins and vitamin K antagonists have been the cornerstones of anticoagulation therapy for several decades. Although they are very effective at inhibiting the coagulation process, they have several practical limitations. This was a challenge for the development of therapies that will overcome these drawbacks while matching the efficacy of the two classes of anticoagulants. Advances were achieved in the development of safer, convenient, more specific treatments, which should provide predictable anticoagulant responses and substantially improve the prevention and management of thromboembolic disorders. In the search for new agents matching the ideal anticoagulant profile, different steps in the coagulation cascade have been targeted, including direct thrombin inhibition, and inhibition of factor Xa, factor IXa, the factor Vlla-tissue factor complex and the factor Va-factor Vllla complex. The most advanced clinical development has been achieved with direct factor Xa- and factor IIa-inhibitors which may replace conventional anticoagulants for long-term prevention and treatment of venous and arterial thromboembolic complications.

Platelet activation in the presence of neutral protamine Hagedorn insulin: a new feature of antibodies against protamine/heparin complexes

Essentials Protamine (PRT) is used to stabilize insulin in neutral protamine Hagedorn (NPH) insulin. The interaction between NPH-insulin, anti-PRT/heparin antibodies and platelets was investigated. Anti-PRT/heparin antibodies activate platelets in presence of NPH-insulin dependent on heparin. Cross-reactivity seems to have no major effect on the clinical outcome of medical patients.

SUMMARY

Background Protamine (PRT) is used to stabilize insulin in neutral protamine Hagedorn (NPH) insulin, a commonly used therapeutic agent for diabetes mellitus. Immunization against PRT/heparin complexes is common in diabetic patients. Objectives To investigate the impact of NPH-insulin on the interaction between anti-PRT/heparin antibodies and platelets. Methods The interaction between NPH-insulin and anti-PRT/heparin antibodies was tested using in-house enzyme immunoassays. The ability of anti-PRT/heparin antibodies to activate platelets in the presence of NPH-insulin (and heparin) was investigated using flow cytometry. Results Twenty-one out of 80 sera containing anti-PRT/heparin IgG showed binding to NPH-insulin. Anti-PRT/heparin IgG from immunized patients bound to platelets in the presence of NPH-insulin, but not in the presence of native insulin. Anti-PRT/heparin antibodies induced P-selectin expression in the presence of NPH-insulin in a heparin-dependent way (median mean fluorescence intensity in the presence of NPH-insulin: 55, 95% confidence interval [CI] 18.7-100.5 vs. NPH-insulin and heparin: 204, 95% CI 106.5-372.8). The clinical relevance of platelet-activating anti-PRT/heparin antibodies was assessed by investigating a multicenter study cohort of 332 acutely ill medical patients who received heparin. None of the 21 patients with anti-PRT/heparin IgG developed thrombocytopenia or thromboembolic complications. Conclusions Anti-PRT/heparin antibodies activate platelets in the presence of NPH-insulin in a heparin-dependent way. However, results from our preliminary study indicate no major impact of these antibodies on the clinical outcome in medical patients receiving heparin, particularly on thromboembolic complications.

[Diseases of the peripheral vestibular system: contribution of ENT medical diagnostics and therapy]

The most common types of vertigo caused by diseases of the peripheral vestibular system are benign paroxysmal positional vertigo (BPPV), Meniere's disease and vestibular neuritis. A thorough examination of the medical history and clinical examination are usually sufficient for the differential diagnostics. Treatment includes differentiated repositioning maneuvers, medicinal treatment and physiotherapy.

A prognostic score to identify low-risk outpatients with acute deep vein thrombosis in the lower limbs

BACKGROUND

No prior studies have identified which patients with deep vein thrombosis in the lower limbs are at a low risk for adverse events within the first week of therapy.

METHODS

We used data from the Registro Informatizado de la Enfermedad TromboEmbólica (RIETE) to identify patients at low risk for the composite outcome of pulmonary embolism, major bleeding, or death within the first week. We built a prognostic score and compared it with the decision to treat patients at home.

RESULTS

As of December 2013, 15,280 outpatients with deep vein thrombosis had been enrolled. Overall, 5164 patients (34%) were treated at home. Of these, 12 (0.23%) had pulmonary embolism, 8 (0.15%) bled, and 4 (0.08%) died. On multivariable analysis, chronic heart failure, recent immobility, recent bleeding, cancer, renal insufficiency, and abnormal platelet count independently predicted the risk for the composite outcome. Among 11,430 patients (75%) considered to be at low risk, 15 (0.13%) suffered pulmonary embolism, 22 (0.19%) bled, and 8 (0.07%) died. The C-statistic was 0.61 (95% confidence interval [CI], 0.57-0.65) for the decision to treat patients at home and 0.76 (95% CI, 0.72-0.79) for the score (P = .003). Net reclassification improvement was 41% (P < .001). Integrated discrimination improvement was 0.034 for the score and 0.015 for the clinical decision (P < .001).

CONCLUSIONS

Using 6 easily available variables, we identified outpatients with deep vein thrombosis at low risk for adverse events within the first week. These data may help to safely treat more patients at home. This score, however, should be validated.

[Leg discoloration]

Many patients present with discolouration of the legs or with non-ulcerating skin lesions, the most frequent causes being chronic venous insufficiency or other chronic or acute states of congestion. Erysipelas (cellulitis) is also a frequent example of a bacterial skin infection. A complex differential diagnosis arises from all types of immune-mediated skin lesions, opening up the broad spectrum of inflammatory systemic disease, such as vasculitis and sarcoidosis. Livedo like lesions and skin involvement in borreliosis are challenging to classify but of considerable clinical importance. The present review focuses on the description of underlying diseases as well as on diagnosis and differential diagnosis. Therapeutic considerations are discussed in less detail.

[Foot lesions]

The foot is the target organ of a variety of internal diseases. Of upmost importance is the diabetic foot syndrome (DFS). Its complex pathophysiology is driven by the diabetic neuropathy, a vastly worsening effect is contributed by infection and ischemia. Seemingly localised lesions have the potential for phlegmone and septicaemia if not diagnosed and drained early. The acral lesions of peripheral artery occlusive disease (PAOD) have unique features as well. However, their life-threatening potential is lower than that of DFS even if the limb is critical. Notably, isolated foot lesions with a mere venous cause may arise from insufficient perforator veins; the accompanying areas of haemosiderosis will lead the diagnostic path. Cholesterol embolization (blue toe syndrome, trash foot) elicits a unique clinical picture and will become more frequent with increasing numbers of catheter-based procedures. Finally, descriptions are given of podagra and of foot mycosis as disease entities not linked to perfusion. The present review focuses on the depiction of disease and its diagnosis, leaving therapeutic considerations untouched.

D-dimer as a predictor of venous thromboembolism in acutely ill, hospitalized patients: a subanalysis of the randomized controlled MAGELLAN trial

BACKGROUND

D-dimer concentrations have not been evaluated extensively as a predictor of increased venous thromboembolism (VTE) risk in acutely ill, hospitalized medical patients.

OBJECTIVES

To analyze the relationships between D-dimer concentration, VTE and bleeding in the MAGELLAN trial (NCT00571649).

PATIENTS/METHODS

This was a multicenter, randomized, controlled trial. Patients aged ≥ 40 years, hospitalized for acute medical illnesses with risk factors for VTE received subcutaneous enoxaparin 40 mg once daily for 10 ± 4 days then placebo up to day 35, or oral rivaroxaban 10 mg once daily for 35 ± 4 days. Patients (n = 7581) were grouped by baseline D-dimer ≤ 2 × or > 2 × the upper limit of normal. VTE and major plus non-major clinically relevant bleeding were recorded at day 10, day 35, and between days 11 and 35.

RESULTS

The frequency of VTE was 3.5-fold greater in patients with high D-dimer concentrations. Multivariate analysis showed that D-dimer was an independent predictor of the risk of VTE (odds ratio 2.29 [95% confidence interval 1.75-2.98]), and had a similar association to established risk factors for VTE, for example cancer and advanced age. In the high D-dimer group, rivaroxaban was non-inferior to enoxaparin at day 10 and, unlike the low D-dimer group, superior to placebo at day 35 (P < 0.001) and days 11-35 (P < 0.001). In both groups, bleeding outcomes favored enoxaparin/placebo.

CONCLUSIONS

Elevated baseline D-dimer concentrations may identify acutely ill, hospitalized medical patients at high risk of VTE for whom extended anticoagulant prophylaxis may provide greater benefit than for those with low D-dimer concentrations.

[Leg pain]

Leg pain is a very common complaint in clinical medicine which deserves thorough investigation. All tissues of the lower leg are able to cause pain, each of them by different pathomechanisms. In the current review, all the different types of tissue, i.e., spine, neural plexus, peripheral nerves, muscles, and vasculature, are systematically covered. The different disease entities are explained in terms of pathophysiology and clinical picture. Diagnostic measures and pathways are sketched, as well as therapeutic approaches in some instances. Diseases of the bone and joint are omitted since they are the subject of orthopedic surgery.

Isolated distal deep vein thrombosis: what we know and what we are doing

Thromboses that are restricted to the infra-popliteal deep veins of the lower limbs (isolated distal deep vein thrombosis, IDDVT) are frequently diagnosed in subjects with suspected pulmonary embolism (PE; 7–10%) or DVT(4–15%), accounting for 31–56% of all diagnosed leg DVTs. Despite their frequency, IDDVTs still remain one of the most debated issues in the field of venous thromboembolism (VTE). Conflicting clinical results have resulted in differing opinions on the need to test for IDDVTs and how to treat them. Due to discordant results, the real risk of IDDVT-associated PE is not well established. IDDVTs are associated with (i) lower risk of recurrence when compared with other VTEs, and (ii) fewer late sequelae than proximal DVT. Diagnosis of IDDVT is based on ultrasound examination of all calf veins, which is more operator-dependent and less sensitive than proximal vein examination. A series of studies has shown, however, that a single complete ultrasound strategy in symptomatic patients has comparable clinical results to serial proximal ultrasound, allowing approximately 15% better DVT diagnosis. Optimal treatment of IDDVT is still controversial. Guidelines recommend anticoagulation for 12 weeks, although 6 weeks may be sufficient. There is, however, insufficient data to support the diagnosis and treatment of all IDDVTs, and the necessary criteria to identify subjects at higher risk of complication are lacking. It also seems likely that different approaches may be better for unprovoked or secondary events and for deep or muscle veins. Specifically designed and adequately powered clinical studies addressing the issue of IDDVT need to be urgently undertaken.

Central adjudication of venous ultrasound in VTE screening trials: reasons for failure

BACKGROUND

The accuracy of screening ultrasound for venous thrombosis in asymptomatic patients is still a matter of debate. The VENUS study evaluated the accuracy of centrally adjudicated venous ultrasound against venography in patients after major orthopedic surgery and found the sensitivity of ultrasound to be poor for both proximal and distal deep vein thrombus (DVT).

OBJECTIVES

To evaluate whether thrombus characteristics such as location or size influence the diagnostic performance of centrally adjudicated venous ultrasound.

METHODS

All false negative sonograms of the VENUS study were re-evaluated against the corresponding venograms. Discrepancies were categorized into types of diagnostic failures. Within these categories, thrombus characteristics such as location, length or size of thrombus were evaluated.

RESULTS

One hundred and twelve pairs of discrepant ultrasound and venography documents were compared with 28 pairs with concordant results. Discrepancies were caused by local documentation failure (37.5%), failure of the ultrasound method (43.7%) and failure of the central adjudication process (18.7%). The overall size of thrombi was small, which caused about 40% of all sonographic failures with a detection threshold of five Marder points, a thrombus length of 9.5 cm and a number of 3.5 pathological compression manoeuvres. Proximal or distal location of DVT did not affect thrombus detection.

CONCLUSION

If centrally adjudicated ultrasound is to be used in future VTE screening trials, training of local sonographers and central adjudicators needs to be intensified, because asymptomatic DVTs seem to be small and ultrasound sensitivity depends on the number of pathological compression manoeuvres documented in the ultrasound document. In contrast, distal or proximal thrombus location itself does not influence sensitivity.

Heparin-induced thrombocytopenia: towards standardization of platelet factor 4/heparin antigen tests

BACKGROUND

Laboratory confirmation of heparin-induced thrombocytopenia (HIT) is based on detection of heparin-dependent platelet-activating antibodies. Platelet factor 4 (PF4)/heparin enzyme-immunoassays (EIA) are a widely available surrogate for platelet-activating antibodies.

OBJECTIVE

Defining the optical density (OD) reactivity profiles of a PF4/heparin EIA in reference subject and patient populations and the correlation of the EIA results (expressed in OD units) with the prevalence of platelet-activating antibodies.

PATIENTS/METHODS

Using quantile regression we determined the 97.5th percentile of PF4/heparin-immunoglobulin G (IgG) EIA reactivities in non-heparin-treated individuals [blood donors (n = 935)] and patients before heparin therapy (n = 1207). In patients with suspected HIT, we compared the correlation of EIA-IgG reactivities (Greifswald laboratory; n = 2821) and the heparin-induced platelet activation assay (HIPA) with the correlation of reactivities of another EIA-IgG (McMaster laboratory; n = 1956) with the serotonin-release assay (SRA).

RESULTS

PF4/heparin-IgG EIA OD reactivities had a lower OD 97.5th percentile in blood donors compared with patient groups before heparin treatment (P < 0.001). The percentage of sera testing positive in the functional assays strongly correlated with PF4/heparin-IgG EIA OD reactivities in both laboratories with very similar results (correlation coefficient > 0.9) when normalized OD ranges (maximum OD divided by 10) were used instead of absolute OD values.

CONCLUSIONS

Results of PF4/heparin-IgG EIA should not be reported as only positive or negative as there is no single acceptable cut-off value. Instead, reporting PF4/heparin-IgG EIA OD results in ranges allows for risk-stratified prediction for presence of platelet-activating antibodies. Use of normalized OD ranges permits a standardized approach for inter-laboratory comparisons.

[Diagnostic value of color-coded Doppler sonography in neuro-otologic disorders]

PURPOSE

The successful introduction of Doppler and Color-Coded Doppler Sonography (CCDS) in the field of Otorhinolaryngology has improved the diagnostic sonographic value for several diseases of the head and neck region, e. g. in hemangiomas and vascular malformations. The diagnostic value of CCDS for examination of the extracranial brain supplying vessels in combination with neuro-otologic disorders is still under controversial discussion.

MATERIALS AND METHODS

We investigated the diagnostic CCDS findings for 215 patients suffering from different neuro-otologic disorders. All patients were classified into 4 groups according to the different disorder entity (sudden deafness, tinnitus, vestibular neuropathy, combined diagnosis). The frequency of pathologic CCDS findings was correlated with the different groups using sonographic parameters such as atherosclerosis, stenosis and intima-media thickness.

RESULTS

Classification of the disorder entities led to the following distribution: Sudden deafness group (85 patients; 40 %), Tinnitus group (44 patients; 20 %), Vestibular neuropathy group (41 patients; 19 %), Combined diagnosis group (45 patients; 21 %). Sonographic evaluation of atherosclerosis was possible in 76 cases (35 %), changes of the intima-media thickness were observed in 43 cases (20 %) while proof of stenoses was identified in 15 cases (7 %). The evaluation of plaque formation (atherosclerosis) in the sudden deafness group was significantly higher (p < 0.01) than in all other groups although the combined diagnosis group demonstrated certain tendencies (p < 0.08) without significant correlation.

CONCLUSION

Our results reinforce the hypothesis of a vascular genesis of sudden deafness and seem to offer the possibility of sonographic differentiation between neuro-otologic disorder entities by use of CCDS. In contrast, it seems that the role of CCDS is negligible for individual diagnostic purposes.

[Fibrinolytic therapy]

Fibrinolytic therapy still is a keystone in the therapeutic approach of acute occlusion in different vascular regions. However, before starting fibrinolytic therapy an evidence-based risk assessment is necessary. This article presents the most common fibrinolytic agents as well as evidences and recommendations for fibrinolytic therapy of different vascular regions.

Fibrinolytische Therapie

Die fibrinolytische Therapie ist unverändert ein zentraler Therapieansatz bei akuten Verschlüssen verschiedener Gefäßregionen; allerdings ist vor dem Beginn einer Lysetherapie eine evidenzbasierte sorgfältige Risiko/Nutzen-Abwägung unumgänglich. Dieser Beitrag stellt die gebräuchlichen Fibrinolytika sowie Datenlage und die aktuellen Empfehlungen für Lysetherapie in den wichtigsten Gefäßregionen vor.

New anticoagulants: from bench to bedside

Heparins and vitamin K antagonists have been the cornerstones of anticoagulation therapy for several decades. Although they are very effective at inhibiting the coagulation process, they have several practical limitations. This was a challenge for the development of therapies that will overcome these drawbacks while matching the efficacy of the two classes of anticoagulants. Advances were achieved in the development of safer, convenient, more specific treatments, which should provide predictable anticoagulant responses and substantially improve the prevention and management of thromboembolic disorders. In the search for new agents matching the ideal anticoagulant profile, different steps in the coagulation cascade have been targeted, including direct thrombin inhibition, and inhibition of factor Xa, factor IXa, the factor Vlla-tissue factor complex and the factor Va-factor Vllla complex. The most advanced clinical development has been achieved with direct factor Xa- and factor IIa-inhibitors which may replace conventional anticoagulants for long-term prevention and treatment of venous and arterial thromboembolic complications.

Complete ulcer healing as primary endpoint in studies on critical limb ischemia? A critical reappraisal

OBJECTIVES

Although complete ulcer healing is the mandatory primary efficacy criterion in current European guidelines for drug trials in critical limb ischemia (CLI), the appropriateness of this endpoint has been questioned for some time. We carried out a systematic review to assess the value of this endpoint in studies on reconstructive measures, considered to be the standard of care for CLI.

METHODS

A computerized literature search (1985-2005) was performed to track down clinical studies on endovascular and surgical interventions by using the search terms CLI and ulcer healing and their synonyms.

RESULTS

1,914 papers on revascularization in CLI were identified. Complete ulcer healing was reported in 17 studies (0.9%). Among these, there were no randomized controlled trials, five prospective cohorts on endovascular procedures, and six retrospective cohorts for endovascular and surgical procedures, respectively. If healing rates or time to ulcer healing were available, they differed greatly between the studies without consistent correlation to types of therapy.

CONCLUSIONS

In past and current literature, complete ulcer healing is not a consistently reported criterion for success of revascularization in CLI. Thus, its appropriateness for efficacy assessment of drug studies in CLI patients has to be questioned.

Matrix metalloproteinase 2 polymorphisms in a caucasian population with abdominal aortic aneurysm

BACKGROUND

The formation of sporadic abdominal aortic aneurysm (AAA) is explained by remodeling of the extracellular matrix (ECM) and breakdown of structural components of the vascular wall. Matrix metalloproteinase 2 (MMP2) is one of the principal matrix-degrading proteases and is known to play a major role in the remodeling of the extracellular matrix in arterial vessels. Increased MMP2 expression in the extracellular matrix of the walls of AAAs has been shown in several studies. To investigate the possible impact of genetic variants of the MMP2 gene in the etiology of AAA, we conducted this case-control study.

PATIENTS AND METHODS

We analyzed MMP2 single-nucleotide polymorphisms (SNPs) in 51 patients with AAA and 48 controls. Differences in genotype and allele frequencies of identified polymorphisms were determined after sequencing the entire coding region and three selected parts of the promoter.

RESULTS

Eighteen polymorphisms were identified, 6 of which are newly described, with 3 located in the introns (c.IVS1+31C>G, c.IVS7-18G>A, c.IVS10+26C>T) and 3 located in the coding region (c.124G>A, c.1368C>T, c.1860C>T). There were no statistically significant differences in genotype or allele frequencies between the two groups.

CONCLUSIONS

Our analysis of the entire coding region and three parts of the promoter of the MMP2 gene failed to show an association between genetic polymorphisms and AAA, suggesting that variations in the MMP2 gene do not contribute to the development of AAA.

The influence of downstream arterial perfusion parameters on Doppler pulsatility index and resistance index in an in-vitro perfusion model

Background: To investigate in vitro how downstream perfusion parameters influence pulsatility index (PI), resistance index (RI) and their constituting Doppler velocities. Materials and methods: We analyzed the influence of resistance, compliance, reflection coefficient and input impedance on PI and RI in an in-vitro model of arterial flow. Results: The nominators of PI and RI were determined by resistance. The numerators were determined by compliance and by the reflection coefficient. There were close relationships of PI and RI with resistance under the condition of constant compliance, but not when compliance was variable. Conclusion: PI and RI consist of velocity terms which are independently influenced by different parameters of impedance: compliance, reflection coefficient and resistance. These findings explain the contradictory results reported for the relationship between the indices and peripheral resistance in studies where compliance and reflection effects were not considered.

[Fibrinolytic therapy]

Fibrinolytic therapy still is a keystone in the therapeutic approach of acute occlusion in different vascular regions. However, before starting fibrinolytic therapy an evidence-based risk assessment is necessary. This article presents the most common fibrinolytic agents as well as evidences and recommendations for fibrinolytic therapy of different vascular regions.