D-dimer and fibrinogen indicate ischemic risk in patients with atrial fibrillation after percutaneous coronary intervention

BACKGROUND

This study aimed to evaluate the association of antiphospholipid antibodies (aPL) and conventional markers of coagulation with ischemic and bleeding risk in patients with atrial fibrillation (AF) undergoing percutaneous coronary intervention (PCI).

METHODS

In this prospective two-center observational cohort study, patients with AF and an indication for oral anticoagulation (OAC) were enrolled after PCI. Blood was drawn on day 1-3 after PCI. Dilute Russell's viper venom time was used to determine lupus anticoagulant (LA) in OAC-free plasma. Anti-cardiolipin (aCL) IgG, IgM, and anti-β2-Glycoprotein 1 (aβ2GP1) IgG were analyzed by enzyme-linked immunosorbent assay (ELISA). Fibrinogen (FIB), d-dimer, and prothrombin fragment 1 and 2 (PF 1 + 2) were measured in citrated plasma. The primary ischemic outcome was time to major adverse cardiovascular events (MACE; death, myocardial infarction, or stroke) assessed at 6 months. Bleeding was defined according to International Society on Thrombosis and Haemostasis.

RESULTS

158 patients were enrolled between May 2020 and May 2021 on day 1-3 after PCI. The median age was 78 years (interquartile range [IQR] 72-82), 111 (70%) were male, and 39 (25%) presented with acute coronary syndrome. D-dimer was elevated in 74 (47%) patients, FIB was increased in 40 (25%) and PF1 + 2 in 68 (43%) patients. 32 (20%) patients had ≥ 1 antiphospholipid antibody elevated (aPL; LA: 19 [12%], aCL: 14 [9%], aβ2GP1: 2 [1%]). The presence of aPL was neither significantly associated with MACE (HR 1.46, 95% CI [0.39-5.49], p = 0.579), nor bleeding (HR 1.07 [0.30-3.84], p = 0.917). Elevated d-dimer was significantly associated with higher risk for MACE (HR 5.06 [1.09-23.41], p = 0.038) and major bleeding (HR 7.04 [1.58-31.47], p = 0.011). Elevated D-dimer increased the predictive capacity of HAS-BLED for major bleedings (HAS-BLED: AUC 0.71 [0.60-0.83] vs. HAS-BLED + d-dimer: AUC 0.79 [0.70-0.88]; p = 0.025). Increased levels of FIB were associated with higher risk for MACE (HR 3.65 [1.11-11.96], p = 0.033).

CONCLUSION

Biomarkers of coagulation might be suitable to assess ischemic and bleeding risk in patients with AF following PCI.

Low on-clopidogrel ADP- and TRAP-6-induced platelet aggregation in patients with atrial fibrillation undergoing percutaneous coronary intervention: an observational pilot study

High on-clopidogrel platelet reactivity (HPR) associates with ischemic risk in patients after percutaneous intervention (PCI). This study aimed to evaluate the association of HPR as assessed by multiple electrode aggregometry (MEA) with ischemic, thromboembolic, and bleeding risk in patients with atrial fibrillation (AF) undergoing PCI. Patients with AF and an indication for oral anticoagulation (OAC) were included in this prospective cohort study on day 1-3 after PCI. Platelet aggregation [U] was analyzed by MEA. HPR and low platelet reactivity (LPR) were defined as ADP-induced aggregation ≥ 46 U and ≤ 18 U, respectively. TRAP-6-induced aggregation reference was 94-156 U. The primary outcome was time to all-cause death, myocardial infarction, or stroke at 6 months. The secondary outcome was time to non-major clinically relevant bleedings or major bleedings. 159 patients were enrolled between May 2020 and May 2021. The median age was 78 years (interquartile range 72-82) and 111 (70%) were male. Median ADP- and TRAP-induced aggregation were 12 (6-17) and 49 (35-68) U, respectively. 147 (93%) patients had a low overall aggregability. HPR was detected in 2 patients (1%) and 125 (79%) had LPR. ADP-induced aggregation did not significantly associate with the primary outcome (r = 0.081, p = 0.309) but correlated inversely with bleeding risk (r = - 0.201, p = 0.011). HPR status as assessed by MEA among patients with AF after PCI was rare and overall aggregability was low. Conventional cut-off values for HPR might be inappropriate for these patients. ADP-induced aggregation might be helpful to identify patients at risk for bleeding.

Comparison of phenprocoumon with direct oral anticoagulants in catheter ablation of atrial fibrillation

Aims

In patients undergoing catheter ablation for atrial fibrillation (AF), direct oral anticoagulants (DOACs) are as effective and safe as the vitamin K antagonist (VKA) warfarin. Phenprocoumon has a different pharmacokinetic profile compared with warfarin and is the most used VKA in Germany. The aim of the study was to compare DOAC with phenprocoumon.

Methods and results

In this retrospective single-centre cohort study, 1735 patients who underwent 2219 consecutive catheter ablations for AF between January 2011 and May 2017 were included. All patients were in-hospital for at least 48 h after catheter ablation. The primary outcome was defined as peri-procedural thrombo-embolic events. The secondary outcome was any bleeding according to the International Society on Thrombosis and Haemostasis (ISTH). The mean age of the patients was 63.3 years. Phenprocoumon was prescribed in 929 (42%) of the cases, and in 697 (31%) dabigatran, 399 (18%) rivaroxaban, and 194 (9%) apixaban. During hospitalization, 37 (1.6%) thrombo-embolic events occurred, including 23 transient ischaemic attacks (TIAs). Compared with the use of phenoprocoumon, the use of DOAC was significantly associated with a lower thrombo-embolic risk [16 (1.2%) vs. 21 (2.2%), odds ratio (OR)], 0.5 [95% confidence interval (CI) 0.2-0.9], P = 0.04. No statistically significant association with bleeding risk was observed [phenprocomoun: 122 (13%); DOAC: 163 (12.6%); OR 0.9 (95% CI 0.7-1.2); P = 0.70]. Interruption of oral anticoagulation (OAC) was associated with an increased risk for thrombo-embolic complications [OR 2.2 (1.1-4.3); P = 0.031], and bleeding [OR 2.5 (95% CI 1.8-3.2), P = 0.001].

Conclusion

In patients undergoing catheter ablation for AF, the use of DOAC was associated with a reduced risk of thrombo-embolic events compared with phenprocoumon. Non-interrupted oral anticoagulation (OAC) therapy was associated with a reduced risk of peri-procedural thrombo-embolic and any bleeding complications.

Time from blood draw to multiple electrode aggregometry and association with platelet reactivity

Results from multiple electrode aggregometry (MEA) may vary according to pre-analytic factors. This study aimed to analyze the association of time from blood draw to MEA in patients undergoing percutaneous coronary intervention (PCI). In this observational single-center cohort study, platelet aggregation (aggregation units, U) was quantified by MEA (Multiplate Analyzer) after stimulation with adenosine diphosphate (ADP; final concentration [Fc] 6.4 μM), thrombin receptor activating peptide (TRAP; Fc 32 μM), or arachidonic acid (AA; Fc 0.5 mM) in patients treated with ASA and clopidogrel following PCI. High on-clopidogrel platelet reactivity (HPR) was defined as ADP-induced platelet aggregation ≥ 46 U. The manufacturer recommends performing the analysis within 30-180 min after blood draw. Patients were grouped according to the time from blood draw to MEA: 30-180 min, < 30 min, or > 180 min. Platelet function of 273 patients with coronary artery disease undergoing PCI with dual antiplatelet therapy was analyzed. The median age was 72 years (interquartile range, IQR 62-79) and 179 (66%) were male. Median ADP-, TRAP-, and AA-induced aggregation was 25 (IQR 18-36) U, 79 (IQR 63-96) U, and 12 (IQR 7-18) U, respectively. For those analyzed within 30-180 min from blood draw, no significant correlation of time from blood draw to MEA was observed 1) ADP (r = - 0.04, p = 0.51); 2) TRAP (r = - 0.06, p = 0.32); 3) AA (r = - 0.03, p = 0.67). In patients undergoing percutaneous coronary intervention and treated with dual antiplatelet therapy, the time from blood draw to multiple electrode aggregometry does not correlate with ADP- induced aggregation when the measurement occurred within the recommended time interval of 30-180 min after blood draw.

Association of coagulation markers and antiphospholipid antibodies with ischemic and bleeding risk in patients with atrial fibrillation undergoing percutaneous coronary intervention

Background

Antiphospholipid antibodies and other coagulation markers are associated with ischemic risk in patients with coronary artery disease without oral anticoagulation (OAC).

Aim

To assess the association of antiphospholipid antibodies (aPL) and conventional markers of coagulation with ischemic and bleeding risk in patients with atrial fibrillation (AF) undergoing percutaneous coronary intervention (PCI).

Patients and methods

In this prospective single center observational cohort study, patients with AF and an indication for OAC were enrolled after PCI. Dilute Russell's viper venom time (DRVVT) was used to determine lupus anticoagulants (LA) in direct OAC-free plasma. Anti-cardiolipin IgG (aCL), IgM and anti-beta2GP-1-IgG (aβ2GP1) were analyzed by enzyme linked immunosorbent assay (ELISA). Fibrinogen C (FIBC), d-dimers and prothrombin fragments 1 and 2 (PF1+2) were measured in citrated plasma. Immature platelet fraction (IPF [%]) and absolute (IPF abs. [103/μl]) were measured in EDTA-blood. The primary ischemic outcome was defined as time to major adverse cardiovascular events (MACE: all-cause death, myocardial infarction, or stroke) assessed at 6 months. Bleeding was defined according to the International Society of Thrombosis and Haemostasis (ISTH) and the Bleeding Academic Research Consortium (BARC).

Results

158 patients were enrolled between May 2020 and May 2021. The median age was 78 years (interquartile range, IQR 72–82), 111 (70%) were male, and 39 (25%) presented with acute coronary syndrome. All Patients were treated with clopidogrel and OAC, 145 (92%) in addition with acetylsalicylic acid (ASA). 32 patients (20%) had ≥1 antiphospholipid antibody (aPL; LA: 19 [12%], aCL: 14 [9%], aβ2GP1: 2 [1%]). D-dimers were elevated in 74 patients (47%), FIBC was increased in 40 (25%) and PF1+2 in 68 patients (43%). IPF [%] was elevated in 28 (18%) and IPF abs. [103/μl] in 11 (7%). The presence of aPL was neither significantly associated with MACE, nor with bleeding risk. Elevated d-dimers were significantly associated with higher risk for MACE (HR=5.1, 95% CI [1.1; 23.4], p=0.04), major ISTH bleeding events (HR= 6.9, 95% CI [1.5; 30.8], p=0.01) and BARC bleeding type 3 or 5 (HR=6.4, 95% CI [1.4; 28.7], p=0.02). Increased levels of FIBC were associated with risk of MACE (HR= 3.6, 95% CI [1.1; 12.0], p=0.03 (Table 1).

Conclusion

In patients with AF undergoing PCI, high levels of d-dimers and fibrinogen C indicate an increased ischemic risk. Elevated d-dimers are associated with higher risk for bleeding. aPL positivity was not significantly associated with outcome possibly due to low sample size. A combined panel of biomarkers might be suitable to assess ischemic and bleeding risk in patients with AF following PCI.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): Faculty of Medicine, Freiburg

P1860Unfractionated heparin dose and complication rate in catheter ablation of atrial fibrillation, a comparison between uninterrupted therapy with phenprocoumon and direct oral anticoagulants

Background

Catheter ablation of atrial fibrillation is known for the combining risks of thromboembolism (TE) and major bleedings. This urges a better understanding and optimization of the intraprocedural anticoagulation management. Differences in unfractionated heparin (UFH) requirements and anticoagulation time (ACT) levels between patients on different uninterrupted oral anticoagulation (OAC) agents have been studied. However, the clinical relevance, in terms of periprocedural TE and bleeding events, of UFH administration according to ACT monitoring among patients on different OAC agents, needs to be addressed.

Objective

To evaluate how the ACT monitoring and differences in intraprocedural UFH requirements among different anticoagulant agents, may translate to clinical outcome, in terms of periprocedural incidence of thromboembolic and bleeding events.

Methods

We retrospectively studied 1571 cases who underwent catheter ablation for atrial fibrillation between January 2011 and May 2017. Cases were on an uninterrupted oral OAC therapy of Vitamin K Antagonists (VKA)(713), Rivaroxaban (RG)(385), Dabigatran (DG)(260), Apixaban (AG)(192) and Edoxaban (EG)(21). First ACT measurements after the initial bolus of UFH (1ehz748.0610U), mean ACT measurements, total UFH doses/kg (Body Weight)/min (duration of procedure) and incidence of major periprocedural events were compared among the above OAC groups.

Results

The mean ACT (sec) was significantly lower in the AG and greater in the VKA (313,7±47 vs 340,5±49, p<0,001). Significantly lower UFH doses (U/kg/min) were required to reach the target ACT in VKA compared to RG, DG, AG and EG (0,69±0,4 vs 1,41±0,76; 1,42±0,7; 1,63±0,8; 1,37±0,4 respectively, p<0,001) The proportion of patients who achieved a target ACT value within 30 minutes after the fixed first UFH Bolus of 10 000 U was significantly lower in DG and AG compared to VKA, EG and RG group (51,5% and 49% vs 53%, 71,4%, and 61,8% respectively p=0,005). The incidence of periprocedural TE events and bleedings showed no significant difference among OAC groups. However, the 22 patients with a periprocedural TE event had significantly lower UFH doses (U)/ Duration of catheter ablation (min) compared to the ones without periprocedural TE (62,71±44,5 vs 94,4±66,4, p=0,026), despite equivalent mean ACT values between these two groups. Patients with a periprocedural TE had also a significantly older Age (69,6±10 vs 64±10 p=0,01, higher CHADSVASC Score (3,64±1,76 vs 2,63±1,7 p=0,006), longer duration of procedure (188,9±79,1 vs 144,9±57 p=0,0001) and higher pre-Ablation INR values (2,2±0,6 vs 1,7±0,6 p=0,002).

Conclusions

The average UFH doses required to reach the target ACT were lower in VKA than in NOAC- groups. The incidence of periprocedural TE events and bleedings was equivalent among OAC groups. Patients with TE showed a lower UFH requirement compared to no-TE group, with both groups having mean ACT ≥300 sec.

P344Does the presence of spontaneous echo contrast in TEE predict thromboembolic events during or after catheter ablation of atrial fibrillation?

Introduction

The detection of spontaneous echocontrast in the left atrium is often used as a surrogate parameter for a high cardioembolic risk. However, studies have shown that transesophageal echocardiography (TEE) guided cardioversion does not decrease the risk of thromboembolic events in comparison to long-term effective oral anticoagulation. Data to better estimate the clinical relevance of SEC 3 on the risk of thromboembolic events in catheter ablation of atrial fibrillation (AF) are missing.

Method

The cohort consisted of 1199 patients (1360 ablation procedures) who underwent TEE according to physician discretion prior to catheter ablation of paroxysmal (67%) or persistent (33%) atrial fibrillation. Mean age was 64,3 years, 35% were of female gender, 1020 (75%) procedures performed were in Cryo-technique. Almost 46% of the patient population had a CHADS-VASC score>2 and only 18% a HAS-BLED >2. Spontaneous echocontrast grade 3 (SEC 3) was seen in 135 (9.9%) TEE examinations, 1225 examinations were inconspicuous. Despite these findings, patients with SEC 3 underwent catheter ablation of AF, mainly due to disabling clinical symptoms associated with heart failure and atrial fibrillation. Catheter ablation was performed with uninterrupted oral anticoagulation in 933 cases (69%), during the ablation procedure patients received unfractionated Heparine (ACT>300s).

Results

Twenty-five strokes (1,8%) occurred in 1360 ablation procedures, eleven patients suffered from a procedure related stroke and 14 patients had a transient ischemic attack. In the group of 135 cases with SEC 3 three transient ischemic attacks occurred (2.2%) as compared to 22 embolic events (1,8%, stroke n=11, TIA n=11) in the group with inconspicuous transesophageal echocardiogram. Considering the 933 patients with uninterrupted OAC there were no thromboembolic events at all on the group with SEC 3 compared to 12 (1.4%) events on the patients presenting without SEC 3.

The type of oral anticoagulation (Vitamin K Antagonist or direct oral anticoagulant) had no effect on the overall results. Presence of SEC 3 failed to predict thromboembolic events even when the analysis was adjusted to possible explanatory variables such as age, gender, DOAC, paroxysmal or persistent AF. In contrast, interruption of oral anticoagulation prior to catheter ablation increased the risk of an embolic event (1, 3% versus 3.1%) significantly (p=0.03), specifically the detection of SEC 3 in the left atrium was a strong predictor of embolic events only in patients with interrupted oral anticoagulation (p=0.28, OR 2.4).

Conclusion

Spontaneous left atrial echocontrast seen prior to catheter ablation of atrial fibrillation does not predict perioperative thromboembolic events in patients with uninterrupted oral anticoagulation. If oral anticoagulation is interrupted for catheter intervention and spontaneous echo contrast can be detected in the left atrium, the risk of embolic events doubles.