Thrombocytopenia and declines in platelet counts: predictors of mortality and outcome after mechanical thrombectomy

Outcomes of mechanical thrombectomy in patients with acute ischemic stroke and thrombocytopenia: systematic review and meta-analysis

BACKGROUND

Mechanical Thrombectomy (MT) has improved outcomes in acute ischemic stroke (AIS) due to Large Vessel Obstruction (LVO). However, there is limited data on the safety and outcomes of MT in AIS patients with thrombocytopenia. This study aims to assess the efficacy and safety of MT in this population.

METHODS

Following the PRISMA guidelines, a comprehensive systematic review was conducted using PubMed, Embase, Web of Science, and Scopus. Studies meeting inclusion criteria underwent rigorous risk of bias assessment using the ROBINS-I tool. We compared outcomes between patients with and without thrombocytopenia undergoing MT. Using the R software version 4.3.1, meta-analyses were conducted employing random-effect models.

RESULTS

This meta-analysis encompassed data from 5 studies. Thrombocytopenic AIS patients who underwent MT (n = 974) exhibited lower rates of functional independence (OR 0.83, 95% CI 0.71-0.98; p = 0.030) compared to patients with normal platelet counts (n = 2036). In addition, the thrombocytopenic group experienced higher mortality as compared to the group with normal platelet counts (OR 1.76, 95% CI 1.26-2.45; p < 0.001). Rates of sICH were found to be similar between groups (OR 1.20, 95% CI 0.74-1.93; p = 0.456), as were rates of successful recanalization (OR 0.94, 95% CI 0.47-1.87; p = 0.863). Lastly, no significant differences were observed in procedure times between thrombocytopenic and non-thrombocytopenic groups.

CONCLUSION

As compared to patients without thrombocytopenia, thrombocytopenic AIS patients undergoing MT displayed lower functional independence and higher mortality rates, with no significant differences in sICH or successful recanalization.

Impact of thrombocytopenia on hemorrhagic complications after endovascular therapy for acute large vessel occlusion: Sub-analysis of RESCUE-Japan registry 2

BACKGROUND

Endovascular treatment (EVT) for patients with large vessel occlusion (LVO) and concurrent thrombocytopenia raises concerns about hemorrhagic complications. We examined the association between thrombocytopenia and clinical outcomes after EVT.

METHODS

This is a sub-analysis of the RESCUE-Japan Registry 2, a nationwide registry that enrolled 2420 consecutive acute LVO patients. We evaluated the clinical outcomes in patients who underwent EVT according to their platelet count on admission (Moderate/Severe, < 100 × 10⁹ /L; Mild, 100 to ≤150 × 10⁹/L; Normal, ≥ 150 × 10⁹/L). The outcomes included any and symptomatic intracranial hemorrhage (ICH) after EVT, and modified Rankin Scale (mRS) at 90 days.

RESULTS

Of 1268 patients who underwent EVT, the Moderate/Severe and Mild groups consisted of 41 (3.2%), and 193 (15.2%) patients. Any ICH occurred in 37%, 35%, and 24% of Moderate/Severe, Mild, and Normal group patients, respectively, and the adjusted ORs (95% CIs) were 1.50 (0.71-3.18) for Moderate/Severe and 1.87 (1.28-2.73) for Mild, compared to the Normal group (p for trend = 0.004). Symptomatic ICH increased with the severity of thrombocytopenia (9.8% vs 3.6% vs 2.1%), and adjusted ORs were 4.43 (1.16-17.0) in Moderate/Severe and 1.85 (0.71-4.86) in Mild (p for trend = 0.10). Mortality was significantly associated with the severity of thrombocytopenia (p for trend = 0.005), and adjusted ORs were 3.26 (1.29-8.26) in the Moderate/Severe and 2.76 (1.58-4.84) in the Mild groups.

CONCLUSIONS

Thrombocytopenia in LVO patients was not rare and associated with the incidence and manifestation of ICH after EVT.

Platelet count and clinical outcomes among ischemic stroke patients with endovascular thrombectomy in DIRECT-MT

OBJECTIVES

The prognostic role of baseline platelet count (PLT) in acute ischemic stroke patients with large vessel occlusion undergoing endovascular thrombectomy is unclear. Whether PLT modifies alteplase treatment effect on clinical outcome in those patients is also uncertain.

METHODS

We derived data from a multicenter randomized clinical trial (DIRECT-MT) comparing intravenous alteplase before endovascular treatment vs. endovascular treatment only. The 654 patients with available PLT data were included. Primary outcome was the ordinal modified Rankin Scale (mRS) score evaluated at 90 days. We also assessed various secondary and safety outcomes.

RESULTS

After adjusting for confounding factors, patients in the top tertile of PLT had a significantly lower risk of a worse shift in the distribution of mRS score (Odds Ratio: 0.671, 95% Confidence Interval: 0.473-0.953, p for trend=0.025), major disability and death (Odds Ratio: 0.617, 95% Confidence Interval: 0.393-0.97, p for trend=0.037) as well as death (Odds Ratio: 0.544, 95% Confidence Interval: 0.313-0.947, p for trend=0.031), respectively, compared with the bottom one. Among patients in the bottom tertile of PLT, combination therapy was associated with a better imaging outcome of eTICI score of 2b, 2c or 3 on final angiogram (Odds Ratio: 3.23, 95% Confidence Interval: 1.49-7.002) with a marginally significant interaction effect.

CONCLUSIONS

Participants with higher baseline PLT had a decreased risk of poor functional outcomes. Low baseline PLT modified alteplase treatment effect on the eTICI score on final angiogram. Combination therapy was beneficial for patients with low baseline PLT to have a better reperfusion status.

EHA Guidelines on Management of Antithrombotic Treatments in Thrombocytopenic Patients With Cancer

In cancer patients, thrombocytopenia can result from bone marrow infiltration or from anticancer medications and represents an important limitation for the use of antithrombotic treatments, including anticoagulant, antiplatelet, and fibrinolytic agents. These drugs are often required for prevention or treatment of cancer-associated thrombosis or for cardioembolic prevention in atrial fibrillation in an increasingly older cancer population. Data indicate that cancer remains an independent risk factor for thrombosis even in case of thrombocytopenia, since mild-to-moderate thrombocytopenia does not protect against arterial or venous thrombosis. In addition, cancer patients are at increased risk of antithrombotic drug-associated bleeding, further complicated by thrombocytopenia and acquired hemostatic defects. Furthermore, some anticancer treatments are associated with increased thrombotic risk and may generate interactions affecting the effectiveness or safety of antithrombotic drugs. In this complex scenario, the European Hematology Association in collaboration with the European Society of Cardiology has produced this scientific document to provide a clinical practice guideline to help clinicians in the management of patients with cancer and thrombocytopenia. The Guidelines focus on adult patients with active cancer and a clear indication for anticoagulation, single or dual antiplatelet therapy, their combination, or reperfusion therapy, who have concurrent thrombocytopenia because of either malignancy or anticancer medications. The level of evidence and the strength of the recommendations were discussed according to a Delphi procedure and graded according to the Oxford Centre for Evidence-Based Medicine.

Thrombocytopenia predicts mortality in Chinese hemodialysis patients- an analysis of the China DOPPS

BACKGROUND

Hemodialysis (HD) patients have a higher mortality rate compared with general population. Our previous study revealed that platelet counts might be a potential risk factor. The role of platelets in HD patients has rarely been studied. The aim of this study is to examine if there is an association of thrombocytopenia (TP) with elevated risk of all-cause mortality and cardiovascular (CV) death in Chinese HD patients.

METHODS

Data from a prospective cohort study, China Dialysis Outcomes and Practice Patterns Study (DOPPS) 5, were analyzed. Demographic data, comorbidities, platelet counts and other lab data, and death records which extracted from the medical record were analyzed. TP was defined as the platelet count below the lower normal limit (< 100*109/L). Associations between platelet counts and all-cause and CV mortality were evaluated using Cox regression models. Stepwise multivariate logistic regression was used to identify the independent associated factors, and subgroup analyses were also carried out.

RESULTS

Of 1369 patients, 11.2% (154) had TP at enrollment. The all-cause mortality rates were 26.0% vs. 13.3% (p < 0.001) in patients with and without TP. TP was associated with higher all-cause mortality after adjusted for covariates (HR:1.73,95%CI:1.11,2.71), but was not associated with CV death after fully adjusted (HR:1.71,95%CI:0.88,3.33). Multivariate logistic regression showed that urine output < 200 ml/day, cerebrovascular disease, hepatitis (B or C), and white blood cells were independent impact factors (P < 0.05). Subgroup analysis found that the effect of TP on all-cause mortality was more prominent in patients with diabetes or hypertension, who on dialysis thrice a week, with lower ALB (< 4 g/dl) or higher hemoglobin, and patients without congestive heart failure, cerebrovascular disease, or hepatitis (P < 0.05).

CONCLUSION

In Chinese HD patients, TP is associated with higher risk of all-cause mortality, but not cardiovascular mortality. Platelet counts may be a useful prognostic marker for clinical outcomes among HD patients, though additional study is needed.

Influence of Thrombocytopenia on the Outcome of Mechanical Thrombectomy in Patients with Acute Ischemic Stroke

OBJECTIVES

Mechanical thrombectomy (MT) has become leading treatment option for acute ischemic stroke (AIS) due to large vessels occlusion (LVO). Platelet counts may affect outcome in patients with AIS or transient ischemic attack. The aim of our study was to determine the influence of thrombocytopenia on the safety and efficacy of MT in patients with AIS due to anterior circulation LVO.

MATERIALS AND METHODS

This study included 127 consecutive adult patients with AIS due to anterior circulation LVO who underwent MT. The patients were divided into 2 groups based on initial platelet count: with thrombocytopenia (<150 × 10⁹/L) and without thrombocytopenia (≥150 × 10⁹/L). Primary safety outcome was symptomatic intracerebral haemorrhage (SICH), while secondary safety outcome was stroke-related mortality. Efficacy outcome was functional independence, defined as modified Rankin Scale (mRS) score 0-2. Follow- up time was 90 days.

RESULTS

Initial thrombocytopenia (<150 × 10⁹/L) was detected in 19 (15%) patients. Multivariable analysis showed that initial thrombocytopenia did not increase the risk of SICH and did not affect the short-term functional outcome (p = 0.587). However, initial thrombocytopenia increased the risk for stroke-related mortality (aOR 3.639, 95% CI 1.079-12.641, p = 0.037). The main cause of mortality in the group with thrombocytopenia was malignant cerebral infarction (44.4%).

CONCLUSIONS

Thrombocytopenia does not affect the efficacy and the risk of SICH in patients with AIS caused by anterior circulation LVO treated with MT. However, the risk of mortality is higher in patients with thrombocytopenia, mainly due to malignant cerebral infarction.

Fibrinogen Level Combined With Platelet Count for Predicting Hemorrhagic Transformation in Acute Ischemic Stroke Patients Treated With Mechanical Thrombectomy

A serious complication of acute ischemic stroke (AIS) after mechanical thrombectomy (MT) is hemorrhagic transformation (HT), which is potentially associated with clinical deterioration. This study examined predictors of HT following MT in AIS patients. Patients with AIS due to large artery occlusion in the anterior circulation, treated with MT and successfully recanalized (modified Thrombolysis in Cerebral Infarction score 2b/3), were studied retrospectively. HT was evaluated by computed tomography (CT) 24 h after MT and was diagnosed and classified into parenchymal hematoma (PH) and hemorrhagic infarction (HI). Multivariate logistic regression models were used to determine the risk factors for HT. Receiver operating characteristic (ROC) curve analysis was performed to determine the predictive utility of risk factors for HT. We enrolled 135 patients: 49 in the HT group and 86 in the non-HT group. The two groups differed significantly in baseline fibrinogen levels (p = 0.003) and platelet counts (p = 0.006). Multivariate logistic regression analyses showed that lower fibrinogen levels [odds ratio (OR), 0.41; 95% CI, 0.23–0.72; p = 0.002] and platelet counts (OR, 0.58; 95% CI, 0.33–0.99; p = 0.048) were independently associated with a higher risk of HT. Together, the binary variates fibrinogen and platelets well-predicted HT (area under the curve, 0.703; specificity, 77.9%; sensitivity, 55.1%). The combination of fibrinogen <2.165 g/L and platelets <171.5 × 10⁹/L was the strongest predictor of HT (OR, 23.17; 95% CI, 5.75–126.80; p < 0.0001). Our study suggests that lower baseline fibrinogen levels and platelet counts may be risk factors for HT in AIS patients following MT and reperfusion. Specifically, the combination of fibrinogen level and platelet count may predict the risk of HT after MT in these patients.

Thrombectomy in special populations: report of the Society of NeuroInterventional Surgery Standards and Guidelines Committee

BACKGROUND

The purpose of this guideline is to summarize the data available for performing mechanical thrombectomy (MT) for emergent large vessel occlusion (ELVO) stroke in special populations not typically included in large randomized controlled clinical trials, including children, the elderly, pregnant women, patients who have recently undergone surgery, and patients with thrombocytopenia, collagen vascular disorders, and endocarditis.

METHODS

We performed a literature review for studies examining the indications, efficacy, and outcomes for patients undergoing MT for ischemic stroke aged <18 years and >80 years, pregnant patients, patients who have recently undergone surgery, and those with thrombocytopenia, collagen vascular diseases, or endocarditis. We graded the quality of the evidence.

RESULTS

MT can be effective for the treatment of ELVO in ischemic stroke for patients over age 80 years and under age 18 years, thrombocytopenic patients, pregnant patients, and patients with endocarditis. While outcomes are worse compared to younger patients and those with normal platelet counts (respectively), there is still a benefit in the elderly (in both mRS and mortality). Data are very limited for patients with collagen vascular diseases; although diagnostic cerebral angiography carries increased risks, MT may be appropriate in carefully selected patients in whom untreated ELVO would likely result in disabling or fatal outcome.

Pre-procedural predictive factors of symptomatic intracranial hemorrhage after thrombectomy in stroke

OBJECTIVE

Symptomatic intracerebral hemorrhage (sICH) is a common complication of acute ischemic stroke (AIS) associated with limited treatments and poor outcomes. We aimed to identify predictive factors of sICH in patients with AIS following mechanical thrombectomy (MT) in a real-world setting.

METHODS

Patients with large vessel occlusion of the anterior circulation treated with MT were consecutively included in a prospective monocentric cohort. Clinical, biological, and radiological parameters were collected to identify pre-procedural predictors for sICH.

RESULTS

637 patients were included in our study. Magnetic resonance imaging was performed on most patients (86.7%). sICH occurred in 55 patients (8.6%). 428 patients (67.2%) were treated with intravenous thrombolysis. After multivariate analysis, prior use of antiplatelet therapies (odd ratio (OR) 1.84, 95% confidence interval (CI) 1.01-3.32), high C-reactive protein (OR per standard deviation (SD) increase 1.28, 95% 1.01-1.63), elevated mean arterial blood pressure (OR per 10 mmHg increase 1.22, 95% CI 1.03-1.44), hyperglycemia (OR per one SD-log increase 1.38, 95% CI 1.02-1.87), and low ASPECTS (OR per 1-point decrease 1.42, 95% CI 1.12-1.80) were found to be independent predictive factors of sICH. The pre-procedural predictors did not change when the absence of successful recanalization was considered as a covariate. Patients with strokes of unknown onset time were not especially vulnerable for sICH.

CONCLUSION

sICH after MT was associated with several pre-procedural risk factors: prior use of antiplatelet therapies, high C-reactive protein and hyperglycemia at baseline, elevated mean arterial blood pressure, and low ASPECTS.

Direct thrombectomy for stroke in the presence of absolute exclusion criteria for thrombolysis

BACKGROUND

Intravenous thrombolysis (IVT)-ineligible patients undergoing direct thrombectomy tended to have poorer functional outcome as compared with IVT-eligible patients undergoing bridging therapy. We aimed to assess radiological and functional outcomes in large vessel occlusion-related stroke patients receiving direct thrombectomy in the presence of absolute exclusion criteria for IVT vs relative exclusion criteria for IVT and vs non-exclusion criteria for IVT.

METHODS

A cohort study on prospectively collected data from 2282 patients enrolled in the Italian Registry of Endovascular Treatment in Acute Stroke cohort for treatment with direct thrombectomy (n = 486, absolute exclusion criteria for IVT alone; n = 384, absolute in combination with relative exclusion criteria for IVT; n = 777, relative exclusion criteria for IVT alone; n = 635, non-exclusion criteria for IVT).

RESULTS

After adjustment for unbalanced variables (model 1), ORs for 3-month death was higher in the presence of absolute exclusion criteria for IVT alone (vs relative exclusion criteria for IVT alone) (1.595, 95% CI 1.042-2.440) and in the presence of absolute exclusion criteria for IVT alone (vs non-exclusion criteria for IVT) (1.235, 95% CI 1.014-1.504). After adjustment for predefined variables (model 2: age, sex, pre-stroke mRS ≤ 1, NIHSS, occlusion in the anterior circulation, onset-to-groin time, and procedure time), ORs for 3-month death was higher in the presence of absolute exclusion criteria for IVT alone (vs relative exclusion criteria for IVT alone) (1.235, 95% CI 1.014-1.504) and in the presence of absolute exclusion criteria for IVT alone (vs non-exclusion criteria for IVT) (1.246, 95% CI 1.039-1.495). No significant difference was found between the groups as regards any type of intracerebral hemorrhage and parenchymal hematoma within 24 h, successful and complete recanalization after procedure, and modified Rankin Scale score 0-2 at 3 months. After adjustment for predefined variables of model 2, ORs for death were higher in the presence of recent administration of IV heparin (OR: 2.077), platelet count < 100,000/mm³ (OR: 4.798), bacterial endocarditis (OR: 15.069), neoplasm with increased hemorrhagic risk (OR: 6.046), and severe liver disease (OR: 6.124).

CONCLUSIONS

Radiological outcomes were similar after direct thrombectomy in patients with absolute, relative, and non- exclusion criteria for IVT, while an increase of fatal outcome was observed in the presence of some absolute exclusion criterion for IVT.

Impact of brain volume and intracranial cerebrospinal fluid volume on the clinical outcome in endovascularly treated stroke patients

PURPOSE

Previously, brain volume (BV) and intracranial cerebrospinal fluid volume (CSFV) have been investigated regarding clinical outcomes of subgroups of ischemic stroke patients. This study aimed to examine if the preexisting, preischemic BV and CSFV have an impact on good functional outcome and mortality in acute ischemic stroke (AIS) patients treated with mechanical thrombectomy (MT).

METHODS

Preischemic BV, CSFV, and CSFV/Total intracranial volume (TICV)-ratio were calculated with a fully automated segmentation platform. Univariate and multivariate analyses were used to study associations.

RESULTS

In this retrospective study 107 subsequent AIS patients of a prospective database were included. The segmentation results of the fully automated algorithm based on non-contrast computerized tomography scans (NCCT) correlated significantly with the segmentation results obtained from 3D T1 weighted magnetic resonance images (P < 0.001). In the univariate analysis a preexisting BV (P < 0.001), preexisting CSFV (P = 0.009), and the ratio CSFV/total intracranial volume (P < 0.001) each significantly correlated with good functional outcome and mortality. However, in the multivariate regression analysis, also correcting for patient age, none of these volumes remained to correlate with these outcome parameters.

CONCLUSION

In summary, an association of BV, CSFV, and the CSFV/TICV-ratio with good functional outcome and mortality in AIS treated with MT could not be established. A fully automated segmentation algorithm based on NCCT was successfully developed in-house for calculating the volumes of interest.

The effects of changes in platelet-to-neutrophil ratios 24 hours after intravenous thrombolysis on prognosis in acute ischemic stroke patients

OBJECTIVE

To investigate the prognostic value of Platelet-to-Neutrophil ratio on admission (PNR on admission) and 24 h after intravenous thrombolysis (24 h PNR) in acute ischemic stroke patients (AIS) patients.

PATIENTS AND METHODS

One hundred fifty-one ischemic stroke patients receiving intravenous thrombolysis were retrospectively recruited in this study. Complete blood count evaluations for PNR were conducted on admission and 24 h after the treatment of thrombolysis. The poor outcome at 3months was defined as the modified Rankin Scale of 3-6.

RESULTS

In multivariate logistic regression, PNR on admission (odds ratio [OR] = 0.967, 95 % confidence interval [CI] = 0.939-0.996; P = 0.028), and 24 h PNR(OR = 0.933, 95 %CI = 0.895-0.972; P = 0.004) were all independent indicators for the 3-month poor prognosis in ischemic stroke patients receiving intravenous thrombolysis. The area under the curve of PNR on admission to predict poor functional outcomes at 3 months was 0.645 (95 %CI = 0.558-0.732; P < 0.001), and the best predictive PNR on admission value was 41.35. After the treatment of thrombolysis, the area under the curve of 24 h PNR to predict poor functional outcomes at 3 months was 0.796 (95 %CI = 0.722-0.858; P < 0.001), and the best predictive 24 h PNR value was 31.03.

CONCLUSIONS

Both the PNR on admission and 24 h PNR were independently associated with poor functional outcomes. Compared with the PNR on admission, 24 h PNR may serve as a more reliable marker for a poor prognosis in ischemic stroke patients receiving intravenous thrombolysis.

Thrombocytopenia and Mortality Risk in Patients With Atrial Fibrillation: An Analysis From the START Registry

Background

Thrombocytopenia is associated with increased mortality in the general population, but few data exist in patients with atrial fibrillation (AF) taking oral anticoagulants. We investigated factor determinants of thrombocytopenia in a large cohort of patients affected by AF and its association with total mortality.

Methods and Results

Multicenter prospective cohort study, including 5215 patients with AF from the START (Survey on Anticoagulated Patients Register) registry, 3877 (74.3%) and 1338 (25.7%) on vitamin K or non–vitamin K antagonist oral anticoagulants, respectively. Thrombocytopenia was defined by a platelet count <150×10⁹/L. Determinants of thrombocytopenia were investigated, and all‐cause mortality was the primary survival end point of the study. Thrombocytopenia was present in 592 patients (11.4%). At multivariable logistic regression analysis, chronic kidney disease (odds ratio [OR], 1.257; P=0.030), active cancer (OR, 2.065; P=0.001), liver cirrhosis (OR, 7.635; P<0.001), and the use of diuretics (OR, 1.234; P=0.046) were positively associated with thrombocytopenia, whereas female sex (OR, 0.387; P<0.001) and the use of calcium channel blockers (OR, 0.787; P=0.032) were negatively associated. During a median follow‐up of 19.2 months (9942 patient‐years), 391 deaths occurred (rate, 3.93%/year). Mortality rate increased from 3.8%/year to 9.9%/year in patients with normal platelet count and in those with moderate‐severe thrombocytopenia, respectively (log‐rank test, P=0.009). The association between moderate‐severe thrombocytopenia and mortality persisted after adjustment for CHA₂DS₂VASc score (hazard ratio, 2.431; 95% CI, 1.254–4.713; P=0.009), but not in the fully adjusted multivariable Cox regression analysis model.

Conclusions

Thrombocytopenia is common in patients with AF. Despite an increased incidence of mortality, thrombocytopenia was not associated with mortality at multivariable analysis. Thrombocytopenia may reflect the presence of comorbidities associated with poor survival in AF.