Clopidogrel-associated autoimmune thrombocytopenic purpura

Effect of Preprocedural Thrombocytopenia on Prognosis After Percutaneous Coronary Intervention

OBJECTIVE

To assess early and late outcomes, including bleeding, in patients with thrombocytopenia undergoing percutaneous coronary intervention (PCI).

PATIENTS AND METHODS

We performed a retrospective single-center study of patients with preprocedural thrombocytopenia (platelet count ≤100,000/μL; n=204) undergoing PCI between 2003 and 2015. Inhospital and late outcomes were compared with those of a matched control group without thrombocytopenia (n=1281).

RESULTS

The most common causes of thrombocytopenia were liver disease, immune-mediated disease, and hematologic malignant neoplasms. Inhospital bleeding events after PCI were similar in patients with thrombocytopenia and matched controls (24 of 146 [16.4%] vs 179 of 1281 [14.0%]; P=.40) and were largely classified as minor using the Bleeding Academic Research Consortium (BARC) classification (89% BARC 1 or 2). There was no significant difference in inhospital death (4 of 146 [2.7%] vs 71 of 1281 [2.0%]; P=.56), but patients with thrombocytopenia had higher rates of platelet and red blood cell transfusion (18 of 146 [12.3%] vs 93 of 1281 [7.2%]; P=.05). During long-term follow-up, Kaplan-Meier estimated rates of bleeding events (BARC ≥2) were higher for thrombocytopenia (at 5 years, 7.9% vs 3.6%; P=.03). Patients with thrombocytopenia had a similar risk of long-term cardiac mortality, but significantly higher rates of noncardiac mortality (at 5 years, 28% vs 21%; P=.02).

CONCLUSION

This study suggests that short-term outcomes after PCI in patients with thrombocytopenia were favorable. On long-term follow-up, thrombocytopenia was associated with a higher risk of long-term noncardiac mortality and bleeding.

SCAI Expert consensus statement: Evaluation, management, and special considerations of cardio-oncology patients in the cardiac catheterization laboratory (endorsed by the cardiological society of india, and sociedad Latino Americana de Cardiologıa intervencionista)

In the United States alone, there are currently approximately 14.5 million cancer survivors, and this number is expected to increase to 20 million by 2020. Cancer therapies can cause significant injury to the vasculature, resulting in angina, acute coronary syndromes (ACS), stroke, critical limb ischemia, arrhythmias, and heart failure, independently from the direct myocardial or pericardial damage from the malignancy itself. Consequently, the need for invasive evaluation and management in the cardiac catheterization laboratory (CCL) for such patients has been increasing. In recognition of the need for a document on special considerations for cancer patients in the CCL, the Society for Cardiovascular Angiography and Interventions (SCAI) commissioned a consensus group to provide recommendations based on the published medical literature and on the expertise of operators with accumulated experience in the cardiac catheterization of cancer patients.

The change in platelet count in patients with acute coronary syndrome 6 months after coronary stent implantation

After coronary stent implantation, patients with acute coronary syndrome commonly take clopidogrel, and few patients develop severe thrombocytopenia related to clopidogrel. However, we found in our clinical practice that platelet counts of most patients decrease slightly after taking clopidogrel for 6 months. To address this discrepancy, we studied the change in platelet count after coronary stent implantation in patients with acute coronary syndrome. Ninety-five patients were selected for this study, and their prestent platelet counts were compared with those 6 months after stent implantation. All patients had low/intermediate-risk non-ST segment elevation myocardial infarction/unstable angina and underwent delayed coronary interventional treatment. No patient suffered from thrombocytopenia (<100 × 10⁹/l) during the 6-month observation period. Six months after stent implantation, platelet counts significantly decreased in the majority of patients (73/95, 76.9%) and increased only in the minority of patients (22/95, 23.1%). A multivariate analysis showed that the change in platelet count was positively correlated with the change in leukocyte and fibrinogen value, and negatively correlated with number of stents. The platelet count decreased in the majority of patients after stent implantation, which may be caused by the removal of stress factors or stent-related platelet consumption. Clopidogrel may partly prevent stent-related platelet consumption.

Impact of baseline thrombocytopenia on the early and late outcomes after ST-elevation myocardial infarction treated with primary angioplasty: analysis from the Harmonizing Outcomes with Revascularization and Stents in Acute Myocardial Infarction (HORIZONS-AMI) trial

BACKGROUND

Thrombocytopenia (TP) is a common abnormality in patients presenting with acute coronary syndrome. Whether baseline TP has any influence on the outcome of patients treated with primary angioplasty for acute myocardial infarction is unknown.

METHODS

We sought to detect the impact of baseline TP on the early and late outcomes of patients with ST-elevation myocardial infarction in the HORIZONS-AMI trial that included a protocol of immediate angiography and primary percutaneous coronary intervention.

RESULTS

Baseline TP was found in 4.2% of patients and was associated with a higher incidence of cardiovascular mortality, major bleeding, and major cardiovascular events at short- and long-term follow-up. The 30-day rates of death, major bleeding, major cardiac events, and major cardiac events plus major bleeding were 6.2%, 11.9%, 9.6%, and 18.5% in the TP group, respectively, compared with 2.1%, 7%, 5.2%, and 10.8% in those without TP (P < .05 for all). Similarly, event rates at 2 years were 11.3%, 12.7%, 24.7%, and 30.8% compared with 5.1%, 7.9%, 18.5%, and 23.3% (P < .05). By multivariate analysis, baseline TP was an independent predictor of 30-day net adverse clinical events but not of any 2-year events.

CONCLUSIONS

We found that baseline TP in patients with ST-elevation myocardial infarction undergoing routine angiography and primary percutaneous coronary intervention is strongly associated with early adverse events and is a maker of late events, related to both ischemia and bleeding.

Profound thrombocytopenia induced by clopidogrel with a prior history of long-term safe administration

Clopidogrel has shown an excellent safety, tolerability and efficacy ever since its marketing. However, here we report a rare case with profound thrombocytopenia following clopidogrel administration previously safely exposed to this same drug. This reminds us that thrombocytopenia might be induced by clopidogrel even with a prior, safe history of long-term administration.

Thrombocytopenia at baseline is a predictor of inhospital mortality in patients undergoing percutaneous coronary intervention

BACKGROUND

Thrombocytopenia (TP) is a common baseline abnormality in patients undergoing percutaneous coronary intervention (PCI). Whether TP has any influence on the outcome of PCI patients is unknown. Our aim was to determine if TP at baseline impacts on inhospital mortality in patients undergoing PCI at our institution.

METHODS

From April 2000 until October 2005, 11,021 PCI procedures were performed at the University Health Network in Toronto, Canada. Baseline platelet count was recorded in 10,821 (98.2%) cases. Patients with platelets <150 x 10(9)/L were assigned to the TP group (n = 639), and those with > or =150 x 10(9)/L to the normal platelet group (n = 10,182). Clinical, angiographic, procedural, and inhospital outcome data were collected prospectively. Multivariable analysis was performed using logistic regression.

RESULTS

In-hospital death rate was higher in the TP group (1.9% vs 0.6%, P < .001) due to an increased mortality in TP patients undergoing urgent (3.55% vs 1.15%, P < .001) but not elective (0% vs 0.04%, P = 1.0) PCI. Major bleeding (1.7% vs 0.8%, P < .05) and gastrointestinal bleeding (1.1% vs 0.5%, P < .05) complications were greater in the TP group. Multivariate analysis demonstrated that baseline TP was an independent predictor of inhospital mortality (odds ratio 2.07 [1.1-4.1], P = .035).

CONCLUSIONS

Baseline TP is an independent predictor of inhospital mortality in patients undergoing PCI for urgent indications. Thrombocytopenia should be considered an important addition to PCI risk prediction models to improve their precision and clinical applicability.