Ticagrelor-associated thrombotic thrombocytopenic purpura

Progress in the clinical effects and adverse reactions of ticagrelor

BACKGROUND

Ticagrelor is a novel receptor antagonist that selectively binds to the P2Y12 receptor, thereby inhibiting adenosine diphosphate (ADP)-mediated platelet aggregation. Compared to clopidogrel, ticagrelor has the advantages of a fast onset, potent effects, and a reversible platelet inhibition function, which make this drug clinically suitable for treating acute coronary syndrome (ACS), especially acute ST-segment elevation myocardial infarction (STEMI).

OBJECTIVE

This review was performed to determine the basic characteristics, clinical effects, and adverse reactions of ticagrelor.

METHODS

Relevant trials and reports were obtained from the MEDLINE, Embase, and Cochrane Library databases.

RESULTS

Ticagrelor is rapidly absorbed by the body after oral administration, exhibits inherent activity without requiring metabolic activation, and binds reversibly to the P2Y12 receptor. Ticagrelor has been recommended in ACS treatment guidelines worldwide due to its advantageous pharmacological properties and significant clinical benefits. Ticagrelor inhibits platelet aggregation, inhibits inflammatory response, enhances adenosine function, and has cardioprotective effects. However, ticagrelor also causes adverse reactions such as bleeding tendency, dyspnea, ventricular pause, gout, kidney damage, and thrombotic thrombocytopenic purpura in clinical treatment. Therefore, it is necessary to pay attention to risk assessments when using ticagrelor.

CONCLUSION

Ticagrelor is a promising drug for the effective treatment of ACS. When using ticagrelor, individualized treatment should be provided based on the specific conditions of the patients to avoid serious adverse events.

Can platelet count be controlled with ticagrelor in patients with essential thrombocythaemia? A case series

Background

Essential thrombocythaemia (ET) is defined as a myeloproliferative neoplasm with a tendency to haemorrhage and thrombosis. Acute coronary thrombosis can be observed in 1 out of 10 patients. The management of ET patients with acute coronary syndrome (ACS) is a complex clinical condition that requires close follow-up.

Case summary

Case-1: a 52-year-old female patient with a diagnosis of ET with Janus kinase (JAK)--2 mutation, despite using cytoreductive agents, platelet counts could not be controlled. Platelet counts started to follow a normal course with the ticagrelor treatment given after ACS. Case-2: a 49-year-old female patient who was given ticagrelor treatment after ACS was found to have JAK-2+ ET. The patient whose platelet count returned to normal after ticagrelor treatment was using a cytoreductive agent before the index event. Case-3: a 54-year-old female patient with ET without any genetic mutation. In the patient whose platelet count did not decrease despite ticagrelor treatment and cytoreductive agents given after ACS, platelet counts returned to normal with interferon therapy.

Discussion

Platelet counts returned to the normal range with ticagrelor treatment given after ACS in patients with JAK+ ET. Monitoring platelet reduction in JAK+ patients with P2Y12 inhibition is thought to be important for new treatment options.

A case report of absolute thrombocytopenia with ticagrelor

BACKGROUND

We report a rare case of absolute thrombocytopenia with ticagrelor after 6 h of single loading dose of ticagrelor.

CASE SUMMARY

A 68-year-old male with ischaemic cardiomyopathy, hypertension, and dyslipidaemia presented with chest pain. He was found to be in new-onset atrial flutter and ruled in for a non-ST-segment elevation myocardial infarction. An echocardiogram showed decreased left ventricular ejection fraction, estimated at 15-20% and serum troponin peaked at 0.2 ng/dL, baseline platelet count was 203 × 103/µL. He underwent a drug-eluting stent placement to the right coronary artery with excellent angiographic results. He received 3000 units of unfractionated heparin and 180 mg of ticagrelor during the procedure. About 6 h after the procedure, he had coffee ground emesis. A complete blood count revealed a platelet count of 2 × 103 and 0 × 103/µL on repeat testing. Peripheral smear did not show any evidence of platelet clumping and schistocytes, serum haptoglobin and lactate dehydrogenase were normal. Ticagrelor and heparin were discontinued, while the aspirin was continued. Five units of platelet were transfused. The platelet count improved to 200 × 103/µL. Since his CHADS2VASC score was 3, he was discharged on apixaban and clopidogrel in addition to other medication. No thrombocytopenia was seen on outpatient follow-up.

DISCUSSION

The common side effects of ticagrelor include bleeding, dyspnoea, gynaecomastia, and rarely thrombotic thrombocytopenic purpura. Although extremely rare, absolute or profound thrombocytopenia can occur with ticagrelor, hours after administration and should be considered when other potential causes of thrombocytopenia have been ruled out.

Ticagrelor-induced thrombotic thrombocytopenic purpura: A case report and review of the literature

RATIONALE

Ticagrelor, a new type of P2Y12 receptor antagonist, has been highly recommended to be used in acute coronary syndrome by the latest guideline, but its side effects are not well-known. We seek to illustrate a potential fatal condition, thrombotic thrombocytopenic purpura (TTP), caused by ticagrelor.

PATIENT CONCERNS

An 87-year-old man who had been prescribed with ticagrelor for 2 months after ST-elevation myocardial infarction (STEMI), presented with severe thrombocytopenia, anemia, renal and liver dysfunction, heart failure and fever.

DIAGNOSES

Peripheral blood smear showed schistocytosis, and a disintegrin and metalloproteinase with thrombospondin motifs 13 (ADAMTS13) activity is low, with normal initial coagulation tests, which were compatible with a diagnosis of TTP.

INTERVENTIONS

After cessation of ticagrelor and initiation of therapeutic plasma exchange, our patient recovered.

OUTCOMES

Re-administration of ticagrelor aggravated TTP and led the patient to death.

LESSONS

Clinicians should be aware of the possibility of ticagrelor-induced TTP in patients with a history of recent myocardial infarction; It is of crucial significance to discontinue and never reuse ticagrelor as long as it is suspected to be implicated in TTP.