CardioNerds (Amit and Dan) join Dr. Omid Amidi (CardioNerds Academy Graduate) and Dr. Marwah Shahid from the UCLA Cardiology Fellowship program along with Dr. Evelyn Song (CardioNerds Academy House Faculty and Heart Failure Hospitalist at UCSF) to discuss a complex case focused on management of severe coronary artery disease in a patient with Glanzmann thrombasthenia. Dr. Rushi Parikh (Interventional cardiologist, UCLA) provides the ECPR for this episode. Audio editing by CardioNerds Academy Intern, student doctor Akiva Rosenzveig.
Glanzmann Thrombasthenia is a bleeding disorder due to impairment of platelet aggregation secondary to a mutation in the GPIIB/IIIA receptor. This case is focused on work up of stable coronary artery disease followed by a discussion on duration of dual antiplatelet therapy post percutaneous coronary intervention in a patient with Glanzmann thrombasthenia.
Episode Schematics & Teaching
1. Patients with Glanzmann thrombocytopenia (GT) may have a higher risk of bleeding, depending on their disease phenotype.
2. It is unclear whether the mechanism of GT protects patient against stent thrombosis in the setting of PCI. Additionally, there is little data on the use of antiplatelet agents in patients with GT.
3. Short-term DAPT may be a reasonably safe option for patients with GT undergoing PCI.
4. We report a successful case of percutaneous coronary intervention in a patient with GT with no complications at a 1 year follow up.
1. What is Glanzmann thrombasthenia?
GT is an inherited platelet disorder that is characterized by spontaneous bleeding with phenotypic variability ranging from minimal bruising to potentially fatal hemorrhaging. GT is caused by autosomal recessive inheritance of quantitative or qualitative deficiencies of functional αIIbβ3 integrin coded by ITGA2B or ITGB3 genes for αIIb and β3, respectively. As a result, platelets may be stimulated, but the platelet glycoprotein IIb/IIIa receptor is unable to bind fibrinogen to cross-link platelets, rending them potentially ineffective. In platelet aggregation studies, there is lack of response to collagen, epinephrine, arachidonic acid, and ADP stimulation. Thus, platelet aggregation is impaired.
2. What is known about PCI and antiplatelet therapy in the setting of Glanzmann thrombasthenia?
To the best of our knowledge, this is the first case report of percutaneous coronary intervention in the setting of GT. It is unclear if the mechanism of GT alone provides sufficient antiplatelet activity and whether antiplatelet therapy leads to significantly increased bleeding risk. The use of antiplatelet therapy is not well studied in the GT population. What we do know is that the mechanism of GT prevents platelet aggregation—the final step in platelet-related thrombosis—while oral antiplatelet therapy affects platelet activation, thus, in our patient we felt that short term DAPT was reasonable. It is important to note that in the event of an active bleed requiring platelet transfusion, donor platelets possess functional glycoprotein IIb/IIIa receptors and thus exponentially increase the risk of stent thrombosis. Therefore, unlike our case, if a patient is not maintained on chronic oral antiplatelet therapy, initiation of oral or intravenous antiplatelet therapy should be considered to prevent stent thrombosis at the time of platelet transfusion.
Like any other patient with a high bleeding risk, it is important to have clear indications to conduct a coronary angiogram in patients with GT. Shared decision making is vital in regard to the benefits and risk of an angiogram in relation to the patient’s presentation, symptoms and history. The same is true in regard to coronary revascularization in these patients. Besides functional stress testing, coronary CTA is a viable option to evaluate coronary anatomy to identify high risk anatomy in these patients.
- Truong Katie P., Zhang Jessica J., Shahid Marwah, et al. Management of high-grade coronary artery disease and concomitant glanzmann thrombasthenia. JACC: Case Reports. 2021;3(14):1625-1629.
- Lawton Jennifer S., Tamis-Holland Jacqueline E., et al. 2021 acc/aha/scai guideline for coronary artery revascularization. Journal of the American College of Cardiology. 2022;79(2):e21-e129.
- Gulati Martha, Levy Phillip D., et al. 2021 aha/acc/ase/chest/saem/scct/scmr guideline for the evaluation and diagnosis of chest pain. Journal of the American College of Cardiology. 2021;78(22):e187-e285.