Antiplatelet drug resistance in patients with recurrent acute coronary syndrome undergoing conservative management.
OBJECTIVE
Recurrent ischemic events continue to occur despite combination anti-platelet therapy. Currently aspirin, clopidogrel and dual resistance are increasingly recognized entities. The relationship of such resistance to recurrent ischemic events is largely unknown. In this study, we tried to gain an insight into the role of antiplatelet drug resistance with recurrent Acute Coronary Syndrome (ACS).


METHODS
The antiplatelet effect of aspirin and clopidogrel was studied in 40 recurrent ACS patients and 170 patients with first episode of ACS, after > or = 7 days of dual antiplatelet therapy. Platelet aggregation study was done with optical aggregometer. Resistance to aspirin and clopidogrel was defined as > or = 50% aggregation with collagen and ADP respectively.


RESULTS
Aspirin, clopidogrel and dual drug resistance were encountered respectively in 35%, 72.5% and 32.5% patients with recurrent ACS. The corresponding figures for the patients with first episode of ACS were 25.3%, 42.3% and 18.8% respectively. P values for the comparisons were 0.237 for aspirin, 0.0007 for clopidogrel and 0.084 for dual drugs. Patients with recurrent ACS were relatively younger and had a higher prevalence of conventional risk factors like hypertension, diabetes and elevated LDL.


CONCLUSIONS
Antiplatelet drug resistance is likely to play an important role in recurrent ACS alongside other conventional risk factors. Further research is required in this field to have a definitive conclusion.
Guha
Santanu
S
Department of Cardiology, Medical College, Kolkata, West Bengal, India. guhas55@hotmail.com
Mookerjee
Soura
S
Guha
Pradipta
P
Sardar
Partha
P
Deb
Suryyani
S
Roy
Puspita Das
PD
Karmakar
Rathindranath
R
Mani
Siddhartha
S
Hema
M B
MB
Pyne
Santasil
S
Chakraborti
Prantar
P
Deb
P K
PK
Lahiri
Prabir
P
Chaudhuri
Utpal
U
D054058:Acute Coronary Syndrome; D000328:Adult; D000077144:Clopidogrel; D004361:Drug Tolerance; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010975:Platelet Aggregation Inhibitors / Q000494:pharmacology*; D010979:Platelet Function Tests; D012008:Recurrence; D013988:Ticlopidine / Q000031:analogs & derivatives* / Q000494:pharmacology
D010975:Platelet Aggregation Inhibitors; D000077144:Clopidogrel; D013988:Ticlopidine