Clopidogrel use in coronary heart disease and percutaneous coronary intervention.

Antiplatelet therapy has proven efficacy in the management of atherothrombosis. Clopidogrel, a thienopyridine, is a potent antiplatelet agent that achieves its antiplatelet effects by inhibiting the binding of adenosine 5' diphosphate to its platelet receptor. Large clinical trials have demonstrated a role for clopidogrel in the management of symptomatic atherosclerosis, acute coronary syndromes, and patients undergoing percutaneous coronary intervention. In this review, we discuss the pharmacology of clopidogrel including the mechanism of action, review the major clinical trials that have defined the current role of clopidogrel in coronary heart disease and percutaneous coronary intervention, and, finally, examine the concept of clopidogrel resistance and its potential clinical implications.

Abnormal PFA-100 closure time is associated with increased platelet aggregation in patients presenting with chest pain.

BACKGROUND: Antiplatelet therapy has been proven to be effective for both primary and secondary prevention of myocardial infarction, stroke, and cardiovascular death. However, a significant proportion of patients treated with aspirin experience ischemic events. A number of prospective studies have demonstrated that decreased responsiveness to antiplatelet therapy as measured by various methods, is strongly associated with an increase in clinical events. Our objective was to characterize platelet function in patients presenting with chest pain using a point-of-care assay, PFA-100 and correlating results to traditional platelet aggregometry to determine if patients with aspirin non-responsiveness have increased clinical sequelae. METHODS: Platelet function was assessed using PFA-100, flow cytometry, and optical aggregometry in 94 patients presenting to the emergency department with chest pain. All patients were on aspirin 81-325 mg daily. Clinical events occurring during the index hospitalization were documented. RESULTS: Forty-seven patients (50%) were defined as aspirin non-responders by PFA-100 (collagen-epinephrine closure time

Resuscitation and recovery from acute right ventricular failure using a percutaneous right ventricular assist device.

A number of techniques have been proposed for circulatory support in patients with severe right heart failure. We report on a patient with right ventricular (RV) infarction complicated by cardiogenic shock, who was resuscitated by the novel use of a percutaneous right ventricular assist device. The moribund patient had striking hemodynamic and clinical improvement after placement of a right atrial to pulmonary artery assist circuit. RV decompression for 3 days was accompanied by recovery of contractile function, and the patient was successfully weaned from the device. Future trials are needed to assess the effectiveness of the percutaneous ventricular assist device in patients with RV failure.