Faculty Bibliography

Summary. Background: The CYP2C19 genotype is a predictor of adverse cardiovascular events in acute coronary syndrome (ACS) patients undergoing percutaneous coronary intervention (PCI) treated with clopidogrel. Objectives: We aimed to evaluate the cost-effectiveness of a CYP2C19*2 genotype-guided strategy of antiplatelet therapy in ACS patients undergoing PCI, compared with two 'no testing' strategies (empiric clopidogrel or prasugrel). Methods: We developed a Markov model to compare three strategies. The model captured adverse cardiovascular events and antiplatelet-related complications. Costs were expressed in 2010 US dollars and estimated using diagnosis-related group codes and Medicare reimbursement rates. The net wholesale price for prasugrel was estimated as $5.45 per day. A generic estimate for clopidogrel of $1.00 per day was used and genetic testing was assumed to cost $500. Results: Base case analyses demonstrated little difference between treatment strategies. The genetic testing-guided strategy yielded the most QALYs and was the least costly. Over 15 months, total costs were $18 lower with a gain of 0.004 QALY in the genotype-guided strategy compared with empiric clopidogrel, and $899 lower with a gain of 0.0005 QALY compared with empiric prasugrel. The strongest predictor of the preferred strategy was the relative risk of thrombotic events in carriers compared with wild-type individuals treated with clopidogrel. Above a 47% increased risk, a genotype-guided strategy was the dominant strategy. Above a clopidogrel cost of $3.96 per day, genetic testing was no longer dominant but remained cost-effective. Conclusions: Among ACS patients undergoing PCI, a genotype-guided strategy yields similar outcomes to empiric approaches to treatment, but is marginally less costly and more effective.

BACKGROUND: The incidence and predictors of heart failure (HF) after myocardial infarction (MI) with modern post-MI treatment have not been well characterized. METHODS AND RESULTS: A total of 2,201 stable patients with persistent infarct-related artery occlusion >24 hours after MI with left ventricular ejection fraction <50% and/or proximal coronary artery occlusion were randomized to percutaneous intervention plus optimal medical therapy (PCI) or optimal medical therapy (MED) alone. Centrally adjudicated HF hospitalizations for New York Heart Association (NYHA) III/IV HF and mortality were determined in patients with and without baseline HF, defined as a history of HF, Killip Class >I at index MI, rales, S3 gallop, NYHA II at randomization, or NYHA >I before index MI. Long-term follow-up data were used to determine 7-year life-table estimated event rates and hazard ratios. There were 150 adjudicated HF hospitalizations during a mean follow-up of 6 years with no difference between the randomized groups (7.4% PCI vs. 7.5% MED, P = .97). Adjudicated HF hospitalization was associated with subsequent death (44.0% vs. 13.1%, HR 3.31, 99% CI 2.21-4.92, P < .001). Baseline HF (present in 32% of patients) increased the risk of adjudicated HF hospitalization (13.6% vs. 4.7%, HR 3.43, 99% CI 2.23-5.26, P < .001) and death (24.7% vs. 10.8%, HR 2.31, 99% CI 1.71-3.10, P < .001). CONCLUSIONS: In the overall Occluded Artery Trial (OAT) population, adjudicated HF hospitalizations occurred in 7.5% of subjects and were associated with increased risk of subsequent death. Baseline or prior HF was common in the OAT population and was associated with increased risk of hospitalization and death.

BACKGROUND: The effect of intensified platelet inhibition for patients with unstable angina or myocardial infarction without ST-segment elevation who do not undergo revascularization has not been delineated. METHODS: In this double-blind, randomized trial, in a primary analysis involving 7243 patients under the age of 75 years receiving aspirin, we evaluated up to 30 months of treatment with prasugrel (10 mg daily) versus clopidogrel (75 mg daily). In a secondary analysis involving 2083 patients 75 years of age or older, we evaluated 5 mg of prasugrel versus 75 mg of clopidogrel. RESULTS: At a median follow-up of 17 months, the primary end point of death from cardiovascular causes, myocardial infarction, or stroke among patients under the age of 75 years occurred in 13.9% of the prasugrel group and 16.0% of the clopidogrel group (hazard ratio in the prasugrel group, 0.91; 95% confidence interval [CI], 0.79 to 1.05; P=0.21). Similar results were observed in the overall population. The prespecified analysis of multiple recurrent ischemic events (all components of the primary end point) suggested a lower risk for prasugrel among patients under the age of 75 years (hazard ratio, 0.85; 95% CI, 0.72 to 1.00; P=0.04). Rates of severe and intracranial bleeding were similar in the two groups in all age groups. There was no significant between-group difference in the frequency of nonhemorrhagic serious adverse events, except for a higher frequency of heart failure in the clopidogrel group. CONCLUSIONS: Among patients with unstable angina or myocardial infarction without ST-segment elevation, prasugrel did not significantly reduce the frequency of the primary end point, as compared with clopidogrel, and similar risks of bleeding were observed. (Funded by Eli Lilly and Daiichi Sankyo; TRILOGY ACS ClinicalTrials.gov number, NCT00699998.).

Renal dysfunction is an independent predictor of cardiovascular events and a negative prognostic indicator after myocardial infarction (MI). Randomized data comparing percutaneous coronary intervention to medical therapy in patients with MI with renal insufficiency are needed. The Occluded Artery Trial (OAT) compared optimal medical therapy alone to percutaneous coronary intervention with optimal medical therapy in 2,201 high-risk patients with occluded infarct arteries >24 hours after MI with serum creatinine levels 90 ml/min/1.73 m(2), 19.2% for eGFR 60 to 89 ml/min/1.73 m(2), and 34.9% for eGFR <60 ml/min/1.73 m(2); p <0.0001), death, and class IV HF, with no difference in rates of reinfarction. On multivariate analysis, eGFR was an independent predictor of death and HF. There was no effect of treatment assignment on the primary end point regardless of eGFR, and there was no significant interaction between eGFR and treatment assignment on any outcome. In conclusion, lower eGFR at enrollment was independently associated with death and HF in OAT participants. Despite this increased risk, the lack of benefit from percutaneous coronary intervention in the overall trial was also seen in patients with renal dysfunction and persistent occlusion of the infarct artery in the subacute phase after MI.