Time course of the antiplatelet effect after switching to clopidogrel from initial prasugrel therapy in patients with acute coronary syndrome.

Prasugrel is often replaced with clopidogrel after a certain period of time following coronary stenting. However, the time course of platelet aggregation during this replacement is unknown. We performed a prospective, single-arm study to monitor platelet reactivity before and after the replacement. Forty-five patients (mean age 62.6 ± 13 years, 40 male) who received coronary stenting for acute coronary syndrome were initially treated with the loading dose (20 mg) of prasugrel followed by the maintenance dose (3.75 mg/day) for 7 days, then switched to 75 mg/day of clopidogrel. The P2Y12 reaction unit (PRU) level was measured at baseline and selected time points. Prasugrel effectively suppressed PRU from 248 ± 59 at baseline to 145 ± 65 on day 1 (P < 0.001). The PRU value on the final day of prasugrel treatment (day 7) was 156 ± 68 (P < 0.001 vs. baseline). After switching to clopidogrel, PRU was consistently suppressed [146 ± 60, 139 ± 54, and 135 ± 60 on days 9, 11, and 13, respectively (P < 0.001, each point vs. baseline)]. Switching from the initial prasugrel therapy to clopidogrel using the maintenance dose does not cause a drug efficacy gap and stays effective for preventing stent thrombosis.

Impact of ß-blocker selectivity on long-term outcomes in congestive heart failure patients with chronic obstructive pulmonary disease.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is present in approximately one-third of all congestive heart failure (CHF) patients, and is a key cause of underprescription and underdosing of ß-blockers, largely owing to concerns about precipitating respiratory deterioration. For these reasons, the aim of this study was to evaluate the impact of ß-blockers on the long-term outcomes in CHF patients with COPD. In addition, we compared the effects of two different ß-blockers, carvedilol and bisoprolol. METHODS: The study was a retrospective, non-randomized, single center trial. Acute decompensated HF patients with COPD were classified according to the oral drug used at discharge into ß-blocker (n=86; carvedilol [n=52] or bisoprolol [n=34]) and non-ß-blocker groups (n=46). The primary endpoint was all-cause mortality between the ß-blocker and non-ß-blocker groups during a mean clinical follow-up of 33.9 months. The secondary endpoints were the differences in all-cause mortality and the hospitalization rates for CHF and/or COPD exacerbation between patients receiving carvedilol and bisoprolol. RESULTS: The mortality rate was higher in patients without ß-blockers compared with those taking ß-blockers (log-rank P=0.039), and univariate analyses revealed that the use of ß-blockers was the only factor significantly correlated with the mortality rate (hazard ratio: 0.41; 95% confidence interval: 0.17-0.99; P=0.047). Moreover, the rate of CHF and/or COPD exacerbation was higher in patients treated with carvedilol compared with bisoprolol (log-rank P=0.033). In the multivariate analysis, only a past history of COPD exacerbation significantly increased the risk of re-hospitalization due to CHF and/or COPD exacerbation (adjusted hazard ratio: 3.11; 95% confidence interval: 1.47-6.61; P=0.003). CONCLUSION: These findings support the recommendations to use ß-blockers in HF patients with COPD. Importantly, bisoprolol reduced the incidence of CHF and/or COPD exacerbation compared with carvedilol.