Increased bodyweight and inadequate response to aspirin in individuals with coronary artery disease.

Recent reports have suggested that aspirin effect might be influenced by bodyweight, with decreased efficacy in heavier individuals. We investigated the influence of bodyweight on aspirin pharmacodynamics in two independent datasets of patients taking non-enteric coated aspirin 100 mg QD for coronary artery disease (CAD). In the first dataset, 368 patients had their platelet aggregation assessed using VerifyNow Aspirin and measured in Aspirin Reaction Units (ARU). In the second dataset, 70 patients had serum thromboxane B2 (TXB2) dosage assessed by an ELISA assay and measured in pg/mL. Platelet aggregation was independently associated with bodyweight, with 8.41 (95% CI 1.86-14.97; adjusted p-value = 0.012) increase in ARU for every 10 kg. Furthermore, the rate of non-response to aspirin (defined as ARU ≥ 550) was significantly associated with increased bodyweight (adjusted p-value = 0.007), with OR = 1.23 (95% CI 1.06-1.42) for every 10 kg. Similar results were found considering body mass index (in kg/m2), with 15.5 (95% CI 5.0 to 25.9; adjusted p-value = 0.004) increase in ARU for every 10 kg and non-response OR = 1.43 (95% CI 1.13 to 1.81, adjusted p-value = 0.003) for every 5 kg/m2. Moreover, serum TXB2 was higher in patients weighting more than 70 kg (222.6 ± 62.9 versus 194.9 ± 61.9 pg/mL; adjusted p-value = 0.018). In two different datasets of patients with CAD on non-enteric coated aspirin 100 mg QD, increased bodyweight was independently associated with impaired response to aspirin.

Long-term mortality after acute coronary syndromes among patients with normal, mildly reduced, or reduced ejection fraction.

AIMS: Left ventricular ejection fraction (LVEF) ≤ 40% is a well-established risk factor for mortality after acute coronary syndromes (ACS). However, the long-term prognostic impact of mildly reduced ejection fraction (EF) (LVEF 41-49%) after ACS remains less clear. METHODS AND RESULTS: This was a retrospective study enrolling patients admitted with ACS included in a single-centre databank. LVEF was assessed by echocardiography during index hospitalization. Patients were divided in the following categories according to LVEF: normal (LVEF ≥ 50%), mildly reduced (LVEF 41-49%), and reduced (LVEF ≤ 40%). The endpoint of interest was all-cause death after hospital discharge. A multivariable Cox model was used to adjust for confounders. A total of 3200 patients were included (1952 with normal EF, 375 with mildly reduced EF, and 873 with reduced EF). The estimated cumulative incidence rates of mortality at 10 years for patients with normal, mildly reduced, and reduced EF were 24.8%, 33.5%, and 41.3%, respectively. After adjustments, the presence of reduced EF was associated with higher mortality compared with normal EF [adjusted hazard ratio (HR) 1.64; 95% confidence interval (CI) 1.36-1.96; P < 0.001], as was mildly reduced EF compared with normal EF (adjusted HR 1.33; 95% CI 1.05-1.68; P = 0.019). The presence of reduced EF was not associated with a statistically significantly higher mortality compared with mildly reduced EF (adjusted HR 1.23; 95% CI 0.96-1.57; P = 0.095). CONCLUSIONS: In patients with ACS, mildly reduced EF measured in the acute phase was associated with higher long-term mortality compared with patients with normal EF. These data emphasize the importance of anti-remodelling therapies for ACS patients who have LVEF in the mildly reduced range.

Relation of High Lipoprotein (a) Concentrations to Platelet Reactivity in Individuals with and Without Coronary Artery Disease.

INTRODUCTION: Lipoprotein (a) [Lp(a)] is a risk factor for coronary artery disease (CAD). To the best of our knowledge, this is the first study addressing the relationship between Lp(a) and platelet reactivity in primary and secondary prevention. METHODS: Lp(a) was evaluated in 396 individuals with (82.3%) and without (17.7%) obstructive CAD. The population was divided into two groups according to Lp(a) concentrations with a cutoff value of 50 mg/dL. The primary objective was to evaluate the association between Lp(a) and adenosine diphosphate (ADP)-induced platelet reactivity using the VerifyNow™ P2Y12 assay. Platelet reactivity was also induced by arachidonic acid and collagen-epinephrine (C-EPI) and assessed by Multiplate™, platelet function analyzer™ 100 (PFA-100), and light transmission aggregometry (LTA) assays. Secondary objectives included the assessment of the primary endpoint in individuals with or without CAD. RESULTS: Overall, 294 (74.2%) individuals had Lp(a) < 50 mg/dL [median (IQR) 13.2 (5.8-27.9) mg/dL] and 102 (25.8%) had Lp(a) ≥ 50 mg/dL [82.5 (67.6-114.5) mg/dL], P < 0.001. Univariate analysis in the entire population revealed no differences in ADP-induced platelet reactivity between individuals with Lp(a) ≥ 50 mg/dL (249.4 ± 43.8 PRU) versus Lp(a) < 50 mg/dL (243.1 ± 52.2 PRU), P = 0.277. Similar findings were present in individuals with (P = 0.228) and without (P = 0.669) CAD, and regardless of the agonist used or method of analysis (all P > 0.05). Finally, multivariable analysis did not show a significant association between ADP-induced platelet reactivity and Lp(a) ≥ 50 mg/dL [adjusted OR = 1.00 [(95% CI 0.99-1.01), P = 0.590]. CONCLUSION: In individuals with or without CAD, Lp(a) ≥ 50 mg/dL was not associated with higher platelet reactivity.