Social deprivation index and ischemic events after percutaneous coronary intervention in patients with diabetes mellitus.

The aim of this study was to assess neighborhood-based differences in outcomes of diabetics versus non-diabetics undergoing percutaneous coronary interventions. Disparities in healthcare access impact long-term outcomes in safety net populations. Diabetes mellitus (DM) is associated with worse clinical outcomes in patients with coronary artery disease (CAD) and may disproportionately impact patients with CAD from underserved populations. We created a geocoded retrospective cohort of patients who underwent percutaneous coronary intervention (PCI) at an urban safety net hospital in this single-center cohort analysis. We evaluated long-term ischemic events in diabetics versus nondiabetics through review of electronic medical records. Social deprivation index (SDI) was calculated based on US-census tract level and stratified according to quintiles. Among 1002 patients, 46% (n = 463) were diabetic and among those 48% (n = 222) were in the highest quintile of SDI. Baseline and angiographic characteristics were similar among diabetic and nondiabetic subjects. Among diabetic patients, those in the highest SDI quintile had significantly higher risk of cardiovascular death and myocardial infarction as compared to those in the remaining quintiles (log rank: p = 0.029) (adjusted hazard's ratio: 1.72 [95% CI: 1.01-2.92], p = 0.04). There was no association of the SDI with outcomes in nondiabetic patients (log rank: p = 0.39). In an underserved population, patients with diabetes and high SDI demonstrate higher rates of adverse ischemic events and cardiovascular death during long-term follow up after PCI. Further research examining the impact of disparities in healthcare access on outcomes after PCI in patients with diabetes is warranted.

Impact of Routine Platelet Reactivity Testing with VerifyNow Assay on Antiplatelet Choice After Percutaneous Coronary Intervention.

BACKGROUND: High on-treatment ADP platelet reactivity (HPR) measured by VerifyNow P2Y12 assay (VN) is an established risk factor for ischemic events after percutaneous coronary intervention (PCI). We hypothesized that routine use of VN at time of PCI in clinical practice may affect choice of P2Y12 antiplatelet therapy at discharge. METHODS: In a single center retrospective analysis, we examined the influence of VN testing on choice of P2Y12 inhibitor post PCI in routine clinical practice. Assessment of HPR was used routinely in clinical care during the time period of analysis at discretion of clinical providers. Subjects with PRU>208 after the loading dose of clopidogrel or during clopidogrel steady state were switched to alternate P2Y12 inhibitors. RESULTS: We identified 1001 patients with PCI during the time period specified. A total of 252 subjects underwent VN testing. Among those, 43% were found to have HPR on clopidogrel and were switched to alternate therapies (prasugrel [n=60], ticagrelor [n=48]). Patients who had VN platelet function testing were more likely to be discharged on clopidogrel as compared to those who did not have VN assay done (57% vs. 50%, p=0.039). There was no significant difference in 1-year net-MACE (CVD, MI, stent thrombosis, BARC 2 or higher bleeding) using tailored antiplatelet therapy (VN testing) as compared to standard of care group (adjusted HR:0.92, 95% CI: 0.54-1.5, p=0.74). CONCLUSION: Routine use of VN assay in personalized antiplatelet treatment decision-making after PCI is associated with lower likelihood of using novel P2Y12 inhibitors.

Intensified P2Y12 inhibition for high-on treatment platelet reactivity.

High on treatment platelet reactivity (HPR) during treatment with clopidogrel has been consistently found to be strong risk factor for recurrent ischemic events after percutaneous coronary intervention (PCI). Insufficient P2Y12 receptor inhibition contributes to HPR measured by the VerifyNow (VN) assay. Prasugrel and ticagrelor are more potent P2Y12 inhibitors than clopidogrel and commonly substituted for clopidogrel when HPR is documented, however benefit of VN guided intensified antiplatelet therapy is uncertain. We identified patients who had undergone platelet reactivity testing after PCI with VN after pretreatment with clopidogrel (n = 252) in a single center observational analysis. Patients who had HPR defined as PRU > 208 were switched to alternate P2Y12 inhibitors. Primary clinical endpoint was 1-year post PCI combined cardiovascular death, myocardial infarction (MI), and stent thrombosis. One hundred and eight (43%) subjects had HPR and were switched to prasugrel (n = 60) and ticagrelor (n = 48). Risk of recurrent 1-year primary endpoint remained higher for HPR patients switched to either ticagrelor or prasugrel as compared to subjects who had low on treatment platelet reactivity (n = 144) (LPR) on clopidogrel [Hazard Ratio: 3.5 (95% CI 1.1-11.1); p = 0.036)]. Propensity score matched analysis demonstrated higher event rates in patients with HPR on alternate P2Y12 inhibitor as compared to patients with LPR (log-rank: p = 0.044). The increased risk of recurrent events associated with HPR measured by VN is not completely attenuated by switching to more potent P2Y12 inhibitors. Non-P2Y12 mediated pathways likely contribute to increased incidence of thrombotic events after PCI in subjects with HPR.