M. Mendes

Prognostic value of electrocardiogram exercise testing for risk stratification in asymptomatic coronary artery disease

Background Several variables of electrocardiogram exercise testing (EET) predict cardiovascular events in the general population and in patients with coronary artery disease (CAD). However, most of the studies have not included patients with asymptomatic CAD. The aim of this study was to evaluate the prognostic value of EET in asymptomatic CAD patients. Patients and methods We carried out a retrospective single-center analysis including all patients with asymptomatic CAD documented by angiography who underwent EET from January 2010 to December 2013. A number of EET variables and three exercise scores [Duke Treadmill Score (DTS), Morise score, and FIT score] were analyzed. The primary endpoint was the combined incidence of myocardial infarction (MI), myocardial revascularization, and death from any cause during follow-up. Results A total of 306 patients were included (mean age was 65±10 years, 61% had previous MI, and the median exercise capacity was 9.4±2.7 metabolic equivalent of task). The primary endpoint occurred in 15.7% of patients during 3.3 years of follow-up. The DTS and FIT were independent predictors of the primary endpoint unlike the Morise score (DTS: hazard ratio=0.91, 95% confidence interval: 0.85–0.99, P=0.018; FIT score: 0.99, 0.98–0.996, P=0.001; Morise score: 0.97, 0.93–1.02, P=0.20). The DTS was independent predictor of MI or revascularization, whereas FIT predicted death from any cause. Excluding patients with early revascularization, DTS had no predictive power at the composite endpoint. Conclusion In our population with asymptomatic CAD, FIT and DTS had significant value for risk prediction and consequently the EET can be a valid tool in the clinical follow-up of this population.

PS-047 Co-prescription of simvastatin and potent inhibitors of CYP3A4; monitoring system in hospital

Background Drug-drug interactions may increase the risk of adverse events. Understanding the pharmacokinetic and pharmacodynamic properties of drugs and their interaction mechanisms is fundamental to optimising therapeutic results. The benefits of statins in the treatment and prevention of cardiovascular disease are well documented. Although overall safe, statins produce a wide range of adverse effects that are known to be potentiated by certain drug interactions. Concomitant use of simvastatin with a potent CYP3A4 inhibitor (inCYP3A4) is considered a clinically significant pharmacokinetic interaction, and therefore this combination is contraindicated. Purpose To evaluate the efficacy of a recently implemented safety alerts system in reducing the prevalence of co-prescription of simvastatin and inCYP3A4. Materials and methods After an extensive bibliographic review of the drug interaction classifications, a computerised system was implemented to alert for the risk of co-prescription of simvastatin and an inCYP3A4. All patients with a simvastatin prescription admitted to Centro Hospitalar de Lisboa Ocidental, between April 2013 – October 2013, were included. Data were obtained by consulting the Pharmaceutical Services’ records. Co-prescription prevalence rates were assessed for a three-month period, before and after implementation of safety alerts. Results In this study, 1707 patients (55.4% male, mean age 72.7 ± 12.2 [27–103] years) were included in pre-implementation phase (PEP) and 1225 patients (56.0% male, mean age 72.3 ± 12.6 [15–105] years) in the post-implementation phase (POP). In PEP, co-prescription was identified in 110 patients (mean duration 4.9 ± 7.1 days, [1–65]) and in POP, 13 patients (mean duration 3.8 ± 3.9 days, [1–15]). Co-prescription rates in PEP and POP were 6.44% and 1.06% respectively, which represents an 83.53% reduction. Conclusions The safety alerts system implemented seems to be an effective strategy in reducing incidence of simvastatin and inCYP3A4 co-prescription, and therefore may increase patient safety in hospital. Our study will be extended to a one-year period (January 2013–2014) in order to evaluate the robustness of the implemented strategy. No conflict of interest.

Can we improve duration of hospital stay in angioplasty treated ST-segment elevation acute myocardial infarction? The Zwolle risk score

Purpose: Optimal duration of stay (DS) in angioplasty (PCI) treated uncomplicated acute ST-segment elevation myocardial infarction (STEMI) remains undetermined. The Zwolle risk score (ZRS) is a simple tool which could help identify patients who can be safely discharged before 72h. We aimed to apply ZRS to our population and assess the variables influencing DS. Methods: 276 consecutive STEMI patients admitted for PCI were studied, between January 2009 and December 2010. ZRS, DS and 30-day mortality were obtained for all patients. Low risk was defined as ZRS≤3 and ROC curves were used for discriminative power. Results: In the 276 patients evaluated (mean age 62±13 years-old, 75% male, 20% Killip>1), ZRS median was 3 (IQR 1-4). 171 patients were classified as low risk. These patients were younger (57.1 vs. 67.6 years-old, p 1.2 mg/dL (37.2 vs 62.8% p=0.001). Total 30-day mortality was 4.7% (13 patients). ZRS correctly predicted this event in 93.7% of cases (C-statistic 0.937; CI95% 0.906-0.968). 30-day mortality, stratified by ZRS, was significantly different in the 2 groups (0 vs. 12.4% p<0.001, Fig.1), corresponding to a positive predictive value of 100% (CI95% 97.0-100%) for safe early discharge. In the low risk subset of patients, mean duration of stay was substantially lower (6.0 vs. 15.1 days, p<0.001). The need for additional revascularization (20 patients, 11.7%) was the most frequent cause for longer DS. ![Figure][1] Figure 1 Conclusions: In our population, a ZRS ≤3 had both high discriminative power and positive predictive value for safe early discharge, translating on the DS. A cost-benefit analysis is warranted to further assess the real impact of these results. [1]: pending:yes