Smoking and outcomes following guided de-escalation of antiplatelet treatment in acute coronary syndrome patients: a substudy from the randomized TROPICAL-ACS trial

Aims

Prior analyses disclosed variations in antiplatelet drug response and clinical outcomes between smokers and non-smokers, thus the safety and efficacy of any dual antiplatelet therapy (DAPT) de-escalation strategy may differ in relation to smoking status. Hence, we assessed the impact of smoking on clinical outcomes and adenosine diphosphate-induced platelet aggregation following guided de-escalation of DAPT in invasively managed acute coronary syndrome (ACS) patients.

Methods and results

The multicentre TROPICAL-ACS trial randomized 2610 biomarker-positive ACS patients 1:1 to standard treatment with prasugrel for 12 months (control group) or a platelet function testing guided de-escalation of DAPT. Current smokers (n = 1182) showed comparable event rates between study groups [6.6% vs. 6.6%; hazard ratio (HR) 1.0, 95% confidence interval (CI) 0.64–1.56, P > 0.99]. In non-smokers (n = 1428), a guided DAPT de-escalation was associated with a lower 1-year incidence of the primary endpoint [cardiovascular death, myocardial infarction, stroke, or bleeding ≥ Grade 2 according to Bleeding Academic Research Consortium (BARC) criteria] compared with control group patients (7.9% vs. 11.0%; HR 0.71, 95% CI 0.50–0.99, P = 0.048). This reduction was mainly driven by a lower rate of BARC ≥ Grade 2 bleedings (5.2% vs. 7.7%; HR 0.68, 95% CI 0.45–1.03, P = 0.066). There was no significant interaction of smoking status with treatment effects of guided DAPT de-escalation (Pint = 0.23). Adenosine diphosphate-induced platelet aggregation values were higher in current smokers [median 28 U, interquartile range (IQR: 20–40)] vs. non-smoker [median 24 U (16–25), P < 0.0001] in the control group and in current smokers [median 42 U, IQR (27–68)] vs. non-smoker [median 37 U, IQR (25–55), P < 0.001] in the monitoring group.

Conclusion

Guided DAPT de-escalation appears to be equally safe and effective in smokers and non-smokers. Regardless of smoking status and especially for those patients deemed unsuitable for 1 year of potent platelet inhibition this DAPT strategy might be used as an alternative antiplatelet treatment regimen.

Age and outcomes following guided de-escalation of antiplatelet treatment in acute coronary syndrome patients undergoing percutaneous coronary intervention: results from the randomized TROPICAL-ACS trial

Aims

Guided de-escalation of P2Y12-inhibitor treatment was recently identified as an effective alternative treatment strategy in acute coronary syndrome (ACS) patients undergoing percutaneous coronary intervention. Safety and efficacy of this strategy may differ in relation to patient's age. This pre-specified analysis of the TROPICAL-ACS trial aimed to assess the impact of age on clinical outcomes following guided de-escalation of antiplatelet treatment in ACS patients.

Methods and results

Patients were randomly assigned in a 1:1 fashion to either standard treatment with prasugrel for 12 months (control group) or to a guided de-escalation regimen (1 week prasugrel followed by 1 week clopidogrel and platelet function testing guided maintenance therapy with clopidogrel or prasugrel from day 14 after hospital discharge; guided de-escalation group). We used Cox regression models to assess the associations of age on clinical endpoints and interactions. In younger patients (age ≤70, n = 2240), the 1 year incidence of the primary endpoint (cardiovascular death, myocardial infarction, stroke, or bleeding ≥ grade 2 according to Bleeding Academic Research Consortium criteria) was significantly lower in guided de-escalation vs. control group [5.9% vs. 8.3%; hazard ratio (HR) 0.70, 95% confidence interval (CI) 0.51-0.96; P = 0.03, number needed to treat = 42]. In elderly patients (age >70, n = 370), the absolute risk of events was higher without significant differences between guided de-escalation vs. control group (15.5% vs. 13.6%; HR 1.17, 95% CI 0.69-2.01; P = 0.56). When the impact of age, as a continuous variable, was analysed on outcomes after guided de-escalation vs. control treatment, an increasing relative risk reduction was observed in the primary endpoint by decreasing age (Pint = 0.02), due to significant reductions in bleeding.

Conclusion

Treatment effects of guided de-escalation for P2Y12 inhibitors depend on patient's age with younger patients deriving a significant net clinical benefit. Although the safety and efficacy of guided de-escalation in the elderly was similar to uniform prasugrel therapy, this should be further investigated due to the limited sample size of this group.

252Guided de-escalation of antiplatelet treatment in patients with acute coronary syndrome and multivessel coronary artery disease: a post-hoc analysis of the TROPICAL-ACS trial

Background

The TROPICAL-ACS trial showed that platelet function testing (PFT) guided de-escalation of P2Y12-inhibitor is a safe alternative treatment strategy in patients with acute coronary syndrome (ACS) undergoing percutaneous coronary intervention (PCI). No specific data are available on the efficacy of this strategy in patients with multivessel coronary artery disease (CAD).

Purpose

To investigate the safety and efficacy of guided de-escalation of P2Y12-inhibitor treatment in patients with multivessel CAD.

Methods

Two-thousand six-hundred-two biomarker-positive ACS patients were 1:1 randomized to either conventional treatment with prasugrel for 12 months (control group) or to a PFT guided de-escalation treatment strategy (guided de-escalation group). The primary endpoint (net clinical benefit) was defined as the composite of cardiovascular mortality (CVM), myocardial infarction (MI), stroke, and clinically overt bleeding (bleeding ≥ grade 2 according to the BARC criteria). The ischemic endpoint was defined as the composite of CVM, MI or stroke. We used log-rank statistics and Cox regression analysis with interaction testing to assess the effect of multivessel CAD on the primary and ischemic endpoints.

Results

Patients with multivessel (n=709) versus single-vessel CAD (n=1,901) exhibited a higher risk for the primary endpoint (10.2% vs. 7.6%; HR 1.36; 95% CI 1.02–1.81; p=0.034). Guided de-escalation was non-inferior to conventional treatment for the primary endpoint in both patients with single-vessel CAD (6.7% vs. 8.5%; pnon-inferiority = 0.001; Figure 1A) and multivessel CAD (9,5% vs. 10.9%; pnon-inferiority=0.041; Figure 1B). Moreover, there was no significant interaction in the prognostic value of guided de-escalation between single-vessel and multivessel CAD for both the primary (HR 0.78 [0.56–1.08]; p=0.137 in patients with single-vessel CAD vs. 0.86 [0.54–1.37; p=0.524 in patients with multivessel CAD; pinteraction=0.732) and combined ischemic endpoints (HR 0.80 [0.44–1.45]; p=0.456 in patients with single-vessel CAD vs. 0.71 [0.35–1. 46]; p=0.356 in patients with multivessel CAD; pinteraction=0.823).

Kaplan-Meier curves

Conclusion

A guided de-escalation of P2Y12-inhibitor appears to be safe and effective in ACS patients with both single-vessel and multivessel CAD.

Acknowledgement/Funding

Klinikum der Universität München, Roche Diagnostics, Eli Lilly, and Daiichi Sankyo.

Diabetes and outcomes following guided de-escalation of antiplatelet treatment in acute coronary syndrome patients undergoing percutaneous coronary intervention: a pre-specified analysis from the randomised TROPICAL-ACS trial

AIMS

A guided de-escalation of P2Y12 inhibitor treatment is considered an alternative treatment strategy in ACS patients undergoing PCI. However, the safety and efficacy of this strategy may differ in diabetic vs non-diabetic patients. The aim of this study was to compare the outcomes of platelet function testing (PFT)-guided de-escalation of dual antiplatelet therapy (DAPT) in ACS patients with and without diabetes mellitus.

METHODS AND RESULTS

The TROPICAL-ACS trial randomised 2,610 biomarker-positive ACS patients 1:1 to either standard treatment with prasugrel for 12 months (control group) or PFT-guided DAPT de-escalation. The association and interaction of diabetes on clinical endpoints across treatment groups and on platelet reactivity was investigated. In diabetic patients (n=527, 20.2%), the overall event rates were high and the one-year incidence of the primary endpoint (cardiovascular death, myocardial infarction, stroke or bleeding ≥grade 2) did not differ between guided de-escalation and control group patients (12.5% vs 10.8%; HR 1.17, 95% CI: 0.71-1.93, p=0.55). In non-diabetic patients (n=2,083, 79.8%), the one-year incidence of the primary endpoint was lower in the guided de-escalation vs control group (6.1% vs 8.5%; HR 0.71, 95% CI: 0.52-0.99, p=0.04, pint=0.10). Diabetic patients showed higher platelet reactivity levels in both control (=on prasugrel, p=0.01) and guided de-escalation group (=on clopidogrel, p=0.005) patients.

CONCLUSIONS

Although diabetic status did not significantly interfere with the treatment effects of guided DAPT de-escalation, our results suggest that this approach might be safe and effective in non-diabetic patients. Further investigation is definitely warranted in diabetic patients.

Gender and Outcomes following Guided De-Escalation of Antiplatelet Treatment in Acute Coronary Syndrome Patients: The TROPICAL-ACS Gender Substudy

OBJECTIVES

 This prespecified analysis of the TROPICAL-ACS trial aimed to assess the impact of gender on clinical outcomes and platelet reactivity (PR) following guided de-escalation of dual antiplatelet treatment (DAPT) in acute coronary syndrome (ACS) patients.

BACKGROUND

 Guided de-escalation of DAPT was recently identified as an effective alternative treatment strategy in ACS.

METHODS

 We used Cox proportional hazards models and linear regression analysis to assess the interaction of gender with clinical endpoints and PR.

RESULTS

 In both male (n = 2,052) and female (n = 558) patients, the 1-year incidence of the primary endpoint did not differ in guided de-escalation versus control group patients (male: 7.0% vs. 9.0%; hazard ratio [HR], 0.78, 95% confidence interval [CI], 0.57-1.06, p = 0.11; female: 8.4% vs. 9.2%; HR, 0.92, 95% CI, 0.53-1.62, p = 0.76, p _int= 0.60). The 1-year incidence of combined ischemic events (male: 2.5% vs. 3.3%; HR, 0.76, 95% CI, 0.46-1.26, p = 0.29; female: 2.2% vs. 2.8%; HR, 0.78,95% CI, 0.27-2.25, p = 0.65, p _int= 0.96) as well as Bleeding Academic Research Consortium ≥ 2 bleeding (male: 4.6% vs. 6.0%; HR, 0.77, 95% CI, 0.52-1.12, p = 0.17; female: 6.2% vs. 6.4%; HR, 0.99, 95% CI, 0.51-1.92, p = 0.97, p _int= 0.51) was similar in the guided de-escalation versus control group for both male and female patients. Interaction testing revealed no significant impact of gender on PR levels (prasugrel or clopidogrel) across treatment groups (p _int = 0.72).

CONCLUSION

 Guided de-escalation of DAPT appears to be equally safe and effective in women and men. Especially in patients with increased bleeding risk and independent from gender, a guided DAPT de-escalation strategy may be used as an alternative treatment strategy.

CLINICAL TRIAL REGISTRATION

 URL: https//www.clinicaltrials.gov. Unique Identifier: NCT: 01959451.

Genotype-Phenotype Association and Impact on Outcomes following Guided De-Escalation of Anti-Platelet Treatment in Acute Coronary Syndrome Patients: The TROPICAL-ACS Genotyping Substudy

BACKGROUND

 Phenotype-guided de-escalation (PGDE) of P2Y₁₂-inhibitor treatment with an early switch from prasugrel to clopidogrel was identified as an effective alternative treatment strategy in acute coronary syndrome (ACS) patients undergoing percutaneous coronary intervention (PCI). The Testing Responsiveness to Platelet Inhibition on Chronic Antiplatelet Treatment for Acute Coronary Syndromes (TROPICAL-ACS) Genotyping Substudy aimed to investigate whether CYP2C19 genotypes correlate with on-treatment platelet reactivity (PR) in ACS patients treated with clopidogrel or prasugrel and thus might be useful for guidance of early de-escalation of anti-platelet treatment.

METHODS AND RESULTS

 A total of 603 ACS consecutive patients were enrolled in four centres (23.1% of the overall TROPICAL-ACS population). Rapid genotyping (Spartan RX) for CYP2C19*2, *3 and *17 alleles was performed. Associations between PR and the primary and secondary endpoints of the TROPICAL-ACS trial and CYP2C19*2 and CYP2C19*17 carrier status were evaluated.For the PGDE group, the on-clopidogrel PR significantly differed across CYP2C19*2 (p < 0.001) and CYP2C19*17 genotypes (p = 0.05). Control group patients were not related (p = 0.90, p = 0.74) to on-prasugrel PR. For high PR versus non-high PR patients within the PGDE group, significant differences were observed for the rate of CYP2C19*2 allele carriers (43% vs. 28%, p = 0.007).

CONCLUSION

 CYP2C19*2 and CYP2C19*17 carrier status correlates with PR in ACS patients treated with clopidogrel and thus might be useful for pre-selecting patients who will and who may not be suitable for PGDE of anti-platelet treatment. Regarding phenotype-guided treatment, we did not observe added benefit of genotyping to predict ischaemic and bleeding risk in patients who underwent a PGDE approach.

CLINICAL TRIAL REGISTRATION

 URL: https//www.clinicaltrials.gov. Unique Identifier: NCT: 01959451.

A randomised trial on platelet function-guided de-escalation of antiplatelet treatment in ACS patients undergoing PCI

Outcomes of acute coronary syndrome (ACS) patients undergoing percutaneous coronary intervention (PCI) have been significantly improved with the use of potent P2Y12 receptor inhibitors like prasugrel. While most of the ischaemic risk reduction for prasugrel versus clopidogrel was demonstrated in the early treatment period, the risk of bleeding became particularly prominent during the chronic course of therapy. It may therefore be a valid approach to substitute prasugrel for clopidogrel in the early phase of chronic antiplatelet treatment after PCI. In the Testing Responsiveness To Platelet Inhibition On Chronic Antiplatelet Treatment For Acute Coronary Syndromes (TROPICAL-ACS) trial, we aim to compare standard prasugrel therapy with a de-escalating antiplatelet treatment approach guided by platelet function testing (PFT). The study is an investigator-initiated European multicentre, randomised clinical trial in biomarker-positive ACS patients after successful PCI. Two thousand six hundred patients will be randomised prior to hospital discharge in a 1:1 fashion to either receive standard prasugrel therapy (control group) or de-escalating therapy (one-week prasugrel followed by one-week clopidogrel and PFT-guided maintenance therapy from day 14 after hospital discharge, monitoring group). Patients of the monitoring group with high on-clopidogrel platelet reactivity (HPR) based on Multiplate analyzer testing (HPR: ≥ 46U per consensus definition) will be switched back to prasugrel, whereas those without HPR (<46 U) will continue clopidogrel treatment. The overall study treatment duration will be one year in both groups. The primary endpoint of the study is net clinical benefit (combined incidence of cardiovascular death, myocardial infarction, stroke and bleeding ≥ grade 2 according to BARC criteria) one-year after randomisation. TROPICAL-ACS is the first large-scale, randomised controlled trial assessing the clinical value of a PFT-guided de-escalation of antiplatelet treatment in biomarker positive ACS patients undergoing PCI.

ClinicalTrials.gov Identifier: NCT01959451

Randomised comparison of titanium-nitride-oxide coated stents with bare metal stents: five year follow-up of the TiNOX trial

AIMS

Revascularisation with Titanium-Nitride-Oxide (TiNOX) coated stents is safe and effective in patients with de novo native coronary artery lesions. In the TiNOX trial there was a reduction in restenosis and major adverse cardiac events as compared with stainless steel stents of otherwise identical design. The purpose of the present study was to evaluate the long-term outcome of these patients over five years.

METHODS AND RESULTS

In 2003, 92 patients with de novo lesions were randomly assigned to treatment with TiNOX coated stents (n=45) or stainless steel stents (n=47; control). Baseline characteristics were similar in both groups. Follow-up at six months and five years was obtained in 87 patients. Five patients were lost to follow-up due to emigration or change in home address. At six months and five years, significantly less major adverse cardiac events (MACE) occurred in the TiNOX group (7% vs. 27%, [p=0.02] respectively and 16% vs. 39%, [p=0.03]), largely driven by a reduced need for target-lesion revascularisation. No stent thrombosis occurred in the TiNOX group vs. one in the control group. Patients in the TiNOX-group had lower all-cause mortality and less myocardial infarction, but the difference was not statistically significant.

CONCLUSIONS

Five-year follow-up after implantation of titanium-nitride-oxide coated stents is favourable with a low rate of MACE and no stent thrombosis compared to bare metal stents of identical design. The need for revascularisation at five years was 9% in the TiNOX and 25% in the control group with little progression of native coronary disease.

The validation of fractional flow reserve in patients with coronary multivessel disease: a comparison with SPECT and contrast-enhanced dobutamine stress echocardiography

Fractional flow reserve (FFR) is a new but well established parameter for the hemodynamic evaluation of coronary stenoses. A FFR below 0.75 was validated as functionally significant in coronary one or two vessel disease. This study was designed to prospectively define the best FFR cut off value (BCV) in patients with multivessel disease using two noninvasive tests, myocardial perfusion scintigraphy (SPECT) and contrast-enhanced dobutamine stress echocardiography (DSE) as reference methods.

METHODS

47 symptomatic patients (29 male, mean age 64+/-10 yrs) with angiographically intermediate coronary lesions (50-75% diameter stenosis) entered the study. DSE (5-40 microg/min/kg dobutamine) was performed after intravenous injection of a second generation transpulmonary contrast agent. SPECT (Tc-99m-MIBI) was done at peak stress. All tests (DSE, SPECT and FFR) were performed within 4 weeks.

RESULTS

SPECT yielded positive results in 15 and DSE in 16 patients, respectively. Mean FFR measured in the target lesion (RCA n=10; LAD n=22, RCX n=15) was 0.80+/-0.13. FFR was <0.75 in 15 patients. By performing a ROC analysis the BCV (highest sum of sensitivity and specificity) was found at 0.75. At this cut off value using both non-invasive tests as reference method, sensitivity and specificity were 83 and 77%.

CONCLUSION

In patients with multivessel disease, a FFR <0.75 identifies a hemodynamically relevant lesion as compared to DSE and SPECT. This study underlines that FFR criteria are also applicable in patients with complex coronary artery disease.

Fractional flow reserve for the prediction of cardiac events after coronary stent implantation: results of a multivariate analysis

OBJECTIVE

To determine the prognostic value of fractional flow reserve (FFR) measurements after coronary stent implantation including multiple clinical and angiographic parameters collected in one centre.

METHODS

119 consecutive patients were enrolled who had a stent implanted with the use of a pressure wire as a guidewire. Patients were followed up for at least six months. Any death, myocardial infarction, and target vessel revascularisation were considered major adverse cardiac events (MACE). Multivariate logistic regression was used to determine adjusted odds ratios (OR) and 95% confidence intervals (CI) for FFR and covariates.

RESULTS

Complete follow up data were available for all 119 patients. Pre-interventional FFR increased from 0.65 (0.15) to 0.94 (0.06) (p < 0.0001) after stent implantation. Eighteen MACE (15%) occurred during follow up including 15 (12.6%) target vessel revascularisations. Final FFR was significantly higher in patients without than in patients with an event (0.95 (0.05) v 0.88 (0.08), p = 0.001). In the multivariate logistic regression analysis, only final FFR < 0.95 (OR 6.22, 95% CI 1.79 to 21.62, p = 0.004) and reduced left ventricular function (OR 0.95, 95% CI 092 to 0.99, p = 0.021) remained as significant independent predictors for MACE.

CONCLUSION

These results including multiple parameters underline that FFR after coronary stenting is a strong and independent predictor for subsequent cardiac events after six months' follow up.

Fractional flow reserve predicts major adverse cardiac events after coronary stent implantation

OBJECTIVES

Determination of fractional flow reserve (FFR) allows the functional assessment of coronary stenoses before and after an intervention. Preliminary data suggest that a FFR > or = 0.94 is associated with an excellent clinical outcome after stent implantation. However, these results were limited both by the number of patients included and the use of non-contemporary stent designs. We sought to determine the prognostic value of FFR measurements in a large patient cohort undergoing coronary stent implantation.

METHODS

Eighty-nine consecutive patients were enrolled in whom a stent implantation was performed and a pressure wire was used as a guide wire. Patients were followed for at least 6 months. Death, myocardial infarction (MI) and target vessel revascularization (TVR) were considered cardiac events. A FFR > or = 0.94 was regarded as an optimal functional result.

RESULTS

A complete follow-up was available in all patents. Pre-interventional FFR increased from 0.66 +/- 0.16 to 0.95 +/- 0.05 (p < 0.0001) after stent implantation. Sixteen (18%) events occurred during follow-up including 10 (11.2%) TVR. Final FFR was significantly higher in patients without compared to patients with an event (0.92 +/- 0.06 vs. 0.96 +/- 0.05, p < 0.003). By univariate analysis, the presence of diabetes mellitus, left ventricular function, residual diameter stenosis and final FFR were associated with a worse clinical outcome. In the multivariate analysis, only the final FFR and left ventricular function remained as significant predictors for cardiac events (relative risk, 3.50; 95% CI: 1.29-9.52, P < 0.014, and 0.97; 95% CI: 0.93-1.00, p = 0.047).

CONCLUSION

These results demonstrate in a nonselected patient cohort a strong correlation between FFR values after coronary stenting and subsequent cardiac events. Further studies have to investigate whether outcome after stenting might be improved by guiding the procedure with a pressure guide wire.