Postprocedural anticoagulation for specific therapeutic indications after revascularization for ST-segment elevation myocardial infarction (from the Harmonizing Outcomes with Revascularization and Stents in Acute Myocardial Infarction Trial)

Post-procedural Anticoagulation With Unfractionated Heparin in Acute Coronary Syndrome: Insight from the STOPDAPT-3 Trial

The current guidelines for acute coronary syndrome (ACS) discourage the use of anticoagulation after percutaneous coronary intervention (PCI) without specific indications, although the recommendation is not well supported by evidence. In this post hoc analysis of the ShorT and OPtimal Duration of Dual AntiPlatelet Therapy-3 (STOPDAPT-3) trial, 30-day outcomes were compared between the 2 groups with and without post-PCI heparin administration among patients with ACS who did not receive mechanical support devices. The co-primary end points were the bleeding end point, defined as the Bleeding Academic Research Consortium type 3 or 5 bleeding, and the cardiovascular end point, defined as a composite of cardiovascular death, myocardial infarction, definite stent thrombosis, or ischemic stroke. Among 4,088 patients with ACS, 2,339 patients (57.2%) received post-PCI heparin. The proportion of patients receiving post-PCI heparin was higher among those with ST-elevation myocardial infarction compared with others (72.3% and 38.8%, p <0.001), and among patients with intraprocedural adverse angiographic findings compared with those without (67.6% and 47.5%, p <0.001). Post-PCI heparin compared with no post-PCI heparin was associated with a significantly increased risk of the bleeding end point (4.75% and 2.52%, adjusted hazard ratio 1.69, 95% confidence interval 1.15 to 2.46, p = 0.007) and a numerically increased risk of the cardiovascular end point (3.16% and 1.72%, adjusted hazard ratio 1.56, 95% confidence interval 0.98 to 2.46, p = 0.06). Higher hourly dose or total doses of heparin were also associated with higher incidence of both bleeding and cardiovascular events within 30 days. In conclusion, post-PCI anticoagulation with unfractionated heparin was frequently implemented in patients with ACS. Post-PCI heparin use was associated with harm in terms of increased bleeding without the benefit of reducing cardiovascular events. Trial identifier: STOPDAPT-3 ClinicalTrials.gov number, NCT04609111.

Postprocedural Anticoagulation After Primary Percutaneous Coronary Intervention for ST-Segment-Elevation Myocardial Infarction: A Multicenter, Randomized, Double-Blind Trial

BACKGROUND

Postprocedural anticoagulation (PPA) is frequently administered after primary percutaneous coronary intervention in ST-segment-elevation myocardial infarction, although no conclusive data support this practice.

METHODS

The RIGHT trial (Comparison of Anticoagulation Prolongation vs no Anticoagulation in STEMI Patients After Primary PCI) was an investigator-initiated, multicenter, randomized, double-blind, placebo-controlled, superiority trial conducted at 53 centers in China. Patients with ST-segment-elevation myocardial infarction undergoing primary percutaneous coronary intervention were randomly assigned by center to receive low-dose PPA or matching placebo for at least 48 hours. Before trial initiation, each center selected 1 of 3 PPA regimens (40 mg of enoxaparin once daily subcutaneously; 10 U·kg·h of unfractionated heparin intravenously, adjusted to maintain activated clotting time between 150 and 220 seconds; or 0.2 mg·kg·h of bivalirudin intravenously). The primary efficacy objective was to demonstrate superiority of PPA to reduce the primary efficacy end point of all-cause death, nonfatal myocardial infarction, nonfatal stroke, stent thrombosis (definite), or urgent revascularization (any vessel) within 30 days. The key secondary objective was to evaluate the effect of each specific anticoagulation regimen (enoxaparin, unfractionated heparin, or bivalirudin) on the primary efficacy end point. The primary safety end point was Bleeding Academic Research Consortium 3 to 5 bleeding at 30 days.

RESULTS

Between January 10, 2019, and September 18, 2021, a total of 2989 patients were randomized. The primary efficacy end point occurred in 37 patients (2.5%) in both the PPA and placebo groups (hazard ratio, 1.00 [95% CI, 0.63 to 1.57]). The incidence of Bleeding Academic Research Consortium 3 to 5 bleeding did not differ between the PPA and placebo groups (8 [0.5%] vs 11 [0.7%] patients; hazard ratio, 0.74 [95% CI, 0.30 to 1.83]).

CONCLUSIONS

Routine PPA after primary percutaneous coronary intervention was safe but did not reduce 30-day ischemic events.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT03664180.

Rationale and design of the RIGHT trial: A multicenter, randomized, double-blind, placebo-controlled trial of anticoagulation prolongation versus no anticoagulation after primary percutaneous coronary intervention for ST-segment elevation myocardial infarction

BACKGROUND

Current guidelines recommend anticoagulation therapy during primary percutaneous coronary intervention (pPCI) for ST-segment elevation myocardial infarction (STEMI). However, whether anticoagulation should be continued after pPCI has not been well investigated.

METHODS/DESIGN

The RIGHT trial is a prospective, multicenter, randomized, double-blind, placebo-controlled trial in STEMI patients treated with pPCI evaluating the prolongation of anticoagulation after the procedure. Patients are randomized in a 1:1 fashion to receive either prolonged anticoagulant or matching placebo (no anticoagulation) for at least 48 hours after the procedure. When randomized to anticoagulation prolongation, the patient is assigned to intravenous unfractionated heparin (UFH) or subcutaneous enoxaparin or intravenous bivalirudin (same drug and same regimen at each center). The primary efficacy endpoint is the composite of all-cause death, non-fatal myocardial infarction, non-fatal stroke, stent thrombosis (definite) or urgent revascularization (any vessel) at 30 days. The primary safety endpoint is major bleeding (BARC 3-5) at 30 days. Based on a superiority design and assuming a 35% relative risk reduction (from 7% to 4.5%), 2856 patients will be enrolled, accounting for a 5% drop-out rate (α = 0.05 and power = 80%).

CONCLUSION

The RIGHT trial tests the hypothesis that post-procedural anticoagulation is superior to no anticoagulation in reducing ischemic events in STEMI patients undergoing pPCI.

Post-PCI Antithrombotic Therapy in Patients Requiring Long-Term Anticoagulation

The number of patients who undergo percutaneous coronary intervention (PCI) and additionally require chronic anticoagulation for a variety of indications is not insignificant. The choice of antithrombotic therapy after PCI in patients with chronic indications for anticoagulation therapy remains a challenge for interventional cardiologists, as the risk of bleeding must be adequately weighed against the benefit of preventing future ischemic events. While these clinical scenarios are encountered in approximately 10 % of patients undergoing PCI, current practice guidelines do not sufficiently guide physicians as to how to best treat these PCI patients requiring chronic anticoagulation. Notwithstanding the clinical difficulties of treating such patients, there are several recent studies and analyses that have assessed optimal antithrombotic strategies in the PCI population, and there are several others that are currently underway. This review evaluates the currently available data and clinical scenarios commonly encountered by treating physicians.