Relationship Between Stent Diameter, Platelet Reactivity, and Thrombotic Events After Percutaneous Coronary Artery Revascularization

Resistance on the Latest Oral and Intravenous P2Y12 ADP Receptor Blockers in Patients with Acute Coronary Syndromes: Fact or Myth?

Novel P2Y12 ADP receptor blockers (ADPRB) should be preferred in dual-antiplatelet therapy in patients with acute coronary syndrome. Nevertheless, there are still patients who do not respond optimally to novel ADP receptor blocker therapy, and this nonoptimal response (so-called "high on-treatment platelet reactivity" or "resistance") could be connected with increased risk of adverse ischemic events, such as myocardial re-infarction, target lesion failure and stent thrombosis. In addition, several risk factors have been proposed as factors associated with the phenomenon of inadequate response on novel ADPRB. These include obesity, multivessel coronary artery disease, high pre-treatment platelet reactivity and impaired metabolic status for prasugrel, as well as elderly, concomitant therapy with beta-blockers, morphine and platelet count for ticagrelor. There is no literature report describing nonoptimal therapeutic response on cangrelor, and cangrelor therapy seems to be a possible approach for overcoming HTPR on prasugrel and ticagrelor. However, the optimal therapeutic management of "resistance" on novel ADPRB is not clear and this issue requires further research. This narrative review article discusses the phenomenon of high on-treatment platelet reactivity on novel ADPRB, its importance in clinical practice and approaches for its therapeutic overcoming.

Coronary Stenting in High Bleeding Risk Patients With Small Coronary Arteries Followed by One-Month Dual Antiplatelet Therapy: Onyx ONE Clear

Background

Small reference vessel diameters (RVDs) are a predictor of ischemic events after coronary stenting. Among patients at high bleeding risk (HBR) precluding long-term dual antiplatelet therapy (DAPT), those with small vessel disease (SVD) constitute an especially high-risk subgroup. Here, we evaluated the results of a durable-polymer, coronary zotarolimus-eluting stent (ZES) for the treatment of patients with SVD at HBR with 1-month DAPT.

Methods

In the prospective, multicenter Onyx ONE (One-Month DAPT) Clear study, 1506 patients at HBR treated with a ZES that discontinued DAPT at 30 days were included. The clinical outcomes of patients undergoing treatment of lesions with an RVD of ≤2.5 mm (SVD group, as determined by the angiographic core laboratory) were compared with patients without SVD. The primary end point was the composite of cardiac death or myocardial infarction between 1 and 12 months.

Results

Small vessel diameter treatment was performed in 489 (32.5%) patients. Patients with SVD were more likely to be women, have undergone a previous percutaneous intervention, and have multivessel coronary artery disease than patients without SVD. There were no significant differences in lesion, device, or procedural success between the groups. The Kaplan-Meier rate estimate of the primary end point was 8.5% and 6.8% in patients with SVD and those without SVD, respectively (P = .425). No significant differences were found in any secondary end point. The Kaplan-Meier rate of stent thrombosis was 0.6% and 0.8% in patients with SVD and those without SVD, respectively (P = .50).

Conclusions

Among patients at HBR treated with a ZES and 1-month DAPT, those with SVD had favorable 12-month ischemic and bleeding outcomes, which were comparable with those of patients with larger caliber vessels.

1-Year Outcomes with COMBO Stents in Small-Vessel Coronary Disease: Subgroup Analysis From the COMBO Collaboration

BACKGROUND

Small vessel diameter is associated with higher risk of target lesion revascularization (TLR) after percutaneous coronary intervention (PCI). The COMBO sirolimus-eluting biodegradable-polymer stent has a proprietary anti-CD34 antibody layer to enhance homogeneous endothelialization, which may be advantageous in treating small vessels.

OBJECTIVE

We examined for differences in 1-year clinical outcomes after PCI by maximum implanted stent diameter from the COMBO collaboration.

METHODS

The COMBO collaboration (n = 3614) is a patient-level pooled dataset of patients undergoing PCI with COMBO stents in the MASCOT and REMEDEE multicenter registries. Stent diameter was available in 3590 (99.3%) patients. We compared patients receiving COMBO stents <3 mm versus ≥3 mm. The primary endpoint was 1-year target lesion failure (TLF), composite of cardiac death, target vessel-myocardial infarction (TV-MI) or clinically driven TLR. Secondary outcomes included stent thrombosis (ST). Adjusted outcomes were assessed using Cox regression methods.

RESULTS

The study included 792 (22%) patients with small stents <3 mm and 2798 (78%) patients with large stents ≥3 mm. Small stent patients included more women with lower body mass index and higher prevalence of diabetes but similar prevalence of acute coronary syndrome. Risk of 1-year TLF was similar in small and large stent groups (4.4% vs. 3.8%, HR 1.12, 95% CI 0.74-1.72, p = 0.58). There were no differences in the rates of cardiac death (1.7% vs. 1.5%, p = 0.74), TV-MI (1.4% vs. 1.2%, p = 0.58) or TLR (2.7% vs. 2.1%, p = 0.31). Definite or probable ST occurred in 1.3% of the small stent and 0.7% of the large stent PCI patients, p = 0.14, HR 2.13, 95% CI 0.93-5.00, p = 0.07.

CONCLUSIONS

One-year ischemic outcomes after COMBO PCI were similar irrespective of stent diameter in this all-comers international cohort.