Antiplatelet drug selection in PCI to vein grafts in patients with acute coronary syndrome and adverse clinical outcomes: Insights from the British Cardiovascular Intervention Society database

A review of the use of propensity score methods with multiple treatment groups in the general internal medicine literature

BACKGROUND

Propensity score (PS) methods with two treatment groups (e.g., treated vs. control) is a well-established technique for reducing the effects of confounding in nonrandomized studies. However, researchers are often interested in comparing multiple interventions. PS methods have been modified to incorporate multiple exposures. We described available techniques for PS methods in multicategory exposures (≥3 groups) and examined their use in the medical literature.

METHODS

A comprehensive search was conducted for studies published in PubMed, Embase, Google Scholar, and Web of Science until February 27, 2023. We included studies using PS methods for multiple groups in general internal medicine research.

RESULTS

The literature search yielded 4088 studies (2616 from PubMed, 86 from Embase, 85 from Google Scholar, 1671 from Web of Science, five from other sources). In total, 264 studies using PS method for multiple groups were identified; 61 studies were on general internal medicine topics and included. The most commonly used method was that of McCaffrey et al., which was used in 26 studies (43%), where the Toolkit for Weighting and Analysis of Nonequivalent Groups (TWANG) method and corresponding inverse probabilities of treatment weights were estimated via generalized boosted models. The next most commonly used method was pairwise propensity-matched comparisons, which was used in 20 studies (33%). The method by Imbens et al. using a generalized propensity score was implemented in six studies (10%). Four studies (7%) used a conditional probability of being in a particular group given a set of observed baseline covariates where a multiple propensity score was estimated using a non-parsimonious multinomial logistic regression model. Four studies (7%) used a technique that estimates generalized propensity scores and then creates 1:1:1 matched sets, and one study (2%) used the matching weight method.

CONCLUSIONS

Many propensity score methods for multiple groups have been adopted in the literature. The TWANG method is the most commonly used method in the general medical literature.

Contemporary coronary artery bypass graft surgery and subsequent percutaneous revascularization

Patients who have undergone coronary artery bypass graft (CABG) surgery are susceptible to bypass graft failure and progression of native coronary artery disease. Although the saphenous vein graft (SVG) was traditionally the most-used conduit, arterial grafts (including the left and right internal thoracic arteries and the radial artery) have improved patency rates. However, the need for secondary revascularization remains common, and percutaneous coronary intervention (PCI) has become the most common modality of secondary revascularization after CABG surgery. Procedural characteristics and clinical outcomes differ considerably from those associated with PCI in patients without previous CABG surgery, owing to altered coronary anatomy and differences in conduit pathophysiology. In particular, SVG PCI carries an increased risk of complications, and operators are shifting their focus towards embolic protection strategies and complex native-vessel interventions, increasingly using SVGs as conduits to facilitate native-vessel PCI rather than pursuing SVG PCI. In this Review, we discuss the differences in conduit pathophysiology, changes in CABG surgery techniques, and the latest evidence in terms of PCI in patients with previous CABG surgery, with a particular emphasis on safety and long-term efficacy. We explore the subject of contemporary CABG surgery and subsequent percutaneous revascularization in this complex patient population.

Risk of bradyarrhythmia related to ticagrelor: A systematic review and meta-analysis

CONTEXT

Ticagrelor was related to bradycardia in DISPERSE-II trial. This risk has been integrated into the European risk-management plan, and its use is warned in at-risk patients. Nevertheless, this risk was not systematically assessed nor measured.

OBJECTIVES

To estimate the risk of bradyarrhythmia associated with ticagrelor.

STUDY DESIGN

Systematic review and meta-analysis.

DATA-SOURCE

MEDLINE, Scopus, Cochrane Central Register of Controlled Trials, ISI web of Science, clinicaltrial.gov, clinicaltrialsregister.eu.

STUDY SELECTION

Randomized controlled trials (RCTs) and observational studies in patients treated with ticagrelor or comparator(s).

META-ANALYSIS

Risk of bias in each RCT was assessed using Cochrane tool. Relative Risks (RR) with 95 % confidence intervals (95 %CI) were calculated for each RCT, and pooled using fixed-effect or random-effects models, when appropriate. Subgroup and sensitivity analyses were performed. A potential publication bias was searched.

RESULTS

Among 82 eligible studies, event data were missing for 56 studies, due to detected reporting bias (i.e. inability to confirm zero events). Fifteen RCTs were selected and the combined RR of bradyarrhythmia was 1.15 (95 %CI 1.05-1.26), and 1.29 (1.02-1.65) for severe bradyarrhythmia. The risk appeared to be dose dependent. Restricting the analysis only to RCTs performed in patients without previous bradyarrhythmia resulted in a non-increased risk.

CONCLUSION

This meta-analysis confirmed the risk of bradyarrhythmia or severe bradyarrhythmia related to ticagrelor, and its use in patients without previous bradycardia was effective in preventing it. The evidence coming from this meta-analysis was low to moderate due to missing outcome in 2/3 of eligible studies. Waiting for access to these data, the use of ticagrelor in patients with risk factors of bradycardias should be avoided.

Are all P2Y12 equally effective in vein graft angioplasty? A report from the UK database

Information of P2Y12 inhibitors in acute coronary syndromes with vein graft angioplasty is limited. This new analysis from the UK database was not able to find significant differences between Clopidogrel, Prasugrel and Ticagrelor. Large trials would be needed to reliably confirm the best antiplatelet regimen in this setting.