Prognostic Implications of Fractional Flow Reserve After Coronary Stenting:A Systematic Review and Meta-analysis

IMPORTANCE: Fractional flow reserve (FFR) after percutaneous coronary intervention (PCI) is generally considered to reflect residual disease. Yet the clinical relevance of post-PCI FFR after drug-eluting stent (DES) implantation remains unclear. OBJECTIVE: To evaluate the clinical relevance of post-PCI FFR measurement after DES implantation. DATA SOURCES: MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials were searched for relevant published articles from inception to June 18, 2022. STUDY SELECTION: Published articles that reported post-PCI FFR after DES implantation and its association with clinical outcomes were included. DATA EXTRACTION AND SYNTHESIS: Patient-level data were collected from the corresponding authors of 17 cohorts using a standardized spreadsheet. Meta-estimates for primary and secondary outcomes were analyzed per patient and using mixed-effects Cox proportional hazard regression with registry identifiers included as a random effect. All processes followed the Preferred Reporting Items for Systematic Review and Meta-analysis of Individual Participant Data. MAIN OUTCOMES AND MEASURES: The primary outcome was target vessel failure (TVF) at 2 years, a composite of cardiac death, target vessel myocardial infarction (TVMI), and target vessel revascularization (TVR). The secondary outcome was a composite of cardiac death or TVMI at 2 years. RESULTS: Of 2268 articles identified, 29 studies met selection criteria. Of these, 28 articles from 17 cohorts provided data, including a total of 5277 patients with 5869 vessels who underwent FFR measurement after DES implantation. Mean (SD) age was 64.4 (10.1) years and 4141 patients (78.5%) were men. Median (IQR) post-PCI FFR was 0.89 (0.84-0.94) and 690 vessels (11.8%) had a post-PCI FFR of 0.80 or below. The cumulative incidence of TVF was 340 patients (7.2%), with cardiac death or TVMI occurring in 111 patients (2.4%) at 2 years. Lower post-PCI FFR significantly increased the risk of TVF (adjusted hazard ratio [HR] per 0.01 FFR decrease, 1.04; 95% CI, 1.02-1.05; P < .001). The risk of cardiac death or MI also increased inversely with post-PCI FFR (adjusted HR, 1.03; 95% CI, 1.00-1.07, P = .049). These associations were consistent regardless of age, sex, the presence of hypertension or diabetes, and clinical diagnosis. CONCLUSIONS AND RELEVANCE: Reduced FFR after DES implantation was common and associated with the risks of TVF and of cardiac death or TVMI. These results indicate the prognostic value of post-PCI physiologic assessment after DES implantation

Thrombosis and myocardial infarction: the role of bioresorbable scaffolds

Coronary atherosclerosis is a leading cause of death as a result of coronary thrombosis and acute myocardial infarction. Drug-eluting stents (DES) have dramatically improved the treatment of coronary artery stenosis. However, stent thrombosis (ST) and in-stent-restenosis (ISR) have remained a vexing limitation of the DES. After DES implantation, despite taking dual antiplatelet (DAPT) therapy, very late ST results in myocardial infarction and death. This occurs regardless of the type of polymer or antiproliferative agent used in the contemporary DES. Such adverse events occur at a rate of approximately 2% to 3% per year after the first year, which have been attributed to strut fractures, loss of vessel compliance, and neoatherosclerosis. Bioresorbable scaffolds (BRS) have been introduced to overcome the above shortfalls and to a “leave nothing behind” approach. While BRS are novel and interesting, the initial experience with BRS was hampered by the increased rate of thrombosis compared with DES. Accordingly, in this review, we summarized underlying mechanisms leading to BRS failure and provided insights into optimizing BRS deployment with intravascular imaging. In addition, we outlined the perspectives of new generations of BRS with thinner struts and new designs as well as alternative materials to improve outcomes

Pretreatment With Intracoronary Enalaprilat Protects Human Myocardium During Percutaneous Coronary Angioplasty

ObjectivesWe tested the hypothesis that enalaprilat induces preconditioning (PC)-mimetic actions in patients with stable coronary artery disease.BackgroundAngiotensin-converting enzyme (ACE) inhibitors increase the bioavailability of bradykinin, which induces cardiac PC.MethodsTwenty-two patients undergoing coronary angioplasty were randomized to an intracoronary infusion of enalaprilat or placebo, followed 10 min later by a PC protocol.ResultsIn control patients, the ST-segment shift was greater during the first inflation than during the second and third inflations, both on the intracoronary electrocardiogram (ECG) (21.0 ± 2.8 mm vs. 13.0 ± 2.0 mm and 13.0 ± 2.0 mm, p < 0.05) and the surface ECG (16.0 ± 4.0 mm vs. 10.0 ± 2.0 mm and 9.0 ± 2.0 mm, p < 0.05). In contrast, enalaprilat-pretreated patients showed no change in ST-segment shift during inflations on either the intracoronary or the surface ECG. During the first inflation, the ST-segment shift was significantly smaller in treated versus control patients. The chest pain score during the first inflation was also significantly smaller in treated patients versus control patients (33.0 ± 6.0 mm vs. 64.0 ± 6.0 mm) and did not change in treated patients during the second and third inflations, whereas it decreased significantly in control patients. In a subset of 6 patients, enalaprilat increased coronary blood flow during infusion, but this effect dissipated before the beginning of angioplasty.ConclusionsPretreatment with enalaprilat attenuates the manifestations of myocardial ischemia during angioplasty. This is the first in vivo evidence showing that an ACE inhibitor protects human myocardium, possibly via PC-mimetics actions, a novel property that might explain the cardioprotective actions of these drugs