Search

View large Download slide View large Download slide Aims Continuous thermodilution is a novel technique to quantify absolute coronary flow and microvascular resistance (MVR). Notably, intracoronary infusion of saline elicits maximal hyperaemia, obviating the need for adenosine. The primary aim of this study was to validate continuous thermodilution in humans by comparing invasive measurements to [15O]H2O positron emission tomography (PET). As a secondary goal, absolute flow and MVR were compared between invasive measurements obtained with and without adenosine. Methods and results Twenty-five patients underwent coronary computed tomography angiography (CCTA), [15O]H2O PET, and invasive assessment. Absolute coronary flow and MVR were measured in the left anterior descending and left circumflex artery using a dedicated infusion catheter and a temperature/pressure sensor-tipped guidewire. Invasive measurements were performed with and without adenosine. In order to compare invasive flow measurements with PET perfusion, subtending myocardial mass of the investigated vessels was derived from CCTA using the Voronoi algorithm. Invasive and non-invasive measurements of adenosine-induced hyperaemic flow and MVR showed strong correlation (r  = 0.91; P  < 0.001 for flow and r  = 0.85; P  < 0.001 for MVR) and good agreement [intraclass correlation coefficient (ICC) = 0.90; P  < 0.001 for flow and ICC = 0.79; P  < 0.001 for MVR]. Absolute flow and MVR also correlated well between measurements with and without adenosine (r  = 0.97; P  < 0.001 for flow and r  = 0.98; P  < 0.001 for MVR) and showed good agreement (ICC = 0.96; P  < 0.001 for flow and ICC = 0.98; P  < 0.001 for MVR). Conclusions Continuous thermodilution is an accurate method to measure absolute coronary flow and MVR, which is evidenced by strong agreement with [15O]H2O PET derived flow and resistance. Absolute flow and MVR correlate highly between invasive measurements obtained with and without adenosine, which confirms that intracoronary infusion of room temperature saline elicits steady-state maximal hyperaemia. [ABSTRACT FROM AUTHOR]

Aims To assess the effect of fractional flow reserve (FFR)-guided percutaneous coronary intervention (PCI) with contemporary drug-eluting stents on the composite of cardiac death or myocardial infarction (MI) vs. medical therapy in patients with stable coronary lesions. Methods and results We performed a systematic review and meta-analysis of individual patient data (IPD) of the three available randomized trials of contemporary FFR-guided PCI vs. medical therapy for patients with stable coronary lesions: FAME 2 (NCT01132495), DANAMI-3-PRIMULTI (NCT01960933), and Compare-Acute (NCT01399736). FAME 2 enrolled patients with stable coronary artery disease (CAD), while the other two focused on non-culprit lesions in stabilized patients after acute coronary syndrome. A total of 2400 subjects were recruited from 54 sites world-wide with 1056 randomly assigned to FFR-guided PCI and 1344 to medical therapy. The pre-specified primary outcome was a composite of cardiac death or MI. We included data from extended follow-ups for FAME 2 (up to 5.5 years follow-up) and DANAMI-3-PRIMULTI (up to 4.7 years follow-up). After a median follow-up of 35 months (interquartile range 12–60 months), a reduction in the composite of cardiac death or MI was observed with FFR-guided PCI as compared with medical therapy (hazard ratio 0.72, 95% confidence interval 0.54–0.96; P  = 0.02). The difference between groups was driven by MI. Conclusion In this IPD meta-analysis of the three available randomized controlled trials to date, FFR-guided PCI resulted in a reduction of the composite of cardiac death or MI compared with medical therapy, which was driven by a decreased risk of MI. [ABSTRACT FROM AUTHOR]

Aims: Fractional flow reserve (FFR) has proven to its prognostic and therapeutic value. However, the additive prognostic value of coronary flow reserve (CFR) remains unclear. This study sought to investigate the clinical utility of combined FFR and CFR measurements to predict outcomes. Methods and results: Using the prospective, multicentre Interventional Cardiology Research Incooperation Society-FFR registry, a total of 2088 lesions from 1837 patients were included in this substudy. Based on baseline and hyperaemic pressure gradients, we computed physiologic limits of CFR [the so called pressure-bounded (pb) CFR] and classified lesions as low (<2) or high (≥2). The primary endpoint was major adverse cardiac events (MACE, a composite of cardiac death, myocardial infarction, and revascularization) analysed on a per-patient basis. During a median follow-up of 1.9 years (interquartile range: 1.0-3.0 years), MACE occurred in 5.7% of patients with FFR ≤0.80 vs. 2.8% of patients with FFR >0.80 [adjusted hazard ratio (aHR): 2.15, 95% confidence interval (CI): 1.19-3.89; P = 0.011. In contrast, the incidence of MACE did not differ between patients with pb-CFR< 2 vs. pb-CFR ≥ 2 (4.2% vs. 4.2%; aHR: 0.98, CI: 0.60 to 1.58; P= 0.92). Incorporation of FFR significantly improved model prediction of MACE (global χ² 38.8-48.1, P = 0.002). However, pb-CFR demonstrated no incremental utility to classify outcomes (global χ² 48.1-48.2, P> 0.99). Conclusions: In this large, prospective registry of over 2000 coronary lesions, FFR was strongly associated with clinical outcomes. In contrast, a significant association between pb-CFR and clinical events could not be determined and adding knowledge of pb-CFR did not improve prognostication over FFR alone. [ABSTRACT FROM AUTHOR]

Aims The aim of this study was to investigate the physiologic parameters: fractional flow reserve (FFR), hyperaemic trans-stent gradient (HTG), and wall shear stress (WSS) at implantation and at 6-month follow-up in the drug-eluting sirolimus stent and in its bare metal counterpart implanted in pairs within the same patient. [ABSTRACT FROM PUBLISHER]