Clonal hematopoiesis is associated with cardiovascular events in patients with stable coronary artery disease

Clonal hematopoiesis (CH) is a risk factor for atherosclerotic cardiovascular disease, but the impact of smaller clones and the effect on inflammatory parameters is largely unknown. Using ultrasensitive single-molecule molecular inversion probe sequencing, we evaluated the association between CH and a first major adverse cardiovascular event (MACE) in patients with angiographically documented stable coronary artery disease (CAD) and no history of acute ischemic events. CH was associated with an increased rate of MACE at four years follow-up. The size of the clone predicted MACE at an optimal cut-off value of 1.07% variant allele frequency (VAF). Mutation carriers had no change in monocytes subsets or cytokine production capacity but had higher levels of circulating tissue factor, matrilysin, and proteinase-activated receptor-1. Our study identified CH driver mutations with a VAF as small as 1.07% as a residual cardiovascular risk factor and identified potential biomarkers and therapeutic targets for patients with stable CAD.

Intermediate monocytes are associated with the first major adverse cardiovascular event in patients with stable coronary artery disease

BACKGROUND

Traditional risk stratification modestly predicts adverse cardiovascular events in patients with coronary artery disease (CAD). Our aim was to investigate the association between monocyte subsets numbers and function, and the first major adverse cardiovascular event (MACE) in patients with symptomatic stable CAD and angiographically documented coronary atherosclerosis.

METHODS

Patients with stable CAD were screened for inclusion. Using flow cytometry, we identified classical, intermediate, and non-classical monocyte subsets and we assessed cytokine production capacity after ex-vivo stimulation of peripheral blood mononuclear cells. Clinical follow-up was performed after four years. The endpoint was the composite of cardiovascular death, acute myocardial infarction, and ischemic stroke.

RESULTS

A cohort of 229 patients was recruited. The percentage of intermediate monocytes was positively associated with adverse cardiovascular events at follow-up (HR 1.09; 95%CI 1.02-1.16; p = 0.006), while the percentage of classical monocytes was identified as a protective factor for adverse outcomes (HR 0.96; 95%CI 0.94-0.99; p = 0.02). The percentage of intermediate monocytes remained independently associated with outcomes after adjusting for age, systolic blood pressure, and left ventricular ejection fraction (HR 1.07; 95% CI 1.01-1.14; p = 0.04). Several correlations were identified between monocyte subsets and stimulated cytokine production, but cytokine production capacity was not associated with adverse outcomes.

CONCLUSIONS

In patients with stable CAD, intermediate monocytes were associated with MACE at follow-up. The association was not due to an increased cytokine production capacity. Novel biomarkers could improve risk stratification in patients with stable CAD and could represent new pharmacological targets against atherosclerosis progression.

Fractional flow reserve and instantaneous wave-free ratio in coronary artery bypass grafting: a meta-analysis and practice review

Objective

Fractional flow reserve (FFR) and instantaneous wave-free ratio (iFR) are invasive methods to assess the functional significance of intermediate severity coronary lesions. Both indexes have been extensively validated in clinical trials in guiding revascularisation in patients with stable ischaemic heart disease undergoing percutaneous coronary intervention (PCI) with improved clinical outcomes. However, the role of these tools in coronary artery bypass grafting (CABG) is less clear.

Methods

A meta-analysis of randomised trials and observational studies was carried out to help in determining the optimal strategy for assessing lesion severity and selecting graft targets in patients undergoing CABG. Electronic searches were carried out on Embase, MEDLINE, and Web of Science. A group of four authors independently screened and then assessed the retrieved records. Cochrane's Risk of Bias and Robins-I tools were used for bias assessment. A survey was conducted among surgeons and cardiologists to describe current attitudes towards the preoperative use of functional coronary investigations in practice.

Results

Clinical outcomes including mortality at 30 days, perioperative myocardial infarction, number of grafts, incidence of stroke, rate of further need for revascularisation, and patient-reported quality of life did not differ in CABG guided by functional testing from those guided by traditional angiography.The survey revealed that in half of the surgical and cardiology units functional assessment is performed in CABG patients; there is a general perception that functional testing has improved patient care and its use would clarify the role of moderate coronary lesions that often need multidisciplinary rediscussions; moderate stenosis are felt to be clinically relevant; and anatomical considerations need to be taken into account together with functional assessment.

Conclusions

At present, the evidence to support the routine use of functional testing in intermediate lesions for planning CABG is currently insufficient. The pooled data currently available do not show an increased risk in mortality, myocardial injury, and stroke in the FFR/iFR-guided group. Further trials with highly selected populations are needed to clarify the best strategy.

Systematic Review Registration

ClinicalTrials.gov, identifier (CRD42023414604).

CCTA-based CABG SYNTAX Score: a tool to evaluate completeness of coronary segment revascularization after bypass surgery

To describe the updated coronary computed tomographic angiography (CCTA)-based coronary artery bypass graft (CABG) anatomic SYNTAX Score (aSS) and assess its utility and reproducibility for assessing the completeness of revascularization after CABG. The CCTA-CABG aSS is a visual assessment using CCTA post-CABG which quantifies the failure in effectively grafting stenotic coronary segments, and therefore assesses the completeness of surgical revascularization. It is calculated by subtracting the aSS of successfully anastomosed coronary segments from the aSS of the native coronary tree. The inter-observer reproducibility of the CCTA-CABG aSS was evaluated in 45 consecutive patients with three-vessel disease with or without left main disease who underwent a CCTA 30 days (± 7 days) after CABG. The CCTA-CABG aSS was evaluated in 45 consecutive patients with 117 bypass grafts and 152 anastomoses. The median native coronary aSS was 35.0 [interquartile range (IQR) 27.0-41.0], whilst the median CCTA-CABG aSS was 13.0 (IQR 9.0-20.5). The inter-observer level of agreement for the native coronary aSS and the CCTA-CABG aSS were both substantial with respective Kappas of 0.67 and 0.61. The CCTA-CABG aSS was feasible in all patients who underwent CABG for complex coronary artery disease with substantial inter-observer reproducibility, and therefore can be used to quantify the completeness of revascularization after CABG.

Effects of Fractional Flow Reserve on Coronary Artery Bypass Graft Flow to Left Anterior Descending Artery

BACKGROUND

The relationships between preoperative fractional flow reserve (FFR) values of the left anterior descending artery (LAD), FFRLAD, and intraoperative transit time flow measurement (TTFM) variables in coronary artery bypass grafting (CABG) remain unclear.Methods and Results: We retrospectively collected data for 74 in situ left internal thoracic artery (LITA) grafts and 27 saphenous vein grafts (SVGs) to the LAD that were shown to be patent on postoperative angiography. Spearman correlation coefficients were determined between FFRLADand TTFM parameters of the LITA graft, as follows: maximum flow (Qmax), -0.22 (P=0.077); minimum flow (Qmin), -0.40 (P=0.014); mean flow (Qm), -0.35 (P=0.039); pulsatility index (PI), 0.33 (P=0.008); diastolic filling (DF): 0.01 (P=0.83); and systolic reverse flow (SRF), 0.37 (P=0.002). Spearman correlation coefficients between FFRLADand TTFM parameters of the SVG to LAD were: Qmax, -0.65 (P=0.004); Qmin, -0.43 (P=0.044); Qm, -0.75 (P=0.001); PI, 0.53 (P=0.033); DF, 0.14 (P=0.48); and SRF, 0.61 (P=0.009).

CONCLUSIONS

Both LITA grafts and SVGs to the LAD show negative correlations for FFRLADwith Qminand Qm, but positive correlations for FFRLADwith PI and SFR. These relationships between FFRLADand TTFM variables of CABG grafts to the LAD should be recognized.

Impact of quantitative flow ratio on graft function in patients undergoing coronary artery bypass grafting

Recent studies showed that preoperative functional assessment with fractional flow reserve (FFR) could predict a long-term patency of arterial bypass grafts in patients with coronary artery bypass grafting (CABG). Quantitative flow ratio (QFR) is a novel angiography-based approach to estimate FFR. This study aimed to investigate whether preoperative QFR could discriminate arterial bypass function at 1 year after surgery. The PRIDE-METAL registry was a prospective, multicenter observational study that enrolled 54 patients with multivessel coronary artery disease. By protocol, left coronary stenoses were revascularized by CABG with arterial grafts, whereas right coronary stenoses were treated with coronary stenting. Follow-up angiography at 1 year after surgery was scheduled to assess arterial graft patency. QFR was performed using index angiography by certified analysts, blinded to bypass graft function. The primary end point of this sub-study was the discriminative ability of QFR for arterial graft function, as assessed by receiver-operating characteristic curve. Among 54 patients enrolled in the PRIDE-METAL registry, index and follow-up angiography was available in 41 patients with 97 anastomoses. QFR were analyzed in 35 patients (71 anastomoses) with an analyzability of 85.5% (71/83). Five bypass grafts were found to be non-functional at 1 year. The diagnostic performance of QFR was substantial (area under the curve: 0.89; 95% confidence interval: 0.83 to 0.96) with an optimal cutoff of 0.76 to predict functionality of bypass grafts. Preoperative QFR is highly discriminative for predicting postoperative arterial graft function.Trial registration: Clinical.gov reference: NCT02894255.

Instantaneous wave free ratio value impact on left internal mammary artery graft patency

OBJECTIVES

To assess whether instantaneous wave - free ratio (iFR) value is associated with left internal mammary artery (LIMA) graft failure at 12 months follow-up post coronary artery bypass graft (CABG).

BACKGROUND

Data suggests bypass to a non-significant left anterior descending artery (LAD) lesion due to visual over-estimation may lead to LIMA graft failure. Implementing iFR may result in better arterial graft patency.

METHODS

In iCABG (iFR guided CABG) study patients planned to undergo an isolated CABG procedure was prospectively enrolled and iFR was performed for LAD. Coronary computed tomography angiography was performed at 2 and 12 months follow-up. The primary endpoint of this study was to determine the rate of LIMA graft occlusion or hypoperfusion at 2 and 12-months follow-up. We considered a composite secondary endpoint of Major adverse cardiovascular and cerebrovascular event (MACCE) as a secondary outcome.

RESULTS

In total 69 patients were included with no differences regarding age, sex and risk factors. At 2 months, 50 of LIMAs with pre-CABG iFR median 0.855 (0.785 - 0.892) were patent. Hypoperfusion was found in 8 LIMAs (median iFR 0.88 (0.842 - 0.90)). While, 7 LIMAs (median iFR 0.91 (0.88 - 0.96)) were occluded (p = 0.04). At 12 months, when iFR of LAD was >0.85: just 12 (31.6% out of all patent LIMAS) grafts were patent and 24 (100.0% out of all hypoperfused/occluded) grafts were hypoperfused or occluded (p < 0.001). In terms of MACCE, no difference (p = 1.0) was found between all 3 groups divided according to iFR value.

CONCLUSIONS

Instantaneous wave - free ratio value above 0.85 in LAD is a powerful tool predicting LIMA graft failure at 1-year follow up period.

Applied coronary physiology for planning and guidance of percutaneous coronary interventions. A clinical consensus statement from the European Association of Percutaneous Cardiovascular Interventions (EAPCI) of the European Society of Cardiology

The clinical value of fractional flow reserve and non-hyperaemic pressure ratios are well established in determining an indication for percutaneous coronary intervention (PCI) in patients with coronary artery disease (CAD). In addition, over the last 5 years we have witnessed a shift towards the use of physiology to enhance procedural planning, assess post-PCI functional results, and guide PCI optimisation. In this regard, clinical studies have reported compelling data supporting the use of longitudinal vessel analysis, obtained with pressure guidewire pullbacks, to better understand how obstructive CAD contributes to myocardial ischaemia, to establish the likelihood of functionally successful PCI, to identify the presence and location of residual flow-limiting stenoses and to predict long-term outcomes. The introduction of new functional coronary angiography tools, which merge angiographic information with fluid dynamic equations to deliver information equivalent to intracoronary pressure measurements, are now available and potentially also applicable to these endeavours. Furthermore, the ability of longitudinal vessel analysis to predict the functional results of stenting has played an integral role in the evolving field of simulated PCI. Nevertheless, it is important to have an awareness of the value and challenges of physiology-guided PCI in specific clinical and anatomical contexts. The main aim of this European Association of Percutaneous Cardiovascular Interventions clinical consensus statement is to offer up-to-date evidence and expert opinion on the use of applied coronary physiology for procedural PCI planning, disease pattern recognition and post-PCI optimisation.

Evaluating the Arteriotomy Size of a New Sutureless Coronary Anastomosis Using a Finite Volume Approach

OBJECTIVES

The ELANA® Heart Bypass creates a standardized sutureless anastomosis. Hereby, we investigate the influence of arteriotomy and graft size on coronary hemodynamics.

METHODS

A computational fluid dynamics (CFD) model was developed. Arteriotomy size (standard 1.43 mm2; varied 0.94 - 3.6 mm2) and graft diameter (standard 2.5 mm; varied 1.5 - 5.0 mm) were independent parameters. Outcome parameters were coronary pressure and flow, and fractional flow reserve (FFR).

RESULTS

The current size ELANA (arteriotomy 1.43 mm2) presented an estimated FFR 0.65 (39 mL/min). Enlarging arteriotomy increased FFR, coronary pressure, and flow. All reached a maximum once the arteriotomy (2.80 mm2) surpassed the coronary cross-sectional area (2.69 mm2, i.e. 1.85 mm diameter), presenting an estimated FFR 0.75 (46 mL/min). Increasing graft diameter was positively related to FFR, coronary pressure, and flow.

CONCLUSION

The ratio between the required minimal coronary diameter for application and the ELANA arteriotomy size effectuates a pressure drop that could be clinically relevant. Additional research and eventual lengthening of the anastomosis is advised.

Pathophysiology and management of saphenous vein graft disease

INTRODUCTION

The saphenous vein graft (SVG) is the most used conduit in CABG. With standardization of its use as a conduit came an understanding of its accelerated atherosclerosis, known as saphenous vein graft disease (SVGD). Given its extensive use, a review of the pathophysiology and management of SVGD is important as we optimize its use.

AREAS COVERED

For this review, an extensive literature search was completed to identify and examine the evolution of SVG in CABG, mechanisms driving SVGD, and methods developed to prevent and manage it. This includes a review of relevant major papers and trials in this space.

EXPERT OPINION

Eras of evolution in SVG usage in CABG include an experimental era, era of SVG dominance in CABG, and the current era of mixed venous and arterial grafting. As SVGD was studied, the mechanisms behind it became more understood, and prevention and management methods were developed. As advances in surgical techniques and pharmacotherapy continue to reduce occurrence and severity of SVGD, long-term patency of SV grafts continues to improve and remain excellent in optimized settings. With continued innovation and improvement in operative techniques, the SVG conduit is and will remain an important player in the field of coronary bypass.

Impact of Functional vs Anatomic Complete Revascularization in Coronary Artery Bypass Grafting

BACKGROUND

This study was conducted to evaluate the impact of functional and anatomic complete revascularization on long-term clinical outcomes after coronary artery bypass grafting (CABG).

METHODS

Of 2034 patients who underwent primary isolated CABG between 2006 and 2017, 1162 patients who underwent off-pump CABG for 3-vessel disease and for whom data on functional and anatomic completeness of revascularization were available on the basis of preoperative myocardial single photon emission computed tomography and early postoperative graft angiography were enrolled. The median follow-up duration was 82.4 months (interquartile range, 50.8-122.4 months). Univariate and multivariate analyses were performed to evaluate the impact of the functional and anatomic completeness of revascularization on long-term survival.

RESULTS

Of 1162 patients, anatomic complete revascularization was achieved in 1014 patients (87.3%), whereas functional complete revascularization was achieved in 1077 patients (92.7%). Early mortality occurred in 7 patients. Late death occurred in 322 of 1155 early survivors. The 5- and 10-year overall survival rates were 84.3% and 66.7%, respectively. Univariate analyses demonstrated that functional completeness of revascularization was a statistically significant risk factor (P = .038), whereas anatomic completeness was not (P = .859). The multivariate analysis showed that functional completeness of revascularization (hazard ratio, 1.54; 95% CI, 1.08-2.22; P = .019) and age, underweight status, diabetes mellitus, chronic kidney disease, chronic obstructive pulmonary disease, and left ventricular dysfunction were significant factors associated with long-term survival.

CONCLUSIONS

Functional rather than anatomic completeness of revascularization has a significant impact on the long-term survival in patients who undergo CABG.

Quantitative flow ratio-guided versus angiography-guided operation for valve disease accompanying coronary heart disease

Background

Valve replacement combined with coronary artery bypass graft (CABG) operation (VR + CABG) is usually associated with higher mortality and complication rates. Currently, angiography remains the most commonly used approach to guide CABG. The aim of this study is to investigate whether a quantitative flow ratio (QFR)-guided strategy can improve the clinical outcomes of VR + CABG.

Methods

Patients (n = 536) treated by VR + CABG between January 2018 and December 2021 were retrospectively assessed. In 116 patients, all lesions were revascularized entirely based on QFR (the QFR-guided group), whereas in 420 patients, all lesions were revascularized entirely based on angiography (the angiography-guided group). To minimize selection bias between the 2 groups, propensity score matching was performed at a ratio of 1:2. The primary endpoint of the study was the rate of major adverse cardiac and cerebrovascular events (MACCE) at 1-year, which was defined as a composite of cardiac mortality, myocardial infarction (MI), any repeat revascularization, and stroke.

Results

No statistically significant differences were observed in the baseline clinical characteristics between the QFR-guided and angiography-guided groups after propensity score matching. The mean age of all patients was 66.2 years [standard deviation (SD) = 8.3], 370 (69%) were men, the mean body-mass index of the population was 24.8 kg/m² (SD = 4.5), 129 (24%) had diabetes, and 229 (43%) had angina symptoms. When compared with the angiography-guided group, the QFR-guided group had a significantly shorter operative time (323 ± 60 min vs. 343 ± 71 min, P = 0.010), extra corporal circulation time (137 ± 38 min vs. 155 ± 62 min, P = 0.004), clamp time (73 ± 19 min vs. 81 ± 18 min, P < 0.001), and less intraoperative bleeding volume (640 ± 148 ml vs. 682 ± 166 ml, P = 0.022). Compared with the angiography-guided group, the 1-year MACCE was significantly lower in the QFR-guided group (6.9% vs. 14.7%, P = 0.036, hazard ratio = 0.455, 95% confidence interval: 0.211-0.982).

Conclusion

Our results raise the hypothesis that among patients who undergo VR + CABG, QFR-guided strategy is associated with optimized surgical procedure and a superior clinical outcome, as evidenced by a lower rate of MACCE at 1-year compared with conventional angiography-guided strategy.

Fractional Flow Reserve versus Angiography-Guided Management of Coronary Artery Disease: A Meta-Analysis of Contemporary Randomised Controlled Trials

Background and Aims: Randomised controlled trials (RCTs) comparing outcomes after fractional flow reserve (FFR)-guided versus angiography-guided management for obstructive coronary artery disease (CAD) have produced conflicting results. We investigated the efficacy and safety of an FFR-guided versus angiography-guided management strategy among patients with obstructive CAD. Methods: A systematic electronic search of the major databases was performed from inception to September 2022. We included studies of patients presenting with angina or myocardial infarction (MI), managed with medications, percutaneous coronary intervention, or bypass graft surgery. A meta-analysis was performed by pooling the risk ratio (RR) using a random-effects model. The endpoints of interest were all-cause mortality, MI and unplanned revascularisation. Results: Eight RCTs, with outcome data from 5077 patients, were included. The weighted mean follow up was 22 months. When FFR-guided management was compared to angiography-guided management, there was no difference in all-cause mortality [3.5% vs. 3.7%, RR: 0.99 (95% confidence interval (CI) 0.62−1.60), p = 0.98, heterogeneity (I2) 43%], MI [5.3% vs. 5.9%, RR: 0.93 (95%CI 0.66−1.32), p = 0.69, I2 42%], or unplanned revascularisation [7.4% vs. 7.9%, RR: 0.92 (95%CI 0.76−1.11), p = 0.37, I2 0%]. However, the number patients undergoing planned revascularisation by either stent or surgery was significantly lower with an FFR-guided strategy [weighted mean difference: 14 (95% CI 3 to 25)%, p =< 0.001]. Conclusion: In patients with obstructive CAD, an FFR-guided management strategy did not impact on all-cause mortality, MI and unplanned revascularisation, when compared to an angiography-guided management strategy, but led to up to a quarter less patients needing revascularisation.

How to deal with nonsevere stenoses in coronary artery bypass grafting - a critical perspective on competitive flow and surgical precision

PURPOSE OF REVIEW

For invasive treatment of coronary artery disease (CAD), we assess anatomical complexity, analyse surgical risk and make heart-team decisions for percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG). With PCI, treating flow-relevant lesions is recommended, and reintervention easily treats disease progression. For CABG, some stenoses may only be borderline or nonsevere despite a clear surgical indication. As reoperations are not easy, the question on how to address these lesions has been around from the start, but has never satisfactorily been answered.

RECENT FINDINGS

With a new mechanistic perspective, we had suggested that infarct-prevention by surgical collateralization is the main prognostic mechanism of CABG in chronic coronary syndrome. Importantly, the majority of infarctions arise from nonsevere coronary lesions. Thus, surgical collateralization may be a valid treatment option for nonsevere lesions, but graft patency moves more into focus here, because graft patency directly correlates with the severity of coronary stenoses. In addition, CABG may even accelerate native disease progression.

SUMMARY

We here review the evidence for and against grafting nonsevere CAD lesions, suggesting that patency of grafts (to moderate lesions) may be improved by increasing surgical precision. In addition, we must improve our ability to predict future myocardial infarctions.

Coronary physiology in the catheterisation laboratory: an A to Z practical guide

Coronary revascularisation, either percutaneous or surgical, aims to improve coronary flow and relieve myocardial ischaemia. The decision-making process in patients with coronary artery disease (CAD) remains largely based on invasive coronary angiography (ICA), even though until recently ICA could not assess the functional significance of coronary artery stenoses. Invasive wire-based approaches for physiological evaluations were developed to properly assess the ischaemic relevance of epicardial CAD. Fractional flow reserve (FFR) and later, instantaneous wave-free ratio (iFR), were shown to improve clinical outcomes in several patient subsets when used for coronary revascularisation guidance or deferral and for procedural optimisation of percutaneous coronary intervention (PCI) results. Despite accumulating evidence and positive guideline recommendations, the adoption of invasive physiology has remained quite low, mainly due to technical and economic issues as well as to operator-resistance to change. Coronary image-based computational physiology has been recently developed, with promising results in terms of accuracy and a reduction in computational time, costs, radiation exposure and risks for the patient. Lastly, the integration of intracoronary imaging and physiology allows for individualised PCI treatment, aiming at complete relief of ischaemia through optimised morpho-functional immediate procedural results. Instead of a conventional state-of-the-art review, this A to Z dictionary attempts to provide a practical guide for the application of coronary physiology in the catheterisation laboratory, exploring several methods, their pitfalls, and useful tips and tricks.

Contemporary prevalence of coronary artery disease in patients referred for heart valve surgery

BACKGROUND

Patients undergoing heart valve surgery are routinely evaluated for the presence of coronary artery disease (CAD). Currently, concomitant valve intervention and surgical revascularization is recommended when there is obstructive CAD. The aim of our study was to evaluate the prevalence of CAD, its treatment strategies, and their prognostic implications in a contemporary population of patients with valvular heart disease (VHD) referred for valve surgery (HVS).

METHODS

In a multicenter registry, consecutive patients with formal indication for HVS referred for a preoperative routine invasive coronary angiogram (ICA) were analyzed. Baseline characteristics, CAD prevalence and revascularization patterns, as well as their impact on short and mid-term all-cause mortality, were assessed.

RESULTS

Overall, 1133 patients were included; most had aortic stenosis (69%) and obstructive CAD was present in 307 (27.1%). HVS was ultimately performed in 82.3%. In patients with CAD, 53.4% were revascularized. After a mean follow-up time of 29.06±18.46 months, all-cause mortality rate was 12.9%. In multivariate analysis, not having HVS (HR 6.845, 95% CI=4.281-10.947, P<0.001), obstructive CAD (HR 2.762, 95% CI=1.764-4.326, P<0.01), COPD (HR 2.043, 95% CI=1.014-4.197, P=0.022), and age (HR 1.030, 95% CI=1.009-1.063, P=0.047), were independent predictors of all-cause mortality. In patients with obstructive CAD who underwent HVS, revascularization was not significantly associated with survival (HR 2.127, 95% CI=0.0-4.494, P=0.048; log rank P=0.042).

CONCLUSIONS

In a contemporary cohort of patients with VHD and surgical indication, overall obstructive CAD prevalence was 27%. CAD presence and severity were associated with higher mortality. However, revascularization was not associated with a survival benefit, except in patients with left anterior descending artery disease.

Immediate impact of coronary artery bypass graft surgery on regional myocardial perfusion: Results from the Collaborative Pilot Study to Determine the Correlation Between Intraoperative Observations Using Spy Near-Infrared Imaging and Cardiac Catheterization Laboratory Physiological Assessment of Lesion Severity

Objectives

Coronary artery bypass grafting (CABG) is performed using anatomic guidance. Data connecting the physiologic significance of the coronary vessel stenosis to the acute physiologic response to grafting are lacking. The Collaborative Pilot Study to Determine the Correlation Between Intraoperative Observations Using Spy Near-Infrared Imaging and Cardiac Catheterization Laboratory Physiological Assessment of Lesion Severity study is the first to compare preintervention coronary physiology with the acute regional myocardial perfusion change (RMP-QC) at CABG in a per-graft analysis.

Methods

Non-emergent patients undergoing diagnostic catheterization suitable for multivessel CABG were enrolled. Synergy between Percutaneous Coronary Intervention with Taxus score, fractional flow reserve (FFR), instantaneous wave free ratio (iFR), and quantitative coronary angiography was documented in 75 epicardial coronary arteries, with 62 angiographically intermediate and 13 severe stenoses. At CABG, near-infrared fluorescence analysis quantified the relative change (post- vs pregrafting, termed RMP-QC) in the grafted vessel's perfusion territory. Scatter plots were constructed for RMP-QC versus quantitative coronary angiography and RMP-QC versus FFR/iFR. Exact quadrant randomization test for randomness was used.

Results

There was no relationship between RMP-QC and quantitative coronary angiography percent diameter stenosis, whether all study vessels were included (P = .949) or vessels with core-lab quantitative coronary angiography only (P = .922). A significant nonrandom association between RMP-QC and FFR (P = .025), as well as between RMP-QC and iFR (P = .008), was documented. These associations remained when excluding vessels with assigned FFR and iFR values (P = .0092 and P = .0006 for FFR and iFR, respectively).

Conclusions

The Collaborative Pilot Study to Determine the Correlation Between Intraoperative Observations Using Spy Near-Infrared Imaging and Cardiac Catheterization Laboratory Physiological Assessment of Lesion Severity study demonstrates there is no association between angiographic coronary stenosis severity and the acute perfusion change after grafting; there is an association between functional stenosis severity and absolute increase in regional myocardial perfusion after CABG.

Relation of quantitative flow ratio with transit time coronary artery bypass graft flow measurement

Background

Quantitative flow ratio (QFR) is a new functional index to assess the functional significance of coronary stenosis. While whether there is an association between QFR and transit-time flow measurement (TTFM) parameters of the target coronary artery has not been well addressed.

Methods

A total of 89 patients receiving the in situ left internal thoracic artery (LITA) grafts to the left anterior descending artery (LAD), and 19 patients undergoing the saphenous vein grafts (SVG) were enrolled in this retrospective study. The QFR value of the LAD was evaluated preoperatively. According to the QFR values, patients with the LITA to the LAD bypass grafts were divided into two groups (group A1: QFR < 0.75, group A2: QFR ≥ 0.75), and SVG patients were divided into two groups (V1 group: QFR < 0.75, V2 group: QFR ≥ 0.75).

Results

In groups A1 and A2, respectively, median graft flow (Qm) was 44 (34) mL/minute and 26.5 (30.0) ml/minute; median pulsatility index (PI) was 2.00 (1.00) and 2.65 (0.90). Significant differences were observed in Qm (P = 0.034) and PI (P = 0.030). And the correlation coefficients of the TTFM variables with QFR were Qm: r = r = −0.226, (P = 0.036), PI: r = 0.265 (P = 0.012) among the LITA to LAD population.

Conclusion

TTFM variables, especially the PI, of the LITA in situ graft to the LAD during Coronary artery bypass grafting (CABG) are strongly affected by preoperative QFR values. Moreover, in functionally mild coronary stenosis, the chance of competitive flow increases.

Quantitative flow ratio to predict long-term coronary artery bypass graft patency in patients with left main coronary artery disease

Purpose

Fractional flow reserve (FFR) has been demonstrated in some studies to predict long-term coronary artery bypass graft (CABG) patency. Quantitative flow ratio (QFR) is an emerging technology which may predict FFR. In this study, we hypothesised that QFR would predict long-term CABG patency and that QFR would offer superior diagnostic performance to quantitative coronary angiography (QCA) and intravascular ultrasound (IVUS).

Methods

A prospective study was performed on patients with left main coronary artery disease who were undergoing CABG. QFR, QCA and IVUS assessment was performed. Follow-up computed tomography coronary angiography and invasive coronary angiography was undertaken to assess graft patency.

Results

A total of 22 patients, comprising of 65 vessels were included in the analysis. At a median follow-up of 3.6 years post CABG (interquartile range, 2.3 to 4.8 years), 12 grafts (18.4%) were occluded. QFR was not statistically significantly higher in occluded grafts (0.81 ± 0.19 vs. 0.69 ± 0.21; P = 0.08). QFR demonstrated a discriminatory power to predict graft occlusion (area under the receiver operating characteristic curve, 0.70; 95% confidence interval [CI], 0.52 to 0.88; P = 0.03). At long-term follow-up, the risk of graft occlusion was higher in vessels with a QFR > 0.80 (58.6% vs. 17.0%; hazard ratio, 3.89; 95% CI, 1.05 to 14.42; P = 0.03 by log-rank test). QCA (minimum lumen diameter, lesion length, diameter stenosis) and IVUS (minimum lumen area, minimum lumen diameter, diameter stenosis) parameters were not predictive of long-term graft patency.

Conclusions

QFR may predict long-term graft patency in patients undergoing CABG.

Clinical use of physiological lesion assessment using pressure guidewires: an expert consensus document of the Japanese association of cardiovascular intervention and therapeutics-update 2022

Fractional flow reserve and instantaneous wave-free ratio are widely accepted and recommended in Western and Japanese guidelines for appropriate percutaneous coronary intervention. There are, however, many differences in clinical situations between Japan and Western countries. Therefore, the Task Force on coronary physiology of the Japanese Association of Cardiovascular Intervention and Therapeutics (CVIT) has proposed an expert consensus document to summarize current evidence and suggest the practical use of physiological lesion assessment in Japan.

Contemporary Management of Stable Coronary Artery Disease

Coronary artery disease (CAD) continues to be the leading cause of mortality and morbidity in developed countries. Assessment of pre-test probability (PTP) based on patient's characteristics, gender and symptoms, help to identify more accurate patient's clinical likelihood of coronary artery disease. Consequently, non-invasive imaging tests are performed more appropriately to rule in or rule out CAD rather than invasive coronary angiography (ICA). Coronary computed tomography angiography (CCTA) is the first-line non-invasive imaging technique in patients with suspected CAD and could be used to plan and guide coronary intervention. Invasive coronary angiography remains the gold-standard method for the identification and characterization of coronary artery stenosis. However, it is recommended in patients where the imaging tests are non-conclusive, and the clinical likelihood is very high, remembering that in clinical practice, approximately 30 to 70% of patients with symptoms and/or signs of ischemia, referred to coronary angiography, have non obstructive coronary artery disease (INOCA). In this contest, physiology and imaging-guided revascularization represent the cornerstone of contemporary management of chronic coronary syndromes (CCS) patients allowing us to focus specifically on ischemia-inducing stenoses. Finally, we also discuss contemporary medical therapeutic approach for secondary prevention. The aim of this review is to provide an updated diagnostic and therapeutic approach for the management of patients with stable coronary artery disease.

Fractional Flow Reserve-Guided PCI as Compared with Coronary Bypass Surgery

BACKGROUND

Patients with three-vessel coronary artery disease have been found to have better outcomes with coronary-artery bypass grafting (CABG) than with percutaneous coronary intervention (PCI), but studies in which PCI is guided by measurement of fractional flow reserve (FFR) have been lacking.

METHODS

In this multicenter, international, noninferiority trial, patients with three-vessel coronary artery disease were randomly assigned to undergo CABG or FFR-guided PCI with current-generation zotarolimus-eluting stents. The primary end point was the occurrence within 1 year of a major adverse cardiac or cerebrovascular event, defined as death from any cause, myocardial infarction, stroke, or repeat revascularization. Noninferiority of FFR-guided PCI to CABG was prespecified as an upper boundary of less than 1.65 for the 95% confidence interval of the hazard ratio. Secondary end points included a composite of death, myocardial infarction, or stroke; safety was also assessed.

RESULTS

A total of 1500 patients underwent randomization at 48 centers. Patients assigned to undergo PCI received a mean (±SD) of 3.7±1.9 stents, and those assigned to undergo CABG received 3.4±1.0 distal anastomoses. The 1-year incidence of the composite primary end point was 10.6% among patients randomly assigned to undergo FFR-guided PCI and 6.9% among those assigned to undergo CABG (hazard ratio, 1.5; 95% confidence interval [CI], 1.1 to 2.2), findings that were not consistent with noninferiority of FFR-guided PCI (P = 0.35 for noninferiority). The incidence of death, myocardial infarction, or stroke was 7.3% in the FFR-guided PCI group and 5.2% in the CABG group (hazard ratio, 1.4; 95% CI, 0.9 to 2.1). The incidences of major bleeding, arrhythmia, and acute kidney injury were higher in the CABG group than in the FFR-guided PCI group.

CONCLUSIONS

In patients with three-vessel coronary artery disease, FFR-guided PCI was not found to be noninferior to CABG with respect to the incidence of a composite of death, myocardial infarction, stroke, or repeat revascularization at 1 year. (Funded by Medtronic and Abbott Vascular; FAME 3 ClinicalTrials.gov number, NCT02100722.).

2021 ACC/AHA/SCAI Guideline for Coronary Artery Revascularization: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The guideline for coronary artery revascularization replaces the 2011 coronary artery bypass graft surgery and the 2011 and 2015 percutaneous coronary intervention guidelines, providing a patient-centric approach to guide clinicians in the treatment of patients with significant coronary artery disease undergoing coronary revascularization as well as the supporting documentation to encourage their use.

METHODS

A comprehensive literature search was conducted from May 2019 to September 2019, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Collaboration, CINHL Complete, and other relevant databases. Additional relevant studies, published through May 2021, were also considered. Structure: Coronary artery disease remains a leading cause of morbidity and mortality globally. Coronary revascularization is an important therapeutic option when managing patients with coronary artery disease. The 2021 coronary artery revascularization guideline provides recommendations based on contemporary evidence for the treatment of these patients. The recommendations present an evidence-based approach to managing patients with coronary artery disease who are being considered for coronary revascularization, with the intent to improve quality of care and align with patients' interests.

2021 ACC/AHA/SCAI Guideline for Coronary Artery Revascularization: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The guideline for coronary artery revascularization replaces the 2011 coronary artery bypass graft surgery and the 2011 and 2015 percutaneous coronary intervention guidelines, providing a patient-centric approach to guide clinicians in the treatment of patients with significant coronary artery disease undergoing coronary revascularization as well as the supporting documentation to encourage their use.

METHODS

A comprehensive literature search was conducted from May 2019 to September 2019, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Collaboration, CINHL Complete, and other relevant databases. Additional relevant studies, published through May 2021, were also considered.

STRUCTURE

Coronary artery disease remains a leading cause of morbidity and mortality globally. Coronary revascularization is an important therapeutic option when managing patients with coronary artery disease. The 2021 coronary artery revascularization guideline provides recommendations based on contemporary evidence for the treatment of these patients. The recommendations present an evidence-based approach to managing patients with coronary artery disease who are being considered for coronary revascularization, with the intent to improve quality of care and align with patients' interests.

Enxerto de Bypass de Artéria Coronária Guiado por Angiografia ou Fisiologia: Uma Metanálise

Fundamento:

Enquanto a angiografia coronária invasiva é considerada padrão outro para o diagnóstico da doença arterial coronariana (DAC), envolvendo os vasos coronários epicárdicos, a revascularização coronariana guiada por fisiologia representa uma prática padrão ouro contemporânea para a administração invasiva de pacientes com DAC intermediária. Porém, os resultados de longo prazo da avaliação da gravidade da estenose por meio da fisiologia, em comparação à angiografia como guia para a cirurgia de bypass – enxerto de bypass de artéria coronária (CABG), ainda são incertos. Esta metanálise visa avaliar os resultados clínicos de um CABG guiado por fisiologia em comparação a um CABG guiado pela angiografia.

Objetivos:

Buscamos determinar se os resultados entre um CABG guiado por fisiologia e os de um CABG guiado por angiografia são diferentes entre si.

Métodos:

Pesquisamos nas bases Medline, EMBASE e Cochrane Library. A última data de busca foi junho de 2020, e todos os estudos anteriores foram incluídos. Realizamos uma metanálise de razão de risco agrupado para quatro principais resultados: morte por todas as causas, infarto do miocárdio (IM), revascularização do vaso alvo (TVR) e eventos cardiovasculares adversos maiores (MACE). Valor de p <0,05 foi considerado estatisticamente significante. A heterogeneidade foi avaliada com o teste Q de Cochran, e quantificada pelo índice I2.

Resultados:

Identificamos cinco estudos incluindo um total de 1.114 pacientes. Uma metanálise agrupada não demonstrou diferenças significativas entre a estratégia da fisiologia e da angiografia para IM (razão de risco [RR] = 0,72; IC95%, 0,39–1,33; I2 = 0%; p = 0,65), TVR (RR = 1,25; IC95% = 0,73–2,13; I2 = 0%; p = 0,52), ou MACE (RR = 0,81; IC95% = 0,62–1,07; I2 = 0%; p = 1). A estratégia da fisiologia apresentou 0,63 vezes o risco de morte por todas as causas em comparação à estratégia da angiografia (RR = 0,63; IC95% = 0,42–0,96; I2 = 0%; p = 0,55).

Conclusão:

Esta metanálise demonstrou uma redução nas mortes por todas as causas quando usada a estratégia do CABG guiado por fisiologia. Porém, o curto período de acompanhamento, o tamanho da amostra pequeno dos estudos incluídos e a não-discriminação das causas de morte podem justificar essas conclusões. Estudos com períodos mais longos de acompanhamento são necessários para tirar conclusões mais robustas e definitivas.

What does complete revascularization mean in 2021? - Definitions, implications, and biases

PURPOSE OF REVIEW

Coronary revascularization is known to be an excellent treatment for coronary artery disease. However, whether incomplete myocardial revascularization compromises long-term outcomes, as compared to complete revascularization (CR), remains contentious. Herein, we review the concept of and evidence on CR/incomplete revascularization (ICR) and discuss future perspectives.

RECENT FINDINGS

When possible, achieving CR in coronary artery bypass grafting is desirable; nonetheless, ICR is also a reasonable option to balance the therapeutic benefits against the risks.

SUMMARY

Although angiography-based assessment currently remains the standard of care, fractional flow reserve guidance may reduce the number of lesions requiring revascularization, which may be helpful for an appropriate surgical revascularization strategy. In particular, utilizing this approach may refine hybrid revascularization procedures, especially among high-risk patients.

Influence of fractional flow reserve on grafts patency: Systematic review and patient-level meta-analysis

OBJECTIVE

To investigate the impact of invasive functional guidance for coronary artery bypass graft surgery (CABG) on graft failure.

BACKGROUND

Data on the impact of fractional flow reserve (FFR) in guiding CABG are still limited.

METHODS

Systematic review and individual patient data meta-analysis were performed. Primary objective was the risk of graft failure, stratified by FFR. Risk estimates are reported as odds ratios (ORs) derived from the aggregated data using random-effects models. Individual patient data were analyzed using mixed effect model to assess relationship between FFR and graft failure. This meta-analysis is registered in PROSPERO (CRD42020180444).

RESULTS

Four prospective studies comprising 503 patients referred for CABG, with 1471 coronaries, assessed by FFR were included. Graft status was available for 1039 conduits at median of 12.0 [IQR 6.6; 12.0] months. Risk of graft failure was higher in vessels with preserved FFR (OR 5.74, 95% CI 1.71-19.29). Every 0.10 FFR units decrease in the coronaries was associated with 56% risk reduction of graft failure (OR 0.44, 95% CI 0.34 to 0.59). FFR cut-off to predict graft failure was 0.79.

CONCLUSION

Surgical grafting of coronaries with functionally nonsignificant stenoses was associated with higher risk of graft failure.

Improving Terminology to Describe Coronary Artery Procedures: JACC Review Topic of the Week

Coronary artery disease (CAD) is treated with medical therapy with or without percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG). The latter 2 options are commonly referred to as "myocardial revascularization" procedures. We reason that this term is inappropriate because it is suggestive of a single treatment effect of PCI and CABG (ie, the reestablishment of blood flow to ischemic myocardium) and obscures key mechanisms, such as the improvement in coronary flow capability in the absence of ongoing ischemia, the reperfusion in the presence of ischemia, and the prevention of myocardial infarction from CAD progression. We review the current evidence on the topic and suggest the use of a purely descriptive terminology ("invasive treatment by PCI or CABG") which has the potential to improve clinical decision making and guide future trial design.

Fractional flow reserve guided versus angiographic guided surgical revascularization: A meta-analysis

BACKGROUND

Clinical benefits of FFR (Fraction Flow Reserve) driven CABG (Coronary Artery Bypass Graft) remain to be established.

METHODS

All randomized controlled trials (RCTs) and observational studies with multivariable adjustement were included. MACE (Major Adverse Cardiac Events) was the primary end point, while its single components (death, myocardial infarction, and total vessel revascularization [TVR]) along with number of anastomoses, on pump procedures and graft occlusion at angiographic follow-up were the secondary ones. Each analysis was stratified for RCTs versus observational studies.

RESULTS

Four studies (two RCTs and two observational) were included, enrolling 983 patients, 542 angio-guided and 441 FFR-guided. Mean age was 68.45 years, 79% male, with a mean EuroSCORE I of 2.7. Coronary lesions were located in 37% of patients in the left anterior descending artery, 32% in the circumflex artery, and 26% in the right coronary artery. After a mean follow-up of 40 months, risk of MACE did not differ (OR 0.86 [0.63-1.18]) as that of all cause death (OR 0.86 [0.59-1.25]), MI (OR 0.57 [0.30-1.11]) and TVR (OR 1.10 [0.65-1.85]). FFR-driven CABG reduced on-pump procedures (OR 0.58 [0.35-0.93]) and number of anastomoses (-0.40 [-0.80: -0.01]) while incidence of graft occlusion at follow-up did not differ (OR 0.59 [0.30-1.15], all CI 95%).

CONCLUSION

Fraction flow reserve driven CABG reduced the number of anastomoses and of on-pump procedures without increasing risk of MACE and without reducing graft occlusion at angiographic follow-up. ID CRD42020211945.

Percutaneous Coronary Revascularization: JACC Historical Breakthroughs in Perspective

Over the last 4 decades, percutaneous coronary intervention has evolved dramatically and is now an acceptable treatment option for patients with advanced coronary artery disease. However, trialists have struggled to establish the respective roles for percutaneous coronary intervention and coronary artery bypass graft surgery, especially in patients with multivessel disease and unprotected left-main stem coronary artery disease. Several pivotal trials and meta-analyses comparing these 2 revascularization strategies have enabled the relative merits of each technique to be established with regard to the type of ischemic syndrome, the coronary anatomy, and the patient's overall comorbidity. Precision medicine with individualized prognosis is emerging as an important method of selecting treatment. However, the never-ending advancement of technology, in conjunction with the emergence of novel pharmacological agents, will in the future continue to force us to reconsider the evolving question: "Which treatment strategy is better and for which patient?"

Health-Related Quality of Life and Angina in Fractional Flow Reserve- Versus Angiography-Guided Coronary Artery Bypass Grafting: FARGO Trial (Fractional Flow Reserve Versus Angiography Randomization for Graft Optimization)

BACKGROUND

In coronary artery bypass grafting (CABG), the use of fractional flow reserve (FFR) is insufficiently investigated. Stenosis assessment usually relies on visual estimates of lesion severity. This study evaluated health-related quality of life (HRQoL) and angina after FFR- versus angiography-guided CABG.

METHODS

One hundred patients referred for CABG were randomized to FFR- or angiography-guided CABG. In the FFR group, lesions with FFR>0.80 were deferred, while the surgeon was blinded to the FFR values in the angiography group. Before and 6 months after CABG, HRQoL was assessed by the health state classifier EQ-5D of the EuroQoL 5-level instrument and angina status based on the Canadian Cardiovascular Society classification system were registered.

RESULTS

Six-month angiography included FFR evaluations of deferred lesions. In total, completed EQ-5D of the EuroQoL 5-level instrument questionnaires were available in 86 patients (43 in the FFR versus 43 in the angiography-guided group). HRQoL was significantly improved and angina significantly decreased from baseline to 6 months after CABG with no difference between the randomization groups. Graft failure rates and clinical outcomes were similar in both groups. Patients with graft failure or FFR<0.80 of the previous deferred lesions had significantly lower visual analogue scale scores (78.7±14.2 versus 86.8±14.7, P=0.004) and more angina compared with patients without graft failure or FFR≥0.80 at 6-month follow-up.

CONCLUSIONS

FFR- versus angiography-guided CABG demonstrated similar improvements in HRQoL and angina 6 months after CABG. Graft failure or low FFR in deferred lesions were associated with low HRQoL and angina. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02477371.

Changes in surgical revascularization strategy after fractional flow reserve

AIMS

In the randomized GRAFFITI trial, surgeons drew their strategy based on coronary angiography. When patients were randomized to fractional flow reserve (FFR)-guidance, surgeons were informed of the FFR values and asked to redraw their strategy. The aim of this study was to investigate the changes induced by FFR knowledge.

METHODS AND RESULTS

The intended and performed strategy (before and after FFR) were compared. Among 172 patients, 84 with 300 lesions were randomized to the FFR-guided group. The intended strategy was to bypass 236 stenoses:108 with a venous and 128 with an arterial graft. After disclosing FFR, a change in strategy occurred in 64 lesions (21.3%) of 48 (55%) patients. Among 64 lesions for which the intended strategy was medical therapy, 16 (25%) were bypassed after disclosing FFR. The number of procedures with >1 venous graft planned was significantly reduced from 37 to 27 patients (p = .031). The proportion of on-pump surgery was significantly reduced from 71 to 61 patients (p = .006). The rates of clinical events at 1 year were similar between patients with or without at least one change in strategy.

DISCUSSION

FFR-guided CABG is associated with a simplified surgical procedure in 55% of the patients, with similar clinical outcomes.

A new way to use transit-time flow measurement for coronary artery bypass grafting

OBJECTIVES

Transit-time flow measurement is a recognized method for graft evaluation in coronary surgery. However, single flow measurement has been associated with a low specificity for detecting graft dysfunction. The goal of this study was to assess the value of transit-time flow measurement for assessing in situ internal mammary artery grafts during non-existent native coronary circulation and the relevance of collateral blood flow in target vessels.

METHODS

Between 2014 and 2018, a total of 134 patients undergoing on-pump coronary artery bypass grafting were evaluated using transit-time flow measurement. We analysed 111 single left internal mammary artery and 57 single right internal mammary artery bypasses. Correlations between coronary relevant parameters were calculated using Spearman's ρ coefficient. Risk factors for decreased flow with an arrested heart (FAH) <30 ml/min and an increased pulsatility index (PI) >3.0 as well as flow reduction >30% were calculated.

RESULTS

FAH correlated with the diameter of the target vessel (Spearman's ρ = 0.32; P < 0.001), the amount of blood distribution (Spearman's ρ = 0.34; P < 0.001), the PI (Spearman's ρ = 0.19; P = 0.019) and the degree of stenosis (Spearman's ρ = -0.17; P = 0.042). The percentage of flow change was found to correlate with the PI (Spearman's ρ = -0.47; P < 0.0001), the degree of stenosis (Spearman's ρ = 0.42; P < 0.001), the diameter of the target vessel (Spearman's ρ = -0.22; P = 0.008) and the area of blood distribution (Spearman's ρ = -0.19; P = 0.018). A small blood distribution area was the only risk factor for decreased FAH [odds ratio (OR) 8.43, confidence interval (CI) 95% (3.04-23.41); P < 0.001]. Binary logistic regression identified PI [OR 2.05, CI 95% (1.36-3.10); P = 0.001], FAH [OR 0.98, CI 95% (0.97-0.99); P = 0.005] and degree of stenosis [OR 0.95, CI 95% (0.92-0.99); P = 0.011] as risk factors for decreased flow after cardiopulmonary bypass (<30 ml/min). An increased PI (>3) was mainly influenced by percentage of flow change [OR 0.99, CI 95% (0.98-1.00); P = 0.031].

CONCLUSIONS

FAH and percentage of flow change are related to the dimensions of the target vessel and the degree of stenosis. The addition of flow measurements with the heart arrested provides additional information about the bypass graft, the quality of the anastomosis and the physiology of the coronary circulation.

Relation between functional coronary artery stenosis and graft occlusion after coronary artery bypass grafting

OBJECTIVES

This study was conducted to evaluate graft patency rates during the 5 years after coronary artery bypass grafting according to the functional significance of the coronary artery stenosis, as determined by myocardial single-photon-emission computed tomography.

METHODS

Two hundred ninety-five patients who underwent coronary artery bypass grafting using Y-composite grafts based on the in situ left internal thoracic artery, and in whom preoperative stress/rest myocardial single-photon-emission computed tomography and 1-year angiographies were available were enrolled. Seven hundred sixty-nine and 262 distal anastomoses were constructed to ischemic and nonischemic areas, respectively. One-year and 5-year angiographic occlusion rates were evaluated in all and 80.3% of study patients, respectively. Factors associated with graft occlusion were evaluated using generalized linear mixed-effects models.

RESULTS

Overall 1- and 5-year graft occlusion rates were 4.3% (44 of 1031 distal anastomoses) and 5.5% (45 out of 820), respectively. The occlusion rates of grafts bypassed to vessels with functionally significant and insignificant stenosis were 2.7% (21 out of 769) and 8.8% (23 out of 262) at 1 year and were 4.0% (25 out of 618) and 9.9% (20 out of 202) at 5 years, respectively. Graft occlusion during the 5 years after coronary artery bypass grafting was associated with the functional significance of coronary artery stenosis (odds ratio, 0.50; 95% confidence interval, 0.28-0.92). The odds ratio of the graft occlusion according to functional ischemia was lower and significant in grafts to arteries with intermediate stenosis (stenosis ≥70% but <90%; odds ratio, 0.34; 95% confidence interval, 0.13-0.93) whereas it was higher and insignificant in grafts to arteries with severe stenosis (≥90% stenosis; odds ratio, 0.76; 95% confidence interval, 0.33-1.72).

CONCLUSIONS

Graft occlusion during the 5 years after coronary artery bypass grafting was associated with the functional significance of coronary artery stenosis, particularly when the stenosis degree was not severe.

Invasive coronary physiology: a Dutch tradition

Invasive coronary physiology has been applied since the early days of percutaneous transluminal coronary angioplasty, and has become a rapidly emerging field of research. Many physiology indices have been developed, tested in clinical studies, and are now applied in daily clinical practice. Recent clinical practice guidelines further support the use of advanced invasive physiology methods to optimise the diagnosis and treatment of patients with acute and chronic coronary syndromes. This article provides a succinct review of the history of invasive coronary physiology, the basic concepts of currently available physiological parameters, and will particularly highlight the Dutch contribution to this field of invasive coronary physiology.

FFR-guided versus coronary angiogram-guided CABG: A review and meta-analysis of prospective randomized controlled trials

BACKGROUND

Fractional flow reserve (FFR) is a well-established method for the evaluation of coronary artery stenosis before percutaneous coronary intervention. However, whether FFR assessment should be routinely used before coronary artery bypass graft surgery (CABG) remains unclear. A meta-analysis of prospectively randomized controlled trials (PRCTs) was carried out to compare the outcomes of FFR-guided CABG vs coronary angiography (CAG)-guided CABG.

METHOD

The meta-analysis adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Two PRCTs (the FARGO and GRAFFITI trials) were found and included reporting data on 269 patients with 6 and 12 month follow-up. Primary endpoints were rates of overall death, MACCE, target vessel revascularization, and spontaneous myocardial infarction (MI). Secondary endpoints were overall graft patency and patency of arterial and venous grafts.

RESULTS

There were no significant differences between the FFR-guided and CAG-guided groups in the rates of overall death, MACCE, target vessel revascularization, spontaneous MI and graft patency. Meta-analysis of FARGO and GRAFFITI PRCTs showed that FFR-guided CABG and CAG-guided CABG produced similar clinical outcomes with similar graft patency rates up to a year postoperatively.

CONCLUSION

Currently available PRCTs showes no sufficient evidence to support the use FFR in CABG.

Transcatheter aortic valve replacement and percutaneous coronary intervention versus surgical aortic valve replacement and coronary artery bypass grafting in patients with severe aortic stenosis and concomitant coronary artery disease: A systematic review and meta-analysis

OBJECTIVES

We performed a systematic review and meta-analysis to evaluate the early and midterm outcomes of patients who underwent surgical aortic valve replacement (SAVR) and coronary artery bypass grafting (CABG) against patients who had transcatheter aortic valve replacement (TAVR) and percutaneous coronary intervention (PCI).

BACKGROUND

Contemporary guidelines suggest that surgical or percutaneous revascularization of significant coronary artery disease (CAD) in patients with severe aortic stenosis (AS) is a reasonable strategy.

METHODS

We conducted a comprehensive search of Medline and Embase to identify studies comparing a percutaneous transcatheter versus a surgical approach. Random effects meta-analyses using the Mantel-Haenszel method were performed to estimate the effect of percutaneous compared surgical strategies using aggregate data.

RESULTS

Six studies reporting on 1770 participants were included in the meta-analysis. There were no significant differences in effect estimates for early and midterm mortality (OR: 0.78; 95% CI, 0.50-1.20 and OR: 1.09; 95% CI, 0.80-1.49, respectively) or myocardial infarction (OR: 0.52; 95% CI, 0.20-1.33 and OR: 1.34; 95% CI, 0.67-2.65, respectively). No significant difference was shown for peri-procedural stroke (OR: 0.80; 95% CI, 0.35-1.87). A transcatheter approach had a higher rate of major vascular complications (OR: 14.44; 95% CI, 4.42-47.16), but a lower rate of acute kidney injury (OR: 0.41; 95% CI, 0.19-0.91).

CONCLUSION

Our analysis suggests that a percutaneous transcatheter approach confers similar outcomes compared to a surgical approach in patients with severe AS and CAD. However, our findings are based on low quality studies and should serve as hypothesis generating. In the absence of adequately powered studies yielding high level evidence, individualized decision making should be based on surgical risk assessment.

Fractional Flow Reserve-Based Coronary Artery Bypass Surgery: Current Evidence and Future Directions

Fractional flow reserve (FFR) provides an objective measurement of the severity of ischemia caused by coronary stenoses in downstream myocardial regions. Data from the interventional cardiology realm have suggested benefits of a FFR-guided percutaneous coronary intervention (PCI) strategy. Limited evidence is available on the use of FFR to guide coronary artery bypass grafting (CABG). The most recent data have shown that FFR might simplify CABG procedures and optimize patency of arterial grafts without any clear impact on clinical outcomes. The aim of this review was to summarize the available data on FFR-based CABG and discuss the rationale and potential consequences of a switch toward FFR-based surgical revascularization strategy.