Fractional Flow Reserve-Guided Complete Revascularization Improves the Prognosis in Patients With ST-Segment-Elevation Myocardial Infarction and Severe Nonculprit Disease: A DANAMI 3-PRIMULTI Substudy (Primary PCI in Patients With ST-Elevation Myocardial Infarction and Multivessel Disease: Treatment of Culprit Lesion Only or Complete Revascularization)

Meta-Analysis of Physiology-Guided Complete or Culprit Lesion-Only Percutaneous Coronary Interventions in Myocardial Infarction

Whether physiology-guided complete revascularization of nonculprit lesions is superior to culprit lesion-only percutaneous coronary intervention (PCI) in patients with myocardial infarction (MI) and multivessel disease remains debated. Online databases were searched for randomized controlled trials comparing physiology-guided complete revascularization and culprit lesion-only PCI in patients with MI. The outcomes of interest were all-cause death, cardiovascular (CV) death, repeat revascularization, MI, stent thrombosis, and contrast-associated nephropathy/acute kidney injury. Pooled odds ratios, along with 95% confidence intervals (CI) were calculated. A total of 4,849 patients (n = 2,288 physiology-guided complete revascularization, n = 2,561 culprit lesion-only PCI) were included. The mean age was 66 years and 76% were men. At a mean follow-up of 2.5 years, physiology-guided complete revascularization was associated with significant reductions in CV death (odds ratio 0.72, 95% CI 0.54 to 0.97, p = 0.03) and repeat revascularizations (0.50, 95% CI 0.38 to 0.66, p <0.00001) compared with culprit lesion-only PCI. There were no differences between the 2 approaches in all-cause death (0.91, 95% CI 0.69 to 1.19, p = 0.50), MI (0.85, 95% CI 0.59 to 1.21, p = 0.36), stent thrombosis (1.24, 95% CI 0.58 to 2.69, p = 0.58), and contrast-associated nephropathy/acute kidney injury (1.07, 95% CI 0.88 to 1.31, p = 0.50). In conclusion, among patients with MI and multivessel disease, physiology-guided complete revascularization was associated with significant reductions in CV death and revascularizations compared with culprit lesion-only PCI.

FFR-Guided Complete or Culprit-Only PCI in Patients with Myocardial Infarction

BACKGROUND

The benefit of fractional flow reserve (FFR)-guided complete revascularization in patients with ST-segment elevation myocardial infarction (STEMI) and multivessel coronary artery disease remains unclear.

METHODS

In this multinational, registry-based, randomized trial, we assigned patients with STEMI or very-high-risk non-STEMI (NSTEMI) and multivessel disease who were undergoing primary percutaneous coronary intervention (PCI) of the culprit lesion to receive either FFR-guided complete revascularization of nonculprit lesions or no further revascularization. The primary outcome was a composite of death from any cause, myocardial infarction, or unplanned revascularization. The two key secondary outcomes were a composite of death from any cause or myocardial infarction and unplanned revascularization.

RESULTS

A total of 1542 patients underwent randomization, with 764 assigned to receive FFR-guided complete revascularization and 778 assigned to receive culprit-lesion-only PCI. At a median follow-up of 4.8 years (interquartile range, 4.3 to 5.2), a primary-outcome event had occurred in 145 patients (19.0%) in the complete-revascularization group and in 159 patients (20.4%) in the culprit-lesion-only group (hazard ratio, 0.93; 95% confidence interval [CI], 0.74 to 1.17; P = 0.53). With respect to the secondary outcomes, no apparent between-group differences were observed in the composite of death from any cause or myocardial infarction (hazard ratio, 1.12; 95% CI, 0.87 to 1.44) or unplanned revascularization (hazard ratio, 0.76; 95% CI, 0.56 to 1.04). There were no apparent between-group differences in safety outcomes.

CONCLUSIONS

Among patients with STEMI or very-high-risk NSTEMI and multivessel coronary artery disease, FFR-guided complete revascularization was not shown to result in a lower risk of a composite of death from any cause, myocardial infarction, or unplanned revascularization than culprit-lesion-only PCI at 4.8 years. (Funded by the Swedish Research Council and others; FULL REVASC ClinicalTrials.gov number, NCT02862119.).

Angiographic Severity of the Nonculprit Lesion and the Efficacy of Fractional Flow Reserve-Guided Complete Revascularization in Patients With AMI: FRAME-AMI Substudy

BACKGROUND

The benefit of fractional flow reserve (FFR)-guided percutaneous coronary intervention (PCI) for noninfarct-related artery (IRA) lesions with angiographically severe stenosis in patients with acute myocardial infarction is unclear.

METHODS

Among 562 patients from the FRAME-AMI trial (Fractional Flow Reserve Versus Angiography-Guided Strategy for Management of Non-Infraction Related Artery Stenosis in Patients With Acute Myocardial Infarction) who were randomly allocated into either FFR-guided or angiography-guided PCI for non-IRA lesions, the current study evaluated the relationship between non-IRA stenosis measured by quantitative coronary angiography (QCA) and the efficacy of FFR-guided PCI. The incidence of the primary end point (death, myocardial infarction, or repeat revascularization) was compared between FFR- and angiography-guided PCI according to non-IRA stenosis severity (QCA stenosis ≥70% or <70%).

RESULTS

A total of 562 patients were assigned to FFR-guided (n=284) versus angiography-guided PCI (n=278). At a median follow-up of 3.5 years, the primary end point occurred in 14 of 181 patients with FFR-guided PCI and 31 of 197 patients with angiography-guided PCI among patients with QCA stenosis ≥70% (8.5% versus 19.2%; hazard ratio, 0.41 [95% CI, 0.22-0.80]; P=0.008), while occurred in 4 of 103 patients with FFR-guided PCI and 9 of 81 patients with angiography-guided PCI among those with QCA stenosis <70% (3.9% versus 11.1%; P=0.315). There was no significant interaction between treatment strategy and non-IRA stenosis severity (P for interaction=0.636). FFR-guided PCI was associated with the reduction of death and myocardial infarction in both patients with QCA stenosis ≥70% (6.7% versus 15.1%; P=0.008) and those with QCA stenosis <70% (1.0% versus 9.6%; P=0.042) compared with angiography-guided PCI.

CONCLUSIONS

In patients with acute myocardial infarction and multivessel disease, FFR-guided PCI tended to have a lower risk of primary end point than angiography-guided PCI regardless of non-IRA stenosis severity without significant interaction.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT02715518.

Prognostic impact of fractional flow reserve measurements in patients with acute coronary syndromes: a subanalysis of the FLORIDA study

Randomized trials suggest benefits for fractional flow reserve (FFR)-guided vs. angiography-guided treatment strategies in well-defined and selected patient cohorts with acute coronary syndromes (ACS). The long-term prognostic value of FFR measurement in unselected all-comer ACS patients, however, remains unknown. This subanalysis of the Fractional FLOw Reserve In cardiovascular DiseAses (FLORIDA) study sought to investigate the long-term effects of FFR in the management of lesions in patients with acute coronary syndrome (ACS). FLORIDA was an observational all-comer cohort study performed in Germany, that was population-based and unselected. Patients enrolled into the anonymized InGef Research Database presenting with ACS and undergoing coronary angiography between January 2014 and December 2015 were included in the analysis. Patients were stratified into either the FFR-guided or the angiography-guided treatment arm, based on the treatment received. A matched cohort study design was used. The primary endpoint was all-cause mortality. The secondary endpoint was major adverse cardiovascular events (MACE), a composite of death, non-fatal myocardial infarction (MI), and repeat revascularization. Follow-up time was 3 years. Rates of 3-year mortality were 10.2 and 14.0% in the FFR-guided and the angiography-guided treatment arms (p = 0.04), corresponding to a 27% relative risk reduction for FFR in ACS patients. Rates of MACE were similar in both arms (47.7 vs. 51.5%, p = 0.14), including similar rates of non-fatal MI (27.7 vs. 25.4%, p = 0.47) and revascularization (9.9 vs. 12.1%, p = 0.17). In this large, all-comer observational study of ACS patients, FFR-guided revascularization was associated with a lower mortality at 3 years. This finding encourages the routine use of FFR to guide lesion revascularization in patients presenting with ACS.

Management of Non-Culprit Lesions in STEMI Patients with Multivessel Disease

Multivessel disease is observed in approximately 50% of patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI). Data from randomized clinical trials has shown that complete revascularization in the STEMI setting improves clinical outcomes by reducing the risk of reinfarction and urgent revascularization. However, the timing and modality of revascularization of non-culprit lesions are still debated. PCI of non-culprit lesions can be performed during the index primary PCI or as a staged procedure and can be guided by angiography, functional assessment, or intracoronary imaging. In this review, we summarize the available evidence about the management of non-culprit lesions in STEMI patients with or without cardiogenic shock.

Coronary Assessment and Revascularization Before Transcutaneous Aortic Valve Implantation: An Update on Current Knowledge

Transcutaneous aortic valve implantation (TAVI) has led to a paradigm shift in the treatment of severe aortic stenosis (AS) in the elderly and is expanding to still younger and lower-risk patients with severe AS as an alternative to surgical aortic valve replacement (SAVR). While the role of coronary artery bypass grafting with SAVR is well-documented, the analog of percutaneous coronary intervention with TAVI is less so. The aim of this review is to provide an overview of the important challenges in treating severe AS and co-existing coronary artery disease in patients planned for TAVI.

Management of Culprit and Non-Culprit Lesions in Acute Coronary Syndrome

Multivessel coronary artery disease, defined by the presence of a significant stenosis (≥50% diameter) in two or more epicardial coronary vessels, usually occurs in more than 50% of patients with ST-segment elevation myocardial infarction. The latest guidelines indicate revascularization of the non-culprit artery with a recommendation of class IIB. However, the management of non-culprit lesions in patients with acute coronary syndrome is still a matter of debate. This article presents the most recent concepts related to the management of culprit and non-culprit coronary lesions, based on advanced imaging approaches, in order to identify high-risk patients and prevent further acute coronary syndromes.

Physiology-guided revascularization versus optimal medical therapy of nonculprit lesions in elderly patients with myocardial infarction: Rationale and design of the FIRE trial

BACKGROUND

Myocardial infarction (MI) in elderly patients is associated with unfavorable prognosis, and it is becoming an increasingly prevalent condition. The prognosis of elderly patients is equally impaired in ST-segment elevation (STE) or non-STE (NSTE), and it is markedly worsened by the common presence of multivessel disease (MVD). Given the limited evidence available for elderly patients, it has not yet been established whether, as for younger patients, a complete revascularization strategy in MI patients with MVD should be advocated. We present the design of a dedicated study that will address this research gap.

METHODS AND DESIGN

The FIRE trial is a prospective, randomized, international, multicenter, open-label study with blinded adjudicated evaluation of outcomes. Patients aged 75 years and older, with MI (either STE or NSTE), MVD at coronary artery angiography, and a clear culprit lesion will be randomized to culprit-only treatment or to physiology-guided complete revascularization. The primary end point will be the patient-oriented composite end point of all-cause death, any MI, any stroke, and any revascularization at 1 year. The key secondary end point will be the composite of cardiovascular death and MI. Quality of life and physical performance will be evaluated as well. All components of the primary and key secondary outcome will be tested also at 3 and 5 years. The sample size for the study is 1,400 patients.

IMPLICATIONS

The FIRE trial will provide evidence on whether a specific revascularization strategy should be applied to elderly patients presenting MI and MVD to improve their clinical outcomes.

Complete versus incomplete coronary revascularization: definitions, assessment and outcomes

Coronary artery disease is the leading cause of morbidity and mortality worldwide. Selected patients with obstructive coronary artery disease benefit from revascularization with percutaneous coronary intervention (PCI) or coronary artery bypass graft (CABG) surgery. Many (but not all) studies have demonstrated increased survival and greater freedom from adverse cardiovascular events after complete revascularization (CR) than after incomplete revascularization (ICR) in patients with multivessel disease. However, achieving CR after PCI or CABG surgery might not be feasible owing to patient comorbidities, anatomical factors, and technical or procedural considerations. These factors also mean that comparisons between CR and ICR are subject to multiple confounders and are difficult to understand or apply to real-world clinical practice. In this Review, we summarize and critically appraise the evidence linking various types of ICR to adverse outcomes in patients with multivessel disease and stable ischaemic heart disease, non-ST-segment elevation acute coronary syndrome or ST-segment elevation myocardial infarction, with or without cardiogenic shock. In addition, we provide practical recommendations for revascularization in patients with high-risk multivessel disease to optimize their long-term clinical outcomes and identify areas requiring future clinical investigation.

Rationale and design of the MULTISTARS AMI Trial: A randomized comparison of immediate versus staged complete revascularization in patients with ST-segment elevation myocardial infarction and multivessel disease

About half of patients with acute ST-segment elevation myocardial infarction (STEMI) present with multivessel coronary artery disease (MVD). Recent evidence supports complete revascularization in these patients. However, optimal timing of non-culprit lesion revascularization in STEMI patients is unknown because dedicated randomized trials on this topic are lacking. STUDY DESIGN: The MULTISTARS AMI trial is a prospective, international, multicenter, randomized, two-arm, open-label study planning to enroll at least 840 patients. It is designed to investigate whether immediate complete revascularization is non-inferior to staged (within 19-45 days) complete revascularization in patients in stable hemodynamic conditions presenting with STEMI and MVD and undergoing primary percutaneous coronary intervention (PCI). After successful primary PCI of the culprit artery, patients are randomized in a 1:1 ratio to immediate or staged complete revascularization. The primary endpoint is a composite of all-cause death, non-fatal myocardial infarction, ischemia-driven revascularization, hospitalization for heart failure, and stroke at 1 year. CONCLUSIONS: The MULTISTARS AMI trial tests the hypothesis that immediate complete revascularization is non-inferior to staged complete revascularization in stable patients with STEMI and MVD.

Fractional flow reserve-guided PCI in patients with and without left ventricular hypertrophy: a DANAMI-3-PRIMULTI substudy

AIMS

The aim of this substudy was to investigate the correlation between fractional flow reserve (FFR) and diameter stenosis in patients with STEMI with and without left ventricular hypertrophy (LVH), and the influence of LVH on complete FFR-guided revascularisation versus culprit only, in terms of risk of clinical outcome.

METHODS AND RESULTS

In this DANAMI-3-PRIMULTI substudy, 279 patients with STEMI had cardiac magnetic resonance (CMR) imaging for assessment of left ventricular mass index. Ninety-six patients had FFR evaluation of a non-culprit lesion. Diameter stenosis of the non-culprit lesion was determined with two-dimensional quantitative coronary analysis. The diameter stenosis (56.9% vs 54.3%, p=0.38) and FFR value (0.83 vs 0.85, p=0.34) were significantly correlated in both groups (Spearman's ρ=-0.40 and -0.41 without LVH and with LVH, respectively; p<0.001) but were not different between patients without and with LVH (p for interaction=0.87). FFR-guided complete revascularisation was associated with reduced risk of death, myocardial infarction or ischaemia-driven revascularisation both for patients without LVH (HR 0.42, 95% CI: 0.20-0.85) and for patients with LVH (HR 0.50, 95% CI: 0.17-1.47), with no interaction between the FFR-guided complete revascularisation and LVH (p for interaction=0.82).

CONCLUSIONS

LVH did not interact with the correlation between diameter stenosis and FFR and did not modify the impact of complete revascularisation on the occurrence of subsequent clinical events.

The benefit of complete revascularization after primary PCI for STEMI is attenuated by increasing age: Results from the DANAMI-3-PRIMULTI randomized study

OBJECTIVES

To ascertain the effect of age on outcomes after culprit-only and complete revascularization after Primary PCI (PPCI) for ST-elevation myocardial infarction (STEMI).

BACKGROUND

The numbers of older patients being treated with PPCI are increasing. The optimal management of nonculprit stenoses in such patients is unclear.

METHODS

We conducted an analysis of patients aged ≥75 years randomized in the DANAMI-3-PRIMULTI study to either culprit-only or complete FFR-guided revascularization. The primary endpoint was a composite of all-cause mortality, nonfatal reinfarction, and ischaemia-driven revascularization of lesions in noninfarct-related arteries after a median of 27 months of follow-up.

RESULTS

One hundred and ten of six hundred and twenty seven patients in the DANAMI-3-PRIMULTI trial were aged ≥75 years. These patients were more likely female (p < .001), hypertensive (p < .001), had lower hemoglobin levels (p < .001), and higher serum creatinine levels (p < .001) than the younger patients in the trial. Other than less use of drug-eluting stents (96.6 versus 88.0%: p = .02), there were no significant differences in procedural technique and success between patients aged <75 years and those ≥75 years of age. There was no significant difference in the incidence of the primary endpoint in patients ≥75 years randomized to culprit-only or FFR-guided complete revascularization (HR 1.49 [95% CI 0.57-4.65]; log-rank p = .19; p for interaction versus patients <75 years <.001). There was a significant interaction between age as a continuous variable, treatment assignment, and the primary outcome (p < .001); beyond the age of about 75 years, there may be no prognostic advantage to complete revascularization.

CONCLUSIONS

In patients ≥75 years, after treatment of the culprit lesion in STEMI, there is no significant prognostic benefit to prophylactic complete revascularization of nonculprit stenoses. Pending further study, data would support a symptom-guided approach to further invasive treatment.

2020 Focused Update of the 2012 Guidelines of the Taiwan Society of Cardiology for the Management of ST-Segment Elevation Myocardial Infarction

One of the major missions of the Taiwan Society of Cardiology is to publish practice guidelines that are suitable for local use in Taiwan. The ultimate purpose is to continuously improve cardiovascular health care from the implementation of the recommendations in the guidelines. Despite recent improvement of medical care, patients with ST-segment elevation myocardial infarction (STEMI) still carry a high morbidity and mortality. There have been many changes in the concepts of STEMI diagnosis and treatment in recent years. The 2020 focused update of the 2012 guidelines of the Taiwan Society of Cardiology for the management of STEMI is an amendment of the 2012 guidelines based on the newest published scientific data. The recommendations in this focused update provide the diagnosis and treatment strategy for STEMI that should be generally implemented in Taiwan. Nevertheless, guidelines never completely replace clinical judgment and medical decision still should be determined individually.

Physiological Assessment of Coronary Lesions in 2020

PURPOSE OF REVIEW

Physiological assessment of coronary artery disease (CAD) is an essential component of the interventional cardiology toolbox. However, despite long-term data demonstrating improved outcomes, physiology-guided percutaneous coronary intervention (PCI) remains underutilized in current practice. This review outlines the indications and technical aspects involved in evaluating coronary stenosis physiology, focusing on the latest developments in the field.

RECENT FINDINGS

Beyond fractional flow reserve (FFR), non-hyperemic pressure ratios (NHPR) that assess coronary physiology at rest without hyperemia now abound. Additional advances in other alternative FFR approaches, including non-invasive coronary CT (FFR_CT), invasive angiography (FFR_angio), and optical coherence tomography (FFR_OCT), are being realized. Artificial intelligence algorithms and robust tools that enable detailed pre-procedure "virtual" intervention are also emerging. The benefits of coronary physiological assessment to determine lesion functional significance are well established. In addition to stable CAD, coronary physiology can be especially helpful in clinical scenarios such as left main and multivessel CAD, serial lesions, non-infarct-related arteries in acute coronary syndromes, and residual ischemia post-PCI. Today, coronary physiological assessment remains an indispensable tool in the catheterization laboratory, with an exciting technological future that will further refine clinical practice and improve patient care.

[Coronary physiology in the catheter laboratory]

The regulation of coronary flow is mainly located in the resistance vessels of the microcirculation, so that the functional relevance of a coronary stenosis arises from the interaction between the epicardial stenosis and the downstream microcirculation. These complex interactions are precisely detectable by physiological measurements, such as the instantaneous wave-free ratio (iwFR) or the fractional flow reserve (FFR). In contrast, the purely visual assessment of the coronary anatomy could lead to misinterpretation and possibly to incorrect revascularization decisions. Consequently, in the current guidelines on myocardial revascularization of the European Society of Cardiology (ESC) the measurement of iwFR and FFR has a class IA indication in intermediate stenoses with unclear hemodynamic relevance. Despite this clear recommendation, physiological measurements are not yet regularly used in the clinical routine. Besides the purely hemodynamic assessment, novel methods such as co-registration and coronary mapping can be used for virtual planning of percutaneous coronary interventions, especially in vessels with diffuse lesions and serial stenoses. Furthermore, invasive flow measurements are also helpful for risk stratification between conservative and interventional treatment of patients with acute coronary syndrome, where additional factors of flow limitation, such as coronary spasm, thrombus and acute disturbance of the microcirculation play an important role.

Multivessel percutaneous coronary intervention in patients with acute myocardial infarction and severe renal dysfunction

AIMS

The aim of this study was to compare the outcomes between multivessel and infarct-related artery (IRA)-only percutaneous coronary intervention (PCI) in patients with acute myocardial infarction (AMI), multivessel disease (MVD), and severe renal dysfunction (RD) using the nationwide AMI registry.

METHODS AND RESULTS

Among 13,104 patients, 537 diagnosed with AMI and MVD who had severe RD at presentation (estimated glomerular filtration rate [GFR] <30 mL/min/1.73 m2, mean: 19.1±7.5 mL/min/1.73 m2) and underwent PCI during index hospitalisation were selected. The patients were classified according to treatment strategy, i.e., multivessel PCI (49.0%) or IRA-only PCI. The primary endpoint was major adverse cardiac events (MACE), a composite of all-cause death, myocardial reinfarction, re-hospitalisation for heart failure, and any repeat revascularisation at one year. The safety outcome was the worsening of renal function (WRF), defined as a 30% reduction in estimated GFR from baseline to 12-month follow-up. The adjusted MACE risks were similar in groups after Cox regression (41.8% vs 39.8%, hazard ratio [HR] 1.008 [0.743-1.367]) and propensity score-matching analysis (HR 0.974 [0.651-1.377]). Multivessel PCI showed a significant tendency of higher rates of WRF (24.8% vs 11.1%, adjusted odds ratio 2.134 [0.976-4.668]).

CONCLUSIONS

Multivessel PCI was associated with similar outcomes compared to IRA-only PCI in patients with AMI, MVD, and severe RD.

2019 Canadian Cardiovascular Society/Canadian Association of Interventional Cardiology Guidelines on the Acute Management of ST-Elevation Myocardial Infarction: Focused Update on Regionalization and Reperfusion

Rapid reperfusion of the infarct-related artery is the cornerstone of therapy for the management of acute ST-elevation myocardial infarction (STEMI). Canada's geography presents unique challenges for timely delivery of reperfusion therapy for STEMI patients. The Canadian Cardiovascular Society/Canadian Association of Interventional Cardiology STEMI guideline was developed to provide advice regarding the optimal acute management of STEMI patients irrespective of where they are initially identified: in the field, at a non-percutaneous coronary intervention-capable centre or at a percutaneous coronary intervention-capable centre. We had also planned to evaluate and incorporate sex and gender considerations in the development of our recommendations. Unfortunately, inadequate enrollment of women in randomized trials, lack of publication of main outcomes stratified according to sex, and lack of inclusion of gender as a study variable in the available literature limited the feasibility of such an approach. The Grading Recommendations, Assessment, Development, and Evaluation system was used to develop specific evidence-based recommendations for the early identification of STEMI patients, practical aspects of patient transport, regional reperfusion decision-making, adjunctive prehospital interventions (oxygen, opioids, antiplatelet therapy), and procedural aspects of mechanical reperfusion (access site, thrombectomy, antithrombotic therapy, extent of revascularization). Emphasis is placed on integrating these recommendations as part of an organized regional network of STEMI care and the development of appropriate reperfusion and transportation pathways for any given region. It is anticipated that these guidelines will serve as a practical template to develop systems of care capable of providing optimal treatment for a wide range of STEMI patients.

Characterisation of lesions undergoing ischaemia-driven revascularisation after complete revascularisation versus culprit lesion only in patients with STEMI and multivessel disease: a DANAMI-3-PRIMULTI substudy

AIMS

Treatment of the infarct-related artery only (IRA only) in ST-segment elevation myocardial infarction (STEMI) is associated with a significantly higher rate of ischaemia-driven revascularisation (ID-RV) during follow-up than fractional flow reserve-guided complete revascularisation (FFR-CRV). This study aimed to characterise all lesions which underwent ID-RV in the DANAMI-3-PRIMULTI trial with respect to location, stenosis grade and functional significance.

METHODS AND RESULTS

The study included 627 patients with STEMI and multivessel disease; 313 patients were randomised to treatment of the IRA only versus 314 undergoing staged FFR-CRV during the index admission. Rates of admission for suspected cardiac ischaemia (17%) were similar in both groups; however, ID-RV was significantly less frequent in the FFR-CRV group than in the IRA-only group (5% vs. 17%; p<0.001). In both groups, the primary reason for ID-RV was related to non-culprit, non-treated lesions (N=71/82 lesions in IRA-only; N=13/26 in FFR-CRV). De novo lesions or revascularisation of previously treated lesions were rarely causes of ID-RV. In the IRA-only group, there was a trend towards a higher ID-RV rate for lesions with a higher stenosis grade and located in more proximal segments - in particular, ≥80% stenosis of the left anterior descending and right coronary artery also led to angina class IV/unstable angina. In the FFR-CRV group, an FFR value ≤0.80 was shown to be an appropriate threshold for revascularisation.

CONCLUSIONS

FFR-CRV in STEMI is associated with a significantly lower rate of ID-RV at follow-up than treatment of the IRA only. This is due to a difference in non-culprit, non-treated lesions between both groups and not in de novo lesions or repeat revascularisation of previously treated lesions. Further considerations are warranted in case of high-grade non-culprit stenosis at proximal coronary segments, borderline FFR values and/or anticipated complex PCI.

Complete Revascularization Versus Culprit Lesion Only in Patients With ST-Segment Elevation Myocardial Infarction and Multivessel Disease: A DANAMI-3-PRIMULTI Cardiac Magnetic Resonance Substudy

OBJECTIVES

The aim of this study was to evaluate the effect of fractional flow reserve (FFR)-guided revascularization compared with culprit-only percutaneous coronary intervention (PCI) in patients with ST-segment elevation myocardial infarction (STEMI) on infarct size, left ventricular (LV), function, LV remodeling, and the presence of nonculprit infarctions.

BACKGROUND

Patients with STEMI with multivessel disease might have improved clinical outcomes after complete revascularization compared with PCI of the infarct-related artery only, but the impact on infarct size, LV function, and remodeling as well as the risk for periprocedural infarction are unknown.

METHODS

In this substudy of the DANAMI-3 (Third Danish Trial in Acute Myocardial Infarction)-PRIMULTI (Primary PCI in Patients With ST-Elevation Myocardial Infarction and Multivessel Disease: Treatment of Culprit Lesion Only or Complete Revascularization) randomized trial, patients with STEMI with multivessel disease were randomized to receive either complete FFR-guided revascularization or PCI of the culprit vessel only. The patients underwent cardiac magnetic resonance imaging during index admission and at 3-month follow-up.

RESULTS

A total of 280 patients (136 patients with infarct-related and 144 with complete FFR-guided revascularization) were included. There were no differences in final infarct size (median 12% [interquartile range: 5% to 19%] vs. 11% [interquartile range: 4% to 18%]; p = 0.62), myocardial salvage index (median 0.71 [interquartile range: 0.54 to 0.89] vs. 0.66 [interquartile range: 0.55 to 0.87]; p = 0.49), LV ejection fraction (mean 58 ± 9% vs. 59 ± 9%; p = 0.39), and LV end-systolic volume remodeling (mean 7 ± 22 ml vs. 7 ± 19 ml; p = 0.63). New nonculprit infarction occurring after the nonculprit intervention was numerically more frequent among patients treated with complete revascularization (6 [4.5%] vs. 1 [0.8%]; p = 0.12).

CONCLUSIONS

Complete FFR-guided revascularization in patients with STEMI and multivessel disease did not affect final infarct size, LV function, or remodeling compared with culprit-only PCI.

International Study of Comparative Health Effectiveness with Medical and Invasive Approaches-Chronic Kidney Disease (ISCHEMIA-CKD): Rationale and design

BACKGROUND

Patients with chronic kidney disease (CKD) and stable ischemic heart disease are at markedly increased risk of cardiovascular events. Prior trials comparing a strategy of optimal medical therapy (OMT) with or without revascularization have largely excluded patients with advanced CKD. Whether a routine invasive approach when compared with a conservative strategy is beneficial in such patients is unknown.

METHODS

ISCHEMIA-CKD is a National Heart, Lung, and Blood Institute-funded randomized trial designed to determine the comparative effectiveness of an initial invasive strategy (cardiac catheterization and optimal revascularization [percutaneous coronary intervention or coronary artery bypass graft surgery, if suitable] plus OMT) versus a conservative strategy (OMT alone, with cardiac catheterization and revascularization [percutaneous coronary intervention or coronary artery bypass graft surgery, if suitable] reserved for failure of OMT) on long-term clinical outcomes in 777 patients with advanced CKD (defined as those with estimated glomerular filtration rate <30 mL/min/1.73m2 or on dialysis) and moderate or severe ischemia on stress testing. Participants were randomized in a 1:1 fashion to the invasive or a conservative strategy. The primary end point is a composite of death or nonfatal myocardial infarction. Major secondary endpoints are a composite of death, nonfatal myocardial infarction, hospitalization for unstable angina, hospitalization for heart failure, or resuscitated cardiac arrest; angina control; and disease-specific quality of life. Safety outcomes such as initiation of maintenance dialysis and a composite of initiation of maintenance dialysis or death will be reported. The trial is projected to have 80% power to detect a 22% to 24% reduction in the primary composite end point with the invasive strategy when compared with the conservative strategy.

CONCLUSIONS

ISCHEMIA-CKD will determine whether an initial invasive management strategy improves clinical outcomes when added to OMT in patients with advanced CKD and stable ischemic heart disease.

Appropriate use of noninvasive ischemia testing to guide revascularization decision making following acute ST elevation myocardial infarction in Latin American countries: Results from an expert panel meeting of the International Atomic Energy Agency

Across Latin American and Caribbean countries, cardiovascular disease and especially ischemic heart disease is currently the main cause of death both in men and in women. For most Latin American and Caribbean countries, public and community health efforts aim to define care strategies which are both clinically and cost effective and promote primary and secondary prevention, resulting in improved patient outcomes. The optimal approach to deal with acute events such as ST-elevation myocardial infarction (STEMI) is a matter of controversy; however, there is an expanding role for assessing residual ischemic burden in STEMI patients following primary percutaneous coronary intervention. Although randomized clinical trials have established the value of staged fractional flow reserve-guided revascularization, the use of noninvasive functional imaging modalities may play a similar role at a much lower cost. For LAC, available stress imaging techniques could be applied to define residual ischemia in the non-infarct related artery and to target revascularization in a staged procedure after primary percutaneous coronary intervention The use of nuclear cardiac imaging, supported by its relatively wide availability, moderate cost, and robust quantitative capabilities, may serve to guide effective care and to reduce subsequent cardiac events in patients with coronary artery disease. This noninvasive approach may avert potential safety issues with repeat and lengthy invasive procedures, and serve as a baseline for subsequent follow-up stress testing following the index STEMI event. This consensus document was devised from an expert panel meeting of the International Atomic Energy Agency, highlighting available evidence with a focus on the utility of stress myocardial perfusion imaging in post-STEMI patients. The document could serve as guidance to the prudent and appropriate use of nuclear imaging for targeting therapeutic management and avoiding unnecessary invasive procedures within Latin American and Caribbean countries, where resources could be scarce.

Pooled diagnostic accuracy of resting distal to aortic coronary pressure referenced to fractional flow reserve: The importance of resting coronary physiology

INTRODUCTION

Both resting and hyperemic physiologic methods to guide coronary revascularization improve cardiovascular outcomes compared with angiographic guidance alone. Fractional flow reserve (FFR) remains underutilized due to concerns regarding hyperemia, prompting study of resting distal to aortic coronary pressure (Pd/Pa). Pd/Pa is a vasodilator-free resting index unlike FFR. While Pd/Pa is similar to another resting index, instantaneous wave-free ratio (iFR), it is a whole-cycle measurement not limited to the wave-free diastolic period. Pd/Pa is not validated clinically although multiple accuracy studies have been performed. Our meta-analysis examines the overall diagnostic accuracy of Pd/Pa referenced to FFR, the accepted invasive standard of ischemia.

METHODS

We searched PubMed, EMBASE, Central, ProQuest, and Web of Science databases for full text articles published through August 9, 2017 addressing the diagnostic accuracy of Pd/Pa referenced to FFR < 0.80. The following keywords were used: "distal coronary artery pressure" OR "Pd/Pa" AND "fractional flow reserve" OR "FFR."

RESULTS

In total, 14 studies comprising 7004 lesions were identified. Pooled diagnostic accuracy estimates of Pd/Pa versus FFR < 0.80 were: sensitivity, 0.77 (95% CI, 0.75-0.78); specificity, 0.82 (0.81-0.83); positive likelihood ratio, 4.7 (3.3-6.6); negative likelihood ratio, 0.29 (0.24-0.34); diagnostic odds ratio, 18.1 (14.4-22.6); area under the summary receiver-operating characteristic curve of 0.88; and diagnostic accuracy of 0.80 (0.76-0.83).

CONCLUSIONS

Pd/Pa shows adequate agreement with FFR as a resting index of coronary stenosis severity without the undesired effects and cost of hyperemic agents. Pd/Pa has the potential to guide coronary revascularization with easier application and availability compared with iFR and FFR.

Complete Versus Culprit-Only Revascularization in STEMI: a Contemporary Review

PURPOSE OF REVIEW

In ST-segment elevation myocardial infarction, urgent revascularization of the culprit coronary vessel and restoration of coronary flow is the goal of the initial management. However, obstructive non-culprit disease is frequently concomitantly found during initial angiography and portends a poor prognosis. Management of non-culprit lesions in ST-segment elevation myocardial infarction (STEMI) has been the subject of extensive debate. This review will examine the currently available evidence, with a specific focus on randomized clinical trials performed to date.

RECENT FINDINGS

Although early observational data suggested better outcomes with culprit-only revascularization, more recent data from several randomized trials have suggested improved outcomes with complete multivessel revascularization, either during the index PCI procedure or as a staged procedure. Data from recent randomized controlled trials have suggested the superiority of complete or multivessel revascularization and have subsequently led to changes to the most recent iterations of STEMI guidelines. However, the optimal management and timing of revascularization of non-culprit lesions in STEMI remain controversial.

Instantaneous wave-free ratio as an alternative to fractional flow reserve in assessment of moderate coronary stenoses: A meta-analysis of diagnostic accuracy studies

BACKGROUND/PURPOSE

Fractional flow reserve (FFR) remains underutilized due to practical concerns related to the need for hyperemic agents. These concerns have prompted the study of instantaneous wave-free ratio (iFR), a vasodilator-free index of coronary stenosis. Non-inferior cardiovascular outcomes have been demonstrated in two recent randomized clinic trials. We performed this meta-analysis to provide a necessary update of the diagnostic accuracy of iFR referenced to FFR based on the addition of eight more recent studies and 3727 more lesions.

METHODS

We searched the PubMed, EMBASE, Central, ProQuest, and Web of Science databases for full text articles published through May 31, 2017 to identify studies addressing the diagnostic accuracy of iFR referenced to FFR≤0.80. The following keywords were used: "instantaneous wave-free ratio" OR "iFR" AND "fractional flow reserve" OR "FFR."

RESULTS

In total, 16 studies comprising 5756 lesions were identified. Pooled diagnostic accuracy estimates of iFR versus FFR≤0.80 were: sensitivity, 0.78 (95% CI, 0.76-0.79); specificity, 0.83 (0.81-0.84); positive likelihood ratio, 4.54 (3.85-5.35); negative likelihood ratio, 0.28 (0.24-0.32); diagnostic odds ratio, 17.38 (14.16-21.34); area under the summary receiver-operating characteristic curve, 0.87; and an overall diagnostic accuracy of 0.81 (0.78-0.84).

CONCLUSIONS

In conclusion, iFR showed excellent agreement with FFR as a resting index of coronary stenosis severity without the undesired effects and cost of hyperemic agents. When considering along with its clinical outcome data and ease of application, the diagnostic accuracy of iFR supports its use as a suitable alternative to FFR for physiology-guided revascularization of moderate coronary stenoses.

SUMMARY

We performed a meta-analysis of the diagnostic accuracy of iFR referenced to FFR. iFR showed excellent agreement with FFR as a resting index of coronary stenosis severity without the undesired effects and cost of hyperemic agents. This supports its use as a suitable alternative to FFR for physiology-guided revascularization of moderate coronary stenoses.

PET measurements of myocardial blood flow post myocardial infarction: Relationship to invasive and cardiac magnetic resonance studies and potential clinical applications

This review focuses on clinical studies concerning assessment of coronary microvascular and conduit vessel function primarily in the context of acute and sub acute myocardial infarction (MI). The ability of quantitative PET measurements of myocardial blood flow (MBF) to delineate underlying pathophysiology and assist in clinical decision making in this setting is discussed. Likewise, considered are physiological metrics fractional flow reserve, coronary flow reserve, index of microvascular resistance (FFR, CFR, IMR) obtained from invasive studies performed in the cardiac catheterization laboratory, typically at the time of PCI for MI. The role both of invasive studies and cardiac magnetic resonance (CMR) imaging in assessing microvascular function, a key determinant of prognosis, is reviewed. The interface between quantitative PET MBF measurements and underlying pathophysiology, as demonstrated both by invasive and CMR methodology, is discussed in the context of optimal interpretation of the quantitative PET MBF exam and its potential clinical applications.

Non-infarct related artery revascularization in ST-segment elevation myocardial infarction patients with multivessel disease

PURPOSE OF REVIEW

Multivessel disease (MVD) is common in ST-segment elevation myocardial infarction (STEMI) patients undergoing primary percutaneous coronary intervention (PCI) and is associated with significant risk of future cardiovascular (CV) events including short and longer-term mortality. In this review, we examine the pathophysiologic construct contributing to adverse prognosis of MVD in STEMI, relevant available evidence that currently guides the management of the noninfarct-related artery (IRA) stenosis and define the remaining knowledge gaps for future studies.

RECENT FINDINGS

Results of recent small sized randomized trials, when pooled, suggest improvement in CV outcomes including CV mortality and repeat revascularization with revascularization of the non-IRA stenosis compared with medical management alone. In addition, there does not appear to be an increase in bleeding, contrast-induced nephropathy or stroke, as suggested by earlier observational data.

SUMMARY

These recent data have led to a Class IIb recommendation in the American College of Cardiology/American Heart Association guidelines stating that non-IRA revascularization may be considered in selected patients with STEMI and MVD who are hemodynamically stable, either at the time of primary PCI or as a planned staged procedure. The ongoing COMPLETE and CULPRIT-SHOCK studies will provide additional data to further inform the role of non-IRA revascularization and its timing in the management of these patients.