Coronary Artery Plaque Phenotype and 5-Year Clinical Outcomes in Older Patients with Non-ST Elevation Acute Coronary Syndrome.

Background: Lesions with thin-cap fibroatheroma (TCFA), small luminal area and large plaque burden (PB) have been considered at high risk of cardiovascular events. Older patients were not represented in studies which demonstrated correlation between clinical outcome and plaque characteristics. This study aims to investigate the prognostic role of high-risk plaque characteristics and long-term outcome in older patients presenting with non-ST elevation acute coronary syndrome (NSTEACS). Methods: This study recruited older patients aged ≥ 75 years with NSTEACS undergoing virtual-histology intravascular ultrasound (VH-IVUS) imaging from the Improve Clinical Outcomes in high-risk patieNts with acute coronary syndrome (ICON-1). Primary endpoint was the composite of major adverse cardiovascular events (MACE) consisting of all-cause mortality, myocardial infarction (MI), and any revascularisation. Every component of MACE and target vessel failure (TVF) including MI and any revascularisation were considered as secondary endpoints. Results: Eighty-six patients with 225 vessels undergoing VH-IVUS at baseline completed 5-year clinical follow-up. Patients with minimal lumen area (MLA) ≤ 4 mm 2 demonstrated increased risk of MACE (hazard ratio [HR] 2.37, 95% confidence interval [CI] 1.00-5.59, p = 0.048) with a worse event-free survival (Log Rank 4.17, p = 0.041) than patients with MLA > 4 mm 2 . Patients with combination of TCFA, MLA ≤ 4 mm 2 and PB ≥ 70% showed high risk of MI (HR 5.23, 95% CI 1.05-25.9, p = 0.043). Lesions with MLA ≤ 4 mm 2 had 6-fold risk of TVF (HR 6.16, 95% CI 1.24-30.5, p = 0.026). Conclusions: Small luminal area appears as the major prognostic factor in older patients with NSTEACS at long-term follow-up. Combination of TCFA, MLA ≤ 4 mm 2 and PB ≥ 70% was associated with high risk of MI. Clinical Trial Registration: NCT01933581.

Management of failed stenting of the unprotected left main coronary artery.

Percutaneous coronary intervention (PCI) is increasingly accepted as treatment for unprotected left main coronary artery (ULMCA) disease especially in those patients who are unsuitable for cardiac surgery. Treatment of any stent failure is associated with increased complexity and worse clinical outcomes when compared with de novo lesion revascularization. Intracoronary imaging has provided new insight into mechanisms of stent failure and treatment options have developed considerably over the last decade. There is paucity of evidence on the management strategy for stent failure in the specific setting of ULMCA. Treating any left main with PCI requires careful consideration and consequently treatment of failed stents in ULMCA is complex and provides unique challenges. Consequently, we provide an overview of ULMCA stent failure, proposing a tailored algorithm to guide best management and decision in daily clinical practice, with a special focus on intracoronary imaging characterization of causal mechanisms and specific technical and procedural considerations.

Angiography-derived versus invasively-determined index of microcirculatory resistance in the assessment of coronary microcirculation: A systematic review and meta-analysis.

BACKGROUND: The index of microvascular resistance (IMR) is an established tool to assess the status of coronary microcirculation. However, the need for a pressure wire and hyperemic agents have limited its routine use and have led to the development of angiography-derived pressure-wire-free methods (angiography-derived IMR [IMRAngio]). In this review and meta-analysis, we aim to assess the global diagnosis accuracy of IMRAngio versus IMR. METHODS: A systematic review of the literature was performed. Studies directly evaluating IMRAngio versus IMR were considered eligible. Pooled values of diagnostic test and summary receiver operator curve were calculated. RESULTS: Seven studies directly comparing IMRAngio versus IMR were included (687 patients; 807 vessels). Pooled sensitivity, specificity, +likelihood ratio (LR), and -LR were 82%, 83%, 4.5, and 0.26 respectively. Pooled accuracy was 83% while pooled positive predictive value and negative predictive value were 76% and 85%, respectively. Comparable results were obtained when analyzing by clinical scenario (acute and nonacute coronary syndromes). CONCLUSION: IMRAngio shows a good diagnostic performance for the prediction of abnormal IMR.

Volume of contrast to creatinine clearance ratio predicts early mortality and AKI after TAVI.

The volume of contrast to creatinine clearance ratio (CV/CrCl) is a useful indicator of the risk of acute kidney injury (AKI) in patients undergoing percutaneous interventional procedures. Association between CV/CrCl and adverse outcome after transcatheter aortic valve implantation (TAVI) was suggested but it is not well established. A large retrospective multicenter cohort of 1381 patients treated with TAVI was analyzed to assess the association between CV/CrCl and the risk of AKI and mortality at 90 days and 1 year after TAVI. Patients receiving renal replacement therapy at the time of TAVI were excluded. CV/CrCl ≥ 2.2 was associated with the risk of AKI and 90 days mortality after TAVI after adjustment for age, sex, diabetes, baseline left ventricular function, baseline chronic kidney disease (CKD), previous myocardial infarction and peripheral vascular disease (hazard ratio [HR]: 1.16, 95% confidence interval [CI]: 1.09-1.22, p < 0.0001). Importantly, CV/CrCl was associated with the adverse outcome independently from the presence of baseline CKD (p for interaction = 0.22). CV/CrCl was independently associated with the individual components of the composite primary outcome including AKI (odds ratio: 1.18, 95% CI: 1.08-1.28, p < 0.0001) and 90 days mortality (HR: 1.90, 95% CI: 1.01-3.60, p = 0.047) after TAVI. AKI (HR: 1.94, 95% CI: 1.21-3.11, p = 0.006) but not CV/CrCl was associated with the risk of 1-year mortality after TAVI. CV/CrCl is associated with excess renal damage and early mortality after TAVI. Procedural strategies to minimize the CV/CrCl during TAVI may improve early clinical outcomes in patients undergoing TAVI.

Impact of physiologically diffuse versus focal pattern of coronary disease on quantitative flow reserve diagnostic accuracy.

BACKGROUND: Fractional flow reserve (FFR) and instantaneous wave-free ratio (iFR) disagree in about 20% of intermediate coronary lesions. As the physiological pattern of coronary artery disease has a significant influence on FFR-iFR discordance, we sought to assess it may impact on the diagnostic accuracy of quantitative flow reserve (QFR). METHODS: One hundred and ninety-four patients with 224 intermediate coronary lesions were investigated with iFR, FFR, and QFR. The physiological pattern of disease was assessed with iFR Scout pullback and QFR virtual pullback in all the cases. RESULTS: A predominantly physiologically focal pattern was observed in 81 (36.2%) lesions, whereas a predominantly physiologically diffuse was observed in 143 (63.8%) cases. QFR demonstrated a significant correlation (r = 0.581, p < 0.001) and a substantial agreement with iFR, both in diffuse (AUC = 0.798) and in focal (AUC = 0.812) pattern of disease. Discordance between QFR and iFR was observed in 51 (22.8%) lesions, consisting of iFR+/QFR- (64.7%) and iFR-/QFR+ (35.3%). Notably, the physiological pattern of disease was the only variable significantly associated with iFR/QFR discordance. QFR virtual pullback demonstrated an excellent agreement (83.9%) with iFR Scout pullback in classifying the physiological pattern of disease. CONCLUSIONS: QFR has a good diagnostic accuracy in assessing myocardial ischemia independently of the pattern of coronary disease. However, the physiological pattern of disease has an influence on the QFR/iFR discordance, which occurs in ~20% of the cases. The QFR virtual pullback correctly defined the physiological pattern of disease in the majority of the cases using the iFR pullback as reference.

Pressure-controlled intermittent coronary sinus occlusion improves the vasodilatory microvascular capacity and reduces myocardial injury in patients with STEMI.

BACKGROUND: Preliminary data suggest that pressure-controlled intermittent coronary sinus occlusion (PICSO) might reduce the infarct size (IS) in patients with anterior ST-elevation myocardial infarction (STEMI). However, the applicability of this therapy to patients with inferior STEMI and its exact mechanism of action is uncertain. METHODS AND RESULTS: Thirty-six patients (27 anterior and 9 inferior) with STEMI underwent PICSO-assisted-primary percutaneous intervention (PPCI) and were compared with matched controls who underwent standard PCI (n = 72). Median age was 63 (55-70) years and 82% were male. Coronary microvascular status was assessed using thermodilution-derived index of microcirculatory resistance (IMR) and the vasodilatory capacity was assessed using the resistive reserve ratio (RRR). IS and microvascular obstruction (MVO) were assessed using cardiovascular magnetic resonance imaging (CMR) within 48 h and 6 months of follow-up. At completion of PPCI, IMR improved significantly in PICSO-treated patients compared with controls in patients with either anterior (63.7 [49.8-74.6] vs. 35.9 [27.9-47.6], p < 0.001) or inferior STEMI (60.0 [47.6-67.1] vs. 22.7 [18.4-35.0], p < 0.001). RRR significantly improved after PICSO treatment for anterior (1.21 [1.01-1.42] vs. 1.73 [1.51-2.16], p = 0.002) or inferior STEMI (1.39 [1.05-1.90] vs. 2.87 [2.17-3.78], p = 0.001), whereas it did not change in controls compared with baseline. Patients treated with PICSO presented significantly less frequently with MVO (66.6% vs. 86.1%, p = 0.024) and smaller 6-month IS compared with controls (26% [17%-30%] vs. 30% [21%-37%], p = 0.045). CONCLUSION: PICSO therapy may improve microvascular function and vasodilatory capacity, which contributes to reducing IS in patients with STEMI undergoing PPCI.

Ultrasound guided vascular access site management and left ventricular pacing are associated with improved outcomes in contemporary transcatheter aortic valve replacement: Insights from the OxTAVI registry.

OBJECTIVES: To identify clinical and procedural practice predictors of avoidable complications during transcatheter aortic valve replacement (TAVR). BACKGROUND: TAVR is evolving as a viable strategy for treatment of aortic stenosis (AS). Vascular complications, major bleeding, or pericardial tamponade may be influenced by procedural practice. METHODS: The Oxford TAVR (OxTAVI) prospective registry was retrospectively analyzed to identify predictors of avoidable procedural complications in a contemporary cohort of transfemoral TAVR between January 2015 and September 2018. The primary endpoint was defined as a hierarchic composite of in-hospital mortality, pericardial effusion/cardiac tamponade, major bleeding, and vascular access complications. Individual components of the primary endpoint have been analyzed separately. RESULTS: Five-hundred-twenty-nine patients underwent transfemoral TAVR using contemporary techniques during the study period and were enrolled in the OxTAVI registry. Female sex and high frailty were associated with a higher risk of death, major bleeding, vascular complication or pericardial tamponade. The use of ultrasound (US) guidance for vascular access management was independently associated with a reduced composite primary endpoint (OR = 0.35, CI:0.14-0.86, p = .02) after adjustment for clinical confounders, largely driven by a threefold reduction in vascular access complication (OR = 0.29, CI:0.15-0.55, p < .001). Performing rapid pacing via the left ventricle guidewire (LV-GW) was associated with a significant decrease in the risk of cardiac tamponade/pericardial effusion (OR = 0.19, CI:0.05-0.66, p = .009). CONCLUSION: US-guided vascular access management and rapid pacing via the LV-GW are important determinants of reduced procedural complications during TAVR.

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.

Significant Drop in Right Atrial Pressure Does Not Influence Fractional Flow Reserve Coronary Assessment.

The effect of a highly elevated level of right atrial filling pressure on fractional flow reserve (FFR) measurement remains unclear. Transcatheter tricuspid valve intervention, a recently introduced option for inoperable or high-risk patients, represents a unique model of in-vivo physiology to investigate the eventual influence of central venous pressure on coronary FFR measurements. The case is reported of a patient with a degenerated tricuspid surgical bioprosthesis who underwent transcatheter tricuspid valve-in-valve replacement and concomitant coronary functional assessment with FFR. In an experimental model, the significant fall in right atrial pressure did not influence FFR measurements in the presence of angiographically proven mild coronary artery disease.

Intravascular lithotripsy-assisted transfemoral transcatheter aortic valve implantation after failed balloon angioplasty in patients with severe calcified peripheral artery disease.

Objectives: Calcific peripheral artery disease (PAD) is a common finding in patients scheduled for transcatheter aortic valve implantation (TAVI) and often requires iliofemoral axis preparation. However, evidence about the use of intravascular lithotripsy (IVL) in this setting is scarce. The aim of this study was to describe in-hospital and mid-term outcomes of IVL-assisted transfemoral (TF)-TAVI in patients with severe calcific PAD. Methods: The study included 13 patients with severe calcified PAD who were initially scheduled for balloon angioplasty (PTA)-assisted TF-TAVI but were eventually treated with peripheral IVL between October 2020 and February 2024. Accurate analysis of preoperative computed tomography scans revealed difficult TF access routes (severe calcified PAD with minimal lumen diameter ≤ 4.5 mm, circumferential calcification along iliofemoral axis, and marked vessels tortuosity). Results: In all cases, IVL was performed after PTA failure and allowed successful valve delivery. One patient had procedural bleeding (BARC-3a). The valve was successfully delivered without complications in 12 patients (92.3%), and no major adverse events were reported at the longest follow-up (median 18.5 months). Conclusions: IVL-assisted TF-TAVI may represent a feasible and safe option for patients presenting with severe aortic stenosis and severe calcified PAD. However, standardization of the access site severity as well as indications for a planned up-front IVL-assisted strategy are missing and require dedicated studies.

Clinical Updates in Coronary Artery Disease: A Comprehensive Review.

Despite significant goals achieved in diagnosis and treatment in recent decades, coronary artery disease (CAD) remains a high mortality entity and continues to pose substantial challenges to healthcare systems globally. After the latest guidelines, novel data have emerged and have not been yet considered for routine practice. The scope of this review is to go beyond the guidelines, providing insights into the most recent clinical updates in CAD, focusing on non-invasive diagnostic techniques, risk stratification, medical management and interventional therapies in the acute and stable scenarios. Highlighting and synthesizing the latest developments in these areas, this review aims to contribute to the understanding and management of CAD helping healthcare providers worldwide.

Outpatient tricuspid regurgitation in the community: Clinical context and outcome.

BACKGROUND AND AIMS: Epidemiology of tricuspid regurgitation (TR) is poorly known and its burden in the community is challenging to define. We aimed to evaluate the prevalence of TR in a geographically defined area and its outcome, in particular overall survival and hospitalization, considering different clinical contexts. METHODS: We retrospectively analyzed consecutive outpatients referred between 2006 and 2013 for echocardiography and clinical evaluation. Patients with at least moderate TR were included and five different clinical settings were defined: concomitant significant left-sided valvular heart disease (LVHD-TR), heart failure (HF-TR), previous open-heart valvular surgery (postop-TR), pulmonary hypertension (PHTN-TR) and isolated TR (isolated-TR). Primary endpoint was a composite outcome of all-cause mortality or first hospitalization for HF. RESULTS: Of 6797 consecutive patients with a clinical visit and echocardiograms performed in routine practice in a geographically defined community, moderate or severe TR was found in 4.8% of patients (327) . During median follow-up of 6.1 years, TR severity was a determinant of event-free survival. Analyzed for each clinical subset, eight-year event-free survival was 87 ± 7% for postop-TR subgroup, 75 ± 7% for isolated-TR, 67 ± 6% for PHTN-TR, 58 ± 6% for LHVD -TR and 52 ± 11% for HF-TR. CONCLUSION: Moderate or more TR is a notable finding in the community and has impact on event-free survival in all clinical settings, with the worst outcomes when associated with relevant left-sided valvular heart disease and HF.

Coronary microvascular dysfunction in patients undergoing transcatheter aortic valve implantation.

OBJECTIVES: This study aimed to evaluate the prognostic value of coronary microvascular dysfunction (CMD) at long term after transcatheter aortic valve implantation (TAVI) and to explore its relationship with extravalvular cardiac damage (EVCD). Moreover, we sought to test the correlation between angiography-derived index of microcirculatory resistance (IMRangio) and invasive IMR in patients with aortic stenosis (AS). METHODS: This was a retrospective analysis of the Verona Valvular Heart Disease Registry (Italy) including 250 patients (83 (80-86) years, 53% female) with severe AS who underwent TAVI between 2019 and 2021. IMRangio was calculated offline using a computational flow model applied to coronary angiography obtained during the TAVI workup. CMD was defined as IMRangio ≥30 units.The primary endpoint was the composite of cardiovascular death and rehospitalisation for heart failure (HF). Advanced EVCD was defined as pulmonary circulation impairment, severe tricuspid regurgitation or right ventricular dysfunction.The correlation between IMR and IMRangio was prospectively assessed in 31 patients undergoing TAVI. RESULTS: The primary endpoint occurred in 28 (11.2%) patients at a median follow-up of 22 (IQR 12-30) months. Patients with CMD met the primary endpoint more frequently than those without CMD (22.9% vs 2.8%, p<0.0001). Patients with CMD were more frequently characterised by advanced EVCD (33 (31.4%) vs 27 (18.6%), p=0.024). CMD was an independent predictor of adverse outcomes (adjusted HR 6.672 (2.251 to 19.778), p=0.001) and provided incremental prognostic value compared with conventional clinical and imaging variables. IMRangio demonstrated fair correlation with IMR. CONCLUSIONS: CMD is an independent predictor of cardiovascular mortality and HF after TAVI.

Coronary physiology assessments: historical overview and future challenges.

Coronary physiological assessment has garnered extensive application in managing patients with coronary artery disease, encompassing both acute and chronic scenarios. Beyond the historical purpose as tool to define the hemodynamic significance of a given artery lesion, coronary artery physiology allows for a complete investigation of epicardial and microvascular circulation. The longitudinal assessment of the distribution pattern of coronary disease based on pressure wire technology provides crucial information to define the best management and procedural planning. Moreover, post-percutaneous coronary intervention physiology reassessment showed a strong association with clinical outcomes and, more importantly, it can spot residual pressure gradients potentially amenable to further intervention and optimization. Growing evidence about the non-invasive angiography-based indices helps to overcome the limitations of the use of intracoronary physiology. This review aims to provide an overview of different utilizations of coronary physiology offering a historical perspective with a particular focus on current challenges and future potential applications.

Characterisation of coronary microvascular dysfunction in patients with severe aortic stenosis undergoing TAVI.

BACKGROUND: Microvascular resistance reserve (MRR) is a validated measure of coronary microvascular function independent of epicardial resistances. AIMS: We sought to assess whether MRR is associated with adverse cardiac remodelling, a low-flow phenotype and extravalvular cardiac damage (EVCD) in patients with severe aortic stenosis (AS) undergoing transcatheter aortic valve implantation (TAVI). METHODS: Invasive thermodilution-based assessment of the coronary microvascular function of the left anterior descending artery was performed in a prospective, multicentre cohort of patients undergoing TAVI. Coronary microvascular dysfunction (CMD) was defined as the lowest MRR tertile of the study cohort. Haemodynamic measurements were performed at baseline and then repeated immediately after TAVI. EVCD and markers of a low-flow phenotype were assessed with echocardiography. RESULTS: A total of 134 patients were included in this study. Patients with low MRR were more frequently females, had a lower estimated glomerular filtration rate and a higher rate of atrial fibrillation. MRR was significantly lower in patients with advanced EVCD (median 1.80 [1.26-3.30] vs 2.50 [1.87-3.41]; p=0.038) and in low-flow, low-gradient AS (LF LG-AS) (median 1.85 [1.20-3.04] vs 2.50 [1.87-3.40]; p=0.008). Overall, coronary microvascular function tended to improve after TAVI and, in particular, MRR increased significantly after TAVI in the subgroup with low MRR at baseline. However, MRR was significantly impaired in 38 (28.4%) patients immediately after TAVI. Advanced EVCD (adjusted odds ratio 3.08 [1.22-7.76]; p=0.017) and a low-flow phenotype (adjusted odds ratio 3.36 [1.08-10.47]; p=0.036) were significant predictors of CMD. CONCLUSIONS: In this observational, hypothesis-generating study, CMD was associated with extravalvular cardiac damage and a low-flow phenotype in patients with severe AS undergoing TAVI.

Angiography-Derived Index of Microcirculatory Resistance to Define the Risk of Early Discharge in STEMI.

BACKGROUND: Patients with ST-segment-elevation myocardial infarction but no coronary microvascular injury are at low risk of early cardiovascular complications (ECC). We aim to assess whether nonhyperemic angiography-derived index of microcirculatory resistance (NH-IMRangio) could be a user-friendly tool to identify patients at low risk of ECC, potentially candidates for expedited care pathway and early hospital discharge. METHODS: Retrospective analysis of 2 independent, international, prospective, observational cohorts included 568 patients with ST-segment-elevation myocardial infarction. NH-IMRangio was calculated based on standard coronary angiographic views with 3-dimensional-modeling and computational analysis of the coronary flow. RESULTS: Overall, ECC (a composite of cardiovascular death, cardiogenic shock, acute heart failure, life-threatening arrhythmias, resuscitated cardiac arrest, left ventricular thrombus, post-ST-segment-elevation myocardial infarction mechanical complications, and rehospitalization for acute heart failure or acute myocardial infarction at 30 days follow-up), occurred in 54 (9.3%) patients. NH-IMRangio was significantly correlated with pressure/thermodilution-based index of microcirculatory resistance (r=0.607; P<0.0001) and demonstrated good accuracy in predicting ECC (area under the curve, 0.766 [95% CI, 0.706-0.827]; P<0.0001). Importantly, ECC occurred more frequently in patients with NH-IMRangio ≥40 units (18.1% versus 1.4%; P<0.0001). At multivariable analysis, NH-IMRangio provided incremental prognostic value to conventional clinical, angiographic, and echocardiographic features (adjusted-odds ratio, 14.861 [95% CI, 5.177-42.661]; P<0.0001). NH-IMRangio<40 units showed an excellent negative predictive value (98.6%) in ruling out ECC. Discharging patients with NH-IMRangio<40 units at 48 hours after admission would reduce the total in-hospital stay by 943 days (median 2 [1-4] days per patient). CONCLUSIONS: NH-IMRangio is a valuable risk-stratification tool in patients with ST-segment-elevation myocardial infarction. NH-IMRangio guided strategies to early discharge may contribute to safely shorten hospital stay, optimizing resources utilization.

Cardiovascular Magnetic Resonance Before Invasive Coronary Angiography in Suspected Non-ST-Segment Elevation Myocardial Infarction.

BACKGROUND: In suspected non-ST-segment elevation myocardial infarction (NSTEMI), this presumed diagnosis may not hold true in all cases, particularly in patients with nonobstructive coronary arteries (NOCA). Additionally, in multivessel coronary artery disease, the presumed infarct-related artery may be incorrect. OBJECTIVES: This study sought to assess the diagnostic utility of cardiac magnetic resonance (CMR) before invasive coronary angiogram (ICA) in suspected NSTEMI. METHODS: A total of 100 consecutive stable patients with suspected acute NSTEMI (70% male, age 62 ± 11 years) prospectively underwent CMR pre-ICA to assess cardiac function (cine), edema (T2-weighted imaging, T1 mapping), and necrosis/scar (late gadolinium enhancement). CMR images were interpreted blinded to ICA findings. The clinical care and ICA teams were blinded to CMR findings until post-ICA. RESULTS: Early CMR (median 33 hours postadmission and 4 hours pre-ICA) confirmed only 52% (52 of 100) of patients had subendocardial infarction, 15% transmural infarction, 18% nonischemic pathologies (myocarditis, takotsubo, and other forms of cardiomyopathies), and 11% normal CMR; 4% were nondiagnostic. Subanalyses according to ICA findings showed that, in patients with obstructive coronary artery disease (73 of 100), CMR confirmed only 84% (61 of 73) had MI, 10% (7 of 73) nonischemic pathologies, and 5% (4 of 73) normal. In patients with NOCA (27 of 100), CMR found MI in only 22% (6 of 27 true MI with NOCA), and reclassified the presumed diagnosis of NSTEMI in 67% (18 of 27: 11 nonischemic pathologies, 7 normal). In patients with CMR-MI and obstructive coronary artery disease (61 of 100), CMR identified a different infarct-related artery in 11% (7 of 61). CONCLUSIONS: In patients presenting with suspected NSTEMI, a CMR-first strategy identified MI in 67%, nonischemic pathologies in 18%, and normal findings in 11%. Accordingly, CMR has the potential to affect at least 50% of all patients by reclassifying their diagnosis or altering their potential management.

Complete vs Culprit-Only Revascularization in Older Patients With Myocardial Infarction With or Without ST-Segment Elevation.

BACKGROUND: The effectiveness of complete revascularization is well established in patients with ST-segment elevation myocardial infarction (STEMI), but it is less investigated in those with non-ST-segment elevation myocardial infarction (NSTEMI). OBJECTIVES: This study aimed to assess whether complete revascularization, compared with culprit-only revascularization, was associated with consistent outcomes in older patients with STEMI and NSTEMI. METHODS: In the FIRE (Functional Assessment in Elderly MI Patients with Multivessel Disease) trial, 1,445 older patients with myocardial infarction (MI) were randomized to culprit-only or physiology-guided complete revascularization, stratified by STEMI (n = 256 culprit-only vs n = 253 complete) and NSTEMI (n = 469 culprit-only vs n = 467 complete). The primary outcome comprised a composite of death, MI, stroke, or revascularization at 1 year. The key secondary outcome included a composite of cardiovascular death or MI at 1 year. RESULTS: In the overall study population, physiology-guided complete revascularization reduced both primary and key secondary outcomes. The primary outcome occurred in 54 (21.1%) STEMI patients randomized to culprit-only vs 41 (16.2%) STEMI patients of the complete group (HR: 0.75; 95% CI: 0.50-1.13) and in 98 (20.9%) NSTEMI patients randomized to culprit-only vs 72 (15.4%) NSTEMI patients of the complete group (HR: 0.71; 95% CI: 0.53-0.97), with negative interaction testing (P for interaction, 0.846). Similarly, no signal of heterogeneity with respect to the initial clinical presentation was observed for the key secondary endpoint (P for interaction, 0.654). CONCLUSIONS: Physiology-guided complete revascularization, compared with culprit-only revascularization, provided consistent benefit across the whole spectrum of patients with MI. (FIRE [Functional Assessment in Elderly MI Patients With Multivessel Disease]; NCT03772743).

Comprehensive Angiography-Derived Functional Assessment of Epicardial and Microvascular Coronary Disease. Correlation With Non-invasive Myocardial Stress Imaging.

Coronary angiography (CA) is poorly correlated with non-invasive myocardial stress imaging (NSI) and myocardial ischemia is often observed in patients with unobstructed coronary arteries. Moreover, the diagnostic performance of combined epicardial and microcirculatory angiography-derived physiological assessment and its correlation with NSI remains unknown. A total of 917 coronary vessels in 319 patients who underwent both CA and NSI were included in this multicenter observational retrospective analysis. Quantitative flow ratio (QFR) and angiography-derived index of microcirculatory resistance (IMRangio) analyses were performed to estimate coronary epicardial and microcirculatory function respectively. NSI demonstrated evidence of myocardial ischemia in 76% of the cases. IMRangio (36 [22 to 50] vs 29 [21 to 41], p <0.001) was significantly higher and QFR (0.92 [0.78 to 0.99] vs 0.97 [0.91 to 0.99], p <0.001) was significantly lower in vessels subtending ischemic territories. Overall, the diagnostic accuracy of QFR was moderate (area under the curve of receiver operating characteristic [AUCROC] 0.632 [95% confidence interval [CI] 0.589 to 0.674], p <0.0001) but it was higher in patients with normal microcirculatory function (AUCROC = 0.726 [95% CI 0.669 to 0.784], p <0.0001, p Value for AUCROC comparison = 0.009). Combined QFR/IMRangio assessment provided incremental diagnostic performance compared with the evaluation of epicardial or microcirculatory districts in isolation (p Value for AUC comparison <0.0001) and it was able to identify the predominant mechanism of myocardial ischemia in 77% of the patients with positive NSI. Our study suggests the value of a combined angiography-derived assessment of epicardial and microvascular function for the definition of the predominant mechanism of myocardial ischemia in patients with suspected coronary artery disease.

QFR for the Revascularization of Nonculprit Vessels in MI Patients: Insights From the FIRE Trial.

BACKGROUND: The role of quantitative flow ratio (QFR) in the treatment of nonculprit vessels of patients with myocardial infarction (MI) is a topic of ongoing discussion. OBJECTIVES: This study aimed to investigate the predictive capability of QFR for adverse events and its noninferiority compared to wire-based functional assessment in nonculprit vessels of MI patients. METHODS: The FIRE (Functional Assessment in Elderly MI Patients With Multivessel Disease) trial randomized 1,445 older MI patients to culprit-only (n = 725) or physiology-guided complete revascularization (n = 720). In the culprit-only arm, angiographic projections of nonculprit vessels were prospectively collected, centrally reviewed for QFR computation, and associated with endpoints. In the complete revascularization arm, endpoints were compared between nonculprit vessels investigated with QFR or wire-based functional assessment. The primary endpoint was the vessel-oriented composite endpoint (VOCE) at 1 year. RESULTS: QFR was measured on 903 nonculprit vessels from 685 patients in the culprit-only arm. Overall, 366 (40.5%) nonculprit vessels showed a QFR value ≤0.80, with a significantly higher incidence of VOCEs (22.1% vs 7.1%; P < 0.001). QFR ≤0.80 emerged as an independent predictor of VOCEs (HR: 2.79; 95% CI: 1.64-4.75). In the complete arm, QFR was used in 320 (35.2%) nonculprit vessels to guide revascularization. When compared with propensity-matched nonculprit vessels in which treatment was guided by wire-based functional assessment, no significant difference was observed (HR: 0.57; 95% CI: 0.28-1.15) in VOCEs. CONCLUSIONS: This prespecified subanalysis of the FIRE trial provides evidence supporting the safety and efficacy of QFR-guided interventions for the treatment of nonculprit vessels in MI patients. (Functional Assessment in Elderly MI Patients With Multivessel Disease [FIRE]; NCT03772743).