Quantitative flow ratio versus fractional flow reserve for coronary revascularisation guidance (FAVOR III Europe): a multicentre, randomised, non-inferiority trial.

BACKGROUND: Fractional flow reserve (FFR) or non-hyperaemic pressure ratios are recommended to assess functional relevance of intermediate coronary stenosis. Both diagnostic methods require the placement of a pressure wire in the coronary artery during invasive coronary angiography. Quantitative flow ratio (QFR) is an angiography-based computational method for the estimation of FFR that does not require the use of pressure wires. We aimed to investigate whether a QFR-based diagnostic strategy yields a non-inferior 12-month clinical outcome compared with an FFR-based strategy. METHODS: FAVOR III Europe was a multicentre, randomised, open-label, non-inferiority trial comparing a QFR-based with an FFR-based diagnostic strategy for patients with intermediate coronary stenosis. Enrolment was performed in 34 centres across 11 European countries. Patients aged 18 years or older with either chronic coronary syndrome or stabilised acute coronary syndrome, and with at least one intermediate non-culprit stenosis (40-90% diameter stenosis by visual estimate; referred to here as a study lesion), were randomly assigned (1:1) to the QFR-guided or the FFR-guided group. Randomisation was done using a concealed web-based system and was stratified by diabetes and presence of a left anterior descending coronary artery study lesion. The primary endpoint was a composite of death, myocardial infarction, and unplanned revascularisation at 12 months. The predefined non-inferiority margin was 3·4% and the primary analysis was performed in the intention-to-treat population. The trial was registered with ClinicalTrials.gov (NCT03729739) and long-term follow-up is ongoing. FINDINGS: Between Nov 6, 2018, and July 21, 2023, 2000 patients were enrolled and randomly assigned to the QFR-guided strategy (1008 patients) or the FFR-guided strategy (992 patients). The median age was 67·3 years (IQR 59·9-74·7); 1538 (76·9%) patients were male and 462 (23·1%) were female. Median follow-up time was 365 days (IQR 365-365). At 12 months, a primary endpoint event had occurred in 67 (6·7%) patients in the QFR group, and in 41 (4·2%) patients in the FFR group (hazard ratio 1·63 [95% CI 1·11-2·41]). The event proportion difference was 2·5% (90% two-sided CI 0·9-4·2). The upper limit of the 90% CI exceeded the prespecified non-inferiority margin of 3·4%. Therefore, QFR did not meet non-inferiority to FFR. A total of 18 (1·8%) patients in each group experienced an adverse procedural event, the most frequent being procedure-related myocardial infarction, which occurred in ten (1·0%) patients in the QFR group and seven (0·7%) in the FFR group. One patient in the QFR group died in relation to the index procedure. INTERPRETATION: The results of the FAVOR III Europe trial do not support the use of QFR if FFR is available to guide revascularisation decisions in patients with intermediate coronary stenosis. This finding could have implications for current clinical guidelines recommending QFR for this purpose. FUNDING: Medis Medical Imaging Systems and Aarhus University.

Age-related structural remodelling of the coronary circulation.

BACKGROUND: While it is broadly accepted that ageing is associated with impairment of coronary microvascular function, little is known about the underlying mechanisms. AIMS: We investigated age-related changes in coronary microvascular structure in patients with stable angina without epicardial coronary stenoses. METHODS: In an analysis of the IDEAL registry, a total of 165 vessels without coronary stenosis were interrogated with combined pressure/Doppler guidewires. We calculated diastolic microvascular conductance (DMVC) and backward expansion wave (BEW), and compared them between age tertiles. We calculated the prevalence of CMD, defined by reduced coronary flow reserve (CFR), and the prevalence of low BEW and low DMVC in each group. RESULTS: The three study groups were defined as having 37-53, 54-66, and 67-77 years of age, respectively. Oldest (3rd tertile) patients showed lower hyperemic flow velocity (46.7 ± 14.4 vs. 45.1 ± 12.4 vs. 38.4 ± 11.5 cm s-1, p = 0.019), lower DMVC (1.90 ± 0.71 vs. 1.44 ± 0.56 vs. 1.37 ± 0.67 cm s-1 mmHg-1, p < 0.001) and lower BEW intensity (5.9 [2.9-8.4] vs. 4.8 [2.9-6.8] vs. 4.4 [3.4-6.3] × 106 W m-2 s-1, p = 0.094). Older age was independently associated with lower BEW intensity (B: -0.10, 95% confidence interval [CI]: -0.17 to -0.09, p = 0.021) and DMVC (B: -0.25 95% CI: -0.45 to -0.09, p = 0.027). In patients with CFR < 2.5, the prevalence of BEW intensity and DMVC below the 25th percentile increased with age (25.0% vs. 52.0% vs. 72.7%, p = 0.010). CONCLUSIONS: Ageing is independently associated with structural microcirculatory remodeling that is reflected in BEW intensity and DMVC measurements, and with an increased prevalence of structural CMD. These results are important to understand non-obstructive mechanisms of myocardial ischemia in the elderly.

Coronary microvascular dysfunction is associated with impaired cognitive function: the Cerebral-Coronary Connection study (C3 study).

BACKGROUND: It remains unknown whether the presence of coronary microcirculatory dysfunction (CMD) correlates with its equivalent condition in the brain, cerebral small vessel disease (CSVD). The cerebral-coronary connection (C3), a prospective blinded study, investigated the prevalence of CMD in patients with coronary artery disease (CAD) and its association with CSVD and cognitive function. METHODS AND RESULTS: Patients with documented CAD fulfilling inclusion criteria underwent physiological assessment of epicardial vessels and the microcirculation using intracoronary pressure and Doppler. Coronary microcirculation-related indices included coronary flow reserve (CFR) and hyperaemic microvascular resistance. Brain magnetic resonance imaging, transcranial Doppler (TCD), and neurocognitive examination were performed. Overall, 67 patients were included in the study (mean age 66 years, 73% female). Patients with abnormal CFR (<2.0) (55.2%) showed higher burden of white-matter hyperintensities: 43.2 vs. 20.0% (P = 0.044). After statistical adjustment, low CFR was associated with lower grey matter volume (P = 0.024) and with parameters of white-matter microstructural damage in diffusion-tensor imaging (lower fractional anisotropy and higher mean diffusivity, P = 0.029 and P = 0.032, respectively). Low CFR was associated with higher resistive (P = 0.027) and pulsatility (P = 0.043) values on TCD, and worse neurocognitive test scores (lower mini mental state examination, P = 0.025, and slower Trail Making Test A, P = 0.034). CONCLUSIONS: Coronary microcirculatory dysfunction is frequent in patients with CAD and correlates with CSVD, abnormal cerebral flow haemodynamics, and significant cognitive impairment. These findings support the hypothesis that microvascular dysfunction in the heart and the brain are part of a single pathological process affecting microcirculation in patients with CAD. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov NCT04131075.

Microvascular resistance reserve: diagnostic and prognostic performance in the ILIAS registry.

AIMS: The microvascular resistance reserve (MRR) was introduced as a means to characterize the vasodilator reserve capacity of the coronary microcirculation while accounting for the influence of concomitant epicardial disease and the impact of administration of potent vasodilators on aortic pressure. This study aimed to evaluate the diagnostic and prognostic performance of MRR. METHODS AND RESULTS: A total of 1481 patients with stable symptoms and a clinical indication for coronary angiography were included from the global ILIAS Registry. MRR was derived as a function of the coronary flow reserve (CFR) divided by the fractional flow reserve (FFR) and corrected for driving pressure. The median MRR was 2.97 [Q1-Q3: 2.32-3.86] and the overall relationship between MRR and CFR was good [correlation coefficient (Rs) = 0.88, P < 0.005]. The difference between CFR and MRR increased with decreasing FFR [coefficient of determination (R2) = 0.34; Coef.-2.88, 95% confidence interval (CI): -3.05--2.73; P < 0.005]. MRR was independently associated with major adverse cardiac events (MACE) at 5-year follow-up [hazard ratio (HR) 0.78; 95% CI 0.63-0.95; P = 0.024] and with target vessel failure (TVF) at 5-year follow-up (HR 0.83; 95% CI 0.76-0.97; P = 0.047). The optimal cut-off value of MRR was 3.0. Based on this cut-off value, only abnormal MRR was significantly associated with MACE and TVF at 5-year follow-up in vessels with functionally significant epicardial disease (FFR <0.75). CONCLUSION: MRR seems a robust indicator of the microvascular vasodilator reserve capacity. Moreover, in line with its theoretical background, this study suggests a diagnostic advantage of MRR over other indices of vasodilatory capacity in patients with hemodynamically significant epicardial coronary artery disease.

Angiography-derived functional assessment of left main coronary stenoses.

OBJECTIVES: We aimed to evaluate the diagnostic accuracy of quantitative flow ratio (QFR) in left main (LM) coronary stenoses, using Fractional Flow Reserve (FFR) as reference. BACKGROUND: QFR has demonstrated a high accuracy in determining the functional relevance of coronary stenoses in non-LM. However, there is an important paucity of data regarding its diagnostic value in the specific anatomical subset of LM disease. METHODS: This is a retrospective, observational, multicenter, international, and blinded study including patients with LM stenoses. Cases with significant ostial LM disease were excluded. QFR was calculated from conventional angiograms at blinded fashion with respect to FFR. RESULTS: Sixty-seven patients with LM stenoses were analyzed. Overall, LM had intermediate severity, both from angiographic (diameter stenosis [%DS] 43.8 ± 11.1%) and functional perspective (FFR 0.756 ± 0.105). Mean QFR was 0.733 ± 0.159. Correlation between QFR and FFR was moderate (r = 0.590). Positive and negative predictive value, sensitivity and specificity were 85.4%, 64%, 85.4%, and 69.6% respectively. Classification agreement of QFR and FFR in terms of functional stenosis severity was 78.1%. Area under the receiver operating characteristics of QFR using FFR as reference was 0.82 [95% confidence interval [CI], 0.71-0.93], and significantly better than angiographic evaluation including %DS (area under the receiver-operating characteristic curve [AUC] 0.45 [95% CI, 0.32-0.58], p < 0.001) and minimum lumen diameter (AUC 0.60 [95% CI, 0.47-0.74], p < 0.001). CONCLUSIONS: Compared with FFR, QFR has acceptable diagnostic performance in determining the functional relevance of LM stenosis, being better than conventional angiographic assessment. Nonetheless, caution should be taken when applying functional angiography techniques for the assessment of LM stenosis given its particular anatomical characteristics.

Association between patient age, microcirculation, and coronary stenosis assessment with fractional flow reserve and instantaneous wave-free ratio.

OBJECTIVES: To investigate the effect of aging on coronary stenosis functional assessment with fractional flow reserve (FFR) and instantaneous wave-free ratio (iFR). BACKGROUND: Limited data exist regarding the impact of patient age on these coronary pressure indices. METHODS: We analyzed 514 patients with coronary stenosis interrogated with intravascular physiology. The influence of patient age on FFR, iFR, and microcirculation-related indices was investigated. Vessel-oriented composite outcome (VOCO) was assessed in the FFR-based deferred population according to iFR, coronary flow reserve (CFR), and age. RESULTS: FFR increased (r = 0.128, p = 0.004), iFR remained unchanged (r = -0.001, p = 0.980), and CFR decreased (r = -0.095, p = 0.001) with patient age. Relationship between FFR and CFR differed across age groups (r = 0.263 in <60 years old vs. r = 0.124 in ≥60 years old, p = 0.0056), whereas iFR correlated to CFR similarly regardless age (r = 0.283 in <60 years old vs. r = 0.219 in ≥60 years old, p = 0.3781). No differences were found on angiographic stenosis severity (%DS 47.4 in <60 years old and 49.8 in ≥60 years old, p = 0.317). At 5 years, FFR-based revascularisation deferral in patients ≥60 years old was associated with more VOCO when either iFR (25%) or CFR (16.9%) were abnormal, compared to patients with normal iFR (6.3%) or normal CFR (4.6%) (log-rank p < 0.001). This difference in clinical outcomes was not observed in younger patients. CONCLUSIONS: FFR values increased progressively with patient age, potentially associated with age-related changes in the coronary microcirculation. Conversely, iFR values remained unchanged across the patient age spectrum. In ≥60 years old patients with revascularisation deferral based on FFR, both abnormal iFR and CFR values were associated with worse long-term patient outcomes.

Age-related changes in the coronary microcirculation influencing the diagnostic performance of invasive pressure-based indices and long-term patient prognosis.

OBJECTIVES: Investigate age-related changes in coronary microvascular function, its effect on hyperemic and non-hyperemic indices of stenosis relevance, and its prognostic implications. BACKGROUND: Evidence assessing the effect of age on fractional flow reserve (FFR), resting mean distal intracoronary pressure/mean aortic pressure (Pd/Pa), and microcirculatory function remains scarce. METHODS: This is a post hoc study of a large prospective international registry (NCT03690713) including 1134 patients (1326 vessels) with coronary stenoses interrogated with pressure and flow guidewires. Age-dependent correlations with functional indices were analyzed. Prevalences of FFR, resting Pd/Pa, and coronary flow reserve (CFR) classification agreement were assessed. At 5 years follow-up, the relation between resting Pd/Pa, CFR, and their age-dependent implications on FFR-guided percutaneous coronary intervention (PCI) deferral (deferred if FFR > 0.80) were investigated using vessel-oriented composite outcomes (VOCO) composed of death, myocardial infarction, and repeated revascularization. RESULTS: Age correlated positively with FFR (r = 0.08, 95% confidence interval [CI]: 0.03 to 0.13, p = 0.005), but not with resting Pd/Pa (r = -0.03, 95% CI:-0.09 to 0.02, p = 0.242). CFR correlated negatively with age (r = -0.15, 95% CI: -0.21 to -0.10, p < 0.001) due to a significant decrease in maximal hyperemic flow in older patients. Patients over 60 years of age with FFR-guided deferred-PCI abnormal resting Pd/Pa or abnormal CFR had increased risk of VOCO (hazard ratio [HR]: 2.10, 95% CI: 1.15 to 4.36, p = 0.048; HR: 2.46, 95% CI:1.23 to 4.96, p = 0.011; respectively). CONLUSIONS: Aging is associated with decrease in microcirculatory vasodilation, as assessed with adenosine-based methods like CFR. In patients older than 60 years in whom PCI is deferred according to FFR > 0.80, CFR and resting Pd/Pa have an incremental value in predicting future vessel-oriented patient outcomes.

Prediction of functional results of percutaneous coronary interventions with virtual stenting and quantitative flow ratio.

BACKGROUND: The clinical value of residual quantitative flow ratio (rQFR), a novel function of QFR technique, is unknown. AIM: We investigated the clinical value of rQFR, aimed to predict residual ischemia after virtual percutaneous coronary intervention (vPCI). METHODS: This is a substudy of the COE-PERSPECTIVE registry, which investigated the prognostic value of post-PCI fractional flow reserve (FFR). From pre-PCI angiograms, QFR and rQFR were analyzed and their diagnostic performance was assessed at blinded fashion using pre-PCI FFR and post-PCI FFR as reference, respectively. The prognostic value of rQFR after vPCI was assessed according to vessel-oriented composite outcome (VOCO) at 2 years. RESULTS: We analyzed 274 patients (274 vessels) with FFR-based ischemic causing lesions (49%) from 555 screened patients. Pre-PCI QFR and FFR were 0.63 ± 0.10 and 0.66 ± 0.11 (R = 0.756, p < 0.001). rQFR after vPCI and FFR after real PCI were 0.93 ± 0.06 and 0.86 ± 0.07 (R = 0.528, p < 0.001). The mean difference between rQFR and post-PCI FFR was 0.068 (95% limit of agreement: -0.05 to 0.19). Diagnostic performance of rQFR to predict residual ischemia after PCI was good (area under the curve [AUC]: 0.856 [0.804-0.909], p < 0.001). rQFR predicted well the incidence of 2-year VOCO after index PCI (AUC: 0.712 [0.555-0.869], p = 0.041), being similar to that of actual post-PCI FFR (AUC: 0.691 [0.512-0.870], p = 0.061). rQFR ≤0.89 was associated with increased risk of 2-year VOCO (hazard ratio [HR]: 12.9 [2.32-71.3], p = 0.0035). This difference was mainly driven by a higher rate of target vessel revascularization (HR: 16.98 [2.33-123.29], p = 0.0051). CONCLUSIONS: rQFR estimated from pre-PCI angiography and virtual coronary stenting mildly overestimated functional benefit of PCI. However, it well predicted suboptimal functional result and long-term vessel-related clinical events. CLINICAL TRIAL REGISTRATION: Influence of fractional flow reserve on the Clinical OutcomEs of PERcutaneouS Coronary Intervention (COE-PESPECTIVE) Registry, NCT01873560.

Long-term outcomes after deferral of revascularization of in-stent restenosis using fractional flow reserve.

OBJECTIVES: To investigate the outcomes of deferred coronary revascularization in patients with non-significant in-stent restenosis (ISR) by physiological assessment. BACKGROUND: The pathophysiology and natural history of ISR is markedly different from de-novo stenoses. There is a paucity of data on the safety of deferral of revascularization of ISR using physiological assessment. METHODS: In this single centre study, using a propensity-score matched analysis, we compared the long-term clinical outcomes of patients with ISR and de-novo disease deferred based on intracoronary physiology. Matching was on a 1:2 basis of ISR to de-novo stenosis. The primary end point was major adverse cardiovascular events (MACE) a composite of all-cause mortality, target lesion revascularization or target vessel myocardial infarction at 36 months. RESULTS: Matched cohorts of 56 ISR and 112 de-novo stenoses were analyzed. The median percentage stenosis was 50% in both groups (p = 0.403). Deferral was based on fractional flow reserve (FFR). The mean FFR was 0.86 across both groups (p = 0.942). At 36-months, freedom from MACE was similar between groups; 86.2% versus 92.8% log rank p=0.180 for ISR and de-novo lesions, respectively. Neither were there differences in the individual components of MACE. CONCLUSIONS: Deferral of coronary revascularization in patients with ISR based on its functional impact is associated to similar long-term safety as in de-novo coronary stenosis.

Invasive evaluation of coronary microvascular dysfunction.

Coronary microvascular dysfunction (CMD) is a prevalent cause of ischemic heart disease and is associated with poorer quality of life and worse patient outcomes. Both functional and structural abnormalities of the microcirculation can generate ischemia in the absence of epicardial stenosis or worsen concomitant obstructive coronary artery disease (CAD). The invasive assessment of CMD allows for the evaluation of the entirety of the coronary vascular tree, from the large epicardial vessels to the microcirculation, and enables the study of vasomotor function through vasoreactivity testing. The standard evaluation of CMD includes vasomotor assessment with acetylcholine, as well as flow- and resistance-derived indices calculated with either thermodilution or Doppler guidewires. Tailored treatment based upon the information gathered from the invasive evaluation of CMD has been demonstrated to reduce the burden of angina; therefore, a thorough understanding of these procedures is warranted with the aim of improving the quality of life of the patient. This review summarizes the most widespread approaches for the invasive evaluation of CMD, with a focus on patients with ischemia and non-obstructive CAD.

Vascular Injury After Stenting　- Insights of Systemic Mechanisms of Vascular Repair.

BACKGROUND: The role of circulating progenitor cells (CPC) in vascular repair following everolimus-eluting stent (EES) implantation is largely unknown. The aim of the study was to investigate the relationship between temporal variation in CPC levels following EES implantation and the degree of peri-procedural vascular damage, and stent healing, as measured by optical coherence tomography (OCT).Methods and Results: CPC populations (CD133+/KDR+/CD45low) included patients with stable coronary artery disease undergoing stent implantation, and were evaluated using a flow cytometry technique both at baseline and at 1 week. OCT evaluation was performed immediately post-implantation to quantify the stent-related injury and at a 9-month follow up to assess the mid-term vascular response. Twenty patients (mean age 66±9 years; 80% male) with EES-treated stenoses (n=24) were included in this study. Vascular injury score was associated with the 1-week increase of CD133+/KDR+/CD45low (ß 0.28 [95% CI 0.15; 0.41]; P<0.001) and with maximum neointimal thickness at a 9-month follow up (ß 0.008 [95% CI 0.0004; 0.002]; P=0.04). Inverse relationships between numbers of uncoated and apposed struts for the 9-month and the 1-week delta values of CD133+/KDR+/CD45low (ß -12.53 [95% CI -22.17; -2.90]; P=0.011), were also found. CONCLUSIONS: The extent of vessel wall injury influences early changes in the levels of CPC and had an effect on mid-term vascular healing after EES implantation. Early CPC mobilisation was associated with mid-term strut coverage.

Coronary microcirculation assessment using functional angiography: Development of a wire-free method applicable to conventional coronary angiograms.

OBJECTIVES: We aimed to develop a novel wire- and adenosine-free microcirculatory resistive index from functional angiography (angio-IMR) to estimate coronary microcirculatory resistance, and to investigate how this method can improve clinical interpretation of physiological stenosis assessment with quantitative flow ratio (QFR). BACKGROUND: Hyperemic index of coronary microcirculatory resistance (IMR) is a widely used tool to assess microcirculatory dysfunction. However, the need of dedicated intracoronary wire and hyperemia limits its adoption in clinical practice. METHODS: We performed our study in two separate stages: (1) development of a formula (angio-IMR) to estimate IMR from resting angiograms and aortic pressure (Pa), and (2) validation of the method in a clinical population using invasively measured IMR as reference. Additionally, QFR diagnostic performance was assessed considering angio-IMR values. RESULTS: We developed the formula: angio-IMR = (Pa-[0.1*Pa])*QFR*e-Tmn (where e-Tmn is an estimation of hyperaemic mean transit time) and validated it in 115 vessels (104 patients). Angio-IMR correlated well with IMR (Spearman's rho = 0.70, p < 0.001). Sensitivity, specificity, positive and negative predictive value, accuracy and area under the curve of angio-IMR to predict IMR were 87.5% (73.2-95.8), 85.3% (75.3-92.4), 76.1% (64.5-84.8), 92.8% (84.9-96.7), 85% and 0.90 (0.83-0.95), respectively. False positive QFR measurements decreased from 19.5% to 8.5% when angio-IMR was incorporated into the QFR interpretation workflow. CONCLUSIONS: Estimation of IMR without physiology wire and adenosine is feasible. Coronary microcirculatory dysfunction causing high IMR can be ruled-out with high confidence in vessels with low angio-IMR. Awareness of angio-IMR contributes to a better clinical interpretation of functional stenosis assessment with QFR.

Anatomical and functional healing after resorbable magnesium scaffold implantation in human coronary vessels: A combined optical coherence tomography and quantitative flow ratio analysis.

BACKGROUND: No data are currently available on the process of vessel healing and long-term physiological results after implantation of resorbable magnesium-made scaffold (RMS) in human coronary arteries. OBJECTIVES: To investigate after percutaneous coronary intervention (PCI) and at 12 months follow-up (a) RMS resorption process and vessel healing, as judged by optical coherence tomography (OCT) imaging; and (b) physiological result of RMS implantation evaluated by quantitative flow ratio (QFR). METHODS: All patients successfully treated with at least one RMS from July 2016 to August 2018 at 2 Italian centers were evaluated. All cases with OCT pullback and/or coronary angiography suitable for QFR analysis performed after PCI and at 12 months were included. Resorption process was analyzed at OCT in each frame reporting presence of residual struts in the vessel. RESULTS: Forty-four patients/forty-nine lesions were included. 12-months mean lumen area (LA; 7.54 ± 3.04 mm2 ) significantly decreased compared to mean LA recorded immediately after PCI (8.12 ± 1.89 mm2 ; p < .01). However, LA changes did not affect the functional result of PCI with a non-ischemic QFR value (>0.80) in 98% of cases at 12-months follow-up. Protruding struts were detectable in more than half of cases and their presence was correlated with an increase in mean LA (+0.73mm2 [95% CI 0.51-0.94], p < .001). CONCLUSIONS: RMS implantation in a real-world population lead to significant decrease in mean LA without significant functional impairment. Two different patterns of RMS resorption were recorded, whose clinical significance remains to be investigated.

Dose-reducing fluoroscopic system decreases patient but not occupational radiation exposure in chronic total occlusion intervention.

AIMS: Several novel low-dose fluoroscopic systems (LDS) developed recently, but real practice information of the net benefit for the patient and professionals is scarce. We evaluated separately patient and operator radiation exposure during percutaneous interventions of chronic total occlusions (CTO). METHODS: A total of 116 consecutive CTOs were analyzed (60 in LDS and 56 in standard-dose fluoroscopic system [SDS]). Digital dosimetry of patient and occupational (operator and scatter dose) exposure was prospectively recorded. RESULTS: Biometrics, demographics, CTO variables, and operators were distributed evenly. Patient radiation exposure was effectively decreased in LDS (dose area product [DAP] by 36%, Air Kerma [AK] by 47%). However, occupational data showed no statistical differences between LDS and SDS. The LDS uses less radiation amount but with higher energy (due to additional filtration) compared to SDS, therefore increasing the scatter dose. When comparing the C-arm scatter dose to the DAP we found higher scatter dose with the LDS (0.0139 mSv/gray (Gy)*cm2 vs. 0.0082 mSv/Gy*cm2, p < .001). This was confirmed in a larger dataset comprising 5,221 coronary procedures. CONCLUSIONS: LDS was safer for patients reducing DAP and AK compared to SDS. However, occupational doses were not lower and scatter dose higher. Radiological protection measures must be kept maximized even in LDS.

Performance of the heart team approach in daily clinical practice in high-risk patients with aortic stenosis.

OBJECTIVE: The heart team (HT) approach plays a key role in selecting the optimal treatment strategy for patients with aortic stenosis (AS). However, little is known about the HT decision process and its impact on outcomes. The aim of this study was to identify the factors associated with the HT decision and evaluate clinical outcomes according to the treatment choice. METHODS: The study included a total of 286 consecutive patients with AS referred for discussion in the weekly HT meeting in a cardiovascular institute over 2 years. Patients were stratified according to the selected therapeutic approach: medical treatment (MT), surgical (SAVR), or transcatheter (TAVR) aortic valve replacement. Baseline characteristics involved in making a therapeutic choice were identified and a decision-making tree was built using classification and regression tree methodology. RESULTS: Based on HT discussion, 53 patients were assigned to SAVR, 210 to TAVR, and 23 to MT. Older patients (≥88 years old) were mainly assigned to TAVR or MT according to the logistic EuroSCORE (

Clinical Profile and 30-Day Mortality of Invasively Managed Patients with Suspected Acute Coronary Syndrome During the COVID-19 Outbreak.

The COVID-19 pandemic severely disrupted cardiovascular care during the spring of 2020 in Europe. Our study analyzed the clinical profile, COVID-19 impact, and 30-day prognosis of invasively managed patients with acute coronary syndrome (ACS) compared to a historical cohort.All invasively managed ACS patients from March 1st to April 30th, 2020 were compared to a cohort from the same timeframe of 2019 (n = 316). COVID-19 confirmed cases were defined by a positive SARS-CoV-2 polymerase chain reaction (PCR) test (CoV+). The primary outcome was all-cause 30-day mortality and multivariable predictors of this outcome.A 40.4% reduction in ACS patients was noted (198 cases in 2019 to 118 in 2020), and 11% of 2020 ACS patients were CoV+. Baseline characteristics were similar between groups. There were significantly more in-hospital patients with ACS (15.3% versus 6.1%, P = 0.007), and fewer patients were found to have a culprit lesion (58.5% versus 74.2%, P = 0.004) in 2020 compared to 2019. Thirty-day mortality in 2020 (7%) was not different from that in 2019 (4.2%), P = 0.294, but it was significantly higher in CoV+ patients (23.1%) compared to that in negative SARS-CoV-2 PCR test (CoV-) patients (5%), P = 0.047, in the 2020 group. In the multivariate analysis, CoV+ was an independent mortality predictor (OR = 9.8, 95% CI = 1.48-64.78), along with the left ventricular ejection fraction (LVEF) (OR = 0.91, 95% CI = 0.86-0.97), P = 0.0006.This study found increased 30-day mortality of invasively managed CoV+ ACS patients compared to that of CoV- patients during the 2020 COVID-19 spring outbreak. In the multivariable analysis, a SARS-CoV-2 positive test was independently associated with 30-day mortality. Further investigations of the underlying physiopathological relations between COVID-19 and ACS are warranted.

Short-term clinical outcomes of percutaneous coronary intervention of unprotected left main coronary disease in cardiogenic shock.

BACKGROUND: Percutaneous coronary intervention (PCI) of left main (LM) disease in patients with cardiogenic shock (CS) represents a clinical challenge. Evidence on clinical outcomes according to revascularization strategies in this scenario remains scarce. The objective was to investigate the short-term outcomes according to treatment strategies for this population. METHODS: We retrospectively analyzed 78 consecutive patients who underwent PCI of LM in established CS at two experienced centers. Characteristics of PCI and short-term clinical outcomes were assessed. RESULTS: LM stenosis was considered the culprit lesion in 49 patients (62.8%). In the remaining cases, LM stenosis was treated after successful PCI of the culprit vessel because of persistent CS. The majority of patients presented complex coronary anatomy (43.6% had Syntax score > 32). Complete revascularization was performed in 34.6%; a 2-stents technique in the LM bifurcation was used in 12.8% and intra-aortic balloon pump (IABP) in 73.1%. In-hospital mortality was 48.7%. At 90 days follow-up it was 50% without differences between 1 or 2 stent LM bifurcation-techniques (p = .319). Mortality was higher in patients with partial revascularization and residual Syntax score ≥ 15 (p < .05 by univariate analysis), and in those with TIMI flow<3 in the left coronary artery at the end of PCI (p < .05 by multivariate analysis). There were no significant differences in the use of IABP in relation to 90-day mortality (p = .92). CONCLUSIONS: In patients presenting with cardiogenic shock and LM disease, neither 2-stents strategy in the LM nor use of IABP displayed a reduced short-term mortality. However, patients with final TIMI flow <3 presented higher short-term mortality in our series.

Prediction of long-term patient outcome after contemporary left main stenting using the SYNTAX and SYNTAX II scores: A comparative analysis from the FAIL-II multicenter registry (failure in left main study with 2nd generation stents-Cardiogroup III study).

AIMS: To establish the value of the SYNTAX Score-II (SS-II) in predicting long-term mortality of patients treated with left main PCI (LM-PCI) using second-generation drug-eluting stents (DES). METHODS AND RESULTS: The SYNTAX score (SS) and the SS-II were calculated in 804 patients included in the FAILS-2 registry (failure in left main study with 2nd generation stents). Patients were classified in low (SS-II ≤33; n = 278, 34.6%), intermediate (SS-II 34-43; n = 260, 32.3%) and high (SS-II ≥44; n = 266, 33.1%) SS-II tertiles. Primary endpoint was all-cause mortality. A significant difference in long-term mortality was noted (5.2 ± 3.6 years): 4.1, 7.5, and 16.7% in low, mid and high SS-II tertiles respectively (p < .001). SS-II score was more accurate in predicting mortality than SS (AUC = 0.73; 95%CI: 0.67-0.79 vs. AUC = 0.55; 95%CI: 0.48-0.63, respectively; p < .001). SS-II led to a reclassification in the risk of all-cause mortality re-allocating 73% of patients from the CABG-only indication to PCI or equipoise PCI-or-CABG indication. Using multiple Cox regression analysis, SS-II (HR: 1.07; 95%CI: 1.05-1.09; p < .001), along with Acute coronary syndrome (ACS) (HR: 1.66; 95%CI: 1.03-2.66; p = .07) and Cardiogenic shock (CS) (HR: 2.82 (95%CI: 1.41-5.64; p = .003) were independent predictors of long-term mortality. SS-II (HR: 1.05; 95%CI: 1.04-1.06; p < .001) along with Insulin dependent Type 2 DM (HR: 1.58, 95%CI: 1.09-2.30.; p < .05), ACS (HR: 1.58, 95%CI: 1.16-2.14; p < .001) and CS (HR: 2.02 95%CI 1.16-3.53; p < .05), were independent predictors of long-term MACE. CONCLUSION: The SS-II was superior to the SS in predicting outcomes associated with contemporary LM-PCI. In this real-world population, two clinical variables not included in the SS-II, ACS and T2DM, were identified as additional markers of poor outcome.

Role of Invasive and Non-invasive Imaging Tools in the Diagnosis and Optimal Treatment of Patients with Spontaneous Coronary Artery Dissection.

PURPOSE OF REVIEW: Spontaneous coronary artery dissection (SCAD) is a serious non-atherosclerotic disease, most frequently presenting as an acute coronary syndrome and affecting female patients. Considering that diagnosis of SCAD is often elusive, and its interventional treatment is associated to a higher rate of complications than obstructive atherosclerotic disease, we aim to review all the imaging tools currently available for the optimal diagnosis and treatment of this condition. RECENT FINDINGS: The developments in both invasive and non-invasive imaging alternatives to coronary angiography, such as intravascular ultrasound, optical coherence tomography, and computed coronary angiography, have largely contributed to appraise the epidemiology of SCAD, understand its causative pathophysiological mechanisms, and improve our ability to confirm doubtful cases of SCAD. Intracoronary imaging is also a valuable in deciding the best therapeutic approach and in guiding interventions in those patients requiring percutaneous treatment. Furthermore, non-invasive imaging is a key tool in ruling out significant extracoronary vascular abnormalities which frequently occur in patients with underlying conditions like fibromuscular dysplasia who develop SCAD. Main imaging tools employed in SCAD cases could have advantages and drawbacks. Focusing on different types of SCAD, operators should be able to choose the best imaging technique for diagnosis, management, and follow-up.

PRotective Effect on the coronary microcirculation of patients with DIabetes by Clopidogrel or Ticagrelor (PREDICT): study rationale and design. A randomized multicenter clinical trial using intracoronary multimodal physiology.

BACKGROUND: In diabetic patients a predisposed coronary microcirculation along with a higher risk of distal particulate embolization during primary percutaneous intervention (PCI) increases the risk of peri-procedural microcirculatory damage. However, new antiplatelet agents, in particular Ticagrelor, may protect the microcirculation through its adenosine-mediated vasodilatory effects. METHODS: PREDICT is an original, prospective, randomized, multicenter controlled study designed to investigate the protective effect of Ticagrelor on the microcirculation during PCI in patient with diabetes mellitus type 2 or pre-diabetic status. The primary endpoints of this study aim to test (i) the decrease in microcirculatory resistance with antiplatelet therapy (Ticagrelor > Clopidogrel; mechanistic effect) and (ii) the relative microcirculatory protection of Ticagrelor compared to Clopidogrel during PCI (Ticagrelor < Clopidogrel; protective effect). CONCLUSIONS: PREDICT will be the first multicentre clinical trial to test the adenosine-mediated vasodilatory effect of Ticagrelor on the microcirculation during PCI in diabetic patients. The results will provide important insights into the prospective beneficial effect of this drug in preventing microvascular impairment related to PCI ( http://www.clinicaltrials.gov No. NCT02698618).