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.

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.

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.

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.

Intracoronary physiology-guided percutaneous coronary intervention in patients with diabetes.

OBJECTIVE: The risk of vessel-oriented cardiac adverse events (VOCE) in patients with diabetes mellitus (DM) undergoing intracoronary physiology-guided coronary revascularization is poorly defined. The purpose of this work is to evaluate the risk of VOCE in patients with and without DM in whom percutaneous coronary intervention (PCI) was performed or deferred based on pressure-wire functional assessment. METHODS: This is a retrospective analysis of a multicenter registry of patients evaluated with fractional flow reserve (FFR) and/or non-hyperaemic pressure ratio (NHPR). Primary endpoint was a composite of VOCE including cardiac death, vessel-related myocardial infarction (MI), and ischemia-driven target vessel revascularization (TVR). RESULTS: A large cohort of 2828 patients with 3353 coronary lesions was analysed to assess the risk of VOCE at long-term follow-up (23 [14-36] months). Non-insulin-dependent-DM (NIDDM) was not associated with the primary endpoint in the overall cohort (adjusted Hazard Ratio [aHR] 1.18, 95% CI 0.87-1.59, P = 0.276) or in patients with coronary lesions treated with PCI (aHR = 1.30, 95% CI 0.78-2.16, P = 0.314). Conversely, insulin-dependent diabetes mellitus (IDDM) demonstrated an increased risk of VOCE in the overall cohort (aHR 1.76, 95% CI 1.07-2.91, P = 0.027), but not in coronary lesions undergoing PCI (aHR 1.26, 95% CI 0.50-3.16, P = 0.621). Importantly, in coronary lesions deferred after functional assessment IDDM (aHR 2.77, 95% CI 1.11-6.93, P = 0.029) but not NIDDM (aHR = 0.94, 95% CI 0.61-1.44, P = 0.776) was significantly associated with the risk of VOCE. IDDM caused a significant effect modification of FFR-based risk stratification (P for interaction < 0.001). CONCLUSION: Overall, DM was not associated with an increased risk of VOCE in patients undergoing physiology-guided coronary revascularization. However, IDDM represents a phenotype at high risk of VOCE.

Proof of concept study on coronary microvascular function in low flow low gradient aortic stenosis.

OBJECTIVES: We hypothesised that low flow low gradient aortic stenosis (LFLGAS) is associated with more severe coronary microvascular dysfunction (CMD) compared with normal-flow high-gradient aortic stenosis (NFHGAS) and that CMD is related to reduced cardiac performance. METHODS: Invasive CMD assessment was performed in 41 consecutive patients with isolated severe aortic stenosis with unobstructed coronary arteries undergoing transcatheter aortic valve implantation (TAVI). The index of microcirculatory resistance (IMR), resistive reserve ratio (RRR) and coronary flow reserve (CFR) were measured in the left anterior descending artery before and after TAVI. Speckle tracking echocardiography was performed to assess cardiac function at baseline and repeated at 6 months. RESULTS: IMR was significantly higher in patients with LFLGAS compared with patients with NFHGAS (24.1 (14.6 to 39.1) vs 12.8 (8.6 to 19.2), p=0.002), while RRR was significantly lower (1.4 (1.1 to 2.1) vs 2.6 (1.5 to 3.3), p=0.020). No significant differences were observed in CFR between the two groups. High IMR was associated with low stroke volume index, low cardiac output and reduced peak atrial longitudinal strain (PALS). TAVI determined no significant variation in microvascular function (IMR: 16.0 (10.4 to 26.1) vs 16.6 (10.2 to 25.6), p=0.403) and in PALS (15.9 (9.9 to 26.5) vs 20.1 (12.3 to 26.7), p=0.222). Conversely, left ventricular (LV) global longitudinal strain increased after TAVI (-13.2 (8.4 to 16.6) vs -15.1 (9.4 to 17.8), p=0.047). In LFLGAS, LV systolic function recovered after TAVI in patients with preserved microvascular function but not in patients with CMD. CONCLUSIONS: CMD is more severe in patients with LFLGAS compared with NFHGAS and is associated with low-flow state, left atrial dysfunction and reduced cardiac performance.

Angiography-derived index of microvascular resistance in takotsubo syndrome.

Coronary microvascular dysfunction (CMD) has been proposed as a key driver in the etiopathogenesis of Takotsubo syndrome (TTS), likely related to an "adrenergic storm" upon a susceptible microvascular circulation. The aim of our manuscript was to assess CMD in patients with TTS through the computation of the angiography-derived index of microcirculatory resistance (IMR) and its correlation with clinical presentation. Coronary angiograms of 41 consecutive TTS patients were retrospectively analyzed to derive angiography-based indices of CMD. Three indices (NH-IMRangio, AngioIMR and A-IMR) were calculated based on quantitative flow ratio. CMD was defined as an IMRangio value ≥ 25 units. The correlation between CMD and clinical presentation was then assessed. Median age was 76 years, 85.7% were women and mean left ventricular ejection fraction (LVEF) at first echocardiogram was 41.2%. Angiography-derived IMR was higher in left anterior descending artery (LAD) than circumflex and right coronary artery with either NH-IMRangio (53.9 ± 19.8 vs 35.8 ± 15.4 vs 40.8 ± 18.5, p-value < 0.001), AngioIMR (47.2 ± 17.3 vs 31.8 ± 12.2 vs 37.3 ± 13.7, p-value < 0.001) or A-IMR (52.7 ± 19 vs 36.1 ± 14.1 vs 41.8 ± 16.1, p-value < 0.001). All patients presented CMD with angiography-derived IMR ≥ 25 in at least one territory with each formula. Angiography-derived IMR in LAD territory was significantly higher in patients presenting with LVEF impairment (≤ 40%) than in those with preserved ventricular global function (NH-IMRangio: 59.3 ± 18.1 vs 46.3 ± 16.0 p-value = 0.030; AngioIMR: 52.9 ± 17.8 vs 41.4 ± 14.2, p-value = 0.037; A-IMR: 59.2 ± 18.6 vs 46.3 ± 17.0, p-value = 0.035). CMD assessed with angiography-derived IMR is a common finding in TTS and it is inversely correlated with LV function. The available formulas have a substantial superimposable diagnostic performance in assessing coronary microvascular function.

Functional Patterns of Coronary Disease: Diffuse, Focal, and Serial Lesions.

The physiological assessment of coronary lesions is influenced by the pattern and distribution of coronary artery disease (CAD), including focal lesions, serial lesions, diffuse disease, and mixed patterns. These various patterns of CAD impact the accuracy of pressure wire and angiography-derived physiology indexes, and diffuse disease in particular is an important determinant of the anticipated outcome of percutaneous coronary intervention. Therefore, identification of the physiological pattern of disease provides relevant information for the management of CAD and percutaneous coronary intervention procedural planning. At present, the classification of physiological patterns and its implications for the tailored management of a patient with CAD are poorly defined. This state-of-the-art review provides an overview of the available evidence on functional patterns of CAD with a special focus on their diagnostic and therapeutic implications. It also aims to provide clear definitions of physiological patterns of CAD based on the available evidence and expert opinion. A practical algorithm is provided to optimize the use of pressure wire and angiography-derived indexes of coronary physiology in the settings of focal, serial, and diffuse lesions, with the addition of intracoronary imaging in selected cases.

Comparative Prognostic Value of Parameters of Pulsatile Right Ventricular Afterload in Patients With Advanced Heart Failure Awaiting Heart Transplantation.

Right ventricular pulsatile afterload (RVPA) demonstrated a strong impact on survival of patients with advanced heart failure (HF) with reduced ejection fraction. The best prognostic parameter of RVPA is unknown. The aim of this work was to examine the prognostic relevance of pulmonary artery compliance (PAC), pulmonary artery elastance (PAE), and pulmonary artery pulsatile index (PAPi) in a consecutive cohort of patients with advanced HF evaluated for heart transplantation (HT). A total of 149 patients with end-stage HF underwent right-sided cardiac catheterization and were clinically followed up until death or any censoring events, including HT, left ventricular assist device, and hospitalization for acute HF. The primary endpoint occurred in 29 patients (19.5%) during a median follow-up time of 12 (interquartile range 3 to 34) months. This cohort presented a worse hemodynamic profile than event-free survivors. PAC <1.9 mL/mm Hg (hazard ratio 3, 95% confidence interval 1.3 to 6.0, p= 0.007) and PAE >0.9 mmHg/mL (hazard ratio 2.5, 95% confidence interval 1.1 to 5.2, p= 0.02) were associated with the adverse outcome. On the contrary, PAPi was not associated with the outcome. PAC demonstrated a superior predictive value for the composite adverse outcome compared with pulmonary vascular resistance (area under the curve comparison p= 0.019) and PAPi (p= 0.03) but similar compared with PAE (p= 0.19) and mean pulmonary arterial pressure (p= 0.51). PAC, but not PAE, showed incremental prognostic value compared with cardiac index (p= 0.02). In conclusion, hemodynamic indexes of RVPA are associated with worse survival in patients with end-stage HF. PAC and PAE demonstrated superior prognostic value compared with PAPi and pulmonary vascular resistance. Moreover, PAC showed incremental prognostic value compared with cardiac index in patients awaiting HT.

Takotsubo Syndrome during COVID-19 Pandemic in the Veneto Region, Italy.

Background: During the COVID-19 pandemic, the risk of SARS-CoV-2 infection, the public health measures of social distancing, the freedom limitations, quarantine, and the enforced homeworking under the lockdown period, as well as medical causes including COVID-19 infection per se, may have caused major emotional distress, especially in the most vulnerable patients. We aimed to evaluate the variations in the number of admissions due to Takotsubo syndrome (TTS) during the COVID-19 pandemic in the Veneto region. Methods: We retrospectively reviewed and analyzed the number of admissions because of TTS in 13 Divisions of Cardiology located in the Veneto region, the northeastern area of Italy, covering a population of more than 2.5 million inhabitants, during the two major pandemic waves of COVID-19 (the first between 15 March and 30 April 2020 and the second between 15 November and 30 December 2020) that occurred in 2020. Results: In total, 807 acute coronary syndromes were admitted in the 13 enrolling hospitals. Among these, 3.9% had TTS. Compared to the corresponding 2018 and 2019 time periods, we observed a significant increase in the number of TTS cases (+15.6%, p = 0.03 and +12.5%, p = 0.04, comparing 2018 to 2020 and 2019 to 2020, respectively). Geographical distribution of the TTS cases reflected the broad spread of the SARS-CoV-2 infection with a significant direct relationship between TTS incidence and the number of COVID-19 infections according to Pearson's correlation (r = 0.798, p < 0.001). Conclusions: The higher incidence of TTS during the 2020 COVID-19 pandemic waves, especially in the areas that were hit hardest in terms of morbidity and mortality by the SARS-CoV-2 infection, suggest a strong direct and/or indirect role of COVID-19 in the pathogenesis of TTS.

Optimal timing for percutaneous coronary intervention in patients undergoing transcatheter aortic valve implantation.

BACKGROUND: The best timing to perform percutaneous coronary interventions (PCI) in patients undergoing TAVI is unknown. Most PCI are performed before TAVI, because of concerns about potential ischemic complications during valve implantation. In this study we aimed to compare short-and long-term outcomes of patients undergoing PCI before or after TAVI. METHODS: Patients undergoing TAVI and PCI from 2010 to 2021 were analyzed. PCI was defined as high-risk when involving unprotected left main, proximal left anterior descending, proximal dominant right coronary artery or 3-vessel disease. The primary endpoint was the cumulative incidence of any TAVI procedural complication and in-hospital adverse events (VARC-3 criteria). RESULTS: Out of 1162 patients, 144 underwent PCI, 68% after TAVI, 78.4% of which were at high-risk. The primary endpoint occurred in 28.4% of patients in PCI pre-TAVI group vs 21.4% in PCI post-TAVI group (p = 0.403) and in 34.4% vs 17.3% of patients respectively among high-risk patients (p = 0.075). A higher rate of stroke was observed in the PCI pre-TAVI group regardless of the PCI complexity (6.5% vs 0.0%, p = 0.031; 9.3% vs 0.0% p = 0.025 in the high-risk group). At 24 months, MACCE-free survival was lower in patients who underwent PCI before TAVI (84.4% vs 97.9%, adjusted HR 10.16, 95% CI 1.19-86.57, p = 0.019; and 84.4% vs 97.3%, adjusted HR 7.34 95% CI 0.78-62.28 p = 0.082 in the high-risk group). CONCLUSIONS: PCI performed after TAVI does not expose patients to higher risks of peri-procedural hazards and provides a trend towards favourable clinical outcome at mid-to-long term.

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.

Incomplete Functional Revascularization Is Associated With Adverse Clinical Outcomes After Transcatheter Aortic Valve Implantation.

BACKGROUND AND PURPOSE: Whether incomplete functional revascularization has an impact on the clinical outcome of patients treated with transcatheter aortic valve implantation (TAVI) is still unknown. We aim to assess the prognostic value of residual functional SYNTAX score (rFSS) in a cohort of patients undergoing TAVI. METHODS AND RESULTS: One-hundred-twenty-four patients (229 lesions) with severe aortic stenosis and coronary artery disease (CAD) underwent fractional flow reserve (FFR)-guided revascularization. The primary endpoint of the study was the composite of cardiac death, myocardial infarction, and revascularization at the last available follow-up after TAVI. Median SYNTAX score (SS) and Functional SYNTAX score (FSS) at baseline were 7 (range 5-12) and 0 (range 0-7) respectively. After revascularization or deferral according to FFR, residual SS (rSS) and rFSS were 5 (range 0-8) and 0 (range 0-0) respectively. Angiographic incomplete revascularization (rSS > 0) was not associated with the primary endpoint (HR 1.2; 95% CI 0.4-3.9; p = 0.69), whereas functional incomplete revascularization (rFSS>0) was associated with worse event-free survival at follow up after adjusting for clinical confounders (HR 3.7; 95% CI 1.0-13.7; p = 0.04). CONCLUSION: Incomplete functional revascularization is associated with adverse clinical outcomes after TAVI. Residual functional SYNTAX score may be regarded as a treatment goal for patients with CAD undergoing TAVI. Further studies are warranted to confirm our hypothesis.

Prognostic impact of antiplatelet therapy in Takotsubo syndrome: a systematic review and meta-analysis of the literature.

While the most recent evidence suggests a lack of benefit, antithrombotic therapy is still extensively prescribed in patients with Takotsubo syndrome (TTS). The objective of this study was to determine whether patients with TTS benefit from anti-aggregation, in terms of either short-term or long-term outcomes. A systematic review and meta-analysis was conducted. A comprehensive search of the literature included MEDLINE, Cochrane Library, Clinicaltrials.gov, EU Clinical Trial Register, References, and contact with the authors. Methodological quality assessment and data extraction were systematically performed. The review adhered to the PRISMA framework guidelines. A total of 86 citations were identified, six being eligible for inclusion, for a total of 1997 patients. One of them considered both short-term and long-term outcomes. One reported outcomes during the index event, while the remaining four focused on potential long-term benefits. They were all retrospective cohort studies.Based on our data, the long-term use of antiplatelet therapy (AT) led to a significantly higher incidence of the composite outcome (OR: 1.54; 95% CI 1.09-2.17; p = 0.014) and overall mortality (OR 1.72; 95% CI 1.07-2.77; p = 0.027). The analysis did not show a statistically significant difference in TTS recurrences, stroke/TIA, and MI or CAD worsening with AT compared with no anti-aggregation. The AT in this settings did not show any clear benefit in improving the long-term outcomes, and it may be even detrimental and it may be detrimental. These results warrant further future research and the design of adequately powered randomized controlled trials focusing on the impact of aspirin on the outcomes in patients presenting with TTS.

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.

Contrast-Induced Nephropathy in Patients Undergoing Staged Versus Concomitant Transcatheter Aortic Valve Implantation and Coronary Procedures.

Background The impact of staged versus concomitant coronary procedures on renal function in patients with aortic stenosis undergoing transcatheter aortic valve implantation (TAVI) remains unclear. Methods and Results Three-hundred thirty-nine patients undergoing coronary procedures and TAVI as a staged strategy (160, 47.2%) or concomitant strategy (179, 52.8%) were retrospectively analyzed. Contrast-induced acute kidney injury (CI-AKI) occurred in 49 patients in the staged strategy group (30.6%) and in 18 patients (10.1%) in the concomitant strategy group (P<0.001). Among the staged strategy group, 25 (15.6%) patients developed CI-AKI after coronary angiography or percutaneous coronary intervention, 17 (10.6%) after TAVI, and 7 (4.3%) after both the procedures. Staged strategy was associated with a higher risk of CI-AKI (odds ratio, 3.948; P<0.001) after adjustment for multiple confounders and regardless of the baseline renal function (P for interaction=0.4) when compared with the concomitant strategy. At a median follow-up of 24.0 months (3.0-35.3), CI-AKI was not associated with sustained renal injury (P=0.794), irrespective of the adopted strategy. The concomitant strategy did not impact the overall early safety at 30 days follow-up after TAVI compared to the staged strategy (P=0.609). Conclusions Performing coronary procedures with a staged strategy before TAVI was associated with a higher risk of CI-AKI compared with a concomitant strategy. Moreover, a concomitant strategy did not increase the risk of procedure-related complications.

Real World Performance Evaluation of Transcatheter Aortic Valve Implantation.

BACKGROUND: The aim of this research is to describe the performance over time of transcatheter aortic valve implantations (TAVIs) in a high-volume center with a contemporary, real-world population. METHODS: Patients referred for TAVIs at the University Hospital of Verona were prospectively enrolled. By cumulative sum failures analysis (CUSUM), procedural-control curves for standardized combined endpoints-as defined by the Valve Academic Research Consortium-2 (VARC-2)-were calculated and analyzed over time. Acceptable and unacceptable limits were derived from recent studies on TAVI in intermediate and low-risk patients to fit the higher required standards for current indications. RESULTS: A total of 910 patients were included. Baseline risk scores significantly reduced over time. Complete procedural control was obtained after approximately 125 and 190 cases for device success and early safety standardized combined endpoints, respectively. High risk patients (STS ≥ 8) had poorer outcomes, especially in terms of VARC-2 clinical efficacy, and required a higher case load to maintain in-control and proficient procedures. Clinically relevant single endpoints were all influenced by operator's experience as well. CONCLUSIONS: Quality-control analysis for contemporary TAVI interventions based on standardized endpoints suggests the need for relevant operator's experience to achieve and maintain optimal clinical results, especially in higher-risk subjects.