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.

A randomised multicentre study of angiography- versus physiologyguided percutaneous coronary intervention in patients with coronary artery disease undergoing TAVI: design and rationale of the FAITAVI trial.

The treatment of coronary artery disease (CAD) in patients with severe aortic valve stenosis (AVS) eligible for transcatheter aortic valve implantation (TAVI) is not supported by clinical evidence, and the role of physiology over anatomy as well as the timing of coronary intervention are not defined. FAITAVI (ClinicalTrials.gov: NCT03360591) is a nationwide prospective, open-label, multicentre, randomised controlled study comparing the angiography-guided versus the physiology-guided coronary revascularisation strategy in patients with combined significant CAD and severe AVS undergoing TAVI. Significant CAD will be defined as coronary stenosis ≥50%, as assessed by visual estimation in vessels ≥2.5 mm. Physiology will be tested by fractional flow reserve (FFR) and instantaneous wave-free ratio (iFR). The study will be conducted at 15 sites in Italy. In the angiography arm, percutaneous coronary intervention (PCI) will be performed either before TAVI, during the TAVI procedure - before or after the valve implantation - or within 1 month±5 days of the valve implantation, left to the operator's decision. In the physiology arm, FFR and iFR will be performed before TAVI, and PCI will be indicated for FFR ≤0.80, otherwise the intervention will be deferred. In case of borderline values (0.81-0.85), FFR and iFR will be repeated after TAVI, with PCI performed when needed. With a sample size of 320 patients, the study is powered to evaluate the primary endpoint (a composite of death, myocardial infarction, stroke, major bleeding, or ischaemia-driven target vessel revascularisation). TAVI indication, strategy and medical treatment will be the same in both groups. After discharge, patients will be contacted at 1, 6, 12 and 24 months after the procedure to assess their general clinical status, and at 12 months for the occurrence of events included in the primary and secondary endpoints. FAITAVI is the first randomised clinical trial to investigate "optimal" percutaneous coronary intervention associated with TAVI in patients with severe AVS and CAD.

Ten-Year Experience with Endomyocardial Biopsy after Orthotopic Heart Transplantation: Comparison between Trans-Jugular and Trans-Femoral Approach.

BACKGROUND: Endomyocardial biopsy (EMB) is considered the gold standard for monitoring allograft rejection after heart transplantation. EMB is an invasive procedure that may be performed via a trans-jugular or a trans-femoral approach with a complication rate reported as less than 6%. The aim of this study was to evaluate the complication rate after EMBs in heart recipients and to compare the results of EMBs performed via a trans-jugular or a trans-femoral approach. METHODS: Medical records of heart recipients undergoing EMBs between January 2012 and December 2022 were retrospectively reviewed. EMB-related complications were classified as major (death, pericardial effusion, hemopericardium, cardiac tamponade requiring a pericardiocentesis or an urgent cardiac surgery, ventricular arrythmias, permanent atrio-ventricular block requiring permanent pacing, hemothorax, pneumothorax and retroperitoneal bleeding) and minor (de novo tricuspid regurgitation, arrhythmias, coronary artery fistula, vascular access site complications). RESULTS: A total of 1698 EMBs were performed during the study period at our institution in 212 heart recipients. There were 927 (55%) EMBs performed through a trans-jugular approach (TJ group) and 771 (45%) EMBs performed through a trans-femoral approach (TF group). A total of 60 (3.5%) complications were recorded, including nine (0.5%) major complications (six cardiac tamponades, two pneumothorax and one retroperitoneal bleeding) and 51 (3%) minor complications (seven coronary fistulae, five de novo tricuspid regurgitation, four supraventricular arrythmias and thirty-five vascular access site complications). No difference was found in total (38 [4%] vs. 22 [3%]; p = 0.16) and major (6 [1%} vs. 3 [0.4%]; p = 0.65) complications (32 [3%] vs. 19 [2%]; p = 0.23) between the TJ group and the TF group. No difference was found in male sex, age at time of EMB and time from HT between complicated and not complicated EMBs. CONCLUSIONS: EMBs represent a safe procedure with a low risk of complications. In our experience, EMBs performed via a trans-jugular approach are as safe as the trans-femoral approach.

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.

Safety and efficacy of everolimus-eluting bioresorbable vascular scaffold for cardiac allograft vasculopathy (CART).

BACKGROUND: Cardiac allograft vasculopathy (CAV) is still the main drawback of heart transplantation (HTx) and percutaneous coronary intervention (PCI) is a palliative measure because of the high incidence of failure. OBJECTIVE: This study aimed to investigate the safety and efficacy of bioresorbable scaffolds (BRSs) as potential novel therapeutic tool for the treatment of coronary stenoses in CAV. METHODS: This is a multicenter, single-arm, prospective, open-label study (CART, NCT02377648), that included patients affected by advanced CAV treated with PCI and second-generation ABSORB BRS (Abbott Vascular). The primary endpoint was the incidence of 12-month angiographic in-segment scaffold restenosis (ISSR). Secondary endpoints were the incidence of major adverse cardiac events (MACEs) at 12- and 36-month follow-up and the incidence of ISSR at 36 months. A paired intracoronary imaging analysis at baseline and follow-up was also performed. RESULTS: Between 2015 and 2017 35 HTx patients were enrolled and treated for 44 coronary lesions with 51 BRSs. The primary endpoint occurred in 13.5% of the lesions (5/37), with a cumulative ISSR rate up to 3 years of 16.2% (6/37). Angiographic lumen loss was 0.40 ± 0.62 mm at 12 months and 0.53 ± 0.57 mm at 36 months. Overall survival rate was 91.4% and 74.3%, and MACEs incidence 14.2% and 31.4% at 12 and 36 months, respectively. At the paired intracoronary imaging analysis, a significant increase of the vessel external elastic membrane area in the treated segment and some progression of CAV proximally to the BRS were detected. CONCLUSIONS: BRS-based PCI for the treatment of CAV is feasible and safe, with an ISSR incidence similar to what reported in retrospective studies with drug-eluting stents.

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.

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.

Integrated Assessment of Computational Coronary Physiology From a Single Angiographic View in Patients Undergoing TAVI.

BACKGROUND: Angiography-derived computational physiology is an appealing alternative to pressure-wire coronary physiology assessment. However, little is known about its reliability in the setting of severe aortic stenosis. This study sought to provide an integrated assessment of epicardial and microvascular coronary circulation by means of single-view angiography-derived physiology in patients with severe aortic stenosis undergoing transcatheter aortic valve implantation (TAVI). METHODS: Pre-TAVI angiographic projections of 198 stenotic coronary arteries (123 patients) were analyzed by means of Murray's law-based quantitative flow ratio and angiography microvascular resistance. Wire-based reference measurements were available for comparison: fractional flow reserve (FFR) in all cases, instantaneous wave-free ratio in 148, and index of microvascular resistance in 42 arteries. RESULTS: No difference in terms of the number of ischemia-causing stenoses was detected between FFR ≤0.80 and Murray's law-based quantitative flow ratio ≤0.80 (19.7% versus 19.2%; P=0.899), while this was significantly higher when instantaneous wave-free ratio ≤0.89 (44.6%; P=0.001) was used. The accuracy of Murray's law-based quantitative flow ratio ≤0.80 in predicting pre-TAVI FFR ≤0.80 was significantly higher than the accuracy of instantaneous wave-free ratio ≤0.89 (93.4% versus 77.0%; P=0.001), driven by a higher positive predictive value (86.9% versus 50%). Similar findings were observed when considering post-TAVI FFR ≤0.80 as reference. In 82 cases with post-TAVI angiographic projections, Murray's law-based quantitative flow ratio values remained stable, with a low rate of reclassification of stenosis significance (9.9%), similar to FFR and instantaneous wave-free ratio. Angiography microvascular resistance demonstrated a significant correlation (Rho=0.458; P=0.002) with index of microvascular resistance, showing an area under the curve of 0.887 (95% CI, 0.752-0.964) in predicting index of microvascular resistance ≥25. CONCLUSIONS: Angiography-derived physiology provides a valid, reliable, and systematic assessment of the coronary circulation in a complex scenario, such as severe aortic stenosis.

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.

Quality of Life after Transcatheter Aortic Valve Replacement in Sarcopenic Patients Using the Toronto Aortic Stenosis Quality of Life Questionnaire.

BACKGROUND: Sarcopenia is the core component of frailty; however, its role in patients undergoing transcatheter aortic valve replacement (TAVR) is a matter of debate. The Toronto Aortic Stenosis Quality of Life Questionnaire (TASQ) is a validated instrument for assessing quality of life (QoL) in patients with severe aortic stenosis (AS). AIMS: We aim to evaluate the QoL of sarcopenic and non-sarcopenic patients with severe AS undergoing TAVR. METHODS: TASQ was prospectively administered to patients undergoing TAVR. All patients completed the TASQ before TAVR and at a 3-month follow-up. The study population was divided in two groups according to sarcopenic status. The primary endpoint was the TASQ score in the sarcopenic and non-sarcopenic cohorts. RESULTS: In total, 99 patients were eligible for the analysis. In both sarcopenic (n = 56) and non-sarcopenic (n = 43) cohorts, significant changes were observed in the overall TASQ score and in all but one (i.e., health expectations) of the individual domains (p < 0.01). Sarcopenic and non-sarcopenic patients showed substantial improvements across TASQ subscores. The mean change in overall TASQ score at three months revealed a significant improvement in both cohorts (p < 0.01). Health expectations worsened in sarcopenic patients at the 3-month follow-up (p = 0.06). CONCLUSIONS: The TASQ questionnaire revealed changes in QoL after TAVR, regardless of patients' sarcopenic status. Health status improved substantially in both sarcopenic and non-sarcopenic patients following TAVR. Lack of improvement in health expectations seems to depend on patients' expectations regarding the procedure and specific aspects in the evaluation of the outcome.

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.

Radial artery occlusion after transradial procedures: impact on 1-year adverse events.

BACKGROUND: Radial artery occlusion after transradial procedures is a frequent iatrogenic thrombotic process. The impact on prognosis has not been investigated. This study sought to investigate whether radial artery occlusion is related to increased risk of major adverse cardiac and cerebrovascular events, defined as death, myocardial infarction, stroke and coronary revascularization. METHODS: Eight hundred thirty-seven consecutive patients who underwent a transradial coronary procedure had patency of radial artery checked at 24 hours. Radial artery occlusion occurred in 41 over 837 patients (4.8%); 764 (91.2%) were available for planned follow-up at 1 year and were included in the analysis. Event-free survival rate between patients with and without radial artery occlusion was calculated using Kaplan-Meier estimates, and Cox proportional-hazards models were used to identify independent risk factors. RESULTS: At a median 370-day follow-up (IQR: 366-375 days), adverse events occurred in 37 patients (4.8%), 2 in patients with radial artery occlusion and 35 in patients without. One-year survival rate was 94.9% vs. 95% (unadjusted HR=1.026, 95% CI: 0.24 to 4.6, P=0.9). After multivariable modeling, age and coronary artery disease extension was associated with increased risk of adverse events. CONCLUSIONS: Age and coronary artery disease extension were independent predictors of adverse events at follow-up. RAO had no prognostic impact.

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.

Predictors and Prognostic Impact of Left Ventricular Ejection Fraction Recovery after Impella-Supported Percutaneous Coronary Interventions in Acute Myocardial Infarction.

Aim: The aim of our study is to assess the predictors and the prognostic role of left ventricle ejection fraction (LVEF) recovery after Impella-supported percutaneous coronary intervention (PCI) in patients presenting with acute myocardial infarction (AMI). Methods: This retrospective, observational study included patients admitted for AMI who underwent Impella-supported PCI in two Italian high-volume cardiac catheterization laboratories. Only patients who underwent an echocardiographic assessment of left ventricle ejection fraction (LVEF) before the procedure (acute LVEF) and during follow-up (follow-up LVEF) were included in the present analysis. Patients with a baseline LVEF ≥40% were excluded from the present analysis. LVEF recovery was calculated as the difference between follow-up LVEF and acute LVEF. A delta ≥5% was considered significant and was used to define the responder group. Results: From April 2007 to December 2020, 64 consecutive patients were included in our study. A total of 55 patients (86%) received hemodynamic support with Impella 2.5, and 9 patients (14%) with Impella CP. Median LVEF at follow-up was significantly higher compared to baseline (36% (30−42) vs. 30% (24−33), p < 0.001). Based on LVEF recovery, 37 patients (57.8%) were deemed responders. According to multivariate analysis, complete functional revascularization was an independent predictor of a significant EF recovery (OR: 0.159; 95% CI: 0.038−0.668; p = 0.012). At three-year follow-up, lack of LVEF recovery was the only predictor of mortality (HR: 5.315; 95% CI: 1.100−25.676; p = 0.038). Conclusions: Functional complete revascularization is an independent predictor of the recovery of LVEF in patients presenting with AMI who underwent Impella-supported PCI. The recovery of LV function is associated with improved prognosis and could be used to stratify the risk of future events at long-term follow-up.

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.