Invasive Physiological Assessment Research Articles

Impact of preceding acetylcholine provocation testing on following coronary physiological assessment during an interventional diagnostic procedure

BackgroundIntracoronary acetylcholine (ACh) provocation test and coronary physiological assessment are useful interventional diagnostic procedures for evaluating ischemia with no obstructive coronary arteries (INOCA). However, the appropriate sequential order of the diagnostic procedures has been a matter of debate. We investigated the impact of preceding ACh provocation on following coronary physiological assessment. MethodsPatients suspected of INOCA underwent invasive coronary physiological assessment using thermodilution method and were divided into two groups according to the implementation of ACh provocation test. The ACh group was further divided into the positive and negative ACh groups. In the ACh group, intracoronary ACh provocation was performed before the invasive coronary physiological assessment. The main interest of this study was to compare coronary physiological indices among the no ACh, negative ACh, and positive ACh groups. ResultsOf 120 patients, the no ACh, and negative and positive ACh groups included 46 (38.3 %), 36 (30.0 %), and 38 (31.7 %), respectively. Fractional flow reserve was lower in the no ACh group than in the ACh group. Resting mean transit time was significantly longer in the positive ACh group, followed by the no ACh and negative ACh groups (1.22 ± 0.55 vs. 1.00 ± 0.46 vs. 0.74 ± 0.36 s, p < 0.001). Index of microcirculatory resistance and coronary flow reserve did not differ significantly among the three groups. ConclusionsPreceding ACh provocation influenced following physiological assessment, particularly when ACh test was positive. Further studies are warranted to determine which interventional diagnostic procedure, ACh provocation or physiological assessment, should be preceded in the invasive evaluation of INOCA.

Diagnostic accuracy of dynamic stress myocardial ct perfusion as compared with invasive coronary physiology assessment in patients with suspected ISR or CAD progression: results of ADVANTAGE II study

Abstract Funding Acknowledgements Type of funding sources: None. Objectives To compare the diagnostic performance of regadenosone-stress dynamic myocardial perfusion assessed by CT (CTP) as compared with that of coronary CT angiography (CCTA) alone by using invasive fractional flow reserve (FFR) and index of microvascular resistance (IMR) as standard of reference. Background Diagnostic performance of CCTA for in-stent restenosis (ISR) detection is still challenging. Recently, CTP demonstrated additional specificity and diagnostic accuracy over CCTA alone in patients with previous stent implantation and suspected IRS or progression of coronary artery disease (CAD). However, no data are available in this clinical setting on the performance of CTP by using a new technique allowing for a non-invasive adjudication of regional myocardial blood flow (Dynamic CTP) and to assess both macrovascular and microvascular disease status. Methods We enrolled consecutive stable patients with previous coronary stenting referred for invasive quantitative coronary angiography (QCA) for clinical indication. All patients underwent dynamic stress myocardial CTP and rest CTP+CCTA by using a last generation scanner characterized by a 16-cm Z-axis coverage and fast (0.28 sec) gantry rotation time. Invasive FFR and IMR were performed during QCA according to the standard practice. The diagnostic rate and diagnostic accuracy of CCTA and CTP were evaluated in a territory-based analyses vs. FFR, IMR (primary endpoint of the study) and QCA (secundary endpoint). Results In 156 enrolled patients (126 men, mean age 63.1±8.2 years), the diagnostic rate (number of territories interpretable/number of territories evaluated) of CTP was significantly higher than that of CCTA (789/799=98.7% vs. 764/799=95.6%; p = 0.0002). The mean absolute MBF values for ischemic territories (pathological FFR and/or IMR) was significantly lower as compared with those for normal territories (96 ± 32 ml/100 g/min vs. 130 ± 46 ml/100 g/min; p&amp;lt; 0.0001). When FFR was used as gold standard, sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of CTP were higher than those of CCTA (89%, 82.8%, 69.2%, 94.6% and 84.7% vs. 60%, 61.9%, 31.9%, 83.8% and 61.5%, p&amp;lt;0.001, respectively). When IMR was used as gold standard, sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of CTP were higher than those of CCTA (76.5%, 85.9%, 72.2%, 88.4% and 82.9% vs. 48.2%, 63.5%, 33.3%, 76.4% and 59.3%, p&amp;lt;0.01, respectively). When the presence of at least one abnormal physiological parameter among FFR and IMR was used as gold standard, the diagnostic accuracy of CTP was higher than that of CCTA (90.8% vs. 68.1%, p&amp;lt;0.001). The mean ED of the total CCTA/rest CTP/stress CTP was 5.63±4.2 mSv. Conclusion In patients with coronary stents, dynamic CTP significantly improves diagnostic rate and accuracy of CCTA alone in comparison with both FFR and IMR.

Invasive Coronary Physiology in Heart Transplant Recipients: State-of-the-Art Review.

Cardiac allograft vasculopathy is a leading cause of allograft failure and death among heart transplant recipients. Routine coronary angiography and intravascular ultrasound in the early posttransplant period are widely accepted as the current standard-of-care diagnostic modalities. However, many studies have now demonstrated that invasive coronary physiological assessment provides complementary long-term prognostic data and helps identify patients who are at risk of accelerated cardiac allograft vasculopathy and acute rejection.

Coronary Artery Stenosis Evaluation by Angiography-Derived FFR: Validation by Positron Emission Tomography and Invasive Thermodilution

BackgroundFractional flow reserve (FFR) derived from invasive coronary angiography (QFR) is promising for evaluation of intermediate coronary artery stenosis. ObjectivesThe authors aimed to compare the diagnostic performance of QFR and the guideline-recommended invasive FFR using 82Rubidium positron emission tomography (82Rb-PET) myocardial perfusion imaging as reference standard. MethodsThis is a prospective, observational study of symptomatic patients with suspected obstructive coronary artery disease on coronary computed tomography angiography (≥50% diameter stenosis in ≥1 vessel). All patients were referred to 82Rb-PET and invasive coronary angiography with FFR and QFR assessment of all intermediate (30%-90% diameter stenosis) stenoses. Main analyses included a comparison of the ability of QFR and FFR to identify reduced myocardial blood flow (<2 mL/g/min) during vasodilation and/or relative perfusion abnormalities (summed stress score ≥4 in ≥2 adjacent segments). ResultsA total of 250 patients (320 vessels) with indication for invasive physiological assessment were included. The continuous relationship of 82Rb-PET stress myocardial blood flow per 0.10 increase in FFR was +0.14 mL/g/min (95% CI: 0.07-0.21 mL/g/min) and +0.08 mL/g/min (95% CI: 0.02-0.14 mL/g/min) per 0.10 QFR increase. Using 82Rb-PET as reference, QFR and FFR had similar diagnostic performance on both a per-patient level (accuracy: 73%; 95% CI: 67%-79%; vs accuracy: 71%; 95% CI: 64%-78%) and per-vessel level (accuracy: 70%; 95% CI: 64%-75%; vs accuracy: 68%; 95% CI: 62%-73%). The per-vessel feasibility was 84% (95% CI: 80%-88%) for QFR and 88% (95% CI: 85%-92%) for FFR by intention-to-diagnose analysis. ConclusionsWith 82Rb-PET as reference modality, the wire-free QFR solution showed similar diagnostic accuracy as invasive FFR in evaluation of intermediate coronary stenosis. (DAN-NICAD – Danish Study of Non-Invasive Diagnostic Testing in Coronary Artery Disease; NCT02264717)

Coronary X-ray angiography segmentation using Artificial Intelligence: a multicentric validation study of a deep learning model

IntroductionWe previously developed an artificial intelligence (AI) model for automatic coronary angiography (CAG) segmentation, using deep learning. To validate this approach, the model was applied to a new dataset and results are reported.MethodsRetrospective selection of patients undergoing CAG and percutaneous coronary intervention or invasive physiology assessment over a one month period from four centers. A single frame was selected from images containing a lesion with a 50–99% stenosis (visual estimation). Automatic Quantitative Coronary Analysis (QCA) was performed with a validated software. Images were then segmented by the AI model. Lesion diameters, area overlap [based on true positive (TP) and true negative (TN) pixels] and a global segmentation score (GSS – 0 -100 points) - previously developed and published - were measured.Results123 regions of interest from 117 images across 90 patients were included. There were no significant differences between lesion diameter, percentage diameter stenosis and distal border diameter between the original/segmented images. There was a statistically significant albeit minor difference [0,19 mm (0,09–0,28)] regarding proximal border diameter. Overlap accuracy ((TP + TN)/(TP + TN + FP + FN)), sensitivity (TP / (TP + FN)) and Dice Score (2TP / (2TP + FN + FP)) between original/segmented images was 99,9%, 95,1% and 94,8%, respectively. The GSS was 92 (87–96), similar to the previously obtained value in the training dataset.Conclusionthe AI model was capable of accurate CAG segmentation across multiple performance metrics, when applied to a multicentric validation dataset. This paves the way for future research on its clinical uses.

Positive Nuclear Stress Test After STEMI: Importance of Invasive Physiologic Assessment and Acetylcholine Testing

Positive Nuclear Stress Test After STEMI: Importance of Invasive Physiologic Assessment and Acetylcholine Testing

Outcomes of deferred revascularisation following negative fractional flow reserve in diabetic and non-diabetic patients: a meta-analysis

BackgroundFractional Flow Reserve (FFR) is a widely applied invasive physiological assessment, endorsed by major guidelines to aid in the decision to perform or defer revascularisation. While a threshold of > 0.8 has been applied universally, clinical outcomes may be affected by numerous factors, including the presence of diabetes. This meta-analysis aims to investigate the outcomes of diabetic versus non-diabetic patients in whom revascularisation was deferred based on negative FFR.MethodsWe performed a meta-analysis investigating the outcomes of diabetic and non-diabetic patients in whom revascularisation was deferred based on negative FFR. A search was performed on MEDLINE, PubMed and EMBASE, and peer-reviewed studies that reported MACE for diabetic and non-diabetic patients with deferred revascularisation based on FFR > 0.8 were included. The primary end point was MACE.ResultsThe meta-analysis included 7 studies in which 4275 patients had revascularisation deferred based on FFR > 0.8 (1250 diabetic). Follow up occurred over a mean of 3.2 years. Diabetes was associated with a higher odds of MACE (OR = 1.66, 95% CI 1.35–2.04, p = < 0.001), unplanned revascularisation (OR = 1.48, 95% CI 1.06–2.06, p = 0.02), all-cause mortality (OR = 1.74, 95% CI 1.20–2.52, p = 0.004) and cardiovascular mortality (OR = 2.08, 95% CI 1.07–4.05, p = 0.03).ConclusionsFor patients with stable coronary syndromes and deferred revascularisation based on FFR > 0.8, the presence of diabetes portends an increased long-term risk of MACE compared to non-diabetic patients.Trail registration URL: https://www.crd.york.ac.uk/PROSPERO/; Unique identifier: CRD42022367312.

Abnormal physiological findings after FFR-based revascularisation deferral are associated with worse prognosis in women

The prognostic value of abnormal resting Pd/Pa and coronary flow reserve (CFR) after fractional flow reserve (FFR)-guided revascularisation deferral according to sex remains unknown. From the ILIAS Registry composed of 20 hospitals globally from 7 countries, patients with deferred lesions following FFR assessment (FFR > 0.8) were included. (NCT 04485234) The primary clinical endpoint was target vessel failure (TVF) at 2-years follow-up. We included 1392 patients with 1759 vessels (n = 564 women, 31.9%). Although resting Pd/Pa was similar between the sexes (p = 0.116), women had lower CFR than men (2.5 [2.0–3.2] vs. 2.7 [2.1–3.5]; p = 0.004). During a 2-year follow-up period, TVF events occurred in 56 vessels (3.2%). The risk of 2-year TVF was significantly higher in women with low versus high resting Pd/Pa (HR: 9.79; p < 0.001), whereas this trend was not seen in men. (Sex: P-value for interaction = 0.022) Furthermore, resting Pd/Pa provided an incremental prognostic value for 2-year TVF over CFR assessment only in women. After FFR-based revascularisation deferral, low resting Pd/Pa is associated with higher risk of TVF in women, but not in men. The predictive value of Pd/Pa increases when stratified according to CFR values, with significantly high TVF rates in women in whom both indices are concordantly abnormal.Clinical Trial Registration: Inclusive Invasive Physiological Assessment in Angina Syndromes Registry (ILIAS Registry), NCT04485234.

Diagnostic Accuracy Of Dynamic Stress Myocardial Ct Perfusion As Compared With Invasive Coronary Physiology Assessment In Patients With Suspected In-stent Restenosis Or Cad Progression: Results Of Advantage 2 Study

Diagnostic Accuracy Of Dynamic Stress Myocardial Ct Perfusion As Compared With Invasive Coronary Physiology Assessment In Patients With Suspected In-stent Restenosis Or Cad Progression: Results Of Advantage 2 Study

723 PREDICTORS OF PERCUTANEOUS CORONARY INTERVENTION DERIVED FROM CORONARY CT ANGIOGRAPHY IN PATIENTS WITH CHRONIC CORONARY SYNDROME

Abstract Aims To assess whether quantitative and qualitative plaque features derived from coronary CT angiography (CCTA) could predict subsequent coronary revascularization by percutaneous coronary intervention (PCI) in patients with suspected chronic coronary syndrome (CCS). Methods From April 2019 to October 2020, all consecutive patients with suspected CCS undergoing CCTA and computation of Fractional Flow Reserve derived from CCTA (FFRCT), with consequent referral to coronary angiography and invasive physiological assessment, were included. The FFRCT 3D-model was used to calculate i) FFRCT value, in distal coronary segments where invasive FFR was measured, ii) trans-lesion gradient, defined as the difference in FFRCT units across the lesion derived from CTA, iii) vessel gradient, i.e., the difference in FFRCT units along the vessel. Quantitative and qualitative plaque analysis at CCTA was performed by experienced operators as recommended by current guidelines. Results Overall, 108 patients (143 vessels) were included. The mean age was 65±8.6 years, and 11% were diabetics. At baseline, 87 (80%) patients had chest pain. Left ventricular ejection fraction was 59±4.6%. Sixty (55.5%) patients underwent PCI, 8 (7.5%) were treated with coronary artery bypass graft (CABG), and 40 (37%) were referred to medical therapy (MT). At CCTA, the lesions undergoing PCI were significantly longer (38.85±17mm, p&amp;lt;0.001), with more severe diameter stenosis (45.43±16.69, p=0.002), lower minimal lumen area (MLA) (2.30± 1.33mm, p=0.013), higher plaque volume (292.31±158.32mm3, p&amp;lt;0.001), greater fibrous-fatty and necrotic core volume (18.87±20.7 and 14.78±27.42, p&amp;lt;0.001), greater maximum calcium arc in the lesion (108.63±65.9, p&amp;lt;0.001) and lower calcium arc the MLA (88.5±10 p=0.037) than the others referred to CABG/MT. In the PCI group, FFRCT was significantly lower (0.69± 0.11, p&amp;lt;0.001), while trans-lesion and vessel gradients were higher (0.09±0.04 and 0.27±0.10 respectively, p&amp;lt;0.001) than the other groups. On multivariate regression model, corrected for all confounding factors, longer lesions (OR 1.11, CI 1,01-1,21, p=0.022), higher maximum calcium arc (OR 1.02, CI 1.01-1.04, p= 0.007) and lower calcium arc at the MLA (OR 0.99, CI 0.98-0.99, p=0.031) were shown to be independent predictors of referral for PCI. Conclusion Lesion length and calcium arc derived from CCTA predict subsequent revascularization by PCI in patients suspected of CAD.

Validation of pressure-bounded coronary flow reserve using invasive coronary physiologic assessment.

Coronary flow reserve (CFR) represents entire coronary compensatory capacity. While CFR assessment is recommended to identify patients at an increased risk of cardiovascular events and coronary microvascular dysfunction, invasive CFR measurement is often technically challenging. Although not well validated yet, pressure-bounded CFR (pbCFR) has been proposed as a simple surrogate to estimate impaired CFR. In this study, we evaluated coronary physiological characteristics of low pbCFR using detailed invasive assessment. Invasive physiological assessment including resting ratio of distal coronary pressure to aortic pressure (Pd/Pa), fractional flow reserve (FFR), resting and hyperemic mean transit time, index of microcirculatory resistance (IMR), CFR, resistive reserve ratio, and microvascular resistance reserve (MRR) was performed in 107 patients in the left anterior descending coronary artery. pbCFR was calculated only with resting Pd/Pa and FFR. Patients were divided into low pbCFR and non-low pbCFR groups. Of 107 patients, 50 (46.7%) had low pbCFR. FFR (0.90 ± 0.05 vs. 0.83 ± 0.05, p < 0.001), hyperemic mean transit time (0.27 ± 0.17 vs. 0.21 ± 0.12, p = 0.04), and IMR (20.4 ± 13.2 vs. 15.0 ± 9.1, p = 0.01) were significantly higher in the low pbCFR group than their counterpart. While directly measured CFR did not differ significantly (4.4 ± 2.3 vs. 5.1 ± 2.8, p = 0.18), MRR was lower in the low pbCFR group (5.4 ± 3.0 vs. 6.8 ± 3.8, p = 0.047). The rates of CFR < 2.0 and IMR ≥ 25 were not significantly different between the 2 groups. In conclusion, although CFR did not differ significantly, IMR and MRR were impaired in patients with low pbCFR, suggesting pbCFR as a potential surrogate of coronary microvascular function in clinical practice.

Combined use of hyperemic and non-hyperemic pressure ratios for revascularization decision-making: From the ILIAS registry

ObjectiveThe aim of this study is to evaluate the diagnostic and prognostic value of non-hyperaemic Pd/Pa and to determine its additional value when combined with the gold standard hyperaemic pressure ratio (FFR) to guide revascularization. MethodsIn a large, multi-center, retrospective registry, we included a total of 2141 patients with a clinical indication for coronary angiography providing physiological data in 2726 vessels. A classification was made based on the FFR (cut-off value: 0.80) and non-hyperaemic Pd/Pa (cut-off value: 0.92) values and the primary outcome was target-vessel failure (TVF) at 5-year follow-up. ResultsMean age was 63 ± 10.0 and 75% of the study population were men. Regression analysis showed an overall good correlation between FFR and non-hyperaemic Pd/Pa (r = 0.73, p < 0.005) and discordance was present in 17% of the vessels. Resting Pd/Pa was independently associated with TVF at 5-year follow-up (HR 0.08, 95%CI: 0.02–0.27; p < 0.005). The risk for TVF was the lowest in vessles with concordant normal pressure ratio's, with the highest risk in vessels with any abnormal pressure ratio in which revascularization was deferred. In these vessels, there was no difference in risk for TVF between the discordant and concordant abnormal values. ConclusionAbnormal pressure ratios in both non-hyperemic and hyperemic conditions portend important prognostic value. Combined application of FFR and non-hyperemic Pd/Pa efficiently identifies those vessels with concordant normal resting and hyperemic pressure ratios of which long-term clinical outcomes are excellent. These data lead to hypothesize that the decision to defer revascularization should potentially be based on combined non-hyperemic and hyperemic pressure ratios. Clinical trial registrationInclusive Invasive Physiological Assessment in Angina Syndromes Registry (ILIAS Registry), NCT04485234

Differential impact of coronary revascularization on long-term clinical outcome according to coronary flow characteristics: analysis of the international ILIAS registry

Abstract Backgrounds Coronary pressure indices such as fractional flow reserve (FFR) are standard in guiding elective revascularization. However, considering additional coronary flow parameters could further individualize and optimize the decision on revascularization, especially in terms of the impact on prognosis. We aimed to investigate the potentially differential prognostic associations of elective PCI according to coronary flow properties represented by coronary flow reserve (CFR), coronary flow capacity (CFC) and baseline CFC (bCFC). Methods From the Inclusive invasive physiological assessment in angina syndromes (ILIAS) registry composed of 16 hospitals globally from 7 countries, patients with obstructive coronary artery disease who underwent invasive coronary physiological assessment were included (N=2370 vessels). We assessed effect measure modifications of the association of PCI and 5-year target vessel failure (TVF) according to CFR, CFC and bCFC either assessed by Doppler-technique or thermodilution-method in three models: conditional logistic regression, marginal structural model, and COX proportional hazard model. Reduced CFR, CFC and bCFC were defined as CFR&amp;lt;2.1, CFR&amp;lt;2.1 with hyperemic average peak flow velocity (APV)&amp;lt;33.8 cm/s, and CFR&amp;lt;2.1 with baseline APV&amp;gt;17.0 cm/s in Doppler-technique, respectively (Figure 1), and the corresponding percentiles in thermodilution-methods. All models were adjusted for FFR, the interaction between PCI and FFR, and other confounders. Results The mean age of the population was 63.3 years and there were 1322 (73.6%) males. Median FFR was 0.85 and PCI was performed in 600 (25.3%) vessels. Reduced CFR, CFC, and abnormal bCFC were defined in 988 (41.7%), 542 (22.9%), and 600 (25.3%) vessels, respectively. There were little overlaps in vessels with reduced CFC and abnormal bCFC. In univariate analyses, vessels with reduced CFC had worse outcomes compared with those with normal CFC if deferred (13.4% vs. 6.6%), whereas reduced CFC was associated with better prognosis if treated by PCI (9.5% vs. 11.3%). Significant effect measure modifications were observed by CFC either in odds ratio (P=0.0018), additive (P=0.029), and hazard ratio scale (P=0.0002) (Figure 2). Vessels with reduced CFC had, compared with those with normal CFC, higher adjusted absolute risk of 5-year TVF by 5.9 [0.1, 12] percent if deferred, but lower risk by 1.8 [−1.7, 5.3] percent if treated by PCI. CFR and bCFC were not significant effect modifiers in any scales. Similar associations were observed in per-patient analyses, whereas the findings were less robust. Conclusions We observed a beneficial impact of PCI on absolute risk of 5-year clinical outcomes in vessels with reduced CFC, and a detrimental effect in those with normal CFC. CFR and bCFC were not robust effect modifiers of PCI. Therefore, CFC, combined with FFR, could be potentially used to optimize the patient selection for elective PCI treatment. Funding Acknowledgement Type of funding sources: None.

Microvascular dysfunction in patients with diabetes mellitus: assessment of absolute coronary flow and microvascular resistance reserve

Abstract Background Coronary microvascular dysfunction (CMD) is an early feature of diabetic cardiomyopathy, which usually precedes the onset of systolic and diastolic dysfunction (DDF). Continuous intracoronary thermodilution allows an accurate and reproducible assessment of absolute coronary blood flow and microvascular resistance thus allowing the evaluation of coronary flow reserve (CFR) and Microvascular Resistance Reserve (MRR), a novel index specific for microvascular function, which is independent from the myocardial mass. In the present study we compared absolute coronary flow and resistance, CFR and MRR assessed by continuous intracoronary thermodilution in diabetic versus non-diabetic patients. Left atrial reservoir strain (LASr), an early marker of DDF was compared between the two groups. Methods In this observational retrospective study, 108 patients with suspected angina and non-obstructive coronary artery disease (NOCAD) consecutively undergoing elective coronary angiography (CAG) from September 2018 to June 2021 were enrolled. The invasive functional assessment of microvascular function was performed in the left anterior descending artery (LAD) with intracoronary continuous thermodilution. Patients were classified according to the presence of DM. Absolute resting and hyperemic coronary flow (in mL/min) and resistance (in WU) were compared between the two cohorts. FFR was measured to assess coronary epicardial lesions, while CFR and MRR were calculated to assess microvascular function. LAS, assessed by speckle tracking echocardiography, was used to detect early myocardial structural changes potentially associated with microvascular dysfunction. Results The median FFR value was 0.83 [0.79–0.87] without any significant difference between the two groups. Absolute resting and hyperemic flow in the left anterior descending coronary were similar between diabetic and non-diabetic patients. Similarly, resting and hyperemic resistances did not change significantly between the two groups. In the DM cohort the CFR and MRR were significantly lower compared to the control group (CFR=2.4±0.6 and 2.9±0.8; MRR=2.8±0.9 and 3.5±1 for diabetic and non-diabetic patients respectively, [p&amp;lt;0.05 for both], Figure 1 and 2). Likewise, diabetic patients had a significantly lower reservoir, contractile and conductive LAS (all p&amp;lt;0.05). Conclusions Compared with non-diabetic patients, CFR and MRR were lower in patients with DM and non-obstructive epicardial coronary arteries, while both resting and hyperemic coronary flow and resistance were similar. LASr was lower in diabetic patients, confirming the presence of a subclinical DDF associated to the microcirculatory impairment. Continuous intracoronary thermodilution-derived indexes provide a reliable and operator-independent assessment of coronary macro- and microvasculature and might potentially facilitate widespread clinical adoption of invasive physiologic assessment of suspected microvascular disease. Funding Acknowledgement Type of funding sources: None.

The guiding value of hybrid resting full-cycle ratio and fractional flow reserve strategy for percutaneous coronary intervention in a Chinese real-world cohort with non-ST elevation acute coronary syndrome.

ObjectiveThe study aimed to assess the correlation and agreement between resting full-cycle ratio (RFR) and fractional flow reserve (FFR), and evaluate the guiding value of a hybrid RFR-FFR strategy for percutaneous coronary intervention (PCI) in a Chinese real-world cohort with non-ST elevation acute coronary syndrome (NSTE-ACS).Materials and methodsA total of 109 patients with NSTE-ACS (149 diseased vessels), who underwent an invasive physiological assessment in Cangzhou Central Hospital, Hebei Medical University, were prospectively enrolled from September 2021 to May 2022. FFR ≤ 0.80 was used as the gold standard for coronary artery functional ischemia. We utilized the Pearson correlation and Bland-Altman analysis to assess the correlation and agreement between RFR and FFR. The diagnostic value of RFR predicting FFR ≤ 0.80 was evaluated in accordance with the receiver operating characteristic (ROC) curve. The hybrid RFR-FFR strategy, which was established according to determining the “gray zone” of RFR (FFR was further assessed using vasodilators only for diseased vessels in the “gray zone”), needed to afford over 95% global agreement with the FFR-only strategy.ResultsResting full-cycle ratio was significantly linearly linked with FFR (R2 = 0.636, P < 0.001). The accuracy, specificity, and sensitivity for RFR ≤ 0.89 predicting FFR ≤ 0.80 were 81.2, 70.8, and 86.1%, respectively. The area under the ROC curve for RFR predicting FFR ≤ 0.80 was 0.881 (P < 0.001), and the cutoff value was 0.90. The “gray zone” of RFR was 0.85–0.93. The positive and negative predictive values of the hybrid RFR-FFR strategy were 0.95 and 0.93, respectively. The hybrid RFR-FFR strategy exhibited an agreement of 96.0% with FFR and obviated the need for a vasodilator by 60.4%.ConclusionResting full-cycle ratio and FFR have high correlation and consistency. The hybrid RFR-FFR strategy highlights considerably enhanced agreement with the FFR-only strategy, whilst making the requirement of vasodilator administration less than a half.

Safety and effectiveness of post percutaneous coronary intervention physiological assessment: Retrospective data from the post-revascularization optimization and physiological evaluation of intermediate lesions using fractional flow reserve registry.

BackgroundWhile the importance of invasive physiological assessment (IPA) to choose coronary lesions to be treated is ascertained, its role after PCI is less established. We evaluated feasibility and efficacy of Physiology-guided PCI in the everyday practice in a retrospective registry performed in a single high-volume and “physiology-believer” center.Materials and methodsThe PROPHET-FFR study (NCT05056662) patients undergoing an IPA in 2015–2020 were retrospectively enrolled in three groups: Control group comprising patients for whom PCI was deferred based on a IPA; Angiography-Guided PCI group comprising patients undergoing PCI based on an IPA but without a post-PCI IPA; Physiology-guided PCI group comprising patients undergoing PCI based on an IPA and an IPA after PCI, followed by a physiology-guided optimization, if indicated. Optimal result was defined by an FFR value ≥ 0.90.ResultsA total of 1,322 patients with 1,591 lesions were available for the analysis. 893 patients (67.5%) in Control Group, 249 patients (18.8%) in Angiography-guided PCI Group and 180 patients (13.6%) in Physiology-guided PCI group. In 89 patients a suboptimal functional result was achieved that was optimized in 22 cases leading to a “Final FFR” value of 0.90 ± 0.04 in Angiography-Guided PCI group. Procedural time, costs, and rate of complications were similar. At follow up the rate of MACEs for the Physiology-guided PCI group was similar to the Control Group (7.2% vs. 8.2%, p = 0.765) and significantly lower than the Angiography-guided PCI Group (14.9%, p < 0.001), mainly driven by a reduction in TVRs.Conclusion“Physiology-guided PCI” is a feasible strategy with a favorable impact on mid-term prognosis. Prospective studies using a standardized IPA are warrant to confirm these data.

Differential Impact of Coronary Revascularization on Long-Term Clinical Outcome According to Coronary Flow Characteristics: Analysis of the International ILIAS Registry

Coronary pressure indices such as fractional flow reserve are the standard for guiding elective revascularization. However, considering additional coronary flow parameters could further individualize and optimize the decision on revascularization. We aimed to investigate the potentially differential prognostic associations of elective percutaneous coronary intervention (PCI) according to coronary flow properties represented by coronary flow reserve (CFR), coronary flow capacity (CFC), and baseline CFC (bCFC). From the ILIAS Registry (Inclusive Invasive Physiological Assessment in Angina Syndromes) composed of 16 hospitals globally from 7 countries, patients with obstructive coronary artery disease who underwent invasive coronary physiological assessment were included (N=2370 vessels). We assessed effect measure modifications of the association of PCI and 5-year target vessel failure according to CFR, CFC, and bCFC either assessed by Doppler-technique or thermodilution-method. The mean age of the population was 63.3 years, and there were 1322 (73.6%) males. Median fractional flow reserve was 0.85, and PCI was performed in 600 (25.3%) vessels. Reduced CFR, CFC, and abnormal bCFC were defined in 988 (41.7%), 542 (22.9%), and 600 (25.3%) vessels, respectively. Significant effect measure modifications were observed by CFC either in odds ratio (P=0.0018), additive (P=0.029), and hazard ratio scale (P=0.0002). The absolute risk of 5-year target-vessel failure was higher if treated by PCI in vessels with normal CFC by 1.8 (-1.7 to 5.3) percent, while that was lower by -5.9 (-12 to -0.1) percent in those with reduced CFC. CFR and bCFC were not significant effect modifiers in any scales. Similar associations were observed in per-patient analyses, whereas the findings were less robust. We observed qualitative effect measure modification of PCI and 5-year clinical outcomes according to CFC status in additive scale. CFR and bCFC were not robust effect modifiers. Therefore, CFC could be potentially used to optimize the patient selection for elective PCI treatment combined with fractional flow reserve.

D-10 | Procedural Characteristics of Patients with Ischemia and No Obstructive Disease Undergoing Invasive Coronary Physiology Testing

Ischemia and no obstructive coronary artery disease (INOCA) is increasingly recognized and recent guidelines recommend invasive coronary physiology testing for evaluation of chest pain in selected patients. However, this is not routinely performed in clinical practice. We report the procedural characteristics of patients with INOCA who underwent clinically indicated invasive coronary physiology assessment.

Differential Prognostic Value of Revascularization for Coronary Stenosis With Intermediate FFR by Coronary FlowReserve.

The authors sought to evaluate comparative prognosis between deferred versus performed percutaneous coronary intervention (PCI) according to coronary flow reserve (CFR) values of patients with intermediate fractional flow reserve (FFR). For coronary stenosis with intermediate FFR, the prognostic value of PCI remains controversial. The prognostic impact of PCI may be different according to CFR in patients with intermediate FFR. From the ILIAS Registry (Inclusive Invasive Physiological Assessment in Angina Syndromes Registry, N=2,322), 400 patients (412 vessels) with intermediate FFR (0.75-0.80) were selected. Patients were stratified into preserved CFR (>2.0, n=253) and depressed CFR (≤2.0, n=147) cohorts. Per-vessel clinical outcomes during 5 years of follow-up were compared between deferred versus performed PCI groups in both cohorts. The primary outcome was target vessel failure (TVF), a composite of cardiac death, target vessel myocardial infarction, or target vessel revascularization. Among the study population, PCI was deferred for 210 patients (219 vessels, 53.2%) (deferred group) and performed for 190 patients (193 vessels, 46.8%) (performed group). The risk of TVF was comparable between the deferred and performed groups (12.8% vs 14.2%; adjusted HR: 1.403; 95%CI: 0.584-3.369; P=0.448). When stratified by CFR, PCI was performed in 39.1% (100/261 vessels) of the preserved CFR cohort and 61.9% (93/151 vessels) of the depressed CFR cohort. Within the preserved CFR cohort, the risk of TVF did not differ significantly between the deferred and performed groups (11.0% vs 13.9%; adjusted HR: 0.770; 95%CI: 0.262-2.266; P=0.635). However, in the depressed CFR cohort, the deferred group had a significantly higher risk of TVF than the performed group (17.2% vs 14.2%; adjusted HR: 4.932; 95%CI: 1.312-18.53; P=0.018). A significant interaction was observed between CFR and the treatment decision (interaction P =0.049). Results were consistent after inverse probability weighting adjustment. In patients with intermediate FFR of 0.75 to 0.80, the prognostic value of PCI differed according to CFR, with a significant interaction. PCI was associated with a lower risk of TVF compared with the deferral strategy when CFR was depressed (≤2.0), but there was no difference when CFR was preserved (>2.0). CFR could be used as an additional risk stratification tool to determine treatment strategies in patients with intermediate FFR. (Inclusive Invasive Physiological Assessment in Angina Syndromes Registry [ILIAS Registry]; NCT04485234).

Combined Assessment of FFR and CFR for Decision Making in Coronary Revascularization

The aim of this study was to demonstrate the clinical implications of combined assessment of fractional flow reserve (FFR) and coronary flow reserve (CFR).Combined assessment of FFR and CFR allows detailed characterization of pathophysiology in chronic coronary syndromes. Data on the clinical implications of distinct FFR and CFR patterns are limited, leading to uncertainty regarding their relevance.Patients with chronic coronary syndromes and obstructive coronary artery disease were selected from the multicenter ILIAS (Inclusive Invasive Physiological Assessment in Angina Syndromes) registry. Patients were classified into 4 groups on the basis of FFR ≤0.80 and CFR <2.0. The endpoint was the 5-year target vessel failure (TVF) rate.A total of 2,143 patients with 2,725 lesions were included. Compared with normal FFR/normal CFR, low FFR/low CFR carried the highest risk for TVF (HR: 5.4; 95% CI: 3.2-9.3; P < 0.001), significantly higher than in revascularized vessels (P = 0.007). Discordance, with either low FFR/normal CFR or normal FFR/low CFR, was associated with increased TVF rates compared with normal FFR/normal CFR (low FFR/normal CFR: HR: 3.5 [95% CI: 2.2-5.4; P < 0.001]; normal FFR/low CFR: HR: 3.0 [95% CI: 1.9-4.7; P < 0.001]). No difference in 5-year TVF was observed between the 2 discordant groups (P = 0.57) or between the discordant groups and the revascularized group (P = 0.26 vs low FFR/normal CFR; P = 0.60 vs normal FFR/low CFR).Impaired coronary hemodynamics are uniformly associated with increased 5-year TVF rates. Nonrevascularized vessels with discordant FFR and CFR are associated with 5-year event rates that are equivalent to those of vessels that undergo revascularization, whereas vessels with combined low FFR and CFR exhibit event rates that are significantly higher than after revascularization. (Inclusive Invasive Physiological Assessment in Angina Syndromes Registry [ILIAS Registry]; NCT04485234).