Long-term clinical outcomes in patients with non-ST-segment Elevation Acute Coronary Syndrome and ST-segment elevation myocardial infarction with thrombolysis in myocardial infarction 0 flow.

Background: Thrombolysis in Myocardial Infarction (TIMI) 0 flow often characterizes ST-segment Elevation Myocardial Infarction (STEMI) patients, but may also feature in non-ST-segment Elevation Acute Coronary Syndrome (NSTE-ACS). Since recanalization usually occurs later in NSTE-ACS patients, the aim of this study was to assess whether patients presenting with NSTE-ACS and TIMI 0 flow have worse clinical outcomes as compared to patients presenting with STEMI and TIMI 0 flow. Methods: A single-center retrospective cohort study was conducted with patients treated for NSTE-ACS and STEMI with TIMI 0 flow at diagnostic angiogram between January 2015 and December 2019. The two patient groups were 1:1 matched using a propensity score logistic regression model. The primary outcome was Major Adverse Cardiac Events (MACE), a composite of all-cause mortality, any myocardial infarction, coronary artery bypass graft, urgent target vessel revascularization or stroke during long term follow-up. Results: The total population consisted of 1255 ACS patients, of which 249 NSTE-ACS and 1006 STEMI patients. After propensity score matching, 234 NSTE-ACS patients were matched with 234 STEMI patients. In this matched population, the mean age was 62.6 (±12.4) years and 75.2 % of the patients was male. The median follow-up time was 3.2 years. MACE rates during follow-up were similar between the two matched groups (HR = 0.84 [95 % CI 0.60 - 1.12] with p = 0.33) with cumulative event-free survival of 63.3 % in the NSTE-ACS group vs 59.3 % in the STEMI group at 6 year follow-up. Conclusion: In this retrospective study, a culprit lesion with TIMI 0 flow has similar clinical outcome in NSTE-ACS and STEMI patients. Further research is warranted to determine optimal the timing of PCI in NSTE-ACS patients with TIMI 0 flow.

Predictors of discordance between fractional flow reserve (FFR) and diastolic pressure ratio (dPR) in intermediate coronary lesions.

Background: Recently, non-hyperemic pressure ratios (NHPRs) have been validated as a reliable alternative to fractional flow reserve (FFR). However, a discordance between FFR and NHPRs is observed in 20-25% of cases. The aim of this study is to evaluate predictors of discordance between FFR and diastolic Pressure ratio (dPR). Methods: PREDICT is a retrospective, single center, investigator-initiated study including 813 patients (1092vessels) who underwent FFR assessment of intermediate coronary lesions (angiographic 30%-80% stenosis). dPR was calculated using individual pressure waveforms and dedicated software. Clinical, angiographic and hemodynamic variables were compared between patients with concordant and discordant FFR and dPR values. Results: Median age was 65 (IQR:59-73) years and 70% were male. Hemodynamically significant lesions, as defined by FFR ≤ 0.80, and dPR ≤ 0.89, were identified in 29.6% and 30.3% of cases, respectively. Overall, FFR and dPR values were discordant in 22.1% patients (17.4% of the vessels). Discordance was related to FFR+/dPR- and FFR-/dPR + in 11.8% and 10.3% of patients, respectively.In case of FFR-dPR discordance, a higher prevalence of left anterior descending arteries lesions was observed (70.5% vs. 53.1%, p < 0.001) and mean values of both FFR and dPR were significantly lower (FFR 0.81 ± 0.05 vs 0.85 ± 0.08, p < 0.001, and dPR 0.89 ± 0.04 vs 0.92 ± 0.08,p < 0.001) as compared to vessels with FFR and dPR concordance. Following multivariable adjustment, dPR delta (defined as the absolute difference between measured dPR to the cut-off value of 0.89) turned out to be the only independent predictor of discordance (OR = 0.74, 95% CI 0.68-0.79, p < 0.001). Conclusion: Our study suggests that FFR-to-dPR discordance occurs in approximately one-fifth of patients. Absolute dPR delta appears to be the only independent predictor of discordance.

Validation of Segmental Post-PCI Physiological Gradients With IVUS-Detected Focal Lesions and Stent Underexpansion.

BACKGROUND: Segmental postpercutaneous coronary intervention (PCI) pressure gradients may detect residual disease and potential targets for optimization. However, universal definitions of relevant segmental gradients are lacking. OBJECTIVES: This study sought to evaluate the diagnostic performance of post-PCI fractional flow reserve (FFR), distal coronary pressure-to-aortic pressure ratio (Pd/Pa), and diastolic pressure ratio (dPR) gradients to detect residual focal lesions and stent underexpansion as observed by intravascular ultrasound (IVUS). METHODS: Patients from the IVUS-guided optimization arm of the FFR REACT (FFR-guided PCI Optimization Directed by High-Definition IVUS Versus Standard of Care) trial with complete IVUS and FFR pullback data were included. Patients with angiographically successful PCI and post-PCI FFR <0.90 underwent FFR, Pd/Pa, and IVUS pullbacks. dPR was calculated offline using dedicated software. Segmental pressure gradients (distal, in stent, and proximal) in segments ≥5 mm were evaluated against IVUS-detected residual disease (distal or proximal focal lesions and stent underexpansion). RESULTS: A total of 139 vessels were included (mean post-PCI FFR: 0.83 ± 0.05, range 0.56-0.89). Focal distal and proximal lesions were detected by IVUS in 23 (17.4%) of 132 and 14 (12.6%) of 111 vessels, respectively, whereas stent underexpansion was present in 86 (61.9%) vessels. Diagnostic ability of segmental FFR gradients to predict IVUS-detected distal and proximal lesions was moderate-to-good (area under the curve [AUC]: 0.69 and 0.84, respectively) and poor to moderate for segmental Pd/Pa and dPR gradients (AUC ranging from 0.58 to 0.69). In-stent gradients had no discriminative ability to detect stent underexpansion (FFR AUC: 0.52; Pd/Pa AUC: 0.54; dPR AUC: 0.55). CONCLUSIONS: In patients with post-PCI FFR <0.90, segmental post-PCI pressure gradients have moderate discriminative ability to identify IVUS-detected focal lesions but no discriminative ability to identify IVUS-detected stent underexpansion.

Culprit lesion plaque characterization and thrombus grading by high-definition intravascular ultrasound in patients with ST-segment elevation myocardial infarction.

BACKGROUND: Dedicated prospective studies investigating high-definition intravascular ultrasound (HD-IVUS)-guided primary percutaneous coronary intervention (PCI) are lacking. The aim of this study was to qualify and quantify culprit lesion plaque characteristics and thrombus using HD-IVUS in patients presenting with ST-segment elevation myocardial infarction (STEMI). METHODS: The SPECTRUM study is a prospective, single-center, observational cohort study investigating the impact of HD-IVUS-guided primary PCI in 200 STEMI patients (NCT05007535). The first 100 study patients with a de novo culprit lesion and a per-protocol mandated preintervention pullback directly after vessel wiring were subject to a predefined imaging analysis. Culprit lesion plaque characteristics and different thrombus types were assessed. An IVUS-derived thrombus score, including a 1-point adjudication for a long total thrombus length, long occlusive thrombus length, and large maximum thrombus angle, was developed to differentiate between low (0-1 points) and high (2-3 points) thrombus burden. Optimal cut-off values were obtained using receiver operating characteristic curves. RESULTS: The mean age was 63.5 (±12.1) years and 69 (69.0%) patients were male. The median culprit lesion length was 33.5 (22.8-38.9) mm. Plaque rupture and convex calcium were appreciated in 48 (48.0%) and 10 (10.0%) patients, respectively. Thrombus was observed in 91 (91.0%) patients (acute thrombus 3.3%; subacute thrombus 100.0%; organized thrombus 22.0%). High IVUS-derived thrombus burden was present in 37/91 (40.7%) patients and was associated with higher rates of impaired final thrombolysis in myocardial infarction flow (grade 0-2) (27.0% vs. 1.9%, p < 0.001). CONCLUSIONS: HD-IVUS in patients presenting with STEMI allows detailed culprit lesion plaque characterization and thrombus grading that may guide tailored PCI.

Optical coherence tomography-derived predictors of stent expansion in calcified lesions.

BACKGROUND: Severe coronary artery calcification is associated with stent underexpansion and subsequent stent failure. AIMS: We aimed to identify optical coherence tomography (OCT)-derived predictors of absolute (minimal stent area [MSA]) and relative stent expansion in calcified lesions. METHODS: This retrospective cohort study included patients who underwent percutaneous coronary intervention (PCI) with OCT assessment before and after stent implantation between May 2008 and April 2022. Pre-PCI OCT was used to assess calcium burden and post-PCI OCT was used to assess absolute and relative stent expansion. RESULTS: A total of 361 lesions in 336 patients were analyzed. Target lesion calcification (defined as OCT-detected maximum calcium angle ≥ 30°) was present in 242 (67.0%) lesions. Following PCI, median MSA was 5.37 mm2 in calcified lesions and 6.24 mm2 in noncalcified lesions (p < 0.001). Median stent expansion was 78% in calcified lesions and 83% in noncalcified lesions (p = 0.325). In the subset of calcified lesions, average stent diameter, preprocedural minimal lumen area, and total calcium length were independent predictors of MSA in multivariable analysis (mean difference 2.69 mm2 /mm2 , 0.52 mm2 /mm, and -0.28 mm2 /5 mm, respectively, all p < 0.001). Total stent length was the only independent predictor of relative stent expansion (mean difference -0.465% per mm, p < 0.001). Calcium angle, thickness, and the presence of nodular calcification were not significantly associated with MSA or stent expansion in multivariable analyses. CONCLUSION: Calcium length appeared to be the most important OCT-derived predictor of MSA, whereas stent expansion was mainly determined by total stent length.

Percutaneous Coronary Intervention Versus Coronary Artery Bypass Grafting in Non-ST-Elevation Coronary Syndromes and Multivessel Disease: A Systematic Review and Meta-Analysis.

There is lack of evidence regarding the optimal revascularization strategy in patients with non-ST-elevation acute coronary syndrome (NSTE-ACS) and multivessel disease (MVD). This systematic review and meta-analysis compares the clinical impact of percutaneous coronary intervention (PCI) with that of coronary artery bypass graft surgery (CABG) in this subset of patients. EMBASE, MEDLINE, and Web of Knowledge were searched for studies including patients with NSTE-ACS and MVD who underwent PCI or CABG up to September 1, 2021. The primary end point of the meta-analysis was all-cause mortality at 1 year. The secondary end points were myocardial infarction (MI), stroke, or repeat revascularization at 1 year. The analysis was conducted using the Mantel-Haenszel random-effects model to calculate the odds ratio (OR) with 95% confidence interval (CI). Four prospective observational studies met the inclusion criteria, including 1,542 patients who underwent CABG and 1,630 patients who underwent PCI. No significant differences were found in terms of all-cause mortality (OR 0.91, 95% CI 0.68 to 1.21, p = 0.51), MI (OR 0.78, 95% CI 0.40 to 1.51, p = 0.46), or stroke (OR 1.54, 95% CI 0.55 to 4.35, p = 0.42) between PCI and CABG. Repeat revascularization was significantly lower in the CABG group (OR 0.21, 95% CI 0.13 to 0.34, p <0.00001). In patients presenting with NSTE-ACS and MVD, 1-year mortality, MI, and stroke were similar between patients treated with either PCI or CABG, but the repeat revascularization rate was higher after PCI.

Vessel fractional flow reserve-based non-culprit lesion reclassification in patients with ST-segment elevation myocardial infarction: Impact on treatment strategy and clinical outcome (FAST STEMI I study).

BACKGROUND: Complete revascularization in patients with ST-segment elevation myocardial (STEMI) improves clinical outcome. Vessel fractional flow reserve (vFFR) has been validated as a non-invasive physiological technology to evaluate hemodynamic lesion significance without need for a dedicated pressure wire or hyperemic agent. This study aimed to assess discordance between vFFR reclassification and treatment strategy in intermediate non-culprit lesions of STEMI patients and to assess the clinical impact of this discordance. METHODS: This was a single-center, retrospective cohort study. From January 2018 to December 2019, consecutive eligible STEMI patients were screened based on the presence of a non-culprit vessel with an intermediate lesion (30-80% angiographic stenosis) feasible for offline vFFR analysis. The primary outcome was the percentage of non-culprit vessels with discordance between vFFR and actual treatment strategy. The secondary outcome was two-year vessel-oriented composite endpoint (VOCE), a composite of vessel-related cardiovascular death, vessel-related myocardial infarction, and target vessel revascularization. RESULTS: A total of 441 patients (598 non-culprit vessels) met the inclusion criteria. Median vFFR was 0.85 (0.73-0.91). Revascularization was performed in 34.4% of vessels. Discordance between vFFR and actual treatment strategy occurred in 126 (21.1%) vessels. Freedom from VOCE was higher for concordant vessels (97.5%) as compared to discordant vessels (90.6%)(p = 0.003), particularly due to higher adverse event rates in discordant vessels with a vFFR ≤0.80 but deferred revascularization. CONCLUSIONS: In STEMI patients with multivessel disease, discordance between vFFR reclassification and treatment strategy was observed in 21.1% of non-culprit vessels with an intermediate lesion and was associated with increased vessel-related adverse events.

Procedural Performance of Ultrathin, Biodegradable Polymer-Coated Stents Versus Durable Polymer-Coated Stents Based on Intracoronary Imaging.

OBJECTIVE: Thinner stent struts might lead to a higher risk of recoil and subsequently a smaller minimal stent area (MSA), which is known to be the strongest predictor of stent failure. We compared procedural performance between an ultrathin-strut biodegradable-polymer sirolimus-eluting stent (BP-SES) and a durable-polymer zotarolimus-eluting stent (DP-ZES) using intracoronary imaging. METHODS: A consecutive cohort of patients underwent percutaneous coronary intervention (PCI) with either BP-SES or DP-ZES in a pseudorandomized fashion between July 2018 and October 2019. In the present subanalysis, we included cases in which post-PCI imaging with intravascular ultrasound (IVUS) or optical coherence tomography (OCT) was performed. The primary endpoint of the study was MSA. Secondary endpoints included percentage stent expansion and presence of residual edge disease, malapposition, tissue protrusion, submedial edge dissections, or edge hematoma. RESULTS: A total of 141 treated lesions (78 BP-SES and 63 DP-ZES) in 127 patients were analyzed. Median age was 69.3 years (interquartile range [IQR], 57.3-75.6) and 74.0% of patients were male. All baseline and procedural characteristics were comparable between both groups. Median MSA was 5.80 mm² (IQR, 4.40-7.24) for BP-SES and 6.35 mm² (IQR, 4.76-8.31) for DP-ZES (P=.15). No significant differences in stent expansion, residual edge disease and presence of malapposition, tissue protrusion, submedial edge dissections, or edge hematomas were found. Stent diameter and stent length were found to be independent predictors of MSA. CONCLUSIONS: No significant differences in MSA were found between lesions treated with BP-SES vs DP-ZES. BP-SES and DP-ZES were comparable in terms of procedural performance.

FFR-Guided PCI Optimization Directed by High-Definition IVUS Versus Standard of Care: The FFR REACT Trial.

BACKGROUND: Post-percutaneous coronary intervention (PCI) fractional flow reserve (FFR) <0.90 is common and has been related to impaired patient outcome. OBJECTIVES: The authors sought to evaluate if PCI optimization directed by intravascular ultrasound (IVUS) in patients with post-PCI FFR <0.90 could improve 1-year target vessel failure (TVF) rates. METHODS: In this single-center, randomized, double-blind trial, patients with a post-PCI FFR <0.90 at the time of angiographically successful PCI were randomized to IVUS-guided optimization or the standard of care (control arm). The primary endpoint was TVF (a composite of cardiac death, spontaneous target vessel myocardial infarction, and clinically driven target vessel revascularization) at 1 year. RESULTS: A total of 291 patients with post-PCI FFR <0.90 were randomized (IVUS-guided optimization arm: n = 145/152 vessels, control arm: n = 146/157 vessels). The mean post-PCI FFR was 0.84 ± 0.05. A total of 104 (68.4%) vessels in the IVUS-guided optimization arm underwent additional optimization including additional stenting (34.9%) or postdilatation only (33.6%), resulting in a mean increase in post-PCI FFR in these vessels from 0.82 ± 0.06 to 0.85 ± 0.05 (P < 0.001) and a post-PCI FFR ≥0.90 in 20% of the vessels. The 1-year TVF rate was comparable between the 2 study arms (IVUS-guided optimization arm: 4.2%, control arm: 4.8%; P = 0.79). There was a trend toward a lower incidence of clinically driven target vessel revascularization in the IVUS-guided optimization arm (0.7% vs. 4.2%, P = 0.06). CONCLUSIONS: IVUS-guided post-PCI FFR optimization significantly improved post-PCI FFR. Because of lower-than-expected event rates, post-PCI FFR optimization did not significantly lower TVF at the 1-year follow-up.

Cardiac Catheterizations in Patients With Acute Coronary Syndrome and Prior Coronary Bypass Surgery: Impact of Native vs Graft vs Absent Culprit Lesions on Clinical Outcomes and Treatment Strategy.

BACKGROUND: In patients with prior coronary artery bypass graft surgery (CABG), acute coronary syndrome (ACS) is not uncommon. This study investigated treatment strategy and compared clinical outcomes for native, graft and absent culprit lesions. METHODS: Single-center retrospective cohort study. From July 2010 to July 2019, 642 consecutive ACS patients with prior CABG were screened for eligibility. The primary endpoint was major adverse cardiovascular events (MACE) at 1 year, a composite of all-cause mortality, myocardial infarction, stroke and ischemia-driven revascularization. RESULTS: A total of 549 patients were included, with 215 (39.2 %) having native culprits, 256 (46.6 %) graft culprits and 78 (14.2 %) no clear culprits. Patients with native culprits were treated with native PCI in 94.0 %, re-CABG in 0.9 % and optimal medical therapy (OMT) in 5.1 %. Patients with graft culprits were treated with native PCI in 14.1 %, graft PCI in 81.2 %, re-CABG in 0.8 % and OMT in 3.9 %. All patients without a clear culprit received OMT. The cumulative incidence of 1-year MACE was 24.7 % for native vs 26.2 % for graft vs 21.8 % for absent culprits. Kaplan-Meier curves did not differ significantly. In patients with graft culprit, no significant difference in 1-year MACE was observed between native PCI and graft PCI (30.6 % vs 25.5 %, p = 0.36). CONCLUSIONS: This retrospective study shows that in ACS patients with prior CABG, MACE occurred frequently and was comparable for native, graft and absent culprits. Native PCI as treatment strategy for patients with a graft culprit was relatively common, with no significant difference in MACE as compared to graft PCI.

Correlation of 3D Quantitative Coronary-Angiography Based Vessel FFR With Diastolic Pressure Ratio: A Single-Center Pooled Analysis of the FAST EXTEND and FAST II Studies.

BACKGROUND: Vessel fractional flow reserve (vFFR) has a high diagnostic accuracy in assessing functional lesion significance compared with FFR. Nonhyperemic pressure ratios (NHPRs) were noninferior to FFR to guide revascularization of intermediate lesions. Therefore, the diagnostic performance of vFFR compared with NHPR warrants interest. AIM: To evaluate the diagnostic performance of vFFR with a generic diastolic pressure ratio (dPR) as a reference. METHODS: The study population was derived from the FAST EXTEND and FAST II studies. Between January 2016 and September 2020, a total of 475 patients were enrolled. RESULTS: Median dPR was 0.92 (interquartile range [IQR], 0.87-0.95), median vFFR was 0.86 (IQR, 0.80-0.90). The sensitivity, specificity, positive and negative predictive values, and diagnostic accuracy of vFFR ≤0.80 for dPR ≤0.89 were 66%, 92%, 79%, 85%, and 84%, respectively. Vessel FFR showed a good agreement with dPR (r=0.68), consistent among specific clinical lesion subsets and a high diagnostic accuracy for dPR ≤0.89 (area under the curve=0.89). Discordance between vFFR and dPR was observed in 78/492 cases (15.6%) and logistic regression analysis did not reveal any clinical, angiographic, or hemodynamic variables associated with vFFR and dPR discordance. CONCLUSION: Vessel FFR shows a good agreement with dPR and a high diagnostic accuracy for dPR ≤0.89.

Tissue characterisation and primary percutaneous coronary intervention guidance using intravascular ultrasound: rationale and design of the SPECTRUM study.

INTRODUCTION: Intravascular ultrasound (IVUS) improves clinical outcome in patients undergoing percutaneous coronary intervention (PCI) but dedicated prospective studies assessing the safety and efficacy of IVUS guidance during primary PCI are lacking. METHODS AND ANALYSIS: The SPECTRUM study is a prospective investigator-initiated single-centre single-arm observational cohort study aiming to enrol 200 patients presenting with ST-segment elevation myocardial infarct undergoing IVUS-guided primary PCI. IVUS will be performed at baseline, postintervention and postoptimisation (if applicable), using a 40-60 MHz high-definition (HD) system. Baseline tissue characterisation includes the morphological description of culprit lesion plaque characteristics and thrombus as assessed with HD-IVUS. The primary endpoint is target vessel failure at 12 months (defined as a composite of cardiac death, target vessel myocardial infarction and clinically driven target vessel revascularisation). The secondary outcome of interest is IVUS-guided optimisation, defined as IVUS-guided additional balloon dilatation or stent placement. Other endpoints include clinical and procedural outcomes along with post-PCI IVUS findings. ETHICS AND DISSEMINATION: The protocol of this study was approved by the Ethics Committee of the Erasmus University Medical Center, Rotterdam, the Netherlands. Written informed consent is obtained from all patients. Study findings will be submitted to international peer-reviewed journals in the field of cardiovascular imaging and interventions and will be presented at international scientific meetings. TRIAL REGISTRATION NUMBER: NCT05007535.

Angiography-Based Fractional Flow Reserve: State of the Art.

PURPOSE OF REVIEW: Three-dimensional quantitative coronary angiography-based methods of fractional flow reserve (FFR) derivation have emerged as an appealing alternative to conventional pressure-wire-based physiological lesion assessment and have the potential to further extend the use of physiology in general. Here, we summarize the current evidence related to angiography-based FFR and perspectives on future developments. RECENT FINDINGS: Growing evidence suggests good diagnostic performance of angiography-based FFR measurements, both in chronic and acute coronary syndromes, as well as in specific lesion subsets, such as long and calcified lesions, left main coronary stenosis, and bifurcations. More recently, promising results on the superiority of angiography-based FFR as compared to angiography-guided PCI have been published. Currently available angiography -FFR indices proved to be an excellent alternative to invasive pressure wire-based FFR. Dedicated prospective outcome data comparing these indices to routine guideline recommended PCI including the use of FFR are eagerly awaited.

Intravascular ultrasound-guided versus coronary angiography-guided percutaneous coronary intervention in patients with acute myocardial infarction: A systematic review and meta-analysis.

BACKGROUND: Intravascular ultrasound (IVUS) can overcome the intrinsic limitations of coronary angiography for lesion assessment and stenting. IVUS improves outcomes of patients presenting with stable or complex coronary artery disease, but dedicated data on the impact of IVUS-guided percutaneous coronary intervention (PCI) in patients with acute myocardial infarction (AMI) remains scarce. METHODS: We systematically searched Embase, MEDLINE, Web of Science Core Collection, Cochrane Central Register of Controlled Trials and Google Scholar for studies that compared clinical outcomes for IVUS- versus angio-guided PCI in patients with AMI. The primary endpoint was all-cause mortality and the secondary endpoint major adverse cardiovascular events (MACE). Mantel-Haenszel random-effects model was used to calculate pooled risk ratios (RR) with 95% confidence intervals (CI). RESULTS: Nine studies (8 observational, 1 RCT) with a total of 838.902 patients (796.953 angio-guided PCI, 41.949 IVUS-guided PCI) were included. In patients with AMI, IVUS-guided PCI was associated with a significantly lower risk of all-cause mortality (pooled RR: 0.70; 95% CI, 0.59-0.82; p < 0.01), MACE (pooled RR: 0.86; 95% CI, 0.74-0.99; p = 0.04) and target vessel revascularization (TVR) (pooled RR: 0.83; 95% CI, 0.73-0.95; p < 0.01). In the subset of patients presenting with ST-segment elevation, IVUS-guided PCI remained associated with a reduced risk for both all-cause mortality (pooled RR: 0.79; 95% CI, 0.66-0.95, p = 0.01) and MACE (pooled RR: 0.86; 95% CI, 0.74-0.99, p = 0.04). CONCLUSIONS: This is the first systematic review and meta-analysis comparing IVUS- versus angio-guided PCI in patients with AMI, showing a beneficial effect of IVUS-guided PCI on all-cause mortality, MACE and TVR. Results of ongoing dedicated prospective studies are needed to confirm these findings.