Clinical Value of Single-Projection Angiography-Derived FFR in Noninfarct-Related Artery.

BACKGROUND: The Murray law-based quantitative flow ratio (µFR) is an emerging technique that requires only 1 projection of coronary angiography with similar accuracy to quantitative flow ratio (QFR). However, it has not been validated for the evaluation of noninfarct-related artery (non-IRA) in acute myocardial infarction (AMI) settings. Therefore, our study aimed to evaluate the diagnostic accuracy of µFR and the safety of deferring non-IRA lesions with µFR >0.80 in the setting of AMI. METHODS: µFR and QFR were analyzed for non-IRA lesions of patients with AMI enrolled in the FRAME-AMI trial (Fractional Flow Reserve Versus Angiography-Guided Strategy for Management of Non-Infarction Related Artery Stenosis in Patients With Acute Myocardial Infarction), consisting of fractional flow reserve (FFR)-guided percutaneous coronary intervention and angiography-guided percutaneous coronary intervention groups. The diagnostic accuracy of µFR was compared with QFR and FFR. Patients were classified by the non-IRA µFR value of 0.80 as a cutoff value. The primary outcome was a vessel-oriented composite outcome, a composite of cardiac death, non-IRA-related myocardial infarction, and non-IRA-related repeat revascularization. RESULTS: µFR and QFR analyses were feasible in 443 patients (552 lesions). µFR showed acceptable correlation with FFR (R=0.777; P<0.001), comparable C-index with QFR to predict FFR ≤0.80 (µFR versus QFR: 0.926 versus 0.961, P=0.070), and shorter total analysis time (mean, 32.7 versus 186.9 s; P<0.001). Non-IRA with µFR >0.80 and deferred percutaneous coronary intervention had a significantly lower risk of vessel-oriented composite outcome than non-IRA with performed percutaneous coronary intervention (3.4% versus 10.5%; hazard ratio, 0.37 [95% CI, 0.14-0.99]; P=0.048). CONCLUSIONS: In patients with multivessel AMI, µFR of non-IRA showed acceptable diagnostic accuracy comparable to that of QFR to predict FFR ≤0.80. Deferred non-IRA with µFR >0.80 showed a lower risk of vessel-oriented composite outcome than revascularized non-IRA. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02715518.

Multivessel Coronary Function Testing Increases Diagnostic Yield in Patients With Angina and Nonobstructive Coronary Arteries.

BACKGROUND: Invasive CFT is the gold standard for diagnosing coronary vasomotor dysfunction in patients with ANOCA. Most institutions recommend only testing the left coronary circulation. Therefore, it is unknown whether testing multiple coronary territories would increase diagnostic yield. OBJECTIVES: The aim of this study was to evaluate the diagnostic yield of multivessel, compared with single-vessel, invasive coronary function testing (CFT) in patients with angina and nonobstructive coronary arteries (ANOCA). METHODS: Multivessel CFT was systematically performed in patients with suspected ANOCA. Vasoreactivity testing was performed using acetylcholine provocation in the left (20 to 200 µg) and right (20 to 80µg) coronary arteries. A pressure-temperature sensor guidewire was used for coronary physiology assessment in all three epicardial vessels. RESULTS: This multicenter study included a total of 228 vessels from 80 patients (57.8 ± 11.8 years of age, 60% women). Compared with single-vessel CFT, multivessel testing resulted in more patients diagnosed with coronary vasomotor dysfunction (86.3% vs 68.8%; P = 0.0005), coronary artery spasm (60.0% vs 47.5%; P = 0.004), and CMD (62.5% vs 36.3%; P < 0.001). Coronary artery spasm (n = 48) predominated in the left coronary system (n = 38), though isolated right coronary spasm was noted in 20.8% (n = 10). Coronary microvascular dysfunction (CMD), defined by abnormal index of microcirculatory resistance and/or coronary flow reserve, was present 62.5% of the cohort (n = 50). Among the cohort with CMD, 27 patients (33.8%) had 1-vessel CMD, 15 patients (18.8%) had 2-vessel CMD, and 8 patients (10%) had 3-vessel CMD. CMD was observed at a similar rate in the territories supplied by all 3 major coronary vessels (left anterior descending coronary artery = 36.3%, left circumflex coronary artery = 33.8%, right coronary artery = 31.3%; P = 0.486). CONCLUSIONS: Multivessel CFT resulted in an increased diagnostic yield in patients with ANOCA compared with single-vessel testing. The results of this study suggest that multivessel CFT has a role in the management of patients with ANOCA.

Assessment of the Level of Matrix Metalloproteinases, VEGF and MicroRNA-34a in Patients With Non-obstructive and Obstructive Lesions of the Coronary Arteries.

AIM: To assess the levels of matrix metalloproteinases (MMP), vascular endothelial growth factor (VEGF), and miRNA-34a expression in patients with ischemic heart disease (IHD) and obstructive and nonobstructive coronary artery (CA) disease. MATERIAL AND METHODS: This cross-sectional observational study included 64 patients with IHD (diagnosis verified by coronary angiography or multislice computed tomography coronary angiography), of which 33 (51.6%) were men aged 64.9±8.1 years. 20 patients had nonobstructive CA disease (stenosis <50%), and 44 had hemodynamically significant stenoses. The control group consisted of 30 healthy volunteers. MMP-1, -9, -13, and -14, miRNA-34a, and VEGF were measured in all patients. RESULTS: The concentration of MMP-1 was significantly higher in patients with ischemia and nonobstructive CA disease (INOCAD) (p=0.016), and the concentration of MMP-9 was the highest in the group with obstructive CA disease (p<0.001). The concentrations of MMP-13 and MMP-14 did not differ significantly between the groups. The highest VEGF concentrations were observed in the INOCAD group (p<0.001). The expression of miRNA-34a significantly differed between the IHD groups with different types of CA disease and controls (p <0.001). Patients with hemodynamically significant stenosis showed moderate relationships between the concentrations of MMP-14 and VEGF (ρ=0.418; p=0.024), as well as between VEGF and miRNA-34a (ρ=0.425; p=0.022). Patients with INOCAD had a significant negative correlation between the concentrations of MMP-13 and VEGF (ρ= -0.659; p=0.003). Correlation analysis showed in all IHD patients a moderate relationship of the concentrations of MMP-1 and MMP-14 with VEGF (ρ=0.449; p=0.002 and p=0.341; p=0.019, respectively). According to ROC analysis, a MMP-9 concentration above 4.83 ng/ml can be a predictor for the presence of hemodynamically significant CA obstruction in IHD patients; a VEGF concentration higher than 27.23 pg/ml suggests the absence of hemodynamically significant CA stenosis. CONCLUSION: IHD patients with INOCAD had the greatest increase in MMP-1, whereas patients with obstructive CA disease had the highest level of MMP-9. According to our data, concentrations of MMP-9 and VEGF can be used to predict the degree of CA obstruction. The expression of miRNA-34a was significantly higher in IHD patients with INOCAD and CA obstruction than in the control group, which suggested a miRNA-34a contribution to the development and progression of coronary atherosclerosis. In the future, it may be possible to use this miRNA as a diagnostic marker for IHD.

Renal Dysfunction Increases Risk of Adverse Cardiovascular Events in 5-Year Follow-Up Study of Intermediate Coronary Artery Lesions.

BACKGROUND Progression of chronic coronary syndrome (CCS) is influenced by chronic kidney disease (CKD). This 5-year follow-up study aimed to assess 100 patients with 118 intermediate coronary artery lesions evaluated by fractional flow reserve (FFR) and intravascular imaging stratified according to renal function. MATERIAL AND METHODS This prospective study enrolled patients with intermediate coronary stenosis identified by coronary angiogram. Patients with severe renal dysfunction (estimated glomerular filtration rate (eGFR) <45 ml/min/1.73 m²) were excluded from the study. The remaining were divided into 2 groups according to eGFR: 45-60 ml/min/1.73 m² for mild-to-moderate renal dysfunction and >60 ml/min/1.73 m² for no renal dysfunction. We analyzed intermediate-grade stenoses (40-80% as assessed in coronary angiography) with the use of optical coherence tomography (OCT), FFR, and intravascular ultrasound (IVUS). RESULTS Renal dysfunction patients were older (67.7±8.1 vs 63.6±9.7 years, P=0.044). Lesion characteristics, including plaque type and minimal lumen area in OCT, showed no significant differences between the renal dysfunction and no renal dysfunction groups. Thin-cap fibroatheroma, calcific plaques, lipidic plaques, and fibrous plaques had similar prevalence. FFR values and IVUS parameters did not significantly differ between the groups. Over a 5-year follow-up, individuals with mild-to-moderate renal dysfunction had an elevated risk of all-cause mortality and major adverse cardiovascular events in multivariate analyses adjusted for age and sex. CONCLUSIONS Mild-to-moderate renal dysfunction was not associated with significant differences in OCT- and IVUS-derived plaque morphology nor with functional indices characterizing intermediate-grade coronary stenoses. Renal dysfunction was related to a higher risk of all-cause mortality and major adverse cardiovascular events prevalence in 5-year follow-up.

Computed tomography myocardial perfusion imaging to detect myocardial ischemia in patients with anxiety and obstructive coronary heart disease post-exposure to mental stressors.

This study aims to measure myocardial blood flow (MBF) using dynamic CT- myocardial perfusion imaging (CT-MPI) combined with mental stressors in patients with obstructive coronary artery disease (OCAD) and in patients with anxiety and no obstructive coronary artery disease (ANOCAD). A total of 30 patients with OCAD with 30 patients with ANOCAD were included in this analysis. Using the 17-segment model, the rest and stress phase MBF of major coronary arteries in participants were recorded respectively. Compared with ANOCAD patients, OCAD patients were more likely to have localized reduction of MBF (p < 0.05). For patients with ANOCAD, both global MBF and MBF of the main coronary arteries in the stress phase were lower than those in the rest phase (all p < 0.05), but there was no significant difference in MBF among the main coronary arteries in the rest or stress phase (p = 0.25, p = 0.15). For patients with OCAD, the MBF of the target area was lower than that of the non-target area in both the rest and stress phase, and the MBF of the target area in the stress phase was lower than that in the rest phase (all p < 0.05). However, there was no significant difference in MBF between the rest or stress phase in the non-target area (p = 0.73). Under mental stress, the decrease in MBF in ANOCAD patients was diffuse, while the decrease in MBF in OCAD patients was localized. Dynamic CT-MPI combined with mental stressors can be used to detect MBF changes in anxiety patients.

Characteristics of Right-Sided Accessory Pathways Associated With Right Cardiac Veins.

BACKGROUND: The anatomy of myocardial fibers around the right cardiac veins (RCVs) and their roles in accessory pathways (APs) are rarely reported. METHODS: Six RCV-APs were identified from 566 patients with right-sided APs. Mapping of retrograde atrial activation was performed using CARTO 3 system under orthodromic tachycardia or right ventricular pacing. Venography of RCVs was acquired at the earliest retrograde atrial activation. RESULTS: Patients enrolled had a median age of 30 (11-51) years, 5 of them were male. Venography of RCVs could be classified into 3 distinct patterns based on the identified ventricular branches, right marginal vein only (type I; n=3), both right marginal vein and anterior cardiac veins (type II; n=2), and anterior cardiac vein only (type III; n=1). Patients with type I venography had rS QRS pattern in lead V1, negative delta wave in lead III and negative or isoelectric delta wave in lead aVF. However, patients with type II and III venography had QS QRS patterns in lead V1 and variable patterns of delta wave in inferior leads. Earliest retrograde atrial activation was found at a median of 16.75 (14.60-20.00) mm away from the tricuspid annulus, all with A larger than V. At the earliest retrograde atrial activation, far-field ventricular electrogram was found 30 ms later than QRS onset in 1 patient under sinus rhythm. AP conduction was eliminated by mechanical pressure in 2 and by radiofrequency ablation in 4 at the ostium of the veins colocalizing with the earliest retrograde activation of the right atrium. No recurrence was observed during 36 (10-60) months follow-up. CONCLUSIONS: The RCV-AP is a rare form of right-sided APs characterized by atrial insertions distant from the annulus. ECG-speculated ventricular insertion sites conformed to the location of identified RCVs.

Agreement of Fractional Flow Reserve Estimated by Computed Tomography With Invasively Measured Fractional Flow Reserve: A Systematic Review and Meta-Analysis.

BACKGROUND: Fractional flow reserve (FFR) is the ratio of blood pressure measured distal to a stenosis and pressure proximal to a stenosis. FFR can be estimated noninvasively using computed tomography (CT) although the usefulness of this technique remains controversial. This meta-analysis evaluated the agreement of FFR estimated by CT (FFR-CT) with invasively measured FFR. The study also evaluated the diagnostic accuracy of FFR-CT, defined as the ability of FFR-CT to classify lesions as hemodynamically significant (invasive FFR ≤0.8) or insignificant (invasive FFR >0.8). METHODS AND RESULTS: Forty-three studies reporting on 7291 blood vessels from 5236 patients were included. A moderate positive linear relationship between FFR-CT and invasively measured FFR was observed (Spearman correlation coefficient: 0.67). Agreement between the 2 measures increased as invasively measured FFR values approached 1. The overall diagnostic accuracy, sensitivity and specificity of FFR-CT were 82.2%, 80.9%, and 83.1%, respectively. Diagnostic accuracy of 90% could be demonstrated for FFR-CT values >0.90 and <0.49. The diagnostic accuracy of off-site tools was 79.4% and the diagnostic accuracy of on-site tools was 84.1%. CONCLUSIONS: The agreement between FFR-CT and invasive FFR is moderate although agreement is highest in vessels with FFR-CT >0.9. Diagnostic accuracy varies widely with FFR-CT value but is above 90% for FFR-CT values >0.90 and <0.49. Furthermore, on-site and off-site tools have similar performance. Ultimately, FFR-CT may be a useful adjunct to CT coronary angiography as a gatekeeper for invasive coronary angiogram.

Coronary microvascular dysfunction and atrial reservoir function.

BACKGROUND: Coronary microvascular dysfunction (CMD) refers to structural and functional abnormalities of the coronary microcirculation, which may be diagnosed using invasive coronary physiology. CMD is responsible for impaired diastolic cardiac function. It has recently been suggested that left atrial strain (LASr) represents a highly sensitive tool for detecting cardiac diastolic function abnormalities. Accordingly, the aim of this study was to investigate the relationship between CMD and LASr. METHODS: Consecutively enrolled patients with non-obstructed coronary arteries (NOCA) underwent CMD and LASr evaluation by invasive thermodilution and noninvasive echocardiography, respectively. RESULTS: Forty-two (42) patients were included, out of which 26 presented with CMD. There were no significant differences between CMD-positive and negative patients in terms of clinical and echocardiographic characteristics. LASr was significantly reduced in patients with CMD (24.6% ± 6.1 vs. 30.3 ± 7.8%, p = 0.01). A moderate correlation was observed between coronary flow reserve and LAsr (r = 0.47, p = 0.002). A multivariate logistic regression analysis demonstrated that CMD was independently associated with LASr (OR = 0.88, 95%CI 0.78-0.99.135, p = 0.04). A LASr cut-off of 25.5% enabled an optimal classification of patients with or without CMD. CONCLUSION: Patients with NOCA and CMD had a significantly reduced LASr compared with patients without CMD, suggesting the early impairment of diastolic function in these patients.

Differential Effect of Aortic Valve Replacement for Severe Aortic Stenosis on Hyperemic and Resting Epicardial Coronary Pressure Indices.

BACKGROUND: Coronary pressure indices to assess coronary artery disease are currently underused in patients with aortic stenosis due to many potential physiological effects that might hinder their interpretation. Studies with varying sample sizes have provided us with conflicting results on the effect of transcatheter aortic valve replacement (TAVR) on these indices. The aim of this meta-analysis was to study immediate and long-term effects of TAVR on fractional flow reserve (FFR) and nonhyperemic pressure ratios (NHPRs). METHODS AND RESULTS: Lesion-specific coronary pressure data were extracted from 6 studies, resulting in 147 lesions for immediate change in FFR analysis and 105 for NHPR analysis. To investigate the long-term changes, 93 lesions for FFR analysis and 68 for NHPR analysis were found. Lesion data were pooled and compared with paired t tests. Immediately after TAVR, FFR decreased significantly (-0.0130±0.0406 SD, P: 0.0002) while NHPR remained stable (0.0003±0.0675, P: 0.9675). Long-term after TAVR, FFR decreased significantly (-0.0230±0.0747, P: 0.0038) while NHPR increased nonsignificantly (0.0166±0.0699, P: 0.0543). When only borderline NHPR lesions were considered, this increase became significant (0.0249±0.0441, P: 0.0015). Sensitivity analysis confirmed our results in borderline lesions. CONCLUSIONS: TAVR resulted in small significant, but opposite, changes in FFR and NHPR. Using the standard cut-offs in patients with severe aortic stenosis, FFR might underestimate the physiological significance of a coronary lesion while NHPRs might overestimate its significance. The described changes only play a clinically relevant role in borderline lesions. Therefore, even in patients with aortic stenosis, an overtly positive or negative physiological assessment can be trusted.

Association of Hypertensive Disorders of Pregnancy With Coronary Microvascular Dysfunction 8 to 10 Years After Delivery.

BACKGROUND: Hypertensive disorders of pregnancy (HDP) are associated with subsequent adverse cardiac remodeling and cardiovascular disease. The role of myocardial microvascular disease among individuals with HDP and left ventricular (LV) remodeling as a potential link to cardiovascular disease is unknown. We aimed to determine whether individuals with HDP history have coronary microvascular dysfunction measured by coronary flow reserve 8 to 10 years after delivery and whether microvascular dysfunction correlates with LV remodeling. METHODS: Individuals with pregnancies delivered from 2008 to 2010 underwent burst-replenishment myocardial contrast echocardiography (2017-2020) to quantify myocardial perfusion at rest and during dobutamine stress. Video intensity versus time data were used to derive ß, the rate of rise of video intensity, a correlate for myocardial blood flow. Coronary flow reserve was calculated as the ratio of ß at peak stress to ß at rest, averaged across LV myocardial regions of interest. RESULTS: We studied 91 individuals (aged 38±6 and 9.1±0.9 years postdelivery) and 19 with a history of HDP. Individuals with coronary microvascular dysfunction (coronary flow reserve <2.0; n=13) had a higher proportion of HDP (46.2% versus 16.7%; P=0.026) and higher prepregnancy body mass index, baseline heart rate, and hemoglobin A1c compared with those without microvascular dysfunction. The association of coronary flow reserve and HDP was attenuated after adjusting for cardiometabolic factors (P=0.133). In exploratory subgroup analyses, individuals with both LV remodeling (relative wall thickness >0.42) and HDP (n=12) had the highest proportion of microvascular dysfunction (41.7% versus +HDP-LV remodeling [n=7] 14.3%; -HDP+LV remodeling [n=26] 7.7%; P=0.0498). CONCLUSIONS: In this small study, HDP history is associated with coronary microvascular dysfunction 1 decade after delivery, findings that may, in part, be driven by metabolic factors including obesity and diabetes. Microvascular dysfunction may contribute to cardiovascular disease among individuals with a history of HDP.

Epicardial fat volume is associated with primary coronary slow-flow phenomenon in patients with severe aortic stenosis undergoing transcatheter valve implantation.

BACKGROUND: Primary coronary slow flow (CSF) is defined as delayed opacification of the distal epicardial vasculature during coronary angiography in the absence of relevant coronary artery stenoses. Microvascular disease is thought to be the underlying cause of this pathology. Epicardial fat tissue (EFT) is an active endocrine organ directly surrounding the coronary arteries that provides pro-inflammatory factors to the adjacent tissue by paracrine and vasocrine mechanisms. The aim of the present study was to investigate a potential association between EFT and primary CSF and whether EFT can predict the presence of primary CSF. METHODS: Between 2016 and 2017, n = 88 patients with high-grade aortic stenosis who were planned for transcatheter aortic valve implantation (TAVI) were included in this retrospective study. EFT volume was measured by pre-TAVI computed tomography (CT) using dedicated software. The presence of primary CSF was defined based on the TIMI frame count from the pre-TAVI coronary angiograms. RESULTS: Thirty-nine of 88 TAVI patients had CSF (44.3%). EFT volume was markedly higher in patients with CSF (142 ml [IQR 107-180] vs. 113 ml [IQR 89-147]; p = 0.009) and was strongly associated with the presence of CSF (OR 1.012 [95%CI 1.002-1.021]; p = 0.014). After adjustment, EFT volume was still an independent predictor of CSF (OR 1.016 [95%CI 1.004-1.026]; p = 0.009). CONCLUSION: Primary CSF was independently associated with increased EFT volume. Further studies are needed to validate this finding and elucidate whether a causal relationship exists.

Interplay Between Systemic Inflammation, Myocardial Injury, and Coronary Microvascular Dysfunction in Rheumatoid Arthritis: Results From the LiiRA Study.

BACKGROUND: Coronary microvascular dysfunction as measured by myocardial flow reserve (MFR) is associated with increased cardiovascular risk in rheumatoid arthritis (RA). The objective of this study was to determine the association between reducing inflammation with MFR and other measures of cardiovascular risk. METHODS AND RESULTS: Patients with RA with active disease about to initiate a tumor necrosis factor inhibitor were enrolled (NCT02714881). All subjects underwent a cardiac perfusion positron emission tomography scan to quantify MFR at baseline before tumor necrosis factor inhibitor initiation, and after tumor necrosis factor inhibitor initiation at 24 weeks. MFR <2.5 in the absence of obstructive coronary artery disease was defined as coronary microvascular dysfunction. Blood samples at baseline and 24 weeks were measured for inflammatory markers (eg, high-sensitivity C-reactive protein [hsCRP], interleukin-1b, and high-sensitivity cardiac troponin T [hs-cTnT]). The primary outcome was mean MFR before and after tumor necrosis factor inhibitor initiation, with Δhs-cTnT as the secondary outcome. Secondary and exploratory analyses included the correlation between ΔhsCRP and other inflammatory markers with MFR and hs-cTnT. We studied 66 subjects, 82% of which were women, mean RA duration 7.4 years. The median atherosclerotic cardiovascular disease risk was 2.5%; 47% had coronary microvascular dysfunction and 23% had detectable hs-cTnT. We observed no change in mean MFR before (2.65) and after treatment (2.64, P=0.6) or hs-cTnT. A correlation was observed between a reduction in hsCRP and interleukin-1b with a reduction in hs-cTnT. CONCLUSIONS: In this RA cohort with low prevalence of cardiovascular risk factors, nearly 50% of subjects had coronary microvascular dysfunction at baseline. A reduction in inflammation was not associated with improved MFR. However, a modest reduction in interleukin-1b and no other inflammatory pathways was correlated with a reduction in subclinical myocardial injury. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02714881.

Evaluation of fractional flow reserve and atherosclerotic plaque characteristics on coronary non-contrast T1-weighted magnetic resonance imaging.

BACKGROUND AND AIMS: The relationship between high-risk coronary plaque characteristics regardless of the severity of lesion stenosis and myocardial ischemia remains unsettled. High-intensity plaques (HIPs) on non-contrast T1-weighted magnetic resonance imaging (T1WI) have been characterized as high-risk coronary plaques. We sought to elucidate whether the presence of coronary HIPs on T1WI influences fractional flow reserve (FFR) in the distal segment of the vessel. METHODS: We retrospectively analyzed 281 vessels in 231 patients with chronic coronary syndrome who underwent invasive FFR measurement and coronary T1WI using a multicenter registry. The plaque-to-myocardial signal intensity ratio (PMR) of the most stenotic lesion was evaluated; a coronary plaque with PMR ≥1.4 was defined as a HIP. RESULTS: The median PMR of coronary plaques on T1WI in vessels with FFR ≤0.80 was significantly higher than that of plaques with FFR >0.80 (1.17 [interquartile range (IQR): 0.99-1.44] vs. 0.97 [IQR: 0.85-1.09]; p < 0.001). Multivariable analysis showed that an increase in PMR of the most stenotic segment was associated with lower FFR (beta-coefficient, -0.050; p < 0.001). The presence of coronary HIPs was an independent predictor of FFR ≤0.80 (odds ratio (OR), 6.18; 95% confidence interval (CI), 1.93-19.77; p = 0.002). Even after adjusting for plaque composition characteristics based on computed tomography angiography, the presence of coronary HIPs was an independent predictor of FFR ≤0.80 (OR, 4.48; 95% CI, 1.19-16.80; p = 0.026). CONCLUSIONS: Coronary plaques with high PMR are associated with low FFR in the corresponding vessel, indicating that plaque morphology might influence myocardial ischemia severity.

Three-Year Clinical Impact of Murray Law-Based Quantitative Flow Ratio and OCT- or FFR-Guidance in Angiographically Intermediate Coronary Lesions.

BACKGROUND: The FORZA trial (FFR or OCT Guidance to Revascularize Intermediate Coronary Stenosis Using Angioplasty) prospectively compared the use of fractional flow reserve (FFR) or optical coherence tomography (OCT) for treatment decisions and percutaneous coronary intervention (PCI) optimization in patients with angiographically intermediate coronary lesions. Murray law-based quantitative-flow-ratio (µQFR) is a novel noninvasive method for the computation of FFR. In the present study, we evaluated the clinical impact of µQFR, FFR, or OCT guidance in FORZA trial lesions at 3-year follow-up. METHODS: µQFR was assessed at baseline and, in the case of a decision to intervene, after (FFR- or OCT-guided) PCI. The baseline µQFR was considered the final µQFR for deferred lesions, and post-PCI µQFR value was taken as final for stented lesions. The primary end point was target vessel failure ([TVF]; cardiac death, target-vessel-related myocardial infarction, and target-vessel-revascularization) at a 3-year follow-up. RESULTS: A total of 419 vessels (199 OCT-guided and 220 FFR-guided) were included in the FORZA trial. µQFR was evaluated in 256 deferred lesions and 159 treated lesions (98 OCT-guided PCI and 61 FFR-guided PCI). In treated lesions, post-PCI µQFR was higher in OCT-group compared with FFR-group (median, 0.93 versus 0.91; P=0.023), and the post-PCI µQFR improvement was greater in FFR-group (0.14 versus 0.08; P<0.0001). At 3-year follow-up, OCT- and FFR-guided treatment decisions resulted in comparable TVF rate (6.7% versus 7.9%; P=0.617). Final µQFR was the only predictor of TVF. µQFR ≤0.89 was associated with 3× increase in TVF (11.6% versus 3.7%; P=0.004). PCI was a predictor of higher final µQFR (odds ratio, 0.22 [95% CI, 0.14-0.34]; P<0.001). CONCLUSIONS: In vessels with angiographically intermediate coronary lesions, OCT-guided PCI resulted in comparable clinical outcomes as FFR-guided PCI. µQFR estimated at the end of diagnostic or interventional procedure predicted 3-year TVF. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01824030.