Physiological Assessment with iFR prior to FFR Measurement in Left Main Disease.

Despite guideline-based recommendation of the interchangeable use of instantaneous wave-free ratio (iFR) and fractional flow reserve (FFR) to guide revascularization decision-making, iFR/FFR could demonstrate different physiological or clinical outcomes in some specific patient or lesion subsets. Therefore, we sought to investigate the impact of difference between iFR and FFR-guided revascularization decision-making on clinical outcomes in patients with left main disease (LMD). In this international multicenter registry of LMD with physiological interrogation, we identified 275 patients in whom physiological assessment was performed with both iFR/FFR. Major adverse cardiovascular event (MACE) was defined as a composite of death, non-fatal myocardial infarction, and ischemia-driven target lesion revascularization. The receiver-operating characteristic analysis was performed for both iFR/FFR to predict MACE in respective patients in whom revascularization was deferred and performed. In 153 patients of revascularization deferral, MACE occurred in 17.0% patients. The optimal cut-off values of iFR and FFR to predict MACE were 0.88 (specificity:0.74; sensitivity:0.65) and 0.76 (specificity:0.81; sensitivity:0.46), respectively. The area under the curve (AUC) was significantly higher for iFR than FFR (0.74; 95%CI 0.62-0.85 vs. 0.62; 95%CI 0.48-0.75; p = 0.012). In 122 patients of coronary revascularization, MACE occurred in 13.1% patients. The optimal cut-off values of iFR and FFR were 0.92 (specificity:0.93; sensitivity:0.25) and 0.81 (specificity:0.047; sensitivity:1.00), respectively. The AUCs were not significantly different between iFR and FFR (0.57; 95%CI 0.40-0.73 vs. 0.46; 95%CI 0.31-0.61; p = 0.43). While neither baseline iFR nor FFR was predictive of MACE in patients in whom revascularization was performed, iFR-guided deferral seemed to be safer than FFR-guided deferral.

Spontaneous Remission Without Steroid Therapy in Isolated Cardiac Sarcoidosis with Severe Left Ventricular Systolic Dysfunction.

Spontaneous remission is often observed in extracardiac cases of sarcoidosis, such as skin sarcoidosis. However, for cardiac sarcoidosis (CS), the prognosis is unfavorable. Although corticosteroids are the first-line treatment for CS, data regarding the natural history of isolated CS are limited. We describe a rare case of isolated CS with severe left ventricular systolic dysfunction that improved without steroid therapy.

Sex Differences in 5-Year Outcomes After Deferral of Revascularization Following Physiological Coronary Assessment.

Background: The relationship between sex differences and long-term outcomes after fractional flow reserve (FFR)- and instantaneous wave-free ratio (iFR)-guided deferral of revascularization has yet to be elucidated. Methods and Results: From the J-CONFIRM registry (long-term outcomes of Japanese patients with deferral of coronary intervention based on FFR in a multicenter registry), this study included 432 lesions from 385 patients (men, 323 lesions in 286 patients; women, 109 lesions in 99 patients) with paired data of FFR and iFR. The primary endpoint was the cumulative 5-year incidence of target vessel failure (TVF), including cardiac death, target vessel-related myocardial infarction, and clinically driven target vessel revascularization. The median FFR value was lower in men than in women (0.85 [0.81, 0.88] vs. 0.87 [0.83, 0.91], P=0.002), but the iFR value was comparable between men and women (0.94 [0.90, 0.98] vs. 0.93 [0.89, 0.98], P=0.26). The frequency of discordance between FFR and iFR was comparable between men and women (19.5% vs. 23.9%, P=0.34), although with different discordance patterns (P=0.036). The cumulative incidence of 5-year TVF did not differ between men and women after adjustment for baseline characteristics (13.9% vs. 6.9%, adjusted hazard ratio 1.82 [95% confidence interval: 0.44-7.56]; P=0.41). Conclusions: Despite sex differences in the results for physiological indexes, the 5-year TVF in deferred lesions did not differ between men and women after adjustment for baseline characteristics.

Safety and potential usefulness of sequential intracoronary acetylcholine and ergonovine administration for spasm provocation testing.

BACKGROUND: Although guidelines recommend intracoronary acetylcholine (ACh) and ergonovine (ER) provocation testing for diagnosis of vasospastic angina, the feasibility and safety of sequential (combined) use of both pharmacological agents during the same catheterization session remain unclear. OBJECTIVES: In this study, we investigated the feasibility and safety of sequential intracoronary ACh and ER administration for coronary spasm provocation testing. METHODS: The study included 235 patients who showed positive results on ACh and ER provocation testing. Initial intracoronary ACh administration was followed by ER administration for left coronary artery (LCA) spasm provocation testing. Subsequently, the right coronary artery (RCA) was subjected to sequential ACh and ER administration for provocation testing. The primary outcome of the study was the safety of sequential intracoronary ACh and ER provocation testing, which was assessed based on a composite of all-cause death, sustained ventricular tachycardia and fibrillation, and cardiogenic shock. RESULTS: Even in patients with negative results on sequential intracoronary ACh and ER provocation testing in the LCA and only ACh administration into the RCA, additional administration of ER into the RCA showed a positive provocation test result in 33 of 235 (14.0%) patients; three (1.3%) patients developed adverse effects (cardiogenic shock occurred in all cases) during LCA provocation testing. We observed no deaths attributable to spasm provocation testing. CONCLUSION: Sequential administration of intracoronary ACh and ER was associated with a relatively low major complication rate and may be safe and potentially useful for diagnosis of vasospastic angina.

Safety and potential usefulness of novel coronary spasm provocation testing protocolCoronary spasm represents a subtype of ischemic heart disease, potentially leading to heart attack. Although guidelines recommend intracoronary administration of different pharmacological agents, acetylcholine (ACh) and ergonovine (ER), for coronary spasm provocation testing, the feasibility and safety of sequential (combined) use of both drugs are unclear. In the present study, we showed that sequential administration of intracoronary ACh and ER was associated with a relatively low major complication rate and may be safe and potentially useful for diagnosis of coronary vasospasm.

One-year outcomes of patients undergoing percutaneous coronary intervention with the revived directional coronary atherectomy catheter: Insights from the J-PCI OUTCOME registry.

OBJECTIVES: We sought to investigate the 1-year outcomes, including all-cause and cardiovascular mortality, major adverse cardiovascular events (MACEs), and major bleeding, of patients undergoing percutaneous coronary intervention (PCI) with or without the revived directional coronary atherectomy (DCA) catheter in a Japanese nationwide registry. BACKGROUND: Clinical data regarding the midterm outcomes of patients undergoing PCI with DCA are scarce in contemporary real-world practice. METHODS: We analyzed the data of 74,764 patients who underwent PCI at 179 hospitals from January 2017 to December 2018. The baseline characteristics and 1-year outcomes of patients with stable coronary artery disease or unstable angina who underwent PCI with or without DCA were assessed. RESULTS: Overall, 431 patients (0.6%) underwent PCI with DCA. Patients in the DCA group were younger and predominantly male, with fewer comorbidities than patients in the non-DCA group. Stentless PCI with DCA following additional drug-coated balloon (DCB) angioplasty was the dominant strategy in the DCA group (43.6%). One-year outcomes, including all-cause mortality (1.2% in the DCA group vs. 2.5% in the non-DCA group, respectively, p = 0.075), cardiovascular death (0.9% vs. 1.0%, p = 0.69), MACEs (1.9% vs. 1.8%, p = 0.96), and nonfatal major bleeding requiring readmission (1.2% vs. 1.4%, p = 0.62), were comparable between the two groups. In the DCA group, 1-year outcomes were comparable, regardless of whether the stent or DCB was used. CONCLUSIONS: One-year clinical outcomes after PCI with DCA in patients with stable coronary artery disease or unstable angina are acceptable, regardless of stent use.

Prognostic Impact of Renal Function on 5-Year Outcomes After Fractional Flow Reserve-Guided Deferral of Revascularization.

Background Chronic kidney disease (CKD) might influence fractional flow reserve (FFR) value, potentially attenuating its prognostic utility. However, few large-scale data are available regarding clinical outcomes after FFR-guided deferral of revascularization in patients with CKD. Methods and Results From the J-CONFIRM registry (Long-Term Outcomes of Japanese Patients With Deferral of Coronary Intervention Based on Fractional Flow Reserve in Multicenter Registry), 1218 patients were divided into 3 groups according to renal function: (1) non-CKD (estimated glomerular filtration rate ≥60 mL/min per 1.73 m2), n=385; (2) CKD (estimated glomerular filtration rate 15-59 mL/min per 1.73 m2, n=763); and (3) end-stage renal disease (ESRD) (eGFR <15 mL/min per 1.73 m2, n=70). The primary study end point was the cumulative 5-year incidence of target vessel failure (TVF), defined as a composite of cardiac death, target vessel myocardial infarction, and clinical driven target vessel revascularization. Cumulative 5-year incidence of TVF was significantly higher in the ESRD group than in the CKD and non-CKD group, whereas it did not differ between the CKD and non-CKD groups (26.3% versus 11.9% versus 9.5%, P<0.001). Although the 5-year TVF risk increased as the FFR value decreased regardless of renal function, patients with ESRD had a remarkably higher risk of TVF at every FFR value than those with CKD and non-CKD. Conclusions At 5 years, patients with ESRD showed a higher incidence of TVF than patients with CKD and non-CKD, although with similar outcomes between patients with CKD and non-CKD. Patients with ESRD had an excess risk of 5-year TVF at every FFR value compared with those with CKD and non-CKD. Registration URL: https://www.umin.ac.jp; Unique identifier: UMIN000014473.

Impact of stenosis resistance and coronary flow capacity on fractional flow reserve and instantaneous wave-free ratio discordance: a combined analysis of DEFINE-FLOW and IDEAL.

BACKGROUND: The pressure-derived parameters fractional flow reserve (FFR) and the emerging instantaneous wave-free ratio (iFR) are the most widely applied invasive coronary physiology indices to guide revascularisation. However, approximately 15-20% of intermediate stenoses show discordant FFR and iFR, and therapeutical consensus is lacking. AIMS: We sought to associate hyperaemic stenosis resistance index, coronary flow reserve (CFR) and coronary flow capacity (CFC) to FFR/iFR discordance. METHODS: We assessed pressure and flow measurements of 647 intermediate lesions (593 patients) of two multi-centre international studies. RESULTS: FFR and iFR were discordant in 15% of all lesions (97 out of 647). FFR+/iFR- lesions had similar hyperaemic average peak velocity (hAPV), CFR and CFC as FFR-/iFR- lesions, whereas FFR-/iFR+ lesions had similar hAPV, CFR and CFC as FFR+/iFR+ lesions (p > 0.05 for all). FFR+/iFR- lesions were associated with lower baseline stenosis resistance, but not hyperaemic stenosis resistance, compared with FFR-/iFR+ lesions (p < 0.001). CONCLUSIONS: Discordance with FFR+/iFR- is characterised by maximal flow values, CFR, and CFC patterns similar to FFR-/iFR- concordance that justifies conservative therapy. Discordance with FFR-/iFR+ on the other hand, is characterised by low flow values, CFR, and CFC patterns similar to iFR+/FFR+ concordance that may benefit from percutaneous coronary intervention.

Deferred Versus Performed Revascularization for Left Main Coronary Disease With Hemodynamic Significance.

BACKGROUND: The majority of randomized controlled trials of revascularization decision-making excludes left main coronary artery disease (LMD). Therefore, contemporary clinical outcomes of patients with stable coronary artery disease and LMD with proven ischemia remain poorly understood. The aim of this study was to assess the long-term clinical outcomes of physiologically significant LMD according to the treatment strategies of revascularization versus revascularization deferral. METHODS: In this international multicenter registry of stable LMD interrogated with the instantaneous wave-free ratio, patients with physiologically significant ischemia (instantaneous wave-free ratio ≤0.89) were analyzed according to the coronary revascularization (n=151) versus revascularization deferral (n=74). Propensity score matching was performed to adjust for baseline clinical characteristics. The primary end point was a composite of death, nonfatal myocardial infarction, and ischemia-driven target lesion revascularization of left main stem. The secondary end points were as follows: cardiac death or spontaneous LMD-related myocardial infarction; and ischemia-driven target lesion revascularization of left main stem. RESULTS: At a median follow-up period of 2.8 years, the primary end point occurred in 11 patients (14.9%) in the revascularized group and 21 patients (28.4%) in the deferred group (hazard ratio, 0.42 [95% CI, 0.20-0.89]; P=0.023). For the secondary end points, cardiac death or LMD-related myocardial infarction occurred significantly less frequently in the revascularized group (0.0% versus 8.1%; P=0.004). The rate of ischemia-driven target lesion revascularization of left main stem was also significantly lower in the revascularized group (5.4% versus 17.6%; hazard ratio, 0.20 [95% CI, 0.056-0.70]; P=0.012). CONCLUSIONS: In patients who underwent revascularization for stable coronary artery disease and physiologically significant LMD determined by instantaneous wave-free ratio, the long-term clinical outcomes were significantly improved as compared with those in whom revascularization was deferred.

Physiology-guided PCI versus CABG for left main coronary artery disease: insights from the DEFINE-LM registry.

There have been no studies comparing clinical outcomes of physiology-guided revascularization in patients with unprotected left main coronary disease (ULMD) between percutaneous coronary intervention (PCI) vs. coronary artery bypass grafting (CABG). The aim of this study was to assess the long-term clinical outcomes between PCI and CABG of patients with physiologically significant ULMD. From an international multicenter registry of ULMD patients interrogated with instantaneous wave-free ratio (iFR), we analyzed data from 151 patients (85 PCI vs. 66 CABG) who underwent revascularization according to the cutoff value of iFR ≤ 0.89. Propensity score matching was employed to adjust for baseline clinical characteristics. The primary endpoint was a composite of all-cause death, non-fatal myocardial infarction, and ischemia-driven target lesion revascularization. The secondary endpoints were the individual components of the primary endpoint. Mean age was 66.6 (± 9.2) years, 79.2% male. Mean SYNTAX score was 22.6 (± 8.4) and median iFR was 0.83 (IQR 0.74-0.87). After performing propensity score matching analysis, 48 patients treated with CABG were matched to those who underwent PCI. At a median follow-up period of 2.8 years, the primary endpoint occurred in 8.3% in PCI group and 20.8% in CABG group, respectively (HR 3.80; 95% CI 1.04-13.9; p = 0.043). There was no difference in each component of the primary event (p > 0.05 for all). Within the present study, iFR-guided PCI was associated with lower cardiovascular events rate in patients with ULMD and intermediate SYNTAX score, as compared to CABG. State-of-the-art PCI vs. CABG for ULMD. Study design and primary endpoint in patients with physiologically significant ULMD. MACE was defined as the composite of all-cause death, non-fatal myocardial infarction, and target lesion revascularization. The blue line denotes the PCI arm, and the red line denotes the CABG arm. PCI was associated with significantly lower risk of MACE than CABG. CABG: coronary artery bypass grafting; iFR: instantaneous wave-free ratio; MACE: major adverse cardiovascular events; PCI: percutaneous coronary intervention; ULMD: unprotected left main coronary artery disease.

Long-Term Outcomes in Elderly Patients After Deferral of Coronary Revascularization Guided by Fractional Flow Reserve.

BACKGROUND: Little evidence is available regarding the long-term outcome in elderly patients after deferral of revascularization based on fractional flow reserve (FFR).Methods and Results: From the J-CONFIRM registry (long-term outcomes of Japanese patients with deferral of coronary intervention based on fractional flow reserve in multicenter registry), 1,262 patients were divided into 2 groups according to age: elderly and younger patients (aged ≥75 or <75 years, respectively). The primary endpoint was the cumulative 5-year incidence of target vessel failure (TVF), defined as a composite of cardiac death, target vessel-related myocardial infarction (TVMI), and clinically driven target vessel revascularization (CDTVR). Cumulative 5-year incidence of TVF was not significantly different between elderly and younger patients (14.3% vs. 10.8%, P=0.12). Cardiac death occurred more frequently in elderly patients than younger patients (4.4% vs. 0.8%, P<0.001), whereas TVMI and CDTVR did not differ between groups (1.3% vs. 0.9%, P=0.80; 10.7% vs. 10.1%, P=0.80, respectively). FFR values in lesions with diameter stenosis <50% were significantly higher in elderly patients than in younger patients (0.88±0.07 vs. 0.85±0.07, P=0.01), whereas this relationship was not observed in those with diameter stenosis ≥50%. CONCLUSIONS: Elderly patients had no excess risk of ischemic events related to the deferred coronary lesions by FFR, although FFR values in mild coronary artery stenosis were modestly different between elderly and younger patients.

Thrombotic Risk and Cardiovascular Events in Patients With Revascularization Deferral After Fractional Flow Reserve Assessment.

OBJECTIVES: The aim of this study was to evaluate the impact of thrombotic risk on the occurrence of cardiovascular events in patients with coronary artery disease with deferred revascularization after fractional flow reserve (FFR) measurements. BACKGROUND: Deferral of revascularization on the basis of FFR is generally considered to be safe, but after deferral, some patients have cardiovascular events over time. METHODS: From J-CONFIRM registry (Long-Term Outcomes of Japanese Patients With Deferral of Coronary Intervention Based on Fractional Flow Reserve in Multicenter Registry), 1,263 patients with deferral of revascularization on the basis of FFR were evaluated. The association between thrombotic risk as assessed by CREDO-Kyoto (Coronary Revascularization Demonstrating Outcome Study in Kyoto) thrombotic score and 5-year target vessel failure (TVF) and major adverse cardiac and cerebrovascular events (MACCE) was investigated. RESULTS: FFR and high thrombotic risk (HTR) were associated with increased risk for 5-year TVF (FFR per 0.01-unit decrease: HR: 1.08; 95% CI: 1.05-1.11; P < 0.001; HTR: HR: 2.16; 95% CI: 1.37-3.39; P < 0.001) and MACCE (FFR per 0.01-unit decrease: HR: 1.05; 95% CI: 1.02-1.06; P < 0.001; HTR: HR: 2.11; 95% CI: 1.56-2.84; P = 0.001). Patients with HTR had higher risk for 5-year TVF (HR: 2.30; 95% CI: 1.45-3.66; P < 0.001) and MACCE (HR: 2.34; 95% CI: 1.75-3.13; P < 0.001) than those without HTR, even when they had negative FFR. CONCLUSIONS: Assessment of thrombotic risk provides additional prognostic value to FFR in predicting 5-year TVF and MACCE in patients with deferral of revascularization after FFR measurements. (Long-Term Outcomes of Japanese Patients With Deferral of Coronary Intervention Based on Fractional Flow Reserve in Multicenter Registry; UMIN000014473).

Association of guideline-directed medical therapy adherence with outcomes after fractional flow reserve-based deferral of revascularization.

AIMS: Guideline-directed medical therapy (GDMT) is essential to prevent future cardiovascular events in chronic coronary syndrome (CCS) patients. However, whether achieving optimal GDMT could improve clinical outcomes in CCS patients with deferred lesions based on fraction flow reserve (FFR) remains thoroughly investigated. We sought to evaluate the association of GDMT adherence with long-term outcomes after FFR-based deferral of revascularization in a real-world registry. METHODS AND RESULTS: This is a post-hoc analysis of the J-CONFIRM registry (long-term outcomes of Japanese patients with deferral of coronary intervention based on fractional flow reserve in multicentre registry). Optimal GDMT was defined as combining four types of medications: antiplatelet drug, angiotensin-converting enzyme inhibitor/angiotensin II receptor blocker, beta-blocker, and statin. After stratifying patients by the number of individual GDMT agents at 2 years, landmark analysis was conducted to assess the relationship between GDMT adherence at 2 years and 5-year major adverse cardiac events (MACEs), defined as a composite of all-cause death, target vessel-related myocardial infarction, clinically driven target vessel revascularization. Compared with the suboptimal GDMT group (continuing ≤3 types of medications, n = 974), the optimal GDMT group (n = 139) showed a lower 5-year incidence of MACE (5.2% vs. 12.4%, P = 0.02). The optimal GDMT was associated with a lower risk of MACE (hazard ratio: 0.41; 95% confidence interval: 0.18 to 0.92; P = 0.03). CONCLUSION: Patients with optimal GDMT were associated with better outcomes, suggesting the importance of achieving optimal GDMT on long-term prognosis in CCS patients after FFR-guided deferral of revascularization.

Five-Year Outcomes After Fractional Flow Reserve-Based Deferral of Revascularization in Chronic Coronary Syndrome: Final Results From the J-CONFIRM Registry.

BACKGROUND: Little large-scale data is available about the long-term (beyond 3 years) clinical outcomes after fractional flow reserve (FFR)-based deferral of revascularization in clinical practice. We sought to assess the 5-year outcomes after deferral of revascularization based on FFR. METHODS: The J-CONFIRM registry (Long-Term Outcomes of Japanese Patients With Deferral of Coronary Intervention Based on Fractional Flow Reserve in Multicenter Registry) prospectively enrolled 1263 patients with 1447 lesions in whom revascularization was deferred based on FFR from 28 Japanese centers. The primary study end point was the cumulative 5-year incidence of target vessel failure (TVF), including cardiac death, target vessel-related myocardial infarction, and clinically driven target vessel revascularization. RESULTS: Five-year follow-up was completed in 92.2% of patients. The 5-year TVF rate was 11.6% in deferred lesions, mainly driven by clinically driven target vessel revascularization (9.8%). Cardiac death and target vessel-related myocardial infarction were 1.9% and 0.95%, respectively. Cumulative 5-year incidence of TVF was similar between the FFR 0.75 to 0.80 and 0.81 to 0.85 groups even after adjustment for baseline characteristics (12.2% versus 13.0%, inverse probability-weighted hazard ratio, 0.86 [95% CI, 0.46-1.60]; P=0.63). Compared with the almost normal FFR (0.86-1.00) group, the significant (<0.75) and borderline (0.75-0.85) FFR groups showed a higher incidence of TVF at 5 years (29.9% versus 12.8% versus 8.6%, P<0.001). Independent predictors of the 5-year TVF were hemodialysis, FFR value, left main coronary artery lesion, prior percutaneous coronary intervention, and male sex. CONCLUSIONS: The 5-year TVF rate was 11.6% in deferred lesions, mainly driven by clinically driven target vessel revascularization. Notably, cardiac death and target vessel-related myocardial infarction rarely occurred during the follow-up. Our findings highlight the long-term safety of FFR-based deferral of revascularization in patients with chronic coronary syndrome. Registration: URL: https://www.umin.ac.jp/ctr; Unique identifier: UMIN000014473.

Coexistence of Spontaneous Coronary Artery Dissection, Takotsubo Cardiomyopathy, and Myocardial Bridge.

We report a case of spontaneous coronary artery dissection located next to a myocardial bridge in a patient with concomitant takotsubo cardiomyopathy. A fusion image with multidetector-row computed tomography and single-photon emission computed tomography played an important role in the diagnosis of these lesions. (Level of Difficulty: Advanced.).

Correlation of Intravascular Ultrasound and Instantaneous Wave-Free Ratio in Patients With Intermediate Left Main Coronary Artery Disease.

BACKGROUND: There is great degree of interobserver variability in the visual angiographic assessment of left main coronary disease (LMCD). Fractional flow reserve and intravascular ultrasound are often used in this setting. The use of instantaneous wave-free ratio (iFR) for evaluation of LMCD has not been well studied. The aim of this study is to evaluate the use of iFR in the assessment of angiographically intermediate LMCD. METHODS: This is an international multicenter retrospective observational study of patients who underwent both iFR and intravascular ultrasound evaluation for angiographically intermediate LMCD. An independent core laboratory performed blinded off-line analysis of all intravascular ultrasound data. A minimum lumen area of 6 mm2 was used as the cutoff for significant disease. RESULTS: One hundred twenty-five patients (mean age, 68.4±9.5 years, 84.8% male) were included in this analysis. Receiver operating curve analysis showed that an iFR of ≤0.89 identified minimum lumen area <6 mm2 with an area under the curve of 0.77 (77% sensitivity, 66% specificity; P<0.0001). Among the 69 patients without ostial left anterior descending artery or left circumflex artery disease, receiver operating curve analysis showed that an iFR of ≤0.89 identified minimum lumen area <6 mm2 with an area under the curve of 0.84 (70% sensitivity, 84% specificity; P<0.0001). The correlation was not significantly different when the body surface area was considered. CONCLUSIONS: In this study, in patients with intermediate LMCD, iFR of ≤0.89 correlates with intravascular ultrasound minimum lumen area <6 mm2 regardless of body surface area. The current study supports the use of iFR for the evaluation of intermediate LMCD.

Inter-observer differences in interpretation of coronary pressure-wire pullback data by non-expert interventional cardiologists.

The physiological pattern of coronary artery disease as determined by pressure-wire (PW)-pullback is important for decision-making of revascularization and risk stratification of patients. However, it remains unclear whether inter-observer differences in interpreting PW-pullback data are subject to the expertise of physicians. This study sought to investigate the subjectivity of this assessment among non-experts. Expert interventional cardiologists classified 545 PW-pullback traces into physiologically focal or physiologically diffuse disease pattern. Defining expert-consensus as the reference standard, we evaluated ten non-expert doctors' classification performance. Observers were stratified equally by two ways: (i) years of experience as interventional cardiologists (middle-level vs. junior-level) and (ii) volume of institutions where they belonged to (high-volume center vs. low-volume center). When judged against the expert-consensus, the agreement of non-expert observers in assessing physiological pattern of disease (focal or diffuse) ranged from 69.1 to 85.0% (p for heterogeneity < 0.0001). There was no evidence for a moderating effect of years of experience; the pooled accuracy of middle-level doctors was 78.8% (95% confidential interval [CI] 72.8-84.7%) vs. 79.1% for junior-level doctors (95% CI 75.9-82.2%, p = 0.95 for difference). On the other hand, we observed a significant moderating effect of center volume. Accuracy across non-experts in high-volume centers was 82.7% (95% CI 80.3-85.1%) vs. 75.1% for low-volume centers (95% CI 71.9-78.3%, p = 0.0002 for difference). Interpretation of PW-pullback by non-expert interventional cardiologists was considerably subjective.

Safety of Revascularization Deferral of Left Main Stenosis Based on Instantaneous Wave-Free Ratio Evaluation.

OBJECTIVES: The aim of this study was to assess the long-term clinical outcomes of patients with left main coronary artery (LM) stenosis in whom treatment strategy was based on the instantaneous wave-free ratio (iFR). BACKGROUND: The overall safety of iFR to guide revascularization decision making in patients with stable coronary artery disease has been established. However, no study has examined the safety of deferral of revascularization of LM disease on the basis of iFR. METHODS: This multicenter observational study included 314 patients in whom LM stenosis was deferred (n = 163 [51.9%]) or revascularized (n = 151 [48.1%]) according to the iFR cutoff ≤0.89. The primary endpoint was a composite of all-cause death, nonfatal myocardial infarction, and ischemia-driven target lesion revascularization. The secondary endpoints were each individual component of the primary endpoint and also cardiac death. RESULTS: At a median follow-up period of 30 months, the primary endpoint occurred in 15 patients (9.2%) in the deferred group and 22 patients (14.6%) in the revascularized group (hazard ratio: 1.45; 95% confidence interval: 0.75 to 2.81; p = 0.26), indicating no evidence of a significant difference between the 2 groups. For the secondary endpoints, findings in the iFR-based deferral and revascularization groups were as follows: all-cause death, 3.7% versus 4.6%; cardiac death, 1.2% versus 2.0%; nonfatal myocardial infarction, 2.5% versus 5.3%; and target lesion revascularization, 4.3% versus 5.3% (p > 0.05 for all). CONCLUSIONS: Deferral of revascularization of LM stenosis on the basis of iFR appears to be safe, with similar long-term outcomes to those in patients in whom LM revascularization was performed according to iFR values.

Per-Vessel Level Analysis of Fractional Flow Reserve and Instantaneous Wave-Free Ratio Discordance　- Insights From the AJIP Registry.

BACKGROUND: The per-vessel level impact of physiological pattern of disease on the discordance between fractional flow reserve (FFR) and instantaneous wave-free ratio (iFR) has not been clarified.Methods and Results:Using the AJIP registry, vessels with FFR/iFR discordance (133/671 [19.8%]) were analyzed. In the left anterior descending artery (LAD), physiologically diffuse disease, as assessed by pressure-wire pullback, was associated with FFR-/iFR+ (83.3% [40/48]), while physiologically focal disease was associated with FFR+/iFR- (57.4% [31/54]), significantly (P<0.0001). These differences were not significant in non-LAD (P=0.17). CONCLUSIONS: The impact of physiological pattern of disease on FFR/iFR discordance is more pronounced in the LAD.

Two-Year Outcomes of Asymptomatic vs. Symptomatic Patients After Deferral of Revascularization Based on Fractional Flow Reserve　- Insights From the J-CONFIRM Registry.

Background: The effect of symptoms on clinical outcomes after deferral of revascularization based on fractional flow reserve (FFR) remains poorly understood. Methods and Results: From the J-CONFIRM (Long-Term Outcomes of Japanese Patients With Deferral of Coronary Intervention Based on Fractional Flow Reserve in Multicenter) Registry, this study evaluated 1,215 patients with stable coronary artery disease, including symptomatic and asymptomatic patients (n=571 and 644, respectively). The primary endpoint was the cumulative 2-year incidence of target vessel failure (TVF), including cardiac death, target vessel-related myocardial infarction (TVMI), and clinically driven target vessel revascularization (CDTVR). An inverse probability weighted analysis was performed to adjust for the differences in baseline clinical characteristics between the 2 groups. At 2 years, the TVF rate did not differ significantly between symptomatic and asymptomatic patients (6.5% vs. 4.9%, respectively; P=0.15) or between symptomatic and asymptomatic patients with lesions with an FFR ≤0.80 (8.0% vs. 12.3%, respectively; P=0.20). Conversely, symptomatic patients showed significantly higher rates of TVF (6.2% vs. 3.3%; P=0.01) and CDTVR (6.2% vs. 3.1%; P=0.009) than asymptomatic patients, regardless of negative FFR values (>0.80). Conclusions: Despite negative FFR values, symptomatic patients were at higher risk of TVF than asymptomatic patients, driven primarily by a higher rate of CDTVR. Conversely, those with a positive FFR were likely to develop TVF regardless of their symptoms.

Two-Year Outcomes After Deferral of Revascularization Based on Fractional Flow Reserve: The J-CONFIRM Registry.

BACKGROUND: The safety of fractional flow reserve (FFR)-based deferral of revascularization remains to be fully established in real-world practice. We sought to assess clinical outcomes after deferral of revascularization based on FFR. METHODS: The J-CONFIRM registry (Long-Term Outcomes of Japanese Patients With Deferral of Coronary Intervention Based on Fractional Flow Reserve in Multicenter Registry) prospectively enrolled 1263 patients with 1447 lesions in whom revascularization was deferred based on FFR at 28 Japanese centers. The primary study end point was the cumulative 2-year incidence of target vessel failure, including cardiac death, target-vessel related myocardial infarction, and clinically driven target vessel revascularization. RESULTS: The mean FFR was 0.86±0.06. At 2 years, the target vessel failure rate was 5.5% in deferred lesions, mainly driven by a high rate of clinically driven target vessel revascularization (5.2%), and significantly increased with decreasing FFR, especially in the proximal location. Cardiac death and target-vessel related myocardial infarction rarely occurred during the 2-year follow-up (0.41% and 0.41%, respectively). Independent predictors of 2-year target vessel failure were FFR value (per 0.01 decrease; hazard ratio [HR] 1.07 [95% CI, 1.04-1.11], P<0.001), left main coronary artery lesion (HR, 5.89 [95% CI, 2.72-12.8], P<0.001), moderately to severely calcified lesion (HR, 2.49 [95% CI, 1.36-4.58]; P=0.003), hemodialysis (HR, 2.90 [95% CI, 1.11-7.58]; P=0.03), and right coronary artery lesion (HR, 1.78 [95% CI, 1.02-3.11], P=0.042). CONCLUSIONS: The J-CONFIRM registry demonstrated the 2-year target vessel failure rate was 5.5% in deferred lesions, highlighting the safety of FFR-based deferral of revascularization in daily practice. CLINICAL TRIAL REGISTRATION: URL: http://www.umin.ac.jp. Unique identifier: UMIN000014473.