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OBJECTIVES: Coronary flow reserve (CFR) is a strong predictor of cardiovascular events and prognosis in patients with coronary artery disease. This study aimed to evaluate preoperative factors associated with the unsuccessful restoration of CFR after coronary artery bypass grafting (CABG). METHODS: Included in this study were the 65 patients who presented with functionally significant left anterior descending artery (LAD) lesions confirmed by both fractional flow reserve (FFR) and instantaneous wave-free ratio (iFR), and who underwent successful CABG at our hospital within the study period. After CABG, graft patency was confirmed by coronary computed tomography angiography, and CFR in the LAD artery was measured by echocardiography. We defined postoperative CFR <2.5 as impaired CFR, and CFR ≥2.5 as preserved CFR. RESULTS: Of the 65 patients, 14 patients (22%) showed impaired CFR, while 51 patients had preserved CFR. Patients with impaired CFR had significantly higher HbA1c (6.7% vs. 6.0%, P < 0.01), greater use of insulin (43% vs. 4%, P < 0.01), longer lesion length (33 mm vs. 25 mm, P = 0.044), and lower iFR (0.69 vs 0.81, P = 0.01) than those with preserved CFR, although both groups had comparable FFR (0.65 vs 0.64, P = 0.46). In receiver operating characteristic curve analysis, iFR had a significantly larger area under the curve than FFR in terms of the prediction of impaired CFR (0.74 vs 0.42, P = 0.01). CONCLUSIONS: Poorly-controlled preoperative diabetes, greater reliance on insulin, longer lesion length and lower iFR were associated with postoperative impaired CFR, suggesting the involvement of microvascular dysfunction.
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BACKGROUND: Left ventricular (LV) structural and functional changes have been reported in patients with aortic stenosis (AS) who have undergone transcatheter aortic valve implantation (TAVI); however, the relationship between change in LV structure and systolic function and tissue characteristics assessed via cardiovascular magnetic resonance imaging (CMRI) post-TAVI has been not fully elucidated. This study aimed to investigate this relationship in patients with severe AS who underwent TAVI and CMRI. METHODS: In this retrospective study, 65 patients who underwent TAVI and CMRI at the 6-month follow-up were analyzed. The relationship between percent changes in LV end-diastolic volume (LVEDV), LV end-systolic volume (LVESV), LV ejection fraction (LVEF), and LV mass (LVM) (â¿LVEDV, â¿LVESV, â¿LVEF, and â¿LVM) and those in the native T1 value (â¿native T1) was analyzed using a correlation analysis. Moreover, extracellular volume fraction (ECV) value changes were analyzed. RESULTS: The â¿native T1 significantly decreased from 1292.8 (1269.9-1318.4) ms at pre-TAVI to 1282.3 (1262.6-1310.2) ms at the 6-month follow-up (P = 0.022). A significant positive correlation between â¿LVEDV, â¿LVESV, and â¿LVM and â¿native T1 (r = 0.351, P = 0.004; r = 0.339, P = 0.006; r = 0.261, P = 0.035, respectively) and a tendency toward a negative correlation between â¿LVEF and â¿native T1 (r = -0.237, P = 0.058) were observed. The ECV value increased significantly from 26.7 % (25.3-28.3) to 28.2 % (25.7-30.5) (P = 0.002). CONCLUSIONS: The decrease in native T1 might be associated with LV reverse remodeling. Evaluating structural and functional changes using CMRI may be useful for patient management.
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In Japan, stocked chum salmon (Oncorhynchus keta) fry may have become the perfect prey for non-native brown trout (Salmo trutta), which are popular targets of anglers. If this is the case, fry stocking which is intended to boost commercial fishing may be helping to sustain the populations of an invasive predator. We used dietary and biochemical analyses to examine whether brown trout quickly restore their nutritional status following wintertime declines by preying upon chum salmon fry that are stocked in spring. We targeted six rivers in Hokkaido, Japan, three with fry stocking and three without. Changes in brown trout condition factor, triglyceride contents in muscle and serum, serum insulin-like growth factor-1 (IGF-1; an indicator of short-term growth), and docosahexaenoic acid (DHA; an essential fatty acid abundant in fish) content in muscle were examined between before stocking and during the stocking period in the six rivers. Dietary analysis showed that brown trout preyed on fry during the stocking period in all stocked rivers. Their nutritional status tended to be higher during the stocking period than before stocking in stocked rivers, but not in unstocked rivers. These results suggest that the massive stocking of chum salmon fry provides brown trout with the perfect prey to quickly restore their nutritional status and fuel increased growth; this may therefore be a controversial issue among stakeholders.
Subject(s)
Oncorhynchus keta , Trout , Animals , Japan , Insulin-Like Growth Factor I/metabolism , Insulin-Like Growth Factor I/analysis , Fisheries , Triglycerides/blood , Triglycerides/metabolism , Docosahexaenoic Acids/metabolism , Docosahexaenoic Acids/analysis , Rivers , Predatory Behavior , SeasonsABSTRACT
PURPOSE: Saphenous vein grafts (SVGs) sometimes occur as vein graft stenosis or failure in coronary artery bypass grafting. The purpose of this study was to detect the factors affecting vein graft atherosclerosis. METHODS: We performed two analysis. In the first analysis, we enrolled 120 grafts using conventionally harvested saphenous vein graft (C-SVG) and followed-up with multiple coronary computed tomography angiography (CCTA). We examined the factors that contribute to the graft atherosclerosis defined by graft failure at subsequent CCTA or substantial progression of graft stenosis (a decrease of ≥0.6 mm in diameter). In the second analysis, 66 grafts using no-touch harvested saphenous vein graft (N-SVG) were compared with those in the first analysis using C-SVG, focusing on the differences in intraoperative factors using propensity score-matched analysis. RESULTS: In the first analysis, graft atherosclerosis+ group comprised 27 grafts, which had a larger SVG diameter, lower graft velocity, and higher graft/native ratio in diameter than the graft atherosclerosis- group. In the multivariable analysis, slow graft velocity and graft/native ≥2 in diameter were independently associated with the graft atherosclerosis. In the second analysis, the N-SVG group had a much greater graft velocity than the C-SVG group. CONCLUSION: Lower graft velocity and higher graft/native ratio in diameter were associated with the graft atherosclerosis. The N-SVG group had increased graft velocity, which may contribute to prevent the graft atherosclerosis.(Trial registration: UMIN Clinical Trial Registry no. UMIN000050482. Registered 3 March 2023, retrospectively registered.).
Subject(s)
Atherosclerosis , Saphenous Vein , Humans , Atherosclerosis/diagnostic imaging , Constriction, Pathologic , Coronary Angiography , Coronary Artery Bypass/adverse effects , Coronary Artery Bypass/methods , Follow-Up Studies , Saphenous Vein/diagnostic imaging , Saphenous Vein/transplantation , Treatment Outcome , Vascular PatencyABSTRACT
Debranching thoracic endovascular aortic repair may disturb the implantation of a cardiac implantable electronic device in the anterior thoracic region. In case 1, the bypass graft between the right axillary artery, left axillary artery, and left common carotid artery disturbed pacemaker implantation from the left anterior thoracic region. Therefore, right-sided implantation was selected. By contrast, in case 2, the bypass graft between axillary arteries in the anterior thoracic region was visible on fluoroscopy, and we performed conventional left-sided pacemaker implantation with extra-thoracic puncture. The pacemaker implantations were successful in both cases. The implantation strategies were affected by the number of debranched arteries and visibility of the bypass graft.
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Digital coherent transmission features a very large transmission bandwidth and has played a main role in core optical transmission networks. With the progress of semiconductor technologies, practical coherent transceivers with rates over 100 Gbaud are becoming feasible. With such advances, the transceiver components must have lower power consumption and lower costs, and it becomes important to know how each component contributes to the overall transmission performance. Here, to decompose the effects of noise factors in high-baud-rate DP-16QAM transmissions, we used the theoretical relationship between the bit error rate (BER) and noise-to-signal ratio (NSR) and performed linear analyses. The NSR could be decomposed into individual noise contributions according to dependences on the inverse signal and local photocurrents. The obtained parameters were shown to be useful for predicting required optical signal-to-noise ratio (ROSNR) characteristics.
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Purpose: Optimal strategy for transcatheter aortic valve implantation (TAVI) in patients with coronary artery disease (CAD) is unresolved. We evaluated the surgical outcomes of hybrid coronary artery bypass grafting (CABG) and TAVI in elderly patients. Methods: We retrospectively evaluated patients who underwent simultaneous TAVI and CABG at Wakayama Medical University, Japan. All patients underwent off-pump CABG (OPCAB) including minimally invasive cardiac surgery (MICS-CABG). In an earlier period, OPCAB + transfemoral TAVI (TF-TAVI) was the only method used, while in a later period, we introduced MICS-CABG and alternative approaches for TAVI. Results: Twenty-seven patients were enrolled, the average age was 83.6 ± 5.1 years. In the MICS-CABG and TAVI group, average patient age was higher (87.0 ± 3.1 years) than in the earlier group. Thirty-day and in-hospital mortalities were zero. Incomplete revascularization rate was 33.3% and one patient required percutaneous coronary intervention after the operation. Graft patency rate was 100%. In MICS-CABG group, the number of distal anastomoses was smaller (1.29, range 1-2), but the number of days required to re-starting walking and postoperative hospital stay were shorter, and the rate of discharge to home was higher (100%) than in the other groups. Conclusions: Although 33.3% of patients did not achieve complete revascularization, there was no 30-day or in-hospital mortality. TAVI and hybrid OPCAB, including MICS-CABG, were suggested to be feasible treatment in elderly patients.
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Increases in prey population size can affect the physiology and ecology of upper-trophic level organisms. This phenomenon is known as a bottom-up effect. For example, the increased abundance of prey resources can trigger physiological (internal) changes in predators, such as improvements in nutritional status. However, these physiological aspects of bottom-up effects have not been considered. In this study, we tested the hypothesis that white-spotted charr Salvelinus leucomaenis, a salmonid fish, increases body stores of omega-3 fatty acids, especially docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), by preying upon stocked hatchery-reared masu salmon Oncorhynchus masou fry in streams. The dynamics of fatty acid contents in charr inhabiting salmon-stocked and unstocked streams clearly support this hypothesis: fatty acid contents (DHA, EPA, and total fatty acid) increased after stocking in stocked streams, but not in unstocked streams. In addition, DHA increased with increasing body size of white-spotted charr and vice versa for EPA. The impacts of human activities, such as fish stocking, on freshwater ecosystems are a matter of serious concern for conservation. Future attempts to gain a comprehensive understanding of the impacts of fish stocking should consider not only community ecology but also physiology.
Subject(s)
Oncorhynchus , Salmonidae , Animals , Humans , Salmon , Docosahexaenoic Acids , Eicosapentaenoic Acid , Ecosystem , Fatty AcidsABSTRACT
A 62-year-old male was admitted to our hospital with worsening dyspnea. Chest X-ray revealed dextrocardia, and echocardiography revealed decreased right ventricular function, a severely dilated tricuspid annulus, a massive tricuspid, and trivial mitral regurgitation. Patch augmentation of the tricuspid leaflet with auto-pericardium and ring annuloplasty with a flat-type upside-down artificial ring to fit the dextrocardia heart was performed. Echocardiography 4 years after the operation showed trivial regurgitation. Supplementary Information: The online version contains supplementary material available at 10.1007/s12055-023-01477-9.
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BACKGROUND: Postoperative delirium in intensive care is common and associated with mortality, cognitive impairment, prolonged hospital stays and high costs. We evaluate whether a nurse-led orientation program could reduce the incidence of delirium in the intensive care unit after cardiovascular surgery. METHODS: In this retrospective cohort study, we enrolled patients admitted to the intensive care unit for planned cardiovascular surgery between January 2020 and December 2021. A nurse-led orientation program based on a preoperative visit was routinely introduced from January 2021. We assessed the association between these visits and postoperative delirium in the intensive care unit. We also assessed predictors of postoperative delirium with baseline and intraoperative characteristics. RESULTS: Among 253 patients with planned cardiovascular surgery, 128 (50.6%) received preoperative visits. Valve surgery comprised 44.7%, coronary surgery 31.6%, and aortic surgery 20.9%. Cardiopulmonary bypass use and transcatheter surgery were 60.5% and 12.3%, respectively. Incidence of delirium was lower in patients that received preoperative visits, and median hospital stay was shorter than in those without visits (18 patients [14.1%] vs 34 patients [27.2%], P < 0.01; 14 days vs 17 days, P < 0.01). After adjusting predefined confounders, preoperative visits were independently associated with decreased incidence of delirium (adjusted odds ratio [aOR] 0.45; 95% confidence interval [95% CI] 0.22-0.84). Other predictors of delirium were higher European System for Cardiac Operative Risk Evaluation II score and lower minimum intraoperative cerebral oxygen saturation. CONCLUSIONS: A preoperative nurse-led orientation program was associated with reduction of postoperative delirium and could be effective against postoperative delirium after cardiovascular surgery. Trial registration UMIN Clinical Trial Registry no. UMIN000048142. Registered 22, July, 2022, retrospectively registered, https://center6.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000054862 .
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BACKGROUND: The site of arterial cannulation is an important consideration in the prevention of cerebral infarction after total arch replacement. We compared the outcomes of cannulation of the bilateral axillary artery, the femoral artery, and central cannulation in total arch replacement. METHODS: Enrolled were 242 patients, categorized into three groups according to the arterial cannulation site used: bilateral axillary artery group, 124 patients; femoral artery group, 88 patients; central cannulation group, 30 patients. Selective cerebral perfusion was used for brain protection in all patients. Surgical outcomes, including the incidence of postoperative cerebral infarction, were compared between the groups. RESULTS: Cardiopulmonary bypass time and lower-body circulatory arrest time were significantly shorter in the bilateral axillary artery group. Frozen elephant trunk procedure was performed in 54% of the bilateral axillary artery group (P < .001), and concomitant coronary artery bypass graft surgery was performed in 40% of the central cannulation group (P < .01). Hospital mortality in the bilateral axillary artery group was 1.6%, compared with 1.1% in the femoral artery group, and 0% in the central cannulation group (P = .72). The incidence of permanent neurologic deficit was significantly lower in the bilateral axillary artery group (0.8%) than in the central cannulation group (13%; P = .02). Logistic regression analysis indicated that bilateral axillary artery perfusion was a significant factor in the prevention of permanent neurologic deficit (odds ratio 0.10, P = .03). CONCLUSIONS: Recent technical advances using bilateral axillary artery perfusion and frozen elephant trunk technique were associated with shortening cardiopulmonary bypass time and prevention of postoperative cerebral infarction in total arch replacement.
Subject(s)
Aorta, Thoracic , Axillary Artery , Humans , Male , Female , Aorta, Thoracic/surgery , Middle Aged , Aged , Retrospective Studies , Postoperative Complications/prevention & control , Postoperative Complications/epidemiology , Perfusion/methods , Blood Vessel Prosthesis Implantation/methods , Blood Vessel Prosthesis Implantation/adverse effects , Femoral Artery , Cerebral Infarction/prevention & control , Cerebral Infarction/etiology , Cerebral Infarction/epidemiology , Treatment Outcome , Cardiopulmonary Bypass/methodsABSTRACT
Tumours or tumour-like lesions around the aortic valve are relatively rare and are difficult to diagnose. We report an interesting case of calcified thrombi in the Valsalva sinuses and coronary cusps that mimicked an aortic valve tumour. A 68-year-old man presented with a 20-mm calcified mass in the non-coronary and left-coronary cusps extending to their corresponding Valsalva sinuses, which was detected by echocardiography and contrast-enhanced computed tomography. The lesions were resected to establish the diagnosis and prevent systemic embolization. Intraoperative and histopathological examination revealed an atrophied non-coronary leaflet and calcified atherosclerotic lesions of the Valsalva sinuses and contiguous parts of the cusps, with ulceration and fibrin thrombi. The lesions were resected and aortic valve replacement was performed to avoid aortic valve dysfunction. The patient's atrial fibrillation was controlled, and anticoagulants were discontinued 3 months postoperatively. Surgery to establish the diagnosis and to prevent systemic thromboembolism was thought to be reasonable, even in the absence of valvular dysfunction.
Subject(s)
Neoplasms , Sinus of Valsalva , Thrombosis , Aged , Anticoagulants , Aortic Valve/diagnostic imaging , Aortic Valve/surgery , Fibrin , Humans , Male , Sinus of Valsalva/diagnostic imaging , Sinus of Valsalva/surgery , Thrombosis/diagnostic imaging , Thrombosis/pathology , Thrombosis/surgeryABSTRACT
Background: Impaired coronary flow reserve (CFR) portends a poor prognosis in patients with aortic stenosis. The present study aims to investigate how CFR changes over one year after transcatheter aortic valve implantation (TAVI) in patients with severe aortic stenosis, and to explore factors related to the changes. Methods: Consecutive patients undergoing TAVI were registered. CFR in the left anterior descending artery was measured by transthoracic echocardiography on three occasions pre-TAVI, one-day post-TAVI, and one-year post-TAVI. Results: A total of 59 patients were enrolled, 46 of whom completed one-year follow-up. CFR was impaired in 35 (59.3%) patients pre-TAVI, but the impairment was only seen in 2 patients (4%) one-year post-TAVI. CFR value improved from 1.75 (1.50-2.10) cm/s pre-TAVI, to 2.00 (1.70-2.30) one-day post-TAVI, and further to 2.60 (2.30-3.10) one-year post-TAVI (P < 0.001). The median difference in CFR between pre-TAVI and one-year post-TAVI was 0.90 (0.53-1.20). Patients with significant improvement of CFR (more than the median value of 0.9) had larger aortic valve area (1.55 [1.38-1.92] vs. 1.36 cm2 [1.26-1.69], P = 0.042) and greater improvement in left ventricular ejection fraction (3.10 [-1.67-4.24] vs. -1.46 [-3.42-1.48] percentage points, P = 0.019) than those without. Conclusions: CFR is impaired in a considerable proportion of patients with severe aortic stenosis, but improvement is seen immediately after TAVI, and one year later. Patients with significant improvement of CFR had larger aortic valve area and greater increase in left ventricular ejection fraction after TAVI.
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OBJECTIVES: The selection of arterial cannulation site is an important decision to avoid cerebral complication for total arch replacement(TAR). We report the surgical outcome of TAR using bilateral axillary artery perfusion in our hospital. METHODS: Between January 2012 and June 2020, 97 patients who underwent elective TAR for atherosclerotic aneurysms were enrolled in this study. Among them, bilateral axillary artery perfusion was used for 81 patients, and frozen elephant trunk( FET) procedure were used for 34 patients. In the case of FET procedure, translocated TAR was performed with distal anastomosis between the left common carotid artery and the left subclavian artery. The left subclavian artery was reconstructed by rerouting the graft used for the left axillary artery perfusion. RESULTS: There were no perioperative cerebral infarction and no hospital deaths. The mean operation time was 420 minutes. Compared to the conventional elephant trunk method, the FET method significantly reduced the operation time to 381 minutes. CONCLUSIONS: Bilateral axillary artery perfusion could contribute to reduce the cerebral infarction in TAR and facilitate the FET procedure.
Subject(s)
Aortic Aneurysm, Thoracic , Aortic Dissection , Blood Vessel Prosthesis Implantation , Aortic Dissection/surgery , Aorta, Thoracic/surgery , Aortic Aneurysm, Thoracic/surgery , Axillary Artery/surgery , Humans , Perfusion , Treatment OutcomeABSTRACT
The feeding ecology of scarinine parrotfishes on tropical coral reefs has received considerable attention in the past few decades; nonetheless, relatively few studies have been conducted in high-latitude reefs. Among the Indo-Pacific Scarus species, Scarus ovifrons is unique, being largely restricted to the warm temperate waters of Japan. Nonetheless, there is very little information available on the feeding ecology of this species. In this study, the authors used acoustic telemetry to detect the diel vertical movement patterns of S. ovifrons, video survey to detect its feeding depths and substrata and focal follow survey and genetic analysis to identify algae composition on the feeding scars at Kashiwajima Island, southwestern Japan (32° 46' N, 132° 38' E). Acoustic telemetry revealed that S. ovifrons spent most of its time in shallow water (<10 m) during the day and slept in deeper water (10-15 m) at night. Video and focal follow surveys revealed that most fishes of various sizes regularly took bites on epilithic algae and detrital materials on rocky substrata at depths of <10 m, but large fishes (>40 cm total length) sometimes took bites directly on live corals (Acropora solitaryensis) at the 5 m depth zone where live tabular corals dominated the benthos. Molecular phylogenetic analyses revealed that epilithic algae collected from feeding scars were mainly composed of Rhodophyta, and coralline algae were less often targeted. Overall, this study revealed that S. ovifrons feeds mostly at depths <10 m, and the feeding algae substrata of the species are similar to those of tropical coral reef parrotfishes.
Subject(s)
Anthozoa , Coral Reefs , Animals , Feeding Behavior , Fishes , Japan , PhylogenyABSTRACT
Adventitial cystic disease of the femoral vein is an extremely rare condition; therefore, diagnosis, treatments, surgical approaches and long-term prognosis are not well defined. We report the case of a 67-year-old man with femoral vein adventitial cystic disease complicated with deep vein thrombosis. He presented with right leg oedema. Ultrasound, computed tomography and magnetic resonance imaging revealed a mass in the femoral vein, and deep vein thrombosis was not detected at the time. However, venous return disorder worsened due to the mass causing a deep vein thrombosis in the femoral vein, and anticoagulation therapy with edoxaban was administered. Subsequently, deep vein thrombosis in the femoral vein disappeared, but remained in the lower calf. The mass and femoral vein were completely resected and reconstructed with an expanded polytetrafluoroethylene graft. No recurrence was observed over 3 years and 3 months.
Subject(s)
Cysts , Vascular Diseases , Venous Thrombosis , Adventitia , Aged , Cysts/complications , Cysts/diagnostic imaging , Cysts/surgery , Femoral Vein/diagnostic imaging , Femoral Vein/surgery , Humans , Male , Venous Thrombosis/diagnostic imaging , Venous Thrombosis/etiology , Venous Thrombosis/surgeryABSTRACT
AIM: During surgery for an aortic arch aneurysm, aortic plaque in the descending aorta should be evaluated, but there are currently no suitable biomarkers for it. Surgeons should be especially aware of cerebral embolism from femoral perfusion and of peripheral embolism from stent graft deployment. Cystatin C is a known useful marker of renal dysfunction with a role as a biomarker for severity of coronary artery disease. In the absence of a suitable biomarker for aortic plaque in the descending aorta, we examine cystatin C as a candidate. METHODS: In all, 75 patients who underwent surgery for an aortic arch aneurysm were enrolled. They were divided into two groups, depending on whether they had chronic kidney disease or not. The serum cystatin C value and creatinine value were evaluated preoperatively. The aortic plaque volume ratio and components in the descending aorta were calculated from preoperative enhanced computed tomography. RESULTS: The soft plaque volume ratio was higher in patients with chronic kidney disease than in patients without it. Cystatin C positively correlated with the total aortic plaque volume ratio in all cases, and it positively correlated with the soft plaque volume ratio in both groups. Creatinine had no correlation with any type of plaque volume ratio in either group. In patients without chronic kidney disease, the soft plaque volume ratio was higher in patients with higher cystatin C levels than in patients with normal levels. CONCLUSION: The preoperative serum cystatin C level could be a biomarker of aortic plaque in the descending aorta in patients with an aortic arch aneurysm.
Subject(s)
Aortic Aneurysm, Thoracic/blood , Aortic Aneurysm, Thoracic/complications , Cystatin C/blood , Plaque, Atherosclerotic/blood , Plaque, Atherosclerotic/diagnosis , Aged , Aged, 80 and over , Aortic Aneurysm, Thoracic/surgery , Biomarkers/blood , Creatinine/blood , Female , Humans , Male , Plaque, Atherosclerotic/complications , Renal Insufficiency, Chronic/blood , Renal Insufficiency, Chronic/complications , Retrospective StudiesABSTRACT
BACKGROUND: We aimed to assess an impact of instantaneous wave-free ratio (iFR) on a graft failure after coronary artery bypass grafting (CABG). METHODS AND RESULTS: A total of 131 coronary arteries from 88 patients who underwent invasive coronary angiography, intracoronary pressure measurements, CABG, and scheduled follow-up coronary computed tomography angiography within one year were investigated. All studied arteries had FFR <0.80. The rate of graft failure was significantly higher in vessels with negative iFR (>0.89) than in those with positive iFR (<0.89) (25.7% vs. 7.3%, p = 0.012). The graft failure rates increased as the preoperative iFR values rose (iFR <0.80, 3.3%; iFR: 0.80-0.84, 5.6%; iFR: 0.85-0.89, 16.0%; iFR: 0.90-0.94, 28.0%; and iFR: 0.95-1.00, 50.0%; p = 0.002). A cut-off value of iFR to predict graft failures was determined as 0.84 by receiver-operating characteristic curve analysis with sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of 88%, 62%, 25%, 97%, and 66%, respectively. CONCLUSIONS: The risk of graft failure becomes higher, as the preoperative iFR increases. The graft failure is significantly more frequent when a bypass graft is anastomosed on vessels with negative iFR than those with positive iFR.