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Arnold AD, Howard JP, Chiew K, Kerrigan WJ, de Vere F, Johns HT, Churlilov L, Ahmad Y, Keene D, Shun-Shin MJ, Cole GD, Kanagaratnam P, Sohaib SMA, Varnava A, Francis DP, Whinnett ZI. Right ventricular pacing for hypertrophic obstructive cardiomyopathy: meta-analysis and meta-regression of clinical trials. EUROPEAN HEART JOURNAL. QUALITY OF CARE & CLINICAL OUTCOMES 2020; 5:321-333. [PMID: 30715300 PMCID: PMC6775860 DOI: 10.1093/ehjqcco/qcz006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 01/25/2019] [Accepted: 01/31/2019] [Indexed: 01/25/2023]
Abstract
Aims Right ventricular pacing for left ventricular outflow tract gradient reduction in hypertrophic obstructive cardiomyopathy remains controversial. We undertook a meta-analysis for echocardiographic and functional outcomes. Methods and results Thirty-four studies comprising 1135 patients met eligibility criteria. In the four blinded randomized controlled trials (RCTs), pacing reduced gradient by 35% [95% confidence interval (CI) 23.2–46.9, P < 0.0001], but there was only a trend towards improved New York Heart Association (NYHA) class [odds ratio (OR) 1.82, CI 0.96–3.44; P = 0.066]. The unblinded observational studies reported a 54.3% (CI 44.1–64.6, P < 0.0001) reduction in gradient, which was a 18.6% greater reduction than the RCTs (P = 0.0351 for difference between study designs). Observational studies reported an effect on unblinded NYHA class at an OR of 8.39 (CI 4.39–16.04, P < 0.0001), 450% larger than the OR in RCTs (P = 0.0042 for difference between study designs). Across all studies, the gradient progressively decreased at longer follow durations, by 5.2% per month (CI 2.5–7.9, P = 0.0001). Conclusion Right ventricular pacing reduces gradient in blinded RCTs. There is a non-significant trend to reduction in NYHA class. The bias in assessment of NYHA class in observational studies appears to be more than twice as large as any genuine treatment effect.
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Warisawa T, Cook CM, Rajkumar C, Howard JP, Seligman H, Ahmad Y, El Hajj S, Doi S, Nakajima A, Nakayama M, Goto S, Vera-Urquiza R, Sato T, Kikuta Y, Kawase Y, Nishina H, Petraco R, Al-Lamee R, Nijjer S, Sen S, Nakamura S, Lerman A, Matsuo H, Francis DP, Akashi YJ, Escaned J, Davies JE. Safety of Revascularization Deferral of Left Main Stenosis Based on Instantaneous Wave-Free Ratio Evaluation. JACC Cardiovasc Interv 2020; 13:1655-1664. [DOI: 10.1016/j.jcin.2020.02.035] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Accepted: 02/25/2020] [Indexed: 01/28/2023]
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Arnold AD, Howard JP, Gopi A, Chan CP, Ali N, Keene D, Shun-Shin MJ, Ahmad Y, Wright IJ, Ng FS, Linton NW, Kanagaratnam P, Peters NS, Rueckert D, Francis DP, Whinnett ZI. Discriminating electrocardiographic responses to His-bundle pacing using machine learning. CARDIOVASCULAR DIGITAL HEALTH JOURNAL 2020; 1:11-20. [PMID: 32954375 PMCID: PMC7484933 DOI: 10.1016/j.cvdhj.2020.07.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND His-bundle pacing (HBP) has emerged as an alternative to conventional ventricular pacing because of its ability to deliver physiological ventricular activation. Pacing at the His bundle produces different electrocardiographic (ECG) responses: selective His-bundle pacing (S-HBP), non-selective His bundle pacing (NS-HBP), and myocardium-only capture (MOC). These 3 capture types must be distinguished from each other, which can be challenging and time-consuming even for experts. OBJECTIVE The purpose of this study was to use artificial intelligence (AI) in the form of supervised machine learning using a convolutional neural network (CNN) to automate HBP ECG interpretation. METHODS We identified patients who had undergone HBP and extracted raw 12-lead ECG data during S-HBP, NS-HBP, and MOC. A CNN was trained, using 3-fold cross-validation, on 75% of the segmented QRS complexes labeled with their capture type. The remaining 25% was kept aside as a testing dataset. RESULTS The CNN was trained with 1297 QRS complexes from 59 patients. Cohen kappa for the neural network's performance on the 17-patient testing set was 0.59 (95% confidence interval 0.30 to 0.88; P <.0001), with an overall accuracy of 75%. The CNN's accuracy in the 17-patient testing set was 67% for S-HBP, 71% for NS-HBP, and 84% for MOC. CONCLUSION We demonstrated proof of concept that a neural network can be trained to automate discrimination between HBP ECG responses. When a larger dataset is trained to higher accuracy, automated AI ECG analysis could facilitate HBP implantation and follow-up and prevent complications resulting from incorrect HBP ECG analysis.
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Ahmad Y, Howard JP, Arnold A, Prasad M, Seligman H, Cook CM, Warisawa T, Shun‐Shun M, Ali Z, Parikh MA, Al‐Lamee R, Sen S, Francis D, Moses JW, Leon MB, Stone GW, Karmpaliotis D. Complete Revascularization by Percutaneous Coronary Intervention for Patients With ST-Segment-Elevation Myocardial Infarction and Multivessel Coronary Artery Disease: An Updated Meta-Analysis of Randomized Trials. J Am Heart Assoc 2020; 9:e015263. [PMID: 32476540 PMCID: PMC7429036 DOI: 10.1161/jaha.119.015263] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Accepted: 05/04/2020] [Indexed: 01/10/2023]
Abstract
Background For patients with ST-segment-elevation myocardial infarction (STEMI) and multivessel coronary artery disease, the optimal treatment of the non-infarct-related artery has been controversial. This up-to-date meta-analysis focusing on individual clinical end points was performed to further evaluate the benefit of complete revascularization with percutaneous coronary intervention for patients with STEMI and multivessel coronary artery disease. Methods and Results We systematically identified all randomized trials comparing complete revascularization with percutaneous coronary intervention to culprit-only revascularization for multivessel disease in STEMI and performed a random-effects meta-analysis. The primary efficacy end point was cardiovascular death analyzed on an intention-to-treat basis. Secondary end points included all-cause mortality, myocardial infarction, and unplanned revascularization. Ten studies (7542 patients) were included: 3664 patients were randomized to complete revascularization and 3878 to culprit-only revascularization. Across all patients, complete revascularization was superior to culprit-only revascularization for reduction in the risk of cardiovascular death (relative risk [RR], 0.68; 95% CI, 0.47-0.98; P=0.037; I2=21.8%) and reduction in the risk of myocardial infarction (RR, 0.65; 95% CI, 0.54-0.79; P<0.0001; I2=0.0%). Complete revascularization also significantly reduced the risk of unplanned revascularization (RR, 0.37; 95% CI, 0.28-0.51; P<0.0001; I2=64.7%). The difference in all-cause mortality with percutaneous coronary intervention was not statistically significant (RR, 0.85; 95% CI, 0.69-1.04; P=0.108; I2=0.0%). Conclusions For patients with STEMI and multivessel disease, complete revascularization with percutaneous coronary intervention significantly improves hard clinical outcomes including cardiovascular death and myocardial infarction. These data have implications for clinical practice guidelines regarding recommendations for complete revascularization following STEMI.
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Ahmad Y, Howard JP, Francis DP. Response by Ahmad et al to Letter Regarding Article "Effects of Percutaneous Coronary Intervention on Death and Myocardial Infarction Stratified by Stable and Unstable Coronary Artery Disease: A Meta-Analysis of Randomized Controlled Trials". Circ Cardiovasc Qual Outcomes 2020; 13:e006862. [PMID: 32482084 DOI: 10.1161/circoutcomes.120.006862] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Warisawa T, Cook CM, Seligman H, Howard JP, Ahmad Y, Rajkumar C, Doi S, Nakayama M, Tanigaki T, Omori H, Nakajima A, Yamanaka F, Goto S, Yakuta Y, Karube K, Uetani T, Kikuta Y, Shiono Y, Kawase Y, Nishina H, Nakamura S, Escaned J, Akashi YJ, Matsuo H, Davies JE. Per-Vessel Level Analysis of Fractional Flow Reserve and Instantaneous Wave-Free Ratio Discordance - Insights From the AJIP Registry. Circ J 2020; 84:1034-1038. [PMID: 32321880 DOI: 10.1253/circj.cj-19-0785] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
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.
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Warisawa T, Howard JP, Cook CM, Ahmad Y, Doi S, Nakayama M, Goto S, Yakuta Y, Karube K, Seike F, Uetani T, Murai T, Kikuta Y, Shiono Y, Kawase Y, Shun-Shin MJ, Kaihara T, Higuma T, Ishibashi Y, Matsuda H, Nishina H, Matsuo H, Escaned J, Akashi YJ, Davies JE. Inter-observer differences in interpretation of coronary pressure-wire pullback data by non-expert interventional cardiologists. Cardiovasc Interv Ther 2020; 36:289-297. [PMID: 32430763 DOI: 10.1007/s12928-020-00673-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Accepted: 05/12/2020] [Indexed: 10/24/2022]
Abstract
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.
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Warisawa T, Cook CM, Howard JP, Ahmad Y, Doi S, Nakayama M, Goto S, Yakuta Y, Karube K, Shun-Shin MJ, Petraco R, Sen S, Nijjer S, Al Lamee R, Ishibashi Y, Matsuda H, Escaned J, di Mario C, Francis DP, Akashi YJ, Davies JE. Physiological Pattern of Disease Assessed by Pressure-Wire Pullback Has an Influence on Fractional Flow Reserve/Instantaneous Wave-Free Ratio Discordance. Circ Cardiovasc Interv 2020; 12:e007494. [PMID: 31084237 PMCID: PMC6553990 DOI: 10.1161/circinterventions.118.007494] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
BACKGROUND Fractional flow reserve (FFR) and instantaneous wave-free ratio (iFR) disagree on the hemodynamic significance of a coronary lesion in ≈20% of cases. It is unknown whether the physiological pattern of disease is an influencing factor for this. This study assessed whether the physiological pattern of coronary artery disease influences discordance between FFR and iFR measurement. METHODS AND RESULTS Three-hundred and sixty intermediate coronary lesions (345 patients; mean age, 64.4±10.3 years; 76% men) with combined FFR, iFR, and iFR pressure-wire pullback were included for analysis from an international multicenter registry. Cut points for hemodynamic significance were FFR ≤0.80 and iFR ≤0.89, respectively. Lesions were classified into FFR+/iFR+ (n=154; 42.7%), FFR-/iFR+ (n=38; 10.6%), FFR+/iFR- (n=41; 11.4%), and FFR-/iFR- (n=127; 35.3%) groups. The physiological pattern of disease was classified according to the iFR pullback recordings as predominantly physiologically focal (n=171; 47.5%) or predominantly physiologically diffuse (n=189; 52.5%). Median FFR and iFR were 0.80 (interquartile range, 0.75-0.85) and 0.89 (interquartile range, 0.86-0.92), respectively. FFR disagreed with iFR in 22% (79 of 360). The physiological pattern of disease was the only influencing factor relating to FFR/iFR discordance: predominantly physiologically focal was significantly associated with FFR+/iFR- (58.5% [24 of 41]), and predominantly physiologically diffuse was significantly associated with FFR-/iFR+ (81.6% [31 of 38]; P<0.001 for pattern of disease between FFR+/iFR- and FFR-/iFR+ groups). CONCLUSIONS The physiological pattern of coronary artery disease was an important influencing factor for FFR/iFR discordance.
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Ahmad Y, Howard JP, Francis DP. Response by Ahmad et al to Letter Regarding Article, "Effects of Percutaneous Coronary Intervention on Death and Myocardial Infarction Stratified by Stable and Unstable Coronary Artery Disease: A Meta-Analysis of Randomized Controlled Trials". Circ Cardiovasc Qual Outcomes 2020; 13:e006642. [PMID: 32283970 DOI: 10.1161/circoutcomes.120.006642] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Cook CM, Howard JP, Ahmad Y, Shun-Shin MJ, Sethi A, Clesham GJ, Tang KH, Nijjer SS, Kelly PA, Davies JR, Malik IS, Kaprielian R, Mikhail G, Petraco R, Warisawa T, Al-Janabi F, Karamasis GV, Mohdnazri S, Gamma R, de Waard GA, Al-Lamee R, Keeble TR, Mayet J, Sen S, Francis DP, Davies JE. How Do Fractional Flow Reserve, Whole-Cycle PdPa, and Instantaneous Wave-Free Ratio Correlate With Exercise Coronary Flow Velocity During Exercise-Induced Angina? Circ Cardiovasc Interv 2020; 13:e008460. [PMID: 32200646 DOI: 10.1161/circinterventions.119.008460] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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Howard JP, Tan J, Shun-Shin MJ, Mahdi D, Nowbar AN, Arnold AD, Ahmad Y, McCartney P, Zolgharni M, Linton NWF, Sutaria N, Rana B, Mayet J, Rueckert D, Cole GD, Francis DP. Improving ultrasound video classification: an evaluation of novel deep learning methods in echocardiography. ACTA ACUST UNITED AC 2020; 3. [PMID: 32226937 DOI: 10.21037/jmai.2019.10.03] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Echocardiography is the commonest medical ultrasound examination, but automated interpretation is challenging and hinges on correct recognition of the 'view' (imaging plane and orientation). Current state-of-the-art methods for identifying the view computationally involve 2-dimensional convolutional neural networks (CNNs), but these merely classify individual frames of a video in isolation, and ignore information describing the movement of structures throughout the cardiac cycle. Here we explore the efficacy of novel CNN architectures, including time-distributed networks and two-stream networks, which are inspired by advances in human action recognition. We demonstrate that these new architectures more than halve the error rate of traditional CNNs from 8.1% to 3.9%. These advances in accuracy may be due to these networks' ability to track the movement of specific structures such as heart valves throughout the cardiac cycle. Finally, we show the accuracies of these new state-of-the-art networks are approaching expert agreement (3.6% discordance), with a similar pattern of discordance between views.
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Lerman A, Toya T, Hajj SE, Warisawa T, Nan J, Cook C, Rajkumar C, Howard J, Seligman H, Ahmad Y, Doi S, Nakajima A, Nakayama M, Goto S, Vera-Urquiza R, Sato T, Kikuta Y, Kawase Y, Nishina H, Nakamura S, Matsuo H, Escaned J, Akashi Y, Davies JE. COMPARISON OF INTRAVASCULAR ULTRASOUND-DERIVED MINIMUM LUMEN AREA AND INSTANTANEOUS WAVE-FREE RATIO IN LEFT MAIN CORONARY ARTERY DISEASE. J Am Coll Cardiol 2020. [DOI: 10.1016/s0735-1097(20)32019-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Vendrik J, Ahmad Y, Eftekhari A, Howard JP, Wijntjens GWM, Stegehuis VE, Cook C, Terkelsen CJ, Christiansen EH, Koch KT, Piek JJ, Sen S, Baan J. Long-Term Effects of Transcatheter Aortic Valve Implantation on Coronary Hemodynamics in Patients With Concomitant Coronary Artery Disease and Severe Aortic Stenosis. J Am Heart Assoc 2020; 9:e015133. [PMID: 32102615 PMCID: PMC7335578 DOI: 10.1161/jaha.119.015133] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Background As younger patients are being considered for transcatheter aortic valve implantation (TAVI), the assessment and treatment of concomitant coronary artery disease is taking on increased importance. Methods and Results Thirteen contemporary lower-risk patients with TAVI with severe aortic stenosis (AS) and moderate-severe coronary lesions were included. Patients underwent assessment of coronary hemodynamics in the presence of severe AS (pre-TAVI), in the absence of severe AS (immediately post-TAVI), and at longer-term follow-up (6 months post-TAVI). Fractional flow reserve decreased from 0.85 (0.76-0.88) pre-TAVI to 0.79 (0.74-0.83) post-TAVI, and then to 0.71 (0.65-0.77) at 6-month follow-up (P<0.001 for all comparisons). Conversely, instantaneous wave-free ratio was not significantly different: 0.82 (0.80-0.90) pre-TAVI, 0.83 (0.77-0.88) post-TAVI, and 0.83 (0.73-0.89) at 6 months (P=0.735). These changes are explained by the underlying coronary flow. Hyperemic whole-cycle coronary flow (fractional flow reserve flow) increased from 26.36 cm/s (23.82-31.82 cm/s) pre-TAVI to 30.78 cm/s (29.70-34.68 cm/s) post-TAVI (P=0.012), to 40.20 cm/s (32.14-50.00 cm/s) at 6-month follow-up (P<0.001 for both comparisons). Resting flow during the wave-free period of diastole was not significantly different: 25.48 cm/s (21.12-33.65 cm/s) pre-TAVI, 24.54 cm/s (20.74-27.88 cm/s) post-TAVI, and 25.89 cm/s (22.57-28.96 cm/s) at 6 months (P=0.500). Conclusions TAVI acutely improves whole-cycle hyperemic coronary flow, with ongoing sustained improvements at longer-term follow-up. This enhanced response to hyperemic stimuli appears to make fractional flow reserve assessment less suitable for patients with severe AS. Conversely, resting diastolic flow is not significantly influenced by the presence of severe AS. Resting indices of coronary stenosis severity, therefore, appear to be more appropriate for this patient population, although large-scale prospective randomized trials will be required to determine the role of coronary physiology in patients with severe AS.
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Chacko L, P Howard J, Rajkumar C, Nowbar AN, Kane C, Mahdi D, Foley M, Shun-Shin M, Cole G, Sen S, Al-Lamee R, Francis DP, Ahmad Y. Effects of Percutaneous Coronary Intervention on Death and Myocardial Infarction Stratified by Stable and Unstable Coronary Artery Disease: A Meta-Analysis of Randomized Controlled Trials. Circ Cardiovasc Qual Outcomes 2020; 13:e006363. [PMID: 32063040 PMCID: PMC7034389 DOI: 10.1161/circoutcomes.119.006363] [Citation(s) in RCA: 95] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Supplemental Digital Content is available in the text. In patients presenting with ST-segment–elevation myocardial infarction, percutaneous coronary intervention (PCI) reduces mortality when compared with fibrinolysis. In other forms of coronary artery disease (CAD), however, it has been controversial whether PCI reduces mortality. In this meta-analysis, we examine the benefits of PCI in (1) patients post–myocardial infarction (MI) who did not receive immediate revascularization; (2) patients who have undergone primary PCI for ST-segment–elevation myocardial infarction but have residual coronary lesions; (3) patients who have suffered a non–ST-segment–elevation acute coronary syndrome; and (4) patients with truly stable CAD with no recent infarct. This analysis includes data from the recently presented International Study of Comparative Health Effectiveness with Medical and Invasive Approaches (ISCHEMIA) and Complete versus Culprit-Only Revascularization Strategies to Treat Multivessel Disease after Early PCI for STEMI (COMPLETE) trials.
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Al-Lamee RK, Shun-Shin MJ, Howard JP, Nowbar AN, Rajkumar C, Thompson D, Sen S, Nijjer S, Petraco R, Davies J, Keeble T, Tang K, Malik I, Bual N, Cook C, Ahmad Y, Seligman H, Sharp AS, Gerber R, Talwar S, Assomull R, Cole G, Keenan NG, Kanaganayagam G, Sehmi J, Wensel R, Harrell FE, Mayet J, Thom S, Davies JE, Francis DP. Dobutamine Stress Echocardiography Ischemia as a Predictor of the Placebo-Controlled Efficacy of Percutaneous Coronary Intervention in Stable Coronary Artery Disease: The Stress Echocardiography-Stratified Analysis of ORBITA. Circulation 2019; 140:1971-1980. [PMID: 31707827 PMCID: PMC6903430 DOI: 10.1161/circulationaha.119.042918] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
BACKGROUND Dobutamine stress echocardiography is widely used to test for ischemia in patients with stable coronary artery disease. In this analysis, we studied the ability of the prerandomization stress echocardiography score to predict the placebo-controlled efficacy of percutaneous coronary intervention (PCI) within the ORBITA trial (Objective Randomised Blinded Investigation With Optimal Medical Therapy of Angioplasty in Stable Angina). METHODS One hundred eighty-three patients underwent dobutamine stress echocardiography before randomization. The stress echocardiography score is broadly the number of segments abnormal at peak stress, with akinetic segments counting double and dyskinetic segments counting triple. The ability of prerandomization stress echocardiography to predict the placebo-controlled effect of PCI on response variables was tested by using regression modeling. RESULTS At prerandomization, the stress echocardiography score was 1.56±1.77 in the PCI arm (n=98) and 1.61±1.73 in the placebo arm (n=85). There was a detectable interaction between prerandomization stress echocardiography score and the effect of PCI on angina frequency score with a larger placebo-controlled effect in patients with the highest stress echocardiography score (Pinteraction=0.031). With our sample size, we were unable to detect an interaction between stress echocardiography score and any other patient-reported response variables: freedom from angina (Pinteraction=0.116), physical limitation (Pinteraction=0.461), quality of life (Pinteraction=0.689), EuroQOL 5 quality-of-life score (Pinteraction=0.789), or between stress echocardiography score and physician-assessed Canadian Cardiovascular Society angina class (Pinteraction=0.693), and treadmill exercise time (Pinteraction=0.426). CONCLUSIONS The degree of ischemia assessed by dobutamine stress echocardiography predicts the placebo-controlled efficacy of PCI on patient-reported angina frequency. The greater the downstream stress echocardiography abnormality caused by a stenosis, the greater the reduction in symptoms from PCI. CLINICAL TRIAL REGISTRATION URL: https://www.clinicaltrials.gov. Unique identifier: NCT02062593.
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Ahmad Y, Vendrik J, Eftekhari A, Howard JP, Cook C, Rajkumar C, Malik I, Mikhail G, Ruparelia N, Hadjiloizou N, Nijjer S, Al-Lamee R, Petraco R, Warisawa T, Wijntjens GWM, Koch KT, van de Hoef T, de Waard G, Echavarria-Pinto M, Frame A, Sutaria N, Kanaganayagam G, Ariff B, Anderson J, Chukwuemeka A, Fertleman M, Koul S, Iglesias JF, Francis D, Mayet J, Serruys P, Davies J, Escaned J, van Royen N, Götberg M, Juhl Terkelsen C, Høj Christiansen E, Piek JJ, Baan J, Sen S. Determining the Predominant Lesion in Patients With Severe Aortic Stenosis and Coronary Stenoses: A Multicenter Study Using Intracoronary Pressure and Flow. Circ Cardiovasc Interv 2019; 12:e008263. [PMID: 31752515 PMCID: PMC6924937 DOI: 10.1161/circinterventions.119.008263] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Patients with severe aortic stenosis (AS) often have coronary artery disease. Both the aortic valve and the coronary disease influence the blood flow to the myocardium and its ability to respond to stress; leading to exertional symptoms. In this study, we aim to quantify the effect of severe AS on the coronary microcirculation and determine if this is influenced by any concomitant coronary disease. We then compare this to the effect of coronary stenoses on the coronary microcirculation.
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Al-Lamee R, Howard JP, Shun-Shin MJ, Thompson D, Dehbi HM, Sen S, Nijjer S, Petraco R, Davies J, Keeble T, Tang K, Malik IS, Cook C, Ahmad Y, Sharp ASP, Gerber R, Baker C, Kaprielian R, Talwar S, Assomull R, Cole G, Keenan NG, Kanaganayagam G, Sehmi J, Wensel R, Harrell FE, Mayet J, Thom SA, Davies JE, Francis DP. Fractional Flow Reserve and Instantaneous Wave-Free Ratio as Predictors of the Placebo-Controlled Response to Percutaneous Coronary Intervention in Stable Single-Vessel Coronary Artery Disease. Circulation 2019; 138:1780-1792. [PMID: 29789302 DOI: 10.1161/circulationaha.118.033801] [Citation(s) in RCA: 77] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
BACKGROUND There are no data on how fractional flow reserve (FFR) and instantaneous wave-free ratio (iFR) are associated with the placebo-controlled efficacy of percutaneous coronary intervention (PCI) in stable single-vessel coronary artery disease. METHODS We report the association between prerandomization invasive physiology within ORBITA (Objective Randomised Blinded Investigation With Optimal Medical Therapy of Angioplasty in Stable Angina), a placebo-controlled trial of patients who have stable angina with angiographically severe single-vessel coronary disease clinically eligible for PCI. Patients underwent prerandomization research FFR and iFR assessment. The operator was blinded to these values. Assessment of response variables, treadmill exercise time, stress echocardiography score, symptom frequency, and angina severity were performed at prerandomization and blinded follow-up. Effects were calculated by analysis of covariance. The ability of FFR and iFR to predict placebo-controlled changes in response variables was tested by using regression modeling. RESULTS Invasive physiology data were available in 196 patients (103 PCI and 93 placebo). At prerandomization, the majority had Canadian Cardiovascular Society class II or III symptoms (150/196, 76.5%). Mean FFR and iFR were 0.69±0.16 and 0.76±0.22, respectively; 97% had ≥1 positive ischemia tests. The estimated effect of PCI on between-arm prerandomization-adjusted total exercise time was 20.7 s (95% confidence interval [CI], -4.0 to 45.5; P=0.100) with no interaction of FFR ( Pinteraction=0.318) or iFR ( Pinteraction=0.523). PCI improved stress echocardiography score more than placebo (1.07 segment units; 95% CI, 0.70-1.44; P<0.00001). The placebo-controlled effect of PCI on stress echocardiography score increased progressively with decreasing FFR ( Pinteraction<0.00001) and decreasing iFR ( Pinteraction<0.00001). PCI did not improve angina frequency score significantly more than placebo (odds ratio, 1.64; 95% CI, 0.96-2.80; P=0.072) with no detectable evidence of interaction with FFR ( Pinteraction=0.849) or iFR ( Pinteraction=0.783). However, PCI resulted in more patient-reported freedom from angina than placebo (49.5% versus 31.5%; odds ratio, 2.47; 95% CI, 1.30-4.72; P=0.006) but neither FFR ( Pinteraction=0.693) nor iFR ( Pinteraction=0.761) modified this effect. CONCLUSIONS In patients with stable angina and severe single-vessel disease, the blinded effect of PCI was more clearly seen by stress echocardiography score and freedom from angina than change in treadmill exercise time. Moreover, the lower the FFR or iFR, the greater the magnitude of stress echocardiographic improvement caused by PCI. CLINICAL TRIAL REGISTRATION URL: https://www.clinicaltrials.gov . Unique identifier: NCT02062593.
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Cook CM, Petraco R, Shun-Shin MJ, Ahmad Y, Nijjer S, Al-Lamee R, Kikuta Y, Shiono Y, Mayet J, Francis DP, Sen S, Davies JE. Diagnostic Accuracy of Computed Tomography-Derived Fractional Flow Reserve : A Systematic Review. JAMA Cardiol 2019; 2:803-810. [PMID: 28538960 DOI: 10.1001/jamacardio.2017.1314] [Citation(s) in RCA: 145] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Importance Computed tomography-derived fractional flow reserve (FFR-CT) is a novel, noninvasive test for myocardial ischemia. Clinicians using FFR-CT must be able to interpret individual FFR-CT results to determine subsequent patient care. Objective To provide clinicians a means of interpreting individual FFR-CT results with respect to the range of invasive FFRs that this interpretation might likely represent. Evidence Review We performed a systematic review in accordance with guidelines from the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. A systematic search of MEDLINE (January 1, 2011, to 2016, week 2) and EMBASE (January 1, 2011, to 2016, week 2) was performed for studies assessing the diagnostic accuracy of FFR-CT. Title words used were computed tomography or computed tomographic and fractional flow reserve or FFR. Results were limited to publications in peer-reviewed journals. Duplicate studies and abstracts from scientific meetings were removed. All of the retrieved studies, including references, were reviewed. Findings There were 908 vessels from 536 patients in 5 studies included in the analysis. A total of 365 (68.1%) were male, and the mean (SD) age was 63.2 (9.5) years. The overall per-vessel diagnostic accuracy of FFR-CT was 81.9% (95% CI, 79.4%-84.4%). For vessels with FFR-CT values below 0.60, 0.60 to 0.70, 0.70 to 0.80, 0.80 to 0.90, and above 0.90, diagnostic accuracy of FFR-CT was 86.4% (95% CI, 78.0%-94.0%), 74.7% (95% CI, 71.9%-77.5%), 46.1% (95% CI, 42.9%-49.3%), 87.3% (95% CI, 85.1%-89.5%), and 97.9% (95% CI, 97.9%-98.8%), respectively. The 82% (overall) diagnostic accuracy threshold was met for FFR-CT values lower than 0.63 or above 0.83. More stringent 95% and 98% diagnostic accuracy thresholds were met for FFR-CT values lower than 0.53 or above 0.93 and lower than 0.47 or above 0.99, respectively. Conclusions and Relevance The diagnostic accuracy of FFR-CT varies markedly across the spectrum of disease. This analysis allows clinicians to interpret the diagnostic accuracy of individual FFR-CT results. In combination with patient-specific factors, clinicians can use FFR-CT to judge when the cost and risk of an invasive angiogram may safely be avoided.
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Cook CM, Ahmad Y, Howard JP, Shun-Shin MJ, Sethi A, Clesham GJ, Tang KH, Nijjer SS, Kelly PA, Davies JR, Malik IS, Kaprielian R, Mikhail G, Petraco R, Warisawa T, Al-Janabi F, Karamasis GV, Mohdnazri S, Gamma R, de Waard GA, Al-Lamee R, Keeble TR, Mayet J, Sen S, Francis DP, Davies JE. Association Between Physiological Stenosis Severity and Angina-Limited Exercise Time in Patients With Stable Coronary Artery Disease. JAMA Cardiol 2019; 4:569-574. [PMID: 31042268 PMCID: PMC6495364 DOI: 10.1001/jamacardio.2019.1139] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Importance Physiological stenosis assessment is recommended to guide percutaneous coronary intervention (PCI) in patients with stable angina. Objective To determine the association between all commonly used indices of physiological stenosis severity and angina-limited exercise time in patients with stable angina. Design, Setting, and Participants This cohort study included data (without follow-up) collected over 1 year from 2 cardiac hospitals. Selected patients with stable angina and physiologically severe single-vessel coronary artery disease presenting for clinically driven elective PCI were included. Exposures Fractional flow reserve (FFR), instantaneous wave-free ratio (iFR), hyperemic stenosis resistance (HSR), and coronary flow reserve (CFR) were measured invasively. Immediately after this, patients maximally exercised on a catheter-table-mounted supine ergometer until they developed rate-limiting angina. Subsequent PCI was performed in most patients, followed by repeat maximal supine exercise testing. Main Outcomes and Measures Associations between FFR, iFR, HSR, CFR, and angina-limited exercise time were assessed using linear regression and Pearson correlation coefficients. Additionally, the associations between the post-PCI increment in exercise time and baseline FFR, iFR, HSR, and CFR were assessed. Results Twenty-three patients (21 [91.3%] of whom were male; mean [SD] age, 60.6 [8.1] years) completed the pre-PCI component of the study protocol. Mean (SD) stenosis diameter was 74.6% (10.4%). Median (interquartile range [IQR]) values were 0.54 (0.44-0.72) for FFR, 0.53 (0.38-0.83) for iFR, 1.67 (0.84-3.16) for HSR, and 1.35 (1.11-1.63) for CFR. Mean (SD) angina-limited exercise time was 144 (77) seconds. Anatomical stenosis characteristics were not significantly associated with angina-limited exercise time. Conversely, FFR (R2 = 0.27; P = .01), iFR (R2 = 0.46; P < .001), HSR (R2 = 0.39; P < .01), and CFR (R2 = 0.16; P < .05) were all associated with angina-limited exercise time. Twenty-one patients (19 [90.5%] of whom were male; mean [SD] age, 60.1 [8.2] years) competed the full protocol of PCI, post-PCI physiological assessment, and post-PCI maximal exercise. After PCI, the median (IQR) FFR rose to 0.91 (0.85-0.96), median (IQR) iFR to 0.98 (0.94-0.99), and median (IQR) CFR to 2.73 (2.50-3.12), while the median (IQR) HSR fell to 0.16 (0.06-0.37) (P < .001 for all). The post-PCI increment in exercise time was most significantly associated with baseline iFR (R2 = 0.26; P = .02). Conclusions and Relevance In a selected group of patients with severe, single-vessel stable angina, FFR, iFR, HSR, and CFR were all modestly correlated with angina-limited exercise time to varying degrees. Notwithstanding the limited sample size, no clear association was demonstrated between anatomical stenosis severity and angina-limited exercise time.
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Ahmad Y, Al-Lamee R, Davies J, Sen S. A case report of the clinical effect of chronic total occlusion recanalization on the instantaneous wave-free ratio in the donor artery. EUROPEAN HEART JOURNAL-CASE REPORTS 2019; 2:1-4. [PMID: 31020109 PMCID: PMC6177112 DOI: 10.1093/ehjcr/yty014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Accepted: 01/03/2018] [Indexed: 01/10/2023]
Abstract
Introduction Coronary physiology is recommended for guiding percutaneous coronary intervention (PCI). Previous cases have demonstrated changes in fractional flow reserve in a donor collateral vessel after PCI to a chronic total occlusion (CTO). The behaviour of instantaneous wave-free ratio (iFR) in the context of CTO has not been described. Case presentation In this case, we share the first case of the effect of CTO recanalization on iFR in the donor artery, and show how iFR can reflect the amount of myocardium subtended by a stenosis. Discussion Instantaneous wave-free ratio is able to incorporate the amount of subtended myocardium in its quantification of coronary stenosis severity.
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Howard JP, Fisher L, Shun-Shin MJ, Keene D, Arnold AD, Ahmad Y, Cook CM, Moon JC, Manisty CH, Whinnett ZI, Cole GD, Rueckert D, Francis DP. Cardiac Rhythm Device Identification Using Neural Networks. JACC Clin Electrophysiol 2019; 5:576-586. [PMID: 31122379 PMCID: PMC6537849 DOI: 10.1016/j.jacep.2019.02.003] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Revised: 01/16/2019] [Accepted: 02/14/2019] [Indexed: 11/02/2022]
Abstract
OBJECTIVES This paper reports the development, validation, and public availability of a new neural network-based system which attempts to identify the manufacturer and even the model group of a pacemaker or defibrillator from a chest radiograph. BACKGROUND Medical staff often need to determine the model of a pacemaker or defibrillator (cardiac rhythm device) quickly and accurately. Current approaches involve comparing a device's radiographic appearance with a manual flow chart. METHODS In this study, radiographic images of 1,676 devices, comprising 45 models from 5 manufacturers were extracted. A convolutional neural network was developed to classify the images, using a training set of 1,451 images. The testing set contained an additional 225 images consisting of 5 examples of each model. The network's ability to identify the manufacturer of a device was compared with that of cardiologists, using a published flowchart. RESULTS The neural network was 99.6% (95% confidence interval [CI]: 97.5% to 100.0%) accurate in identifying the manufacturer of a device from a radiograph and 96.4% (95% CI: 93.1% to 98.5%) accurate in identifying the model group. Among 5 cardiologists who used the flowchart, median identification of manufacturer accuracy was 72.0% (range 62.2% to 88.9%), and model group identification was not possible. The network's ability to identify the manufacturer of the devices was significantly superior to that of all the cardiologists (p < 0.0001 compared with the median human identification; p < 0.0001 compared with the best human identification). CONCLUSIONS A neural network can accurately identify the manufacturer and even model group of a cardiac rhythm device from a radiograph and exceeds human performance. This system may speed up the diagnosis and treatment of patients with cardiac rhythm devices, and it is publicly accessible online.
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Warisawa T, Howard JP, Cook C, Ahmad Y, Doi S, Nakayama M, Goto S, Yakuta Y, Karube K, Seike F, Uetani T, Murai T, Kikuta Y, Shiono Y, Kawase Y, Kaihara T, Higuma T, Ishibashi Y, Matsuda H, Nishina H, Matsuo H, Escaned J, Francis D, Akashi Y, Davies J. INTER-OBSERVER DIFFERENCES IN INTERPRETATION OF PRESSURE-WIRE PULLBACK TRACES. J Am Coll Cardiol 2019. [DOI: 10.1016/s0735-1097(19)32023-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Sen S, Ahmad Y, Dehbi HM, Howard JP, Iglesias JF, Al-Lamee R, Petraco R, Nijjer S, Bhindi R, Lehman S, Walters D, Sapontis J, Janssens L, Vrints CJ, Khashaba A, Laine M, Van Belle E, Krackhardt F, Bojara W, Going O, Härle T, Indolfi C, Niccoli G, Ribichini F, Tanaka N, Yokoi H, Takashima H, Kikuta Y, Erglis A, Vinhas H, Silva PC, Baptista SB, Alghamdi A, Hellig F, Koo BK, Nam CW, Shin ES, Doh JH, Brugaletta S, Alegria-Barrero E, Meuwissen M, Piek JJ, van Royen N, Sezer M, Di Mario C, Gerber RT, Malik IS, Sharp ASP, Talwar S, Tang K, Samady H, Altman J, Seto AH, Singh J, Jeremias A, Matsuo H, Kharbanda RK, Patel MR, Serruys P, Escaned J, Davies JE. Clinical Events After Deferral of LAD Revascularization Following Physiological Coronary Assessment. J Am Coll Cardiol 2019; 73:444-453. [PMID: 30704577 PMCID: PMC6354033 DOI: 10.1016/j.jacc.2018.10.070] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Revised: 10/04/2018] [Accepted: 10/22/2018] [Indexed: 01/10/2023]
Abstract
BACKGROUND Physicians are not always comfortable deferring treatment of a stenosis in the left anterior descending (LAD) artery because of the perception that there is a high risk of major adverse cardiac events (MACE). The authors describe, using the DEFINE-FLAIR (Functional Lesion Assessment of Intermediate Stenosis to Guide Revascularisation) trial, MACE rates when LAD lesions are deferred, guided by physiological assessment using fractional flow reserve (FFR) or the instantaneous wave-free ratio (iFR). OBJECTIVES The purpose of this study was to establish the safety of deferring treatment in the LAD using FFR or iFR within the DEFINE-FLAIR trial. METHODS MACE rates at 1 year were compared between groups (iFR and FFR) in patients whose physiological assessment led to LAD lesions being deferred. MACE was defined as a composite of cardiovascular death, myocardial infarction (MI), and unplanned revascularization at 1 year. Patients, and staff performing follow-up, were blinded to whether the decision was made with FFR or iFR. Outcomes were adjusted for age and sex. RESULTS A total of 872 patients had lesions deferred in the LAD (421 guided by FFR, 451 guided by iFR). The event rate with iFR was significantly lower than with FFR (2.44% vs. 5.26%; adjusted HR: 0.46; 95% confidence interval [CI]: 0.22 to 0.95; p = 0.04). This was driven by significantly lower unplanned revascularization with iFR and numerically lower MI (unplanned revascularization: 2.22% iFR vs. 4.99% FFR; adjusted HR: 0.44; 95% CI: 0.21 to 0.93; p = 0.03; MI: 0.44% iFR vs. 2.14% FFR; adjusted HR: 0.23; 95% CI: 0.05 to 1.07; p = 0.06). CONCLUSIONS iFR-guided deferral appears to be safe for patients with LAD lesions. Patients in whom iFR-guided deferral was performed had statistically significantly lower event rates than those with FFR-guided deferral.
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Veltman K, Harris C, Ahmad Y, Jolliet O. A mechanistic model for thiol redox dynamics in the organogenesis stage rat conceptus. Reprod Toxicol 2018; 82:38-49. [PMID: 30292673 PMCID: PMC9999374 DOI: 10.1016/j.reprotox.2018.09.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Revised: 08/07/2018] [Accepted: 09/19/2018] [Indexed: 11/17/2022]
Abstract
Precise control of the glutathione/glutathione disulfide (GSH/GSSG) redox balance is vital for the developing embryo, but regulatory mechanisms are poorly understood. We developed a novel, mechanistic mass-balance model for GSH metabolism in the organogenesis stage (gestational day 10.0-11.13) rat conceptus predicting the dynamics of 8 unique metabolites in 3 conceptal compartments: the visceral yolk sac (VYS), the extra-embryonic fluid (EEF) and the embryo proper (EMB). Our results show that thiol concentrations in all compartments are well predicted by the model. Protein synthesis is predicted to be a major efflux pathway for all amino acid precursors of GSH synthesis and an essential model element. Our model provides quantitative insights in the transport fluxes and enzymatic fluxes needed to maintain thiol redox balances under normal physiological conditions. This is crucial to further elucidate the mechanisms through which chemical exposure can perturb redox homeostasis, causing oxidative stress, and potentially birth defects.
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