Left atrial strain is a good predictor of atrio-ventricular synchrony in leadless pacemaker pacing.

INTRODUCTION: The importance of atrio-ventricular synchrony pacing in sinus rhythm patients is known. To identify patients in whom leadless pacemakers are able to guarantee this atrio-ventricular synchrony, we explored correlations among echocardiographic measures of left atrial (LA) size and function (doppler parameter and strain) with A4 amplitude in patients implanted with new generation Micra-AV device. METHODS: After implantation with Micra-AV system, patients underwent device interrogation to evaluate AV synchrony based on the sensing of atrial mechanics and echocardiographic exam to assess LA morphology and LA function. RESULTS: In the 21 studied patients (14 males, 72 ± 13 years), the A4 wave amplitude values inversely correlated with LA antero-posterior diameter, LA volume, LA contraction strain and LA conduit strain, while they were positively related with LA reservoir strain. DISCUSSION: Our results indicate a statistically significant relationship between morphological echocardiographic LA parameters and atrial contraction signal (A4), detected by leadless pacemakers and used to synchronize ventricular pacing with the atrium. Instantaneous LA function assessment obtained with LA strain provides incremental information over morphological parameters. LA strain evaluates atrial myocardial deformation during the whole cardiac cycle. We found higher value of A4 in patients that have grater absolute value of LAsr, LAscd and LAsct, that are simple and measurable parameters of LA functional capacity. CONCLUSION: Preimplant echocardiographic evaluation of the atrial contractility may be useful in predicting adequate A4 sensing and consequently a good atrio-ventricular synchrony pacing. Echocardiography LA strain study seems promising in Micra-AV patient selection.

AI Cardiac MRI Scar Analysis Aids Prediction of Major Arrhythmic Events in the Multicenter DERIVATE Registry.

Background Scar burden with late gadolinium enhancement (LGE) cardiac MRI (CMR) predicts arrhythmic events in patients with postinfarction in single-center studies. However, LGE analysis requires experienced human observers, is time consuming, and introduces variability. Purpose To test whether postinfarct scar with LGE CMR can be quantified fully automatically by machines and to compare the ability of LGE CMR scar analyzed by humans and machines to predict arrhythmic events. Materials and Methods This study is a retrospective analysis of the multicenter, multivendor CarDiac MagnEtic Resonance for Primary Prevention Implantable CardioVerter DebrillAtor ThErapy (DERIVATE) registry. Patients with chronic heart failure, echocardiographic left ventricular ejection fraction (LVEF) of less than 50%, and LGE CMR were recruited (from January 2015 through December 2020). In the current study, only patients with ischemic cardiomyopathy were included. Quantification of total, dense, and nondense scars was carried out by two experienced readers or a Ternaus network, trained and tested with LGE images of 515 and 246 patients, respectively. Univariable and multivariable Cox analyses were used to assess patient and cardiac characteristics associated with a major adverse cardiac event (MACE). Area under the receiver operating characteristic curve (AUC) was used to compare model performances. Results In 761 patients (mean age, 65 years ± 11, 671 men), 83 MACEs occurred. With use of the testing group, univariable Cox-analysis found New York Heart Association class, left ventricle volume and/or function parameters (by echocardiography or CMR), guideline criterion (LVEF of ≤35% and New York Heart Association class II or III), and LGE scar analyzed by humans or the machine-learning algorithm as predictors of MACE. Machine-based dense or total scar conferred incremental value over the guideline criterion for the association with MACE (AUC: 0.68 vs 0.63, P = .02 and AUC: 0.67 vs 0.63, P = .01, respectively). Modeling with competing risks yielded for dense and total scar (AUC: 0.67 vs 0.61, P = .01 and AUC: 0.66 vs 0.61, P = .005, respectively). Conclusion In this analysis of the multicenter CarDiac MagnEtic Resonance for Primary Prevention Implantable CardioVerter DebrillAtor ThErapy (DERIVATE) registry, fully automatic machine learning-based late gadolinium enhancement analysis reliably quantifies myocardial scar mass and improves the current prediction model that uses guideline-based risk criteria for implantable cardioverter defibrillator implantation. ClinicalTrials.gov registration no.: NCT03352648 Published under a CC BY 4.0 license. Supplemental material is available for this article.

Cardiac computed tomography: from anatomy to function.

Ischaemic heart disease (IHD) is one of the world's leading causes of morbidity and mortality. Likewise, the diagnosis and risk stratification of patients with coronary artery disease (CAD) have always been based on the detection of the presence and extent of ischaemia by physical or pharmacological stress tests with or without the aid of imaging methods (e.g. exercise stress, test, stress echocardiography, single-photon emission computed tomography, or stress cardiac magnetic resonance). These methods show high performance to assess obstructive CAD, whilst they do not show accurate power to detect non-obstructive CAD. The introduction into clinical practice of coronary computed tomography angiography, the only non-invasive method capable of analyzing the coronary anatomy, allowed to add a crucial piece in the puzzle of the assessment of patients with suspected or chronic IHD. The current review evaluates the technical aspects and clinical experience of coronary computed tomography in the evaluation of atherosclerotic burden with a special focus about the new emerging application such as functional relevance of CAD with fractional flow reserve computed tomography (CT)-derived (FFRct), stress CT perfusion, and imaging inflammatory makers discussing the strength and weakness of each approach.

T1 mapping and cardiac magnetic resonance feature tracking in mitral valve prolapse.

OBJECTIVES: T1 mapping (T1-map) and cardiac magnetic resonance feature tracking (CMR-FT) techniques have been introduced for the early detection of interstitial myocardial fibrosis and deformation abnormalities. We sought to demonstrate that T1-map and CMR-FT may identify the presence of subclinical myocardial structural changes in patients with mitral valve prolapse (MVP). METHODS: Consecutive MVP patients with moderate-to-severe mitral regurgitation and comparative matched healthy subjects were prospectively enrolled and underwent CMR-FT analysis to calculate 2D global and segmental circumferential (CS) and radial strain (RS) and T1-map to determine global and segmental native T1 (nT1) values. RESULTS: Seventy-three MVP patients (mean age, 57 ± 13 years old; male, 76%; regurgitant volume, 57 ± 21 mL) and 42 matched control subjects (mean age, 56 ± 18 years; male, 74%) were included. MVP patients showed a lower global CS (- 16.3 ± 3.4% vs. - 17.8 ± 1.9%, p = 0.020) and longer global nT1 (1124.9 ± 97.7 ms vs. 1007.4 ± 26.1 ms, p < 0.001) as compared to controls. Moreover, MVP patients showed lower RS and CS in basal (21.6 ± 12.3% vs. 27.6 ± 8.9%, p = 0.008, and - 13.0 ± 6.7% vs. - 14.9 ± 4.1%, p = 0.013) and mid-inferolateral (20.6 ± 10.7% vs. 28.4 ± 8.7%, p < 0.001, and - 12.8 ± 6.3% vs. - 16.5 ± 4.0%, p < 0.001) walls as compared to other myocardial segments. Similarly, MVP patients showed longer nT1 values in basal (1080 ± 68 ms vs. 1043 ± 43 ms, p < 0.001) and mid-inferolateral (1080 ± 77 ms vs. 1034 ± 37 ms, p < 0.001) walls as compared to other myocardial segments. Of note, nT1 values were significantly correlated with CS (r, 0.36; p < 0.001) and RS (r, 0.37; p < 0.001) but not with regurgitant volume. CONCLUSIONS: T1-map and CMR-FT identify subclinical left ventricle tissue changes in patients with MVP. Further studies are required to correlate these subclinical tissue changes with the outcome. KEY POINTS: • T1 mapping (T1-map) and cardiac magnetic resonance feature tracking (CMR-FT) techniques have been introduced for the early detection of interstitial myocardial fibrosis and deformation abnormalities. • In MVP patients, we demonstrated a longer global nT1 with associated reduced global circumferential (CS) and radial strain (RS) as compared to control subjects. • Among MVP patients, the mid-basal left ventricle inferolateral wall showed longer nT1 with reduced CS and RS as compared to other myocardial segments. Further studies are required to correlate these subclinical tissue changes with the outcome.

Role of Cardiac Magnetic Resonance Imaging in Myocardial Infarction.

PURPOSE OF REVIEW: The purpose of the present paper is to analytically review the diagnostic and prognostic role of CMR in ST-segment elevation myocardial infarction (STEMI) survivors. Percutaneous coronary intervention (PCI) is the treatment of choice in patients STEMI. However, risk of future events remains substantial. Assessment of the extent of myocardial infarction (MI), cardiac function and ventricular remodelling has become the focus of recent studies. Electrocardiography, angiography and echocardiography parameters, as well as risk scores, lack sensitivity and reproducibility in predicting future cardiovascular events. A major advantage of cardiac magnetic resonance imaging (CMR) is that it provides myocardial tissue characterization. RECENT FINDINGS: CMR is able to quantify both reversible and irreversible myocardial injury and correlates with future events. This review will illustrate how microvascular function indices (myocardial salvage index, presence and amount of microvascular obstruction and intramyocardial haemorrhage) detectable by CMR add prognostic information and could impact on future strategies to improve outcomes in revascularized patients.

Impact of an intra-cycle motion correction algorithm on overall evaluability and diagnostic accuracy of computed tomography coronary angiography.

OBJECTIVES: The aim of this study was to evaluate the impact of a novel intra-cycle motion correction algorithm (MCA) on overall evaluability and diagnostic accuracy of cardiac computed tomography coronary angiography (CCT). METHODS: From a cohort of 900 consecutive patients referred for CCT for suspected coronary artery disease (CAD), we enrolled 160 (18 %) patients (mean age 65.3 ± 11.7 years, 101 male) with at least one coronary segment classified as non-evaluable for motion artefacts. The CCT data sets were evaluated using a standard reconstruction algorithm (SRA) and MCA and compared in terms of subjective image quality, evaluability and diagnostic accuracy. RESULTS: The mean heart rate during the examination was 68.3 ± 9.4 bpm. The MCA showed a higher Likert score (3.1 ± 0.9 vs. 2.5 ± 1.1, p < 0.001) and evaluability (94%vs.79 %, p < 0.001) than the SRA. In a 45-patient subgroup studied by clinically indicated invasive coronary angiography, specificity, positive predictive value and accuracy were higher in MCA vs. SRA in segment-based and vessel-based models, respectively (87%vs.73 %, 50%vs.34 %, 85%vs.73 %, p < 0.001 and 62%vs.28 %, 66%vs.51 % and 75%vs.57 %, p < 0.001). In a patient-based model, MCA showed higher accuracy vs. SCA (93%vs.76 %, p < 0.05). CONCLUSIONS: MCA can significantly improve subjective image quality, overall evaluability and diagnostic accuracy of CCT. KEY POINTS: Cardiac computed tomographic coronary angiography (CCT) allows non-invasive evaluation of coronary arteries. Intra-cycle motion correction algorithm (MCA) allows for compensation of coronary motion. An MCA improves image quality, CCT evaluability and diagnostic accuracy.

Inferior ST-Elevation Acute Myocardial Infarction or an Inferior-Lead Brugada-like Electrocardiogram Pattern Associated With the Use of Pregabalin and Quetiapine?

The Brugada electrocardiogram pattern is characterized by coved-type ST-elevation (>2 mm) in the right precordial leads. We report the case of a 62-year-old man, with bipolar disorder, admitted to the emergency department because of dyspnea and chest discomfort. The patient was on treatment with pregabalin and quetiapine. Unexpectedly, electrocardiogram at admission showed diffuse ST-elevation, more evident in inferior leads, where a Brugada-like pattern was present. The patient underwent coronary angiography with a diagnosis of suspected acute coronary syndrome. Coronary angiography, however, showed mild coronary artery disease not requiring coronary angioplasty. Echocardiography did not reveal left ventricular dysfunction or pericardial effusion. Troponin levels remained normal over serial controls. Eventually, chest radiography showed lung opacities and consolidation suggestive for pneumonia. To the best of our knowledge, this is one of the first cases showing a transient Brugada-like electrocardiogram pattern in inferior leads, probably amplified by the administration of pregabalin and quetiapine.

Left and right ventricle assessment with Cardiac CT: validation study vs. Cardiac MR.

OBJECTIVES: To compare Magnetic Resonance (MR) and Computed Tomography (CT) for the assessment of left (LV) and right (RV) ventricular functional parameters. METHODS: Seventy nine patients underwent both Cardiac CT and Cardiac MR. Images were acquired using short axis (SAX) reconstructions for CT and 2D cine b-SSFP (balanced-steady state free precession) SAX sequence for MR, and evaluated using dedicated software. RESULTS: CT and MR images showed good agreement: LV EF (Ejection Fraction) (52 ± 14% for CT vs. 52 ± 14% for MR; r = 0.73; p > 0.05); RV EF (47 ± 12% for CT vs. 47 ± 12% for MR; r = 0.74; p > 0.05); LV EDV (End Diastolic Volume) (74 ± 21 ml/m² for CT vs. 76 ± 25 ml/m² for MR; r = 0.59; p > 0.05); RV EDV (84 ± 25 ml/m² for CT vs. 80 ± 23 ml/m² for MR; r = 0.58; p > 0.05); LV ESV (End Systolic Volume)(37 ± 19 ml/m² for CT vs. 38 ± 23 ml/m² for MR; r = 0.76; p > 0.05); RV ESV (46 ± 21 ml/m² for CT vs. 43 ± 18 ml/m² for MR; r = 0.70; p > 0.05). Intra- and inter-observer variability were good, and the performance of CT was maintained for different EF subgroups. CONCLUSIONS: Cardiac CT provides accurate and reproducible LV and RV volume parameters compared with MR, and can be considered as a reliable alternative for patients who are not suitable to undergo MR. KEY POINTS: • Cardiac-CT is able to provide Left and Right Ventricular function. • Cardiac-CT is accurate as MR for LV and RV volume assessment. • Cardiac-CT can provide accurate evaluation of coronary arteries and LV and RV function.

Stress CMR in Known or Suspected CAD: Diagnostic and Prognostic Role.

The recently published 2019 guidelines on chronic coronary syndromes (CCS) focus on the need for noninvasive imaging modalities to accurately establish the diagnosis of coronary artery disease (CAD) and assess the risk of clinical scenario occurrence. Appropriate patient management should rely on controlling symptoms, improving prognosis, and guiding each therapeutic strategy as well as monitoring disease progress. Among the noninvasive imaging modalities, cardiovascular magnetic resonance (CMR) has gained broad acceptance in past years due to its unique features in providing a complete assessment of CAD through data on cardiac anatomy and function and myocardial viability, with high spatial and temporal resolution and without ionizing radiation. In detail, evaluation of the presence and extent of myocardial ischemia through stress CMR (S-CMR) has shown a high rule-in power in detecting functionally significant coronary artery stenosis in patients suspected of CCS. Moreover, S-CMR technique may add significant prognostic value, as demonstrated by different studies which have progressively evidenced the valuable power of this multiparametric imaging modality in predicting adverse cardiac events. The latest scientific progress supports a greater expansion of S-CMR with improvement of quantitative myocardial perfusion analysis, myocardial strain, and native mapping within the same examination. Although further study is warranted, these techniques, which are currently mostly restricted to the research field, are likely to become increasingly prevalent in the clinical setting with the scope of increasing accuracy in the selection of patients to be sent to invasive revascularization. This review investigates the diagnostic and prognostic role of S-CMR in the context of CAD, by analysing a strong, long-standing, scientific evidence together with an appraisal of new advanced techniques which may potentially enrich CAD management in the next future.

Role of computed tomography in COVID-19.

Coronavirus disease 2019 (COVID-19) has become a rapid worldwide pandemic. While COVID-19 primarily manifests as an interstitial pneumonia and severe acute respiratory distress syndrome, severe involvement of other organs has been documented. In this article, we will review the role of non-contrast chest computed tomography in the diagnosis, follow-up and prognosis of patients affected by COVID-19 pneumonia with a detailed description of the imaging findings that may be encountered. Given that patients with COVID-19 may also suffer from coagulopathy, we will discuss the role of CT pulmonary angiography in the detection of acute pulmonary embolism. Finally, we will describe more advanced applications of CT in the differential diagnosis of myocardial injury with an emphasis on ruling out acute coronary syndrome and myocarditis.

Artificial Intelligence in Coronary Computed Tomography Angiography: From Anatomy to Prognosis.

Cardiac computed tomography angiography (CCTA) is widely used as a diagnostic tool for evaluation of coronary artery disease (CAD). Despite the excellent capability to rule-out CAD, CCTA may overestimate the degree of stenosis; furthermore, CCTA analysis can be time consuming, often requiring advanced postprocessing techniques. In consideration of the most recent ESC guidelines on CAD management, which will likely increase CCTA volume over the next years, new tools are necessary to shorten reporting time and improve the accuracy for the detection of ischemia-inducing coronary lesions. The application of artificial intelligence (AI) may provide a helpful tool in CCTA, improving the evaluation and quantification of coronary stenosis, plaque characterization, and assessment of myocardial ischemia. Furthermore, in comparison with existing risk scores, machine-learning algorithms can better predict the outcome utilizing both imaging findings and clinical parameters. Medical AI is moving from the research field to daily clinical practice, and with the increasing number of CCTA examinations, AI will be extensively utilized in cardiac imaging. This review is aimed at illustrating the state of the art in AI-based CCTA applications and future clinical scenarios.

The Incremental Role of Coronary Computed Tomography in Chronic Coronary Syndromes.

In the context of chronic coronary syndromes (CCS), coronary computed tomography angiography (CCTA) has gained broad acceptance as a noninvasive anatomical imaging tool with ability of excluding coronary stenosis with strong negative predictive value. Atherosclerotic plaque lesions are independent predictors of cardiovascular outcomes in high risk patients with known coronary artery disease (CAD). Calcium detection is commonly expressed through the coronary artery calcium score (CACS), but further research is warranted to confirm the powerness of a CACS-only strategy in both diagnosis and prognosis assessment. Recent studies evidence how defined plaque composition characteristics effectively relate to the risk of plaque instabilization and the overall ischemic burden. Fractional flow reserve from CCTA (FFR-CT) has been demonstrated as a reliable method for noninvasive functional evaluation of coronary lesions severity, while the assessment of perfusion imaging under stress conditions is growing as a useful tool for assessment of myocardial ischemia. Moreover, specific applications in procedural planning of transcatheter valve substitution and follow-up of heart transplantation have gained recent importance. This review illustrates the incremental role of CCTA, which can potentially revolutionize the diagnosis and management pathway within the wide clinical spectrum of CCS.

Diagnostic performance of non-invasive imaging for stable coronary artery disease: A meta-analysis.

BACKGROUND: To determine diagnostic performance of non-invasive tests using invasive fractional flow reserve (FFR) as reference standard for coronary artery disease (CAD). METHODS: Medline, Embase, and citations of articles, guidelines, and reviews for studies were used to compare non-invasive tests with invasive FFR for suspected CAD published through March 2017. RESULTS: Seventy-seven studies met inclusion criteria. The diagnostic test with the highest sensitivity to detect a functionally significant coronary lesion was coronary computed tomography (CT) angiography [88%(85%-90%)], followed by FFR derived from coronary CT angiography (FFRCT) [85%(81%-88%)], positron emission tomography (PET) [85%(82%-88%)], stress cardiac magnetic resonance (stress CMR) [81%(79%-84%)], stress myocardial CT perfusion combined with coronary CT angiography [79%(74%-83%)], stress myocardial CT perfusion [77%(73%-80%)], stress echocardiography (Echo) [72%(64%-78%)] and stress single-photon emission computed tomography (SPECT) [64%(60%-68%)]. Specificity to rule out CAD was highest for stress myocardial CT perfusion added to coronary CT angiography [91%(88%-93%)], stress CMR [91%(90%-93%)], and PET [87%(86%-89%)]. CONCLUSION: A negative coronary CT angiography has a higher test performance than other index tests to exclude clinically-important CAD. A positive stress myocardial CT perfusion added to coronary CT angiography, stress cardiac MR, and PET have a higher test performance to identify patients requiring invasive coronary artery evaluation.

Image Quality and Reliability of a Novel Dark-Blood Late Gadolinium Enhancement Sequence in Ischemic Cardiomyopathy.

PURPOSE: The aim of this study was to assess the reliability of a 2D dark-blood phase-sensitive late gadolinium enhancement sequence (2D-DBPSLGE) compared with 2D phase-sensitive inversion recovery late gadolinium enhancement sequence (2D-BBPSLGE) in patients with ischemic cardiomyopathy (ICM). MATERIALS AND METHODS: A total of 73 patients with a clinical history of ICM were prospectively enrolled. The following endpoints were evaluated: (a) comparison of image quality between 2D-BBPSLGE and 2D-DBPSLGE for differentiation between blood pool-late gadolinium enhancement (LGE), remote myocardium-LGE, and blood pool-remote myocardium; (b) diagnostic accuracy of 2D-DBPSLGE compared with gold standard 2D-BBPSLGE for the evaluation of infarcted segments; (c) diagnostic accuracy of 2D-DBPSLGE for the evaluation of microvascular obstruction (MVO); (d) comparison of transmurality index between 2D-BBPSLGE and 2D-DBPSLGE; (e) comparison of papillary muscle hyperenhancement between 2D-BBPSLGE and 2D-DBPSLGE; inter-reader agreement for depiction of hyperenhanced segments in both LGE sequences. Data were analyzed using paired t test, Wilcoxon test, and McNemar test, and η coefficient and intercorrelation coefficient (ICC). RESULTS: Image quality was superior for 2D-DBPSLGE for differentiation of blood pool-LGE (P<0.001). 2D-DBPSLGE, compared with 2D-BBPSLGE, showed a sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of 96.93%, 99.89%, 99.71%, 98.78, and 99.04%, respectively. Concerning MVO detection, 2D-DBPSLGE showed a sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of 66.67%, 100.00%, 100.00%, 80.95%, and 86.21%, respectively. 2D-DBPSLGE underestimated the transmurality (P=0.007) and identified papillary muscle hyperenhancement (P<0.001). Both LGE sequences showed comparable interobserver agreement for the evaluation of infarcted areas (2D-BBPSLGE: ICC 0.99;2D-DBPSLGE: ICC 0.99). CONCLUSIONS: Compared with 2D-BBPSLGE, 2D-DBPSLGE sequences provide better differentiation between LGE and blood-pool, while underestimating LGE trasmurality and the presence of MVO.

Reliability of single breath hold three-dimensional cine kat-ARC for the assessment of biventricular dimensions and function.

PURPOSE: To assess the accuracy and reproducibility of 3D-cine k-adaptative-t-autocalibrating reconstruction for cartesian sampling (3D cine kat-ARC) for quantification of biventricular volumes, ejection fraction and LV mass in clinical practice. METHOD: 74 patients underwent cardiac magnetic resonance for clinical indications. In the whole population 3D cine kat-ARC and 2D cine bSSFP images were acquired on short axis view. Subsequently, the population was divided in three subgroups (dilated, hypetrophic, other phenotypes). Two experienced observers performed analysis of volumes, biventricular function and left ventricular mass in the overall population and subgroups using an off-line workstation. Statistical analysis was performed using Student's t-test, linear regression and Bland-Altman plot, correlation coefficient η2 and the intraclass correlation coefficient (ICC). A cut-off value of p < 0.05 was considered statistically significant. RESULTS: Biventricular volumes, function and left ventricular mass evaluated with 3D cine kat-ARC sequences did not show any significant difference compared to 2D bSSFP sequences in the overall population (p > 0.05). Bland-Altman analysis showed limited bias and narrow limits of the agreement for all measurements in overall population. Subgroup analysis showed a statistically significant difference (p = 0.04) for left ventricular ejection fraction (LVEF) in patients with a dilated phenotype; showing a minimum overestimation tendency for 3D cine kat ARC (2D cine bSSFP LVEF = 46.44 ± 15.83% vs 3D cine kat-ARC LVEF = 48.36 ± 16.50 %). CONCLUSIONS: 3D cine kat-ARC 3D sequences allow an accurate evaluation of biventricular volumes and function in a single breath hold.

Diagnostic Accuracy of Single-shot 2-Dimensional Multisegment Late Gadolinium Enhancement in Ischemic and Nonischemic Cardiomyopathy.

PURPOSE: The aim of this study was to assess the reliability of single-shot 2-dimensional multislice late gadolinium enhancement (2D-MSLGE) compared with gold standard single-slice 2D inversion recovery segmented gradient echo (2D-SSLGE). MATERIALS AND METHODS: Sixty-seven patients prospectively underwent clinically indicated cardiac magnetic resonance (CMR) imaging and were enrolled. The image quality was assessed using a 4-point scale. Segments positive for LGE were classified as ischemic or nonischemic for 2D-MSLGE and 2D-SSLGE. Interobserver and intraobserver variability was assessed for both sequences by 2 readers. The endpoints were as follows: (a) detection of myocardial segments involved by LGE and (b) classification of LGE as ischemic and nonischemic pattern. Sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy value were calculated for the 2 endpoints. RESULTS: 2D-MSLGE and 2D-SSLGE were successfully performed in all patients with comparable image quality (1.56±0.59 vs. 1.54±0.58, P=0.84). For the overall population, 2D-MSLGE correctly identified 1093 of 1139 myocardial segments positive for LGE (96%; 95% confidence interval [CI]: 95%-97%), as compared with 2D-SSLGE. Similarly, 2D-MSLGE correctly identified 1128 of 1139 (99%; 95% CI: 98%-99%) and 1108 of 1139 (97%; 95% CI: 96%-98%) of nonischemic and ischemic LGE patterns.Interobserver and intraobserver variability for quantification of LGE using 2D-MSLGE was 0.98 and 0.99, respectively. The acquisition time was shorter for 2D-MSLGE as compared with 2D-SSLGE (2.0±0.5 vs. 6.0±2.0 min, P: 0.01). CONCLUSIONS: As compared with 2D-SSLGE, 2D-MSLGE is a reliable tool in both ischemic and nonischemic cardiac disease; it is associated with shorter scan times without the need for prolonged breath holding and may be beneficial for those with dysrhythmia.

Performance of a deep learning algorithm for the evaluation of CAD-RADS classification with CCTA.

BACKGROUND AND AIMS: Artificial intelligence (AI) is increasing its role in diagnosis of patients with suspicious coronary artery disease. The aim of this manuscript is to develop a deep convolutional neural network (CNN) to classify coronary computed tomography angiography (CCTA) in the correct Coronary Artery Disease Reporting and Data System (CAD-RADS) category. METHODS: Two hundred eighty eight patients who underwent clinically indicated CCTA were included in this single-center retrospective study. The CCTAs were stratified by CAD-RADS scores by expert readers and considered as reference standard. A deep CNN was designed and tested on the CCTA dataset and compared to on-site reading. The deep CNN analyzed the diagnostic accuracy of the following three Models based on CAD-RADS classification: Model A (CAD-RADS 0 vs CAD-RADS 1-2 vs CAD-RADS 3,4,5), Model 1 (CAD-RADS 0 vs CAD-RADS>0), Model 2 (CAD-RADS 0-2 vs CAD-RADS 3-5). Time of analysis for both physicians and CNN were recorded. RESULTS: Model A showed a sensitivity, specificity, negative predictive value, positive predictive value and accuracy of 47%, 74%, 77%, 46% and 60%, respectively. Model 1 showed a sensitivity, specificity, negative predictive value, positive predictive value and accuracy of 66%, 91%, 92%, 63%, 86%, respectively. Conversely, Model 2 demonstrated the following sensitivity, specificity, negative predictive value, positive predictive value and accuracy: 82%, 58%, 74%, 69%, 71%, respectively. Time of analysis was significantly lower using CNN as compared to on-site reading (530.5 ± 179.1 vs 104.3 ± 1.4 sec, p=0.01) CONCLUSIONS: Deep CNN yielded accurate automated classification of patients with CAD-RADS.

Sequential Strategy Including FFRCT Plus Stress-CTP Impacts on Management of Patients with Stable Chest Pain: The Stress-CTP RIPCORD Study.

Stress computed tomography perfusion (Stress-CTP) and computed tomography-derived fractional flow reserve (FFRCT) are functional techniques that can be added to coronary computed tomography angiography (cCTA) to improve the management of patients with suspected coronary artery disease (CAD). This retrospective analysis from the PERFECTION study aims to assess the impact of their availability on the management of patients with suspected CAD scheduled for invasive coronary angiography (ICA) and invasive FFR. The management plan was defined as optimal medical therapy (OMT) or revascularization and was recorded for the following strategies: cCTA alone, cCTA+FFRCT, cCTA+Stress-CTP and cCTA+FFRCT+Stress-CTP. In 291 prospectively enrolled patients, cCTA+FFRCT, cCTA+Stress-CTP and cCTA+FFRCT+Stress-CTP showed a similar rate of reclassification of cCTA findings when FFRCT and Stress-CTP were added to cCTA. cCTA, cCTA+FFRCT, cCTA+Stress-CTP and cCTA+FFRCT+Stress-CTP showed a rate of agreement versus the final therapeutic decision of 63%, 71%, 89%, 84% (cCTA+Stress-CTP and cCTA+FFRCT+Stress-CTP vs cCTA and cCTA+FFRCT: p < 0.01), respectively, and a rate of agreement in terms of the vessels to be revascularized of 57%, 64%, 74%, 71% (cCTA+Stress-CTP and cCTA+FFRCT+Stress-CTP vs cCTA and cCTA+FFRCT: p < 0.01), respectively, with an effective radiation dose (ED) of 2.9 ± 1.3 mSv, 2.9 ± 1.3 mSv, 5.9 ± 2.7 mSv, and 3.1 ± 2.1 mSv. The addition of FFRCT and Stress-CTP improved therapeutic decision-making compared to cCTA alone, and a sequential strategy with cCTA+FFRCT+Stress-CTP represents the best compromise in terms of clinical impact and radiation exposure.

Design of CTP-PRO study (impact of stress Cardiac computed Tomography myocardial Perfusion on downstream resources and PROgnosis in patients with suspected or known coronary artery disease: A multicenter international study).

BACKGROUND: CT myocardial perfusion imaging (CTP) represents one of the newly developed CT-based techniques but its cost-effectiveness in the clinical pathway is undefined. The aim of the study is to evaluate the usefulness of combined evaluation of coronary anatomy and myocardial perfusion in intermediate to high-risk patients for suspected CAD or with known disease in terms of clinical decision-making, resource utilization and outcomes in a broad variety of geographic areas and patient subgroups. METHODS: CTP-PRO study is a cooperative, international, multicentre, prospective, open-label, randomized controlled study evaluating the cost-effectiveness of a CCTA+CTP strategy (Group A) versus usual care (Group B) in intermediate-high risk patients with suspected or known CAD who undergo clinically indicated diagnostic evaluation. A total sample size of 2000 subjects will be enrolled and followed up for 24 months. The primary endpoint is the reclassification rate of CCTA in group A due to the addition of CTP. The secondary endpoint will be the comparison between groups in terms of non-invasive and invasive downstream testing, prevalence of obstructive CAD at ICA, revascularization, cumulative ED and overall cost during the follow-up at 1- and 2-years. The tertiary endpoint will be the comparison between each group in terms of MACE and cost-effectiveness at 1- and 2-years. CONCLUSIONS: The study will provide information to patients, health care providers and other stakeholders about which strategy could be more effective in the diagnosis of suspected CAD in intermediate to high-risk patients or in the symptomatic patients with known CAD and previous history of revascularization.

Association Between Haptoglobin Phenotype and Microvascular Obstruction in Patients With STEMI: A Cardiac Magnetic Resonance Study.

OBJECTIVES: This study aimed to evaluate the correlation between different haptoglobin (Hp) phenotypes and myocardial infarction characteristics as detected by cardiac magnetic resonance (CMR) in consecutive patients after ST-segment elevation myocardial infarction (STEMI). BACKGROUND: Hp is a plasma protein that prevents iron-mediated oxidative tissue damage. CMR has emerged as the gold standard technique to detect left ventricular ejection fraction (LVEF), extent of scar with late gadolinium enhancement (LGE) technique, microvascular obstruction (MVO), and myocardial hemorrhage (MH) in patients with STEMI treated by primary percutaneous coronary intervention (pPCI). METHODS: A total of 145 consecutive STEMI patients (mean age 62.2 ± 10.3 years; 78% men) were prospectively enrolled and underwent Hp phenotyping and CMR assessment within 1 week after STEMI. RESULTS: CMR showed an area at risk (AAR) involving 26.6 ± 19.1% of left ventricular (LV) mass with a late LGE extent of 15.2 ± 13.1% of LV mass. MVO and MH occurred in 38 (26%) and 12 (8%) patients, respectively. Hp phenotypes 1-1, 2-1, 2-2 were observed in 15 (10%), 62 (43%), and 68 (47%), respectively. Multivariable analysis demonstrated that body mass index, Hp2-2, diabetes, and peak troponin I were independent predictors of MVO with Hp2-2 associated with the highest odds ratio (OR) (OR: 5.5 [95% confidence interval [CI]: 2.1 to 14.3; p < 0.001]). Hp2-2 significantly predicted both the presence (area under the curve [AUC]: 0.63 [95% CI: 0.53 to 0.72; p = 0.008]) and extent of MVO (AUC: 0.63 [95% CI: 0.54 to 0.72; p = 0.007]). CONCLUSIONS: Hp phenotype is an independent predictor of MVO. Therefore, Hp phenotyping could be used for risk stratification and may be useful in assessing new therapies to reduce myocardial reperfusion injury in patients with STEMI.