Introduction The risk for stroke in adults with congenital heart disease (ACHD) is increased, esp... more Introduction The risk for stroke in adults with congenital heart disease (ACHD) is increased, especially in the setting of commonly ensuing atrial arrhythmias (AA), namely atrial fibrillation, atrial flutter or intra-atrial re-entrant tachycardia. Data are limited regarding treatment with non-vitamin K oral anticoagulants in long-term studies involving patients with ACHD and AA. Methods and analysis PReventiOn of ThromboEmbolism in Adults with Congenital HearΤ disease and Atrial aRrhythmias is a prospective, multicenter, single-arm, non-interventional cohort study designed to investigate the safety and efficacy of apixaban for the prevention of thromboembolism in ACHD with AA in a 'real-world' setting. Eligible patients will be evaluated by the means of available registries and clinical counter. The study aims to accumulate approximately 500 patient-years of exposure to apixaban as part of routine care. Enrolment will take place at four ACHD centres in Greece. The first patient was enrolled in July 2019. The primary efficacy endpoint is a composite of stroke, systemic or pulmonary embolism and intracardiac thrombosis. The primary safety endpoint is major bleeding, according to the International Society on Thrombosis and Haemostasis bleeding criteria. Ethics and dissemination The study protocol has been approved by the institutional review board/ independent ethics committee at each site prior to study commencement. All patients will provide written informed consent. Results will be disseminated at scientific meetings and published in peer-reviewed journals. Trial registration number NCT03854149; Pre-results.
Myocardial infarction with nonobstructive coronary arteries (MINOCA) is a distinct subtype of myo... more Myocardial infarction with nonobstructive coronary arteries (MINOCA) is a distinct subtype of myocardial infarction (MI), occurring in about 8–10% of spontaneous MI cases referred for coronary angiography. Unlike MI with obstructive coronary artery disease, MINOCA’s pathogenesis is more intricate and heterogeneous, involving mechanisms such as coronary thromboembolism, coronary vasospasm, microvascular dysfunction, dissection, or plaque rupture. Diagnosing MINOCA presents challenges and includes invasive and non-invasive strategies aiming to differentiate it from alternative diagnoses and confirm the criteria of elevated cardiac biomarkers, non-obstructive coronary arteries, and the absence of alternate explanations for the acute presentation. Tailored management strategies for MINOCA hinge on identifying the underlying cause of the infarction, necessitating systematic diagnostic approaches. Furthermore, determining the optimal post-MINOCA medication regimen remains uncertain. This ...
Journal of the American College of Cardiology, Mar 1, 2020
Background: While myocardial flow reserve (MFR) may identify patients with coronary artery diseas... more Background: While myocardial flow reserve (MFR) may identify patients with coronary artery disease who benefit from early revascularization, it is unknown whether MFR may guide patient management in ischemic heart failure as well. Methods: This retrospective study included 263 patients with ischemic heart failure referred for stress/rest myocardial perfusion imaging and viability testing using positron emission tomography (PET). The endpoint was any major adverse cardiac event (MACE) consisting of all-cause death, resuscitated sudden cardiac death, heart transplantation, acute coronary syndrome, hospitalization for heart failure, and late revascularization (>90 days). Patients were stratified by treatment strategy (i.e., no early revascularization, early percutaneous coronary intervention [PCI], early coronary artery bypass grafting [CABG]) and by presence of low MFR (i.e. <1.2) or significant myocardium at risk (i.e., ischemia and/or viability ≥10%). Results: Of the 53 patients (20%) that were revascularized within 90 days, 27 patients (10%) underwent early PCI and 26 patients (10%) early CABG. MACE occurred in 174 patients (66%) during median follow-up of 3.3 years. Among patients with low MFR, those with early CABG had lower annualized MACE rates compared to those with early PCI (8% vs. 40%, p=0.035) or those without early revascularization (8% vs. 33%, p=0.018). In contrast, patients with early PCI had similar annualized MACE rates compared to those without early revascularization (40% vs. 33%, p=0.615). Among patients with high MFR, on the contrary, early CABG was not associated with a lower annualized MACE rate compared to early PCI (11% vs. 17%, p=0.359) or no early revascularization (11% vs. 17%, p=0.283). In addition, annualized MACE rate did not differ between patients with early PCI and those without early revascularization (17% vs. 17%, p=0.986). The presence of significant myocardium at risk did not modify the response to the treatment strategy (all comparisons, p>0.05). Conclusion: In patients with ischemic heart failure, PET-derived MFR may identify patients with an outcome benefit from early CABG but not PCI.
The purpose of this study was to quantify the reduction in radiation dose achievable by using the... more The purpose of this study was to quantify the reduction in radiation dose achievable by using the optimal z-axis coverage in coronary computed tomography (CT) angiography (CCTA) on a latest-generation 256-slice scanner. Methods: A total of 408 scans were reviewed that were performed on a wide-range detector scanner allowing up to 16-cm z-axis coverage (adjustable in 2-cm increments). For each CCTA study, we assessed the radiation dose (ie, dose-length product and volume CT dose index) and measured the minimum z-axis coverage necessary to cover the complete cardiac anatomy. We calculated the potential radiation dose savings achievable through reduction of the z-axis coverage to the minimum necessary. Results: The majority of the CCTA scans were performed with a z-axis coverage of 16 cm (n = 285, 69.9%), followed by 14 cm (n = 121, 29.7%) and 12 cm (n = 2, 0.5%). In the group that was scanned with a collimation of 16 cm, radiation dose could have been reduced by 12.5% in 55 patients, 25% in 195 patients, and 37.5% in 33 patients when using optimal z-axis coverage for CCTA. In the group that was scanned with a collimation of 14 cm, radiation dose could have been reduced by 14.3% in 90 patients, and 28.6% in 30 patients, whereas in the group that was scanned with a collimation of 12 cm, dose could have been reduced by 16.7% in 2 patients. Conclusions: Using correct z-axis coverage in CCTA on a latestgeneration 256-slice scanner yields average dose reductions of 22.0% but may be as high as 37.5%.
Funding Acknowledgements Type of funding sources: Public grant(s) – EU funding. Main funding sour... more Funding Acknowledgements Type of funding sources: Public grant(s) – EU funding. Main funding source(s): This research is co-financed by Greece and the European Union (European Social Fund-ESF) through the Operational Programme «Human Resources Development, Education and Lifelong Learning 2014-2020» in the context of the project “Correlation of coronary artery tree geometry and clinical parameters with the distribution, complexity and severity of coronary artery disease: a pilot study using multislice CT coronary angiography” (MIS 5047882) Background Development and progression of coronary atherosclerosis is complex and not yet fully understood. Accumulative evidence supports the notion that coronary artery disease (CAD) results from an interaction of systemic factors, such as dyslipidemia, with local hemodynamic factors that regulate the site-specific predilection of atherosclerosis, particularly low endothelial shear stress (ESS). Since low ESS develops in geometrically irregular r...
European Journal of Nuclear Medicine and Molecular Imaging, 2020
Aims Perivascular fat attenuation index (FAI) has emerged as a novel coronary computed tomography... more Aims Perivascular fat attenuation index (FAI) has emerged as a novel coronary computed tomography angiography (CCTA)–based biomarker predicting cardiovascular outcomes by capturing early coronary inflammation. It is currently unknown whether FAI adds prognostic value beyond that provided by single-photon emission computed tomography myocardial perfusion imaging (SPECT-MPI) and CCTA findings including coronary artery calcium scoring (CACS). Methods and results A total of 492 patients (mean age 62.5 ± 10.8 years) underwent clinically indicated multimodality CCTA and electrocardiography (ECG)-gated 99mTc-tetrofosmin SPECT-MPI between May 2005 and December 2008 at our institution, and follow-up data on major adverse cardiovascular events (MACE) was obtained for 314 patients. FAI was obtained from CCTA images and was measured around the right coronary artery (FAI[RCA]), the left anterior descending artery (FAI[LAD]), and the left main coronary artery (FAI[LMCA]). During a median follow-u...
The aim of this study was to investigate the prognostic and clinical value of quantitative positr... more The aim of this study was to investigate the prognostic and clinical value of quantitative positron emission tomographic (PET) metrics in patients with ischemic heart failure. BACKGROUND Although myocardial flow reserve (MFR) is a strong predictor of cardiac risk in patients without heart failure, it is unknown whether quantitative PET metrics improve risk stratification in patients with ischemic heart failure. METHODS The study included 254 patients referred for stress and rest myocardial perfusion imaging and viability testing using PET. Major adverse cardiac event(s) (MACE) consisted of death, resuscitated sudden cardiac death, heart transplantation, acute coronary syndrome, hospitalization for heart failure, and late revascularization. RESULTS MACE occurred in 170 patients (67%) during a median follow-up of 3.3 years. In a multivariate Cox proportional hazards model including multiple quantitative PET metrics, only MFR predicted MACE significantly (p ¼ 0.013). Beyond age, symptom severity, diabetes mellitus, previous myocardial infarction or revascularization, 3-vessel disease, renal insufficiency, ejection fraction, as well as presence and burden of ischemia, scar, and hibernating myocardium, MFR was strongly associated with MACE (adjusted hazard ratio per increase in MFR by 1: 0.63; 95% confidence interval: 0.45 to 0.91). Incorporation of MFR into a risk assessment model incrementally improved the prediction of MACE (likelihood ratio chi-square test [16] ¼ 48.61 vs. chi-square test [15] ¼ 39.20; p ¼ 0.002). CONCLUSIONS In this retrospective analysis of a single-center cohort, quantitative PET metrics of myocardial blood flow all improved risk stratification in patients with ischemic heart failure. However, in a hypothesis-generating analysis, MFR appears modestly superior to the other metrics as a prognostic index.
Background Valvular heart disease (VHD) in non-valvular atrial fibrillation (AF) is a puzzling cl... more Background Valvular heart disease (VHD) in non-valvular atrial fibrillation (AF) is a puzzling clinical entity. The aim of this study was to evaluate the prognostic effect of significant VHD (sVHD) among patients with non-valvular AF. Methods This is a post-hoc analysis of the MISOAC-AF trial (NCT02941978). Consecutive inpatients with non-valvular AF who underwent echocardiography were included. sVHD was defined as the presence of at least moderate aortic stenosis (AS) or aortic/mitral/tricuspid regurgitation (AR/MR/TR). Cox regression analyses with covariate adjustments were used for outcome prediction. Results In total, 983 patients with non-valvular AF (median age 76 [14] years) were analyzed over a median follow-up period of 32 [20] months. sVHD was diagnosed in 575 (58.5%) AF patients. sVHD was associated with all-cause mortality (21.6%/yr vs. 6.5%/yr; adjusted HR [aHR] 1.55, 95% confidence interval [CI] 1.17–2.06; p = 0.02), cardiovascular mortality (16%/yr vs. 4%/yr; aHR 1.70...
BACKGROUND This study sought to develop and validate a risk score for predicting mortality in pat... more BACKGROUND This study sought to develop and validate a risk score for predicting mortality in patients with AF after a hospitalization for cardiac reasons. METHODS The new risk score was derived by a prospective cohort of hospitalized patients with concurrent AF. The outcome measures were all-cause and cardiovascular mortality. Random forest was used for variable selection. A risk points model with predictor variables was developed by weighted Cox-regression coefficients and was internally validated by bootstrapping. RESULTS In total, 1130 patients with AF were included. During a median follow-up of 2 years, 346 (30.6%) patients died, 250 of whom had a cardiovascular cause of death. N-terminal pro-B-type natriuretic peptide and high-sensitivity troponin-T were the most important predictors of mortality, followed by indexed left atrial volume, history and type of heart failure, age, history of diabetes mellitus, and intraventricular conduction delay, all forming the BASIC-AF risk score (Biomarkers, Age, ultraSound, Intraventricular conduction delay, Clinical history). The score had good discrimination for all-cause (c-index=0.85, 95% CI 0.82-0.88) and cardiovascular death (c-index=0.84, 95% CI 0.81-0.87). The predicted probability of mortality varied more than 50-fold across deciles and adjusted well to observed mortality rates. Decision curve analysis revealed a significant net benefit of using the BASIC-AF risk score to predict the risk of death, compared with other existing risk schemes. CONCLUSIONS We developed and internally validated a well-performing novel risk score for predicting death in patients with AF. The BASIC-AF risk score included routinely assessed parameters, selected through machine learning algorithms, and may assist in tailored risk stratification and management of these patients.
Journal of Cardiovascular Computed Tomography, 2020
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Background Coronary computed tomography angiography (CCTA) provides incremental prognostic inform... more Background Coronary computed tomography angiography (CCTA) provides incremental prognostic information over traditional risk factors in patients with suspected coronary artery disease. However, little is known about the long-term predictive performance of CCTA-derived coronary volumes and mid-diastolic left ventricular (LV) mass. Purpose To assess long-term prognostic value of coronary volumes and mid-diastolic LV mass as novel potential imaging predictors derived from low-dose prospectively ECG-triggered CCTA. Methods Consecutive patients with suspected or known coronary artery disease, referred for low-dose CCTA, were included. Patients with previous revascularization were excluded. The following parameters were evaluated: calcium score, segment involvement score (SIS: 1 point for each coronary segment with presence of plaque), coronary volume, mid-diastolic LV mass and coronary volume indexed to LV mass. Major adverse cardiovascular events (MACE) were defined as all-cause death, ...
Aims Myocardial infarction with non-obstructive coronary arteries (MINOCA) is a clinical entity w... more Aims Myocardial infarction with non-obstructive coronary arteries (MINOCA) is a clinical entity with several causes and pathophysiologic mechanisms. Secondary prevention with medical therapy used in patients with obstructive coronary artery disease has unclear benefits in MINOCA patients. Methods and Results Literature search was conducted until 08 March 2022. Random-effects frequentist and hierarchical Bayesian meta-analyses were performed to assess the clinical impact of medical therapy (RAAS inhibitors, statins, DAPT, β-blockers) in MINOCA patients. Outcomes of interest were all-cause mortality and major adverse cardiovascular events (MACE). A total of 12,663 MINOCA patients among 5 observational studies were analyzed. Mean follow-up ranged from 12 to 90 months across studies. In frequentist meta-analysis, statins and β-blockers were associated with lower risk of all-cause mortality [pooled adjusted hazard ratios (aHR) 0.53 and 0.81, with 95% confidence intervals (CI) (0.37-0.76)...
The prognostic value of health status metrics in patients with adult congenital heart disease (AC... more The prognostic value of health status metrics in patients with adult congenital heart disease (ACHD) and atrial arrhythmias is unclear. In this retrospective cohort study of an ongoing national, multicenter registry (PROTECT-AR, NCT03854149), ACHD patients with atrial arrhythmias on apixaban are included. At baseline, health metrics were assessed using the physical component summary (PCS), the mental component summary (MCS) of the Short-Form-36 (SF-36) Health Survey, and the modified European Heart Rhythm Association (mEHRA) score. Patients were divided into groups according to their SF-36 PCS and MCS scores, using the normalized population mean of 50 on the PCS and MCS as a threshold. The primary outcome was the composite of mortality from any cause, major thromboembolic events, major/clinically relevant non-major bleedings, or hospitalizations. Multivariable Cox-regression analyses using clinically relevant parameters (age greater than 60 years, anatomic complexity, ejection fract...
Coronary artery disease (CAD) represents a modern pandemic associated with significant morbidity ... more Coronary artery disease (CAD) represents a modern pandemic associated with significant morbidity and mortality. The multi-faceted pathogenesis of this entity has long been investigated, highlighting the contribution of systemic factors such as hyperlipidemia and hypertension. Nevertheless, recent research has drawn light to the importance of geometrical features of coronary vasculature on the complexity and vulnerability of coronary atherosclerosis. Various parameters have been investigated so far, including vessel-length, cross-sectional area, curvature, and tortuosity, using primarily invasive angiography and recently non-invasive cardiac computed tomography angiography (CCTA). It is clear that there is correlation between geometrical parameters and both the haemodynamic alterations augmenting the atherosclerosis-prone environment and the extent of plaque burden. The purpose of this review is to discuss the currently available literature regarding this issue and propose a potentia...
The implications of the adult congenital heart disease anatomic and physiological classification ... more The implications of the adult congenital heart disease anatomic and physiological classification (AP-ACHD) for risk assessment have not been adequately studied. A retrospective cohort study was conducted using data from an ongoing national, multicentre registry of patients with ACHD and atrial arrhythmias (AA) receiving apixaban (PROTECT-AR study, NCT03854149). At enrollment, patients were stratified according to Anatomic class (AnatC, range I to III) and physiological stage (PhyS, range B to D). Follow-up was conducted between May 2019 and September 2021. The primary outcome was a composite of death from any cause, any major thromboembolic event, major or clinically relevant non-major bleeding, or hospitalization. Cox proportional-hazards regression modeling was used to evaluate the risks for the outcome among AP-ACHD classes. Over a median 20-month follow-up period, 47 of 157 (29.9%) ACHD patients with AA experienced the composite outcome. Adjusted hazard ratios (aHR) with 95% con...
Cardiac computed tomography (CCT) is now considered a first-line diagnostic test for suspected co... more Cardiac computed tomography (CCT) is now considered a first-line diagnostic test for suspected coronary artery disease (CAD) providing a non-invasive, qualitative, and quantitative assessment of the coronary arteries and pericoronary regions. CCT assesses vascular calcification and coronary lumen narrowing, measures total plaque burden, identifies plaque composition and high-risk plaque features and can even assist with hemodynamic evaluation of coronary lesions. Recent research focuses on computing coronary endothelial shear stress, a potent modulator in the development and progression of atherosclerosis, as well as differentiating an inflammatory from a non-inflammatory pericoronary artery environment using the simple measurement of pericoronary fat attenuation index. In the present review, we discuss the role of the above in the diagnosis of coronary atherosclerosis and the prediction of adverse cardiovascular events. Additionally, we review the current limitations of cardiac com...
IntroductionMyocardial infarction with non-obstructive coronary arteries (MINOCA) occurs in 5%–15... more IntroductionMyocardial infarction with non-obstructive coronary arteries (MINOCA) occurs in 5%–15% of all patients with acute myocardial infarction. Cardiac MR (CMR) and optical coherence tomography have been used to identify the underlying pathophysiological mechanism in MINOCA. The role of cardiac CT angiography (CCTA) in patients with MINOCA, however, has not been well studied so far. CCTA can be used to assess atherosclerotic plaque volume, vulnerable plaque characteristics as well as pericoronary fat tissue attenuation, which has not been yet studied in MINOCA.Methods and analysisMINOCA-GR is a prospective, multicentre, observational cohort study based on a national registry that will use CCTA in combination with CMR and invasive coronary angiography (ICA) to evaluate the extent and characteristics of coronary atherosclerosis and its correlation with pericoronary fat attenuation in patients with MINOCA. A total of 60 consecutive adult patients across 4 participating study sites...
Introduction The risk for stroke in adults with congenital heart disease (ACHD) is increased, esp... more Introduction The risk for stroke in adults with congenital heart disease (ACHD) is increased, especially in the setting of commonly ensuing atrial arrhythmias (AA), namely atrial fibrillation, atrial flutter or intra-atrial re-entrant tachycardia. Data are limited regarding treatment with non-vitamin K oral anticoagulants in long-term studies involving patients with ACHD and AA. Methods and analysis PReventiOn of ThromboEmbolism in Adults with Congenital HearΤ disease and Atrial aRrhythmias is a prospective, multicenter, single-arm, non-interventional cohort study designed to investigate the safety and efficacy of apixaban for the prevention of thromboembolism in ACHD with AA in a 'real-world' setting. Eligible patients will be evaluated by the means of available registries and clinical counter. The study aims to accumulate approximately 500 patient-years of exposure to apixaban as part of routine care. Enrolment will take place at four ACHD centres in Greece. The first patient was enrolled in July 2019. The primary efficacy endpoint is a composite of stroke, systemic or pulmonary embolism and intracardiac thrombosis. The primary safety endpoint is major bleeding, according to the International Society on Thrombosis and Haemostasis bleeding criteria. Ethics and dissemination The study protocol has been approved by the institutional review board/ independent ethics committee at each site prior to study commencement. All patients will provide written informed consent. Results will be disseminated at scientific meetings and published in peer-reviewed journals. Trial registration number NCT03854149; Pre-results.
Myocardial infarction with nonobstructive coronary arteries (MINOCA) is a distinct subtype of myo... more Myocardial infarction with nonobstructive coronary arteries (MINOCA) is a distinct subtype of myocardial infarction (MI), occurring in about 8–10% of spontaneous MI cases referred for coronary angiography. Unlike MI with obstructive coronary artery disease, MINOCA’s pathogenesis is more intricate and heterogeneous, involving mechanisms such as coronary thromboembolism, coronary vasospasm, microvascular dysfunction, dissection, or plaque rupture. Diagnosing MINOCA presents challenges and includes invasive and non-invasive strategies aiming to differentiate it from alternative diagnoses and confirm the criteria of elevated cardiac biomarkers, non-obstructive coronary arteries, and the absence of alternate explanations for the acute presentation. Tailored management strategies for MINOCA hinge on identifying the underlying cause of the infarction, necessitating systematic diagnostic approaches. Furthermore, determining the optimal post-MINOCA medication regimen remains uncertain. This ...
Journal of the American College of Cardiology, Mar 1, 2020
Background: While myocardial flow reserve (MFR) may identify patients with coronary artery diseas... more Background: While myocardial flow reserve (MFR) may identify patients with coronary artery disease who benefit from early revascularization, it is unknown whether MFR may guide patient management in ischemic heart failure as well. Methods: This retrospective study included 263 patients with ischemic heart failure referred for stress/rest myocardial perfusion imaging and viability testing using positron emission tomography (PET). The endpoint was any major adverse cardiac event (MACE) consisting of all-cause death, resuscitated sudden cardiac death, heart transplantation, acute coronary syndrome, hospitalization for heart failure, and late revascularization (>90 days). Patients were stratified by treatment strategy (i.e., no early revascularization, early percutaneous coronary intervention [PCI], early coronary artery bypass grafting [CABG]) and by presence of low MFR (i.e. <1.2) or significant myocardium at risk (i.e., ischemia and/or viability ≥10%). Results: Of the 53 patients (20%) that were revascularized within 90 days, 27 patients (10%) underwent early PCI and 26 patients (10%) early CABG. MACE occurred in 174 patients (66%) during median follow-up of 3.3 years. Among patients with low MFR, those with early CABG had lower annualized MACE rates compared to those with early PCI (8% vs. 40%, p=0.035) or those without early revascularization (8% vs. 33%, p=0.018). In contrast, patients with early PCI had similar annualized MACE rates compared to those without early revascularization (40% vs. 33%, p=0.615). Among patients with high MFR, on the contrary, early CABG was not associated with a lower annualized MACE rate compared to early PCI (11% vs. 17%, p=0.359) or no early revascularization (11% vs. 17%, p=0.283). In addition, annualized MACE rate did not differ between patients with early PCI and those without early revascularization (17% vs. 17%, p=0.986). The presence of significant myocardium at risk did not modify the response to the treatment strategy (all comparisons, p>0.05). Conclusion: In patients with ischemic heart failure, PET-derived MFR may identify patients with an outcome benefit from early CABG but not PCI.
The purpose of this study was to quantify the reduction in radiation dose achievable by using the... more The purpose of this study was to quantify the reduction in radiation dose achievable by using the optimal z-axis coverage in coronary computed tomography (CT) angiography (CCTA) on a latest-generation 256-slice scanner. Methods: A total of 408 scans were reviewed that were performed on a wide-range detector scanner allowing up to 16-cm z-axis coverage (adjustable in 2-cm increments). For each CCTA study, we assessed the radiation dose (ie, dose-length product and volume CT dose index) and measured the minimum z-axis coverage necessary to cover the complete cardiac anatomy. We calculated the potential radiation dose savings achievable through reduction of the z-axis coverage to the minimum necessary. Results: The majority of the CCTA scans were performed with a z-axis coverage of 16 cm (n = 285, 69.9%), followed by 14 cm (n = 121, 29.7%) and 12 cm (n = 2, 0.5%). In the group that was scanned with a collimation of 16 cm, radiation dose could have been reduced by 12.5% in 55 patients, 25% in 195 patients, and 37.5% in 33 patients when using optimal z-axis coverage for CCTA. In the group that was scanned with a collimation of 14 cm, radiation dose could have been reduced by 14.3% in 90 patients, and 28.6% in 30 patients, whereas in the group that was scanned with a collimation of 12 cm, dose could have been reduced by 16.7% in 2 patients. Conclusions: Using correct z-axis coverage in CCTA on a latestgeneration 256-slice scanner yields average dose reductions of 22.0% but may be as high as 37.5%.
Funding Acknowledgements Type of funding sources: Public grant(s) – EU funding. Main funding sour... more Funding Acknowledgements Type of funding sources: Public grant(s) – EU funding. Main funding source(s): This research is co-financed by Greece and the European Union (European Social Fund-ESF) through the Operational Programme «Human Resources Development, Education and Lifelong Learning 2014-2020» in the context of the project “Correlation of coronary artery tree geometry and clinical parameters with the distribution, complexity and severity of coronary artery disease: a pilot study using multislice CT coronary angiography” (MIS 5047882) Background Development and progression of coronary atherosclerosis is complex and not yet fully understood. Accumulative evidence supports the notion that coronary artery disease (CAD) results from an interaction of systemic factors, such as dyslipidemia, with local hemodynamic factors that regulate the site-specific predilection of atherosclerosis, particularly low endothelial shear stress (ESS). Since low ESS develops in geometrically irregular r...
European Journal of Nuclear Medicine and Molecular Imaging, 2020
Aims Perivascular fat attenuation index (FAI) has emerged as a novel coronary computed tomography... more Aims Perivascular fat attenuation index (FAI) has emerged as a novel coronary computed tomography angiography (CCTA)–based biomarker predicting cardiovascular outcomes by capturing early coronary inflammation. It is currently unknown whether FAI adds prognostic value beyond that provided by single-photon emission computed tomography myocardial perfusion imaging (SPECT-MPI) and CCTA findings including coronary artery calcium scoring (CACS). Methods and results A total of 492 patients (mean age 62.5 ± 10.8 years) underwent clinically indicated multimodality CCTA and electrocardiography (ECG)-gated 99mTc-tetrofosmin SPECT-MPI between May 2005 and December 2008 at our institution, and follow-up data on major adverse cardiovascular events (MACE) was obtained for 314 patients. FAI was obtained from CCTA images and was measured around the right coronary artery (FAI[RCA]), the left anterior descending artery (FAI[LAD]), and the left main coronary artery (FAI[LMCA]). During a median follow-u...
The aim of this study was to investigate the prognostic and clinical value of quantitative positr... more The aim of this study was to investigate the prognostic and clinical value of quantitative positron emission tomographic (PET) metrics in patients with ischemic heart failure. BACKGROUND Although myocardial flow reserve (MFR) is a strong predictor of cardiac risk in patients without heart failure, it is unknown whether quantitative PET metrics improve risk stratification in patients with ischemic heart failure. METHODS The study included 254 patients referred for stress and rest myocardial perfusion imaging and viability testing using PET. Major adverse cardiac event(s) (MACE) consisted of death, resuscitated sudden cardiac death, heart transplantation, acute coronary syndrome, hospitalization for heart failure, and late revascularization. RESULTS MACE occurred in 170 patients (67%) during a median follow-up of 3.3 years. In a multivariate Cox proportional hazards model including multiple quantitative PET metrics, only MFR predicted MACE significantly (p ¼ 0.013). Beyond age, symptom severity, diabetes mellitus, previous myocardial infarction or revascularization, 3-vessel disease, renal insufficiency, ejection fraction, as well as presence and burden of ischemia, scar, and hibernating myocardium, MFR was strongly associated with MACE (adjusted hazard ratio per increase in MFR by 1: 0.63; 95% confidence interval: 0.45 to 0.91). Incorporation of MFR into a risk assessment model incrementally improved the prediction of MACE (likelihood ratio chi-square test [16] ¼ 48.61 vs. chi-square test [15] ¼ 39.20; p ¼ 0.002). CONCLUSIONS In this retrospective analysis of a single-center cohort, quantitative PET metrics of myocardial blood flow all improved risk stratification in patients with ischemic heart failure. However, in a hypothesis-generating analysis, MFR appears modestly superior to the other metrics as a prognostic index.
Background Valvular heart disease (VHD) in non-valvular atrial fibrillation (AF) is a puzzling cl... more Background Valvular heart disease (VHD) in non-valvular atrial fibrillation (AF) is a puzzling clinical entity. The aim of this study was to evaluate the prognostic effect of significant VHD (sVHD) among patients with non-valvular AF. Methods This is a post-hoc analysis of the MISOAC-AF trial (NCT02941978). Consecutive inpatients with non-valvular AF who underwent echocardiography were included. sVHD was defined as the presence of at least moderate aortic stenosis (AS) or aortic/mitral/tricuspid regurgitation (AR/MR/TR). Cox regression analyses with covariate adjustments were used for outcome prediction. Results In total, 983 patients with non-valvular AF (median age 76 [14] years) were analyzed over a median follow-up period of 32 [20] months. sVHD was diagnosed in 575 (58.5%) AF patients. sVHD was associated with all-cause mortality (21.6%/yr vs. 6.5%/yr; adjusted HR [aHR] 1.55, 95% confidence interval [CI] 1.17–2.06; p = 0.02), cardiovascular mortality (16%/yr vs. 4%/yr; aHR 1.70...
BACKGROUND This study sought to develop and validate a risk score for predicting mortality in pat... more BACKGROUND This study sought to develop and validate a risk score for predicting mortality in patients with AF after a hospitalization for cardiac reasons. METHODS The new risk score was derived by a prospective cohort of hospitalized patients with concurrent AF. The outcome measures were all-cause and cardiovascular mortality. Random forest was used for variable selection. A risk points model with predictor variables was developed by weighted Cox-regression coefficients and was internally validated by bootstrapping. RESULTS In total, 1130 patients with AF were included. During a median follow-up of 2 years, 346 (30.6%) patients died, 250 of whom had a cardiovascular cause of death. N-terminal pro-B-type natriuretic peptide and high-sensitivity troponin-T were the most important predictors of mortality, followed by indexed left atrial volume, history and type of heart failure, age, history of diabetes mellitus, and intraventricular conduction delay, all forming the BASIC-AF risk score (Biomarkers, Age, ultraSound, Intraventricular conduction delay, Clinical history). The score had good discrimination for all-cause (c-index=0.85, 95% CI 0.82-0.88) and cardiovascular death (c-index=0.84, 95% CI 0.81-0.87). The predicted probability of mortality varied more than 50-fold across deciles and adjusted well to observed mortality rates. Decision curve analysis revealed a significant net benefit of using the BASIC-AF risk score to predict the risk of death, compared with other existing risk schemes. CONCLUSIONS We developed and internally validated a well-performing novel risk score for predicting death in patients with AF. The BASIC-AF risk score included routinely assessed parameters, selected through machine learning algorithms, and may assist in tailored risk stratification and management of these patients.
Journal of Cardiovascular Computed Tomography, 2020
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Background Coronary computed tomography angiography (CCTA) provides incremental prognostic inform... more Background Coronary computed tomography angiography (CCTA) provides incremental prognostic information over traditional risk factors in patients with suspected coronary artery disease. However, little is known about the long-term predictive performance of CCTA-derived coronary volumes and mid-diastolic left ventricular (LV) mass. Purpose To assess long-term prognostic value of coronary volumes and mid-diastolic LV mass as novel potential imaging predictors derived from low-dose prospectively ECG-triggered CCTA. Methods Consecutive patients with suspected or known coronary artery disease, referred for low-dose CCTA, were included. Patients with previous revascularization were excluded. The following parameters were evaluated: calcium score, segment involvement score (SIS: 1 point for each coronary segment with presence of plaque), coronary volume, mid-diastolic LV mass and coronary volume indexed to LV mass. Major adverse cardiovascular events (MACE) were defined as all-cause death, ...
Aims Myocardial infarction with non-obstructive coronary arteries (MINOCA) is a clinical entity w... more Aims Myocardial infarction with non-obstructive coronary arteries (MINOCA) is a clinical entity with several causes and pathophysiologic mechanisms. Secondary prevention with medical therapy used in patients with obstructive coronary artery disease has unclear benefits in MINOCA patients. Methods and Results Literature search was conducted until 08 March 2022. Random-effects frequentist and hierarchical Bayesian meta-analyses were performed to assess the clinical impact of medical therapy (RAAS inhibitors, statins, DAPT, β-blockers) in MINOCA patients. Outcomes of interest were all-cause mortality and major adverse cardiovascular events (MACE). A total of 12,663 MINOCA patients among 5 observational studies were analyzed. Mean follow-up ranged from 12 to 90 months across studies. In frequentist meta-analysis, statins and β-blockers were associated with lower risk of all-cause mortality [pooled adjusted hazard ratios (aHR) 0.53 and 0.81, with 95% confidence intervals (CI) (0.37-0.76)...
The prognostic value of health status metrics in patients with adult congenital heart disease (AC... more The prognostic value of health status metrics in patients with adult congenital heart disease (ACHD) and atrial arrhythmias is unclear. In this retrospective cohort study of an ongoing national, multicenter registry (PROTECT-AR, NCT03854149), ACHD patients with atrial arrhythmias on apixaban are included. At baseline, health metrics were assessed using the physical component summary (PCS), the mental component summary (MCS) of the Short-Form-36 (SF-36) Health Survey, and the modified European Heart Rhythm Association (mEHRA) score. Patients were divided into groups according to their SF-36 PCS and MCS scores, using the normalized population mean of 50 on the PCS and MCS as a threshold. The primary outcome was the composite of mortality from any cause, major thromboembolic events, major/clinically relevant non-major bleedings, or hospitalizations. Multivariable Cox-regression analyses using clinically relevant parameters (age greater than 60 years, anatomic complexity, ejection fract...
Coronary artery disease (CAD) represents a modern pandemic associated with significant morbidity ... more Coronary artery disease (CAD) represents a modern pandemic associated with significant morbidity and mortality. The multi-faceted pathogenesis of this entity has long been investigated, highlighting the contribution of systemic factors such as hyperlipidemia and hypertension. Nevertheless, recent research has drawn light to the importance of geometrical features of coronary vasculature on the complexity and vulnerability of coronary atherosclerosis. Various parameters have been investigated so far, including vessel-length, cross-sectional area, curvature, and tortuosity, using primarily invasive angiography and recently non-invasive cardiac computed tomography angiography (CCTA). It is clear that there is correlation between geometrical parameters and both the haemodynamic alterations augmenting the atherosclerosis-prone environment and the extent of plaque burden. The purpose of this review is to discuss the currently available literature regarding this issue and propose a potentia...
The implications of the adult congenital heart disease anatomic and physiological classification ... more The implications of the adult congenital heart disease anatomic and physiological classification (AP-ACHD) for risk assessment have not been adequately studied. A retrospective cohort study was conducted using data from an ongoing national, multicentre registry of patients with ACHD and atrial arrhythmias (AA) receiving apixaban (PROTECT-AR study, NCT03854149). At enrollment, patients were stratified according to Anatomic class (AnatC, range I to III) and physiological stage (PhyS, range B to D). Follow-up was conducted between May 2019 and September 2021. The primary outcome was a composite of death from any cause, any major thromboembolic event, major or clinically relevant non-major bleeding, or hospitalization. Cox proportional-hazards regression modeling was used to evaluate the risks for the outcome among AP-ACHD classes. Over a median 20-month follow-up period, 47 of 157 (29.9%) ACHD patients with AA experienced the composite outcome. Adjusted hazard ratios (aHR) with 95% con...
Cardiac computed tomography (CCT) is now considered a first-line diagnostic test for suspected co... more Cardiac computed tomography (CCT) is now considered a first-line diagnostic test for suspected coronary artery disease (CAD) providing a non-invasive, qualitative, and quantitative assessment of the coronary arteries and pericoronary regions. CCT assesses vascular calcification and coronary lumen narrowing, measures total plaque burden, identifies plaque composition and high-risk plaque features and can even assist with hemodynamic evaluation of coronary lesions. Recent research focuses on computing coronary endothelial shear stress, a potent modulator in the development and progression of atherosclerosis, as well as differentiating an inflammatory from a non-inflammatory pericoronary artery environment using the simple measurement of pericoronary fat attenuation index. In the present review, we discuss the role of the above in the diagnosis of coronary atherosclerosis and the prediction of adverse cardiovascular events. Additionally, we review the current limitations of cardiac com...
IntroductionMyocardial infarction with non-obstructive coronary arteries (MINOCA) occurs in 5%–15... more IntroductionMyocardial infarction with non-obstructive coronary arteries (MINOCA) occurs in 5%–15% of all patients with acute myocardial infarction. Cardiac MR (CMR) and optical coherence tomography have been used to identify the underlying pathophysiological mechanism in MINOCA. The role of cardiac CT angiography (CCTA) in patients with MINOCA, however, has not been well studied so far. CCTA can be used to assess atherosclerotic plaque volume, vulnerable plaque characteristics as well as pericoronary fat tissue attenuation, which has not been yet studied in MINOCA.Methods and analysisMINOCA-GR is a prospective, multicentre, observational cohort study based on a national registry that will use CCTA in combination with CMR and invasive coronary angiography (ICA) to evaluate the extent and characteristics of coronary atherosclerosis and its correlation with pericoronary fat attenuation in patients with MINOCA. A total of 60 consecutive adult patients across 4 participating study sites...
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Papers by Georgios P . Rampidis