31 research outputs found
PET myocardial perfusion imaging: Trends, challenges, and opportunities
No full textVarious non-invasive images are used in clinical practice for the diagnosis and prognostication of chronic coronary syndromes. Notably, quantitative myocardial perfusion imaging (MPI) through positron emission tomography (PET) has seen significant technical advancements and a substantial increase in its use over the past two decades. This progress has generated an unprecedented wealth of clinical information, which, when properly applied, can diagnose and fine-tune the management of patients with different types of ischemic syndromes. This state-of-art review focuses on quantitative PET MPI, its integration into clinical practice, and how it holds up at the eyes of modern cardiac imaging and revascularization clinical trials, along with future perspectives
Microvascular resistance reserve before and after PCI: A serial FFR and [15O] H2O PET study
No full textBackground and aims: Microvascular Resistance Reserve (MRR) has recently been introduced as a microvasculature-specific index and hypothesized to be independent of coronary stenosis. The aim of this study was to investigate the change of MRR after percutaneous coronary intervention (PCI). Methods: In this post-hoc analysis from the PACIFC trials, symptomatic patients underwent [15O]H2O positron emission tomography (PET) and invasive fractional flow reserve (FFR) before and after revascularization. Coronary flow reserve (CFR) from PET and invasive FFR were used to calculate MRR. Results: Among 52 patients (87 % male, age 59.4 ± 9.4 years), 61 vessels with a median FFR of 0.71 (95 % confidence interval: 0.55 to 0.74) and a mean MRR of 3.80 ± 1.23 were included. Following PCI, FFR, hyperemic myocardial blood flow (hMBF) and CFR increased significantly (all p-values ≤0.001). MRR remained unchanged after PCI (3.80 ± 1.23 before PCI versus 3.60 ± 0.97 after PCI; p=0.23). In vessels with a pre-PCI, FFR ≤0.70 pre- and post-PCI MRR were 3.90 ± 1.30 and 3.73 ± 1.14 (p=0.56), respectively. Similar findings were observed for vessels with a FFR between 0.71 and 0.80 (pre-PCI MRR 3.70 ± 1.17 vs. post PCI MRR 3.48 ± 0.76, p=0.19). Conclusions: Our study indicates that MRR, assessed using a hybrid approach of PET and invasive FFR, is independent of the severity of epicardial stenosis. These findings suggest that MRR is a microvasculature-specific parameter
Derivation and validation of an artificial intelligence-based plaque burden safety cut-off for long-term acute coronary syndrome from coronary computed tomography angiography
No full textAimsArtificial intelligence (AI) has enabled accurate and fast plaque quantification from coronary computed tomography angiography (CCTA). However, AI detects any coronary plaque in up to 97% of patients. To avoid overdiagnosis, a plaque burden safety cut-off for future coronary events is needed.Methods and resultsPercent atheroma volume (PAV) was quantified with AI-guided quantitative computed tomography in a blinded fashion. Safety cut-off derivation was performed in the Turku CCTA registry (Finland), and pre-defined as ≥90% sensitivity for acute coronary syndrome (ACS). External validation was performed in the Amsterdam CCTA registry (the Netherlands). In the derivation cohort, 100/2271 (4.4%) patients experienced ACS (median follow-up 6.9 years). A threshold of PAV ≥ 2.6% was derived with 90.0% sensitivity and negative predictive value (NPV) of 99.0%. In the validation cohort 27/568 (4.8%) experienced ACS (median follow-up 6.7 years) with PAV ≥ 2.6% showing 92.6% sensitivity and 99.0% NPV for ACS. In the derivation cohort, 45.2% of patients had PAV ConclusionThis study suggests that PAV up to 2.6% quantified by AI is associated with low-ACS risk in two independent patient cohorts. This cut-off may be helpful for clinical application of AI-guided CCTA analysis, which detects any plaque in up to 96–97% of patients.</p
Location-specific prognostic significance of plaque burden, stenosis, and plaque morphology in coronary artery disease
No full textAIMS: To investigate the location-specific prognostic significance of plaque burden, diameter stenosis, and plaque morphology. METHODS AND RESULTS: Patients without a documented cardiac history that underwent coronary computed tomography angiography (CCTA) for suspected coronary artery disease were included. Percentage atheroma volume (PAV), maximum diameter stenosis, and plaque morphology were assessed and classified into proximal, mid, or distal segments of the coronary tree. Major adverse cardiac events (MACE) were defined as death or non-fatal myocardial infarction. Among 2819 patients 267 events (9.5%) occurred during a median follow-up of 6.9 years. When adjusted for traditional risk factors and the presence of PAV in other locations, only proximal PAV was independently associated with MACE. However, PAV of the proximal segments was strongly correlated to PAV localized at the mid (R = 0.76) and distal segments (R = 0.74, P < 0.01 for both). When only adjusted for cardiovascular risk factors, the area under the curve (AUC) to predict MACE for proximal PAV was 0.73 (95% CI 0.69-0.76), which was similar compared with mid PAV (AUC 0.72, 95% CI 0.68-0.76) and distal PAV (AUC 0.72, 95% CI 0.68-0.76). Similar results were obtained using diameter stenosis instead of PAV. The presence of proximal low-attenuation plaque had borderline additional prognostic value. CONCLUSION: Proximal PAV was the strongest predictor of MACE when adjusted for cardiovascular risk factors and plaque at other locations. However, when the presence of plaque was only adjusted for cardiovascular risk factors, proximal, mid, and distal plaque localization showed a similar predictive ability for MACE.</p
Artificial Intelligence-based Coronary Plaque Quantification Using Coronary CT Angiography: Current Insights and Future Directions.
No full textItem does not contain fulltextOver the past decade, coronary CT angiography (CCTA) has seen major advancements in spatial and temporal resolution, as well as postprocessing software that now integrates artificial intelligence-based quantitative plaque (AI-QP) analysis tools. This review highlights the clinical significance of plaque quantification, examines the validation status of various AI-QP vendors, and discusses implications for patient care and outcomes. As plaque burden and progression are increasingly recognized as key prognostic indicators in patients with coronary artery disease (CAD), AI-QP has the potential to more accurately identify individuals at risk for adverse events and thereby influence patient management. However, several challenges must be addressed. The incremental prognostic value of AI-QP over established measures of plaque burden, such as the coronary artery calcium score, must be further established. For monitoring CAD progression, the reproducibility of AI-QP across CCTA scans must also be validated, and clinically meaningful thresholds for plaque progression need to be defined. Although AI-QP shows promise for improving risk stratification and guiding treatment, further evidence is needed to confirm its clinical utility and overcome barriers to widespread implementation in clinical practice. Keywords: CT-Coronary Angiography, Applications - CT, Artificial Intelligence © RSNA, 2025
Diagnostic performance of CCTA and CTP imaging for clinically suspected in-stent restenosis: A meta-analysis
No full textAims: The objective of this study is to conduct a meta-analysis to assess the diagnostic performance of Coronary Computed Tomography Angiography (CCTA) and a hybrid approach that incorporates Computed Tomography Perfusion (CTP) in addition to CCTA (CCTA þ CTP) for the detection of in-stent restenosis (ISR), as defined by angiography.
Methods: A comprehensive search of articles identified 18,513 studies. After removing duplicates, title/abstract screening, and full-text review, 17 CCTA and 3 CCTA þ CTP studies were included. Only studies using 64-slices multidetector computed tomography (CT) were considered eligible.
Results: The per-patient ISR prevalence was 43 %, with 92 % of stents fully interpretable with CCTA. Meta-analysis exhibited a per-stent CCTA (n ¼ 2674) sensitivity of 90 % (95 % CI; 84–94 %), specificity of 89 % (95 % CI; 86–92 %), positive likelihood ratio of 7.17 (95 % CI; 5.24–9.61), negative likelihood ratio of 0.17 (95 % CI; 0.10–0.25), and diagnostic odds ratio of 45.7 (95 % CI; 22.71–82.43). Additional sensitivity analyses revealed no influence of stent diameter or strut thickness on the diagnostic yield of CCTA. The per-stent diagnostic performance of CCTA þ CTP (n ¼ 752) did not show differences compared to CCTA.
Conclusions: With currently utilized scanners, CCTA and CCTA þ CTP demonstrated high diagnostic performance for in-stent restenosis evaluation. Consequently, a history of previous stent implantation should not be an argument to preclude using these methods in clinically suspected patients.Versión publicad
Warranty period of coronary computed tomography angiography and [15O]H2O positron emission tomography in symptomatic patients
No full textAims Data on the warranty period of coronary computed tomography angiography (CTA) and combined coronary CTA/positron emission tomography (PET) are scarce. The present study aimed to determine the event-free (warranty) period after coronary CTA and the potential additional value of PET.Method Patients with suspected but not previously diagnosed coronary artery disease (CAD) who underwent coronary CTA and/or and results [15O]H2O PET were categorized based upon coronary CTA as no CAD, non-obstructive CAD, or obstructive CAD. A hyperaemic myocardial blood flow (MBF) ≤ 2.3 mL/min/g was considered abnormal. The warranty period was defined as the time for which the cumulative event rate of death and non-fatal myocardial infarction (MI) was below 5%. Of 2575 included patients (mean age 61.4 ± 9.9 years, 41% male), 1319 (51.2%) underwent coronary CTA only and 1237 (48.0%) underwent combined coronary CTA/PET. During a median follow-up of 7.0 years 163 deaths and 68 MIs occurred. The warranty period for patients with no CAD on coronary CTA was ≥10 years, whereas patients with non-obstructive CAD had a 5-year warranty period. Patients with obstructive CAD and normal hyperaemic MBF had a 2-year longer warranty period compared to patients with obstructive CAD and abnormal MBF (3 years vs. 1 yearConclusion As standalone imaging, the warranty period for normal coronary CTA is ≥10 years, whereas patients with non-obstructive CAD have a warranty period of 5 years. Normal PET yielded a 2-year longer warranty period in patients with obstructive CAD
Diagnostic accuracy of non-invasive cardiac imaging modalities in patients with a history of coronary artery disease: a meta-analysis
No full textBackground The diagnostic performance of non-invasive imaging techniques for detecting obstructive coronary artery disease (CAD) in patients with a history of myocardial infarction or percutaneous coronary intervention has not been comprehensively evaluated. This meta-analysis assesses the diagnostic value of coronary CT angiography (CCTA), CCTA combined with CT perfusion (CCTA+CTP), cardiac MRI (CMR) and single-photon emission CT (SPECT) compared with invasive reference standards. Methods We systematically searched PubMed, Embase, Web of Science and the Cochrane Library from 2005 to September 2022 for prospective, blinded studies including populations with ≥50% prior CAD. Results We identified 18 studies encompassing 3265 patients, with obstructive CAD present in 64%. The per-patient sensitivity of CCTA (0.95; 95% CI 0.92 to 0.98), CCTA+CTP (0.93; 95% CI 0.84 to 0.98) and CMR (0.91; 95% CI 0.86 to 0.94) was high, while SPECT showed lower sensitivity (0.63; 95% CI 0.52 to 0.73). SPECT had higher specificity compared with CCTA (0.66; 95% CI 0.56 to 0.76 vs 0.37; 95% CI 0.29 to 0.46), but was comparable to CCTA+CTP (0.59; 95% CI 0.49 to 0.69) and CMR (0.69; 95% CI 0.53 to 0.81). The area under the curve for SPECT was the lowest (0.70; 95% CI 0.58 to 0.87), while CCTA (0.91; 95% CI 0.86 to 0.98), CCTA+CTP (0.89; 95% CI 0.73 to 1.00) and CMR (0.91; 95% CI 0.80 to 1.00) showed similar high values. Conclusions In patients with prior CAD, CCTA, CCTA+CTP and CMR demonstrated high diagnostic performance, whereas SPECT had lower sensitivity. These findings can guide the selection of non-invasive imaging techniques in this high-risk population. PROSPERO registration number CRD42022322348
Impact of cardiac history and myocardial scar on increase of myocardial perfusion after revascularization
No full textPurpose: We sought to assess the impact of coronary revascularization on myocardial perfusion and fractional flow reserve (FFR) in patients without a cardiac history, with prior myocardial infarction (MI) or non-MI percutaneous coronary intervention (PCI). Furthermore, we studied the impact of scar tissue. Methods: Symptomatic patients underwent [15O]H2O positron emission tomography (PET) and FFR before and after revascularization. Patients with prior CAD, defined as prior MI or PCI, underwent scar quantification by magnetic resonance imaging late gadolinium enhancement. Results: Among 137 patients (87% male, age 62.2 ± 9.5 years) 84 (61%) had a prior MI or PCI. The increase in FFR and hyperemic myocardial blood flow (hMBF) was less in patients with prior MI or non-MI PCI compared to those without a cardiac history (FFR: 0.23 ± 0.14 vs. 0.20 ± 0.12 vs. 0.31 ± 0.18, p = 0.02; hMBF: 0.54 ± 0.75 vs. 0.62 ± 0.97 vs. 0.91 ± 0.96 ml/min/g, p = 0.04). Post-revascularization FFR and hMBF were similar across patients without a cardiac history or with prior MI or non-MI PCI. An increase in FFR was strongly associated to hMBF increase in patients without a cardiac history or with prior MI/non-MI PCI (r = 0.60 and r = 0.60, p < 0.01 for both). Similar results were found for coronary flow reserve. In patients with prior MI scar was negatively correlated to hMBF increase and independently predictive of an attenuated CFR increase. Conclusions: Post revascularization FFR and perfusion were similar among patients without a cardiac history, with prior MI or non-MI PCI. In patients with prior MI scar burden was associated to an attenuated perfusion increase
