BACKGROUND:Coronary microvascular dysfunction (CMD) is common among patients with angina with non-obstructive coronary artery disease (ANOCA) and leads to poorer clinical outcomes. Exercise stress testing (EST) was shown to have a high specificity for detecting CMD. However, the relationship between diagnosing CMD using different invasive physiological parameters and thresholds and the association between EST findings and the endotype of CMD remains unknown. METHODS:This multicentre, prospective cohort study enrolled 117 patients with ANOCA who underwent EST prior to invasive coronary angiography with functional assessment to measure coronary flow reserve (CFR), the index of microvascular resistance (IMR) and microvascular resistance reserve (MRR)=(CFR/FFR)×(Pa rest/Pa hyper). CMD was classified using multiple criteria, including MRR <3.0, CFR <2.5 and CFR <2.0 or IMR ≥25. Diagnostic sensitivity and specificity and the accuracy of EST findings (exercise-induced chest discomfort, ischaemic ECG changes and exercise intolerance) for diagnosing CMD were assessed. RESULTS:The prevalence of CMD was similar under all three definitions. However, structural CMD was more common using MRR <3.0. Ischaemic ECG changes during EST showed an excellent diagnostic accuracy of 86.3% (78.7-92.0%) for detecting CMD, with a sensitivity and specificity of 86.2% (68.3-96.1%) and 86.4% (77.4-92.8%), respectively. Exercise-induced chest discomfort also had a good diagnostic accuracy of 76.1% (95% CI 67.3% to 83.5%); however, it offered no additional value when added to ischaemic ECG changes. EST preferentially identified structural CMD, while functional CMD was more frequently missed. CONCLUSIONS:Ischaemic ECG changes during EST performed immediately before invasive functional assessment demonstrated excellent diagnostic accuracy for identifying patients with CMD, particularly the structural endotype. TRIAL REGISTRATION NUMBER:NCT05841485.

Photon-counting detector computed tomography (PCD-CT) is an emerging advanced CT technology that differs from conventional energy-integrating detector CT (EID-CT) scanners in its ability to directly convert incident X-ray photon energies into electrical signals. Since its commercial market introduction in 2021, several studies have identified advantages of this new technology in the field of cardiovascular imaging, including improved image quality due to an enhanced contrast-to-noise ratio, superior spatial resolution, reduced artefacts, and a reduced radiation dose. Nonetheless, radiation exposure with PCD-CT can vary depending on the acquisition mode and protocol used, highlighting the importance of tailored optimization in clinical practice. In particular, this new technology appears feasible in patients with a high plaque burden independent of morphology, unravelling new phenotypes of plaque, in patients with stents due to the improved visualization of the coronary in-stent lumen, potentially expanding the scope of CT. Early studies and clinical experience support these potential applications of PCD-CT in cardiovascular diagnostics, suggesting workflow optimization and improved patient management. In this review, the authors aim to describe the role of PCD-CT not only in the exclusion of coronary artery disease, grading of coronary stenosis and plaque imaging, but also in evaluation of cardiac chambers and myocardium for tissue characterization trying to understand whether PCD-CT has yet led to a true revolution and significant progress in cardiovascular imaging.

BACKGROUND:The influence of left ventricular ejection fraction (LVEF) on clinical outcomes in patients treated with drug-coated balloons (DCBs) versus drug-eluting stents (DES) for de novo coronary lesions remains uncertain. METHODS:REC-CAGEFREE I was an investigator-initiated, non-inferiority trial conducted at 43 sites in China, randomizing 2272 patients to paclitaxel-coated balloons with optional rescue stenting or to sirolimus-eluting stents. In this pre-specified subgroup analysis, 2194 patients with available baseline LVEF were stratified into LVEF <55% and LVEF ≥55%. The primary endpoint was the device-oriented composite endpoint (DoCE; including cardiovascular death, target-vessel myocardial infarction, and clinically and physiologically indicated target lesion revascularization) at 3 years. RESULTS:Among 2194 patients, 402 (18.3%) had an LVEF <55%, and 1792 (81.7%) had an LVEF ≥55%. At 3 years, the risk of DoCE was numerically higher in patients with an LVEF <55% versus LVEF ≥55% (9.0% vs. 6.1%; P=0.237). A significant treatment-by-LVEF interaction was observed for DoCE (Pinteraction=0.033). In patients with an LVEF <55%, DoCE occurred in 28/206 (13.7%) and 8/196 (4.2%) patients in the DCB and DES groups (DifferenceIPTW: 7.19%, 95% CI: 1.89% to 12.48%, P=0.008), respectively; in patients with an LVEF ≥55%, DoCE occurred in 62/886 (7.0%) and 47/906 (5.2%) patients in the DCB and DES groups (DifferenceIPTW: 1.93%, 95% CI: -0.37% to 4.23%, P=0.101), respectively. CONCLUSIONS:Baseline LVEF may modify clinical outcomes after DCB versus DES for de novo coronary artery disease, with excess risk of DoCE with DCB mainly observed in patients with LVEF <55%. These exploratory findings should be interpreted cautiously. CLINICAL TRIAL REGISTRATION:www. CLINICALTRIALS:gov; number, NCT04561739.

BACKGROUND & AIMS:Although lipoprotein(a) [Lp(a)] is an established independent risk factor for atherosclerotic cardiovascular disease (ASCVD) in primary prevention settings, it remains unclear whether Lp(a) contributes to an increased risk of adverse cardiovascular events in patients with established ASCVD. METHODS:The current analysis combines the ATHEROREMO and IBIS-3 observational studies, which together enrolled 798 patients undergoing coronary angiography for stable angina pectoris or acute coronary syndrome. Intravascular ultrasound (IVUS) and near-infrared spectroscopy were performed to assess coronary plaque characteristics in a non-culprit study segment. Regression models were applied to relate Lp(a) to coronary plaque characteristics and long-term (up to 10 year) clinical outcomes. Lp(a) was analysed both as a continuous and categorical variable (using 75 nmol/L and 125 nmol/L as threshold). RESULTS:Mean age of the patients was 61.6 years (10.8); 75% were male; 19% had elevated Lp(a) levels (>125 nmol/L). Patients with Lp(a) > 125 nmol/L had a significantly higher prevalence of hypercholesterolemia and prior percutaneous coronary intervention. These patients demonstrated higher IVUS-derived plaque burden (40.7% (±11.5) vs. 38.6% (±10.7), p = 0.028), though no associations were found with other plaque characteristics, e.g. minimum lumen area, lipid core burden index and thin-cap fibroatheroroma. No association was found between Lp(a) and -5-year major adverse cardiac events (HR 1.06, 95% CI: 0.70-1.60, p = 0.78) and 10-year all-cause mortality (HR 0.63, 95% CI: 0.38-1.06, p = 0.78). CONCLUSIONS:Among patients with established ASCVD, Lp(a) was associated with plaque burden, supporting evidence that relates Lp(a) to atherosclerotic disease. However, Lp(a) was not associated with long-term mortality or cardiac adverse events in these patients.

The anatomical and pathophysiological characteristics of coronary artery disease vary between the sexes. This study investigated the impact of sex on outcomes in patients with de novo coronary artery lesions treated with drug-coated balloons (DCB) or drug-eluting stents (DES). REC-CAGEFREE I was an investigator-initiated, non-inferiority trial conducted at 43 sites in China from Feb 5, 2021, to May 1, 2022, which randomized 2,272 patients for treating de novo coronary lesions, regardless of vessel diameter. After successful lesion pre-dilatation, eligible patients were randomized (1:1) to either DCB angioplasty with the option of rescue stenting or intended DES deployment. In this prespecified subgroup analysis, patients were analyzed by sex based on their medical records. The primary endpoint was device-oriented composite endpoint (DoCE), including cardiovascular death, target-vessel myocardial infarction, and clinically and physiologically indicated target lesion revascularization at 2 years. Between-group differences were compared by Cox proportional-hazards models, and imbalances in baseline characteristics were adjusted with inverse probability of treatment weighting (IPTW). The analyses were conducted in the intention-to-treat population. A total of 2,272 participants underwent randomization, of which 698 (30.7

BACKGROUND:Supersaturated oxygen (SSO2) is a novel adjunctive treatment aims to reduce reperfusion injury after primary percutaneous coronary intervention (PCI) in ST-segment elevation myocardial infarction (STEMI). We conducted this study to evaluate the efficacy and safety of SSO2 therapy in patients with STEMI. METHODS:Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, we systematically searched Cochrane Central, Embase, PubMed, Scopus, and Web of Science for studies comparing SSO2 therapy post-PCI with PCI alone in adults with STEMI. Primary efficacy outcomes were infarct size and all-cause death. A random-effects model was used for analysis. RESULTS:Six unique studies that enrolled 1591 patients were included [518 (32.5%) of whom received SSO2]. SSO2 therapy was associated with a reduction in infarct size compared with the control group [mean difference = -4.7% of left ventricular mass, 95% confidence interval (CI): -8.3 to -1.1%; P = 0.01], with the greatest benefit observed in patients reperfused within 6 h of symptom onset (mean difference = -6.0% of left ventricular mass, 95% CI: -8.9 to -3.0%). SSO2 therapy was also associated with reduced left ventricular end-systolic volume (mean difference = -19.9 ml, 95% CI: -33.7 to -6.2). The between-group difference in all-cause mortality was NS (P = 0.58); however, an association between SSO2 use and reduced all-cause death was present in the two studies with long-term (1-year) follow-up (risk ratio = 0.10, 95% CI: 0.01-0.77). No safety concerns were identified. CONCLUSION:SSO2 administration in patients with STEMI after primary PCI was safe and was associated with reduced infarct size, particularly when administered within 6 h of symptom onset. This myocardial salvage was associated with improvement in left ventricular function Further randomized trials are needed to definitively establish the impact of SSO2 on mortality and heart failure.

BACKGROUND:The clinical impact of angiography-based, computational pressure-flow dynamics derived FFR (caFFR) after paclitaxel‑coated balloon (DCB) angioplasty remains unclear. AIMS:To investigate the prognostic value of post-procedural caFFR in the treatment of in-stent restenosis (ISR) with DCB. METHODS:Consecutive patients undergoing DCB angioplasty for ISR at Xijing Hospital, China, between December 2015 and December 2019 were prospectively enrolled. The primary endpoint was vessel-oriented composite endpoint (VoCE), defined as a composite of vessel-related cardiovascular death, target-vessel myocardial infarction (TV-MI), and ischemia-driven target vessel revascularization (ID-TVR) at 3-year, assessed at the vessel level. RESULTS:A total of 1055 vessels treated with DCB were screened, and the post-procedural caFFR was analyzable in 999 (94.7%). At 3-year, 149 VoCE (14.9%) and 98 ID-TVR (9.8%) events occurred. Maximally-selected log-rank statistics respectively identified post-procedural caFFR value of 0.87 and post-procedural %DS of 28 as the optimal cutoff points to predict VoCE. Post-procedural caFFR demonstrates the superior predictive ability for VoCE compared to post-procedural %DS (NRI: 7.4%, p < 0.001). A negative correlation was discerned between post-procedural caFFR value and VoCE (HRper 0.1 increase: 0.72, 95% CI: 0.53-0.98, p = 0.039). Post-procedural caFFR ≤ 0.87 group was associated with a 1.5-fold increase in the risk of VoCE (HRIPTW: 1.53, 95% CI: 1.02-2.29) and a 1.8-fold increase in ID-TVR (HRIPTW: 1.82, 95% CI: 1.15-2.89). CONCLUSIONS:A higher post-procedural caFFR value is associated with improved vessel-related clinical outcomes in patients of ISR treated by DCB. Achieving a post-procedural caFFR value of 0.87 in the treated vessels may represent a reasonable procedural goal. TRIAL REGISTRATION:Clinicaltrial.gov identifier: NCT05133921.

Almost half a century ago, cardiac surgeons introduced the concept of prosthesis–patient mismatch (PPM), which was defined by indexing the effective orifice area (EOA) to body surface area. Although PPM has demonstrated strong prognostic value following surgical aortic valve replacement (SAVR), its significance in transcatheter aortic valve replacement (TAVR) remains uncertain. In this review, we revisit the concept of PPM and explore the methodological and clinical challenges in its application. Special focus is given to the limitations in interpreting EOA and indexed EOA (EOAi), including flow dependency and imaging variability. We also review the literature evaluating the association between PPM and clinical outcomes after SAVR and TAVR. Finally, we discuss a potential role of alternative metric such as the fitting index.

Patient obesity is now a common characteristic in the cardiac catheterisation laboratory, yet its impact on radiation exposure remains under-recognised. Increased body mass index impairs X-ray penetration, prompting fluoroscopy systems to increase radiation output to maintain image quality. Consequently, patients with obesity receive substantially higher radiation doses across coronary, electrophysiological, haemodynamic, and structural heart procedures, while operators experience disproportionate increases in scatter radiation, creating cumulative occupational risk. Obesity also increases procedural complexity through more challenging vascular access, prolonged fluoroscopy, suboptimal shielding, and steeper imaging projections, further amplifying radiation burden. This review synthesises current evidence demonstrating obesity as a major procedural determinant of radiation exposure and proposes a practical obesity-aware framework incorporating fluoroscopy optimisation, shielding strategies, real-time dosimetry, enhanced radiation protection devices, workflow adaptations, and institutional quality improvement. Recognising body habitus as a core procedural variable is essential to improving radiation safety for both patients and healthcare workers while informing future obesity-specific radiation protocols.

BACKGROUND:For long coronary lesions, drug-coated balloons (DCBs) might be an attractive alternative compared with drug-eluting stents (DES); however, supporting evidence remains scarce. AIMS:To compare the efficacy of DCBs versus DES for treating long de novo coronary lesions. METHODS:REC-CAGEFREE I was a non-inferiority trial conducted at 43 sites in China, which randomized 2272 patients to paclitaxel-coated balloon angioplasty with the option of rescue stenting or sirolimus-eluting stents for treating de novo lesions, regardless of vessel diameter. In this pre-specified subgroup analysis, patients were stratified by quantitative coronary angiography-assessed lesion length into short (< 20 mm) and long (≥ 20 mm) groups. The primary endpoint was a device-oriented composite endpoint (DoCE, including cardiovascular death, target vessel myocardial infarction, or clinically and physiologically-indicated target lesion revascularization) at 3 years. RESULTS:2,223 (97.8%) participants with available angiograms were included, of which 302 (13.6%) had long lesions and 1921 (86.4%) had short lesions. At 3 years, DoCE occurred in 24/302 (8.0%) and 121/1921 (6.3%) patients in long and short groups, respectively. In the long lesions group, DoCE occurred in 14/121 (11.6%) and 10/181 (5.6%) in the DCBs and DES groups, respectively (HRIPTW: 2.46, 95% CI: 1.07-5.67, p = 0.034). In the short lesions group, DoCE occurred in 75/983 (7.7%) and 46/938 (4.9%) in the DCBs and DES groups, respectively (HRIPTW: 1.52, 95% CI: 1.03-2.22, p = 0.033). No significant interaction was observed between lesion length and DES/DCBs (Pinteraction = 0.460). CONCLUSION:DCBs were associated with a higher risk of DoCE compared to DES for treating de novo lesions, regardless of lesion length.

Background Evidence regarding the link between imaging modality and stroke prevention outcomes of left atrial appendage occlusion is currently lacking. Methods The RECORD (Registry to Evaluate Chinese Real‐World Clinical Outcomes in Patients With AF Using the WATCHMAN Left Atrial Appendage Closure Technology) trial prospectively enrolled 3096 consecutive patients undergoing left atrial appendage occlusion from 39 Chinese centers between April 1, 2019, and October 31, 2020. In the current analyses, patients were stratified into the echocardiographic guidance (transesophageal echocardiography/intracardiac echocardiography) group and the fluoroscopy‐only group. The primary end point was the composite end point of death, stroke, or systemic embolism at 3 years. Outcomes were estimated using the Kaplan–Meier method. Inverse probability of treatment weighting and 1:1 propensity score matching were performed to calculate hazard ratios (HRs) for each outcome at the time of interest. Results Among 3096 participants, 2603 (84.1%) underwent transesophageal echocardiography/intracardiac echocardiography–guided procedures and 493 (15.9%) underwent fluoroscopy‐only guided procedures. Before discharge, procedural complications occurred in 34 patients (1.4%) in the transesophageal echocardiography/intracardiac echocardiography group and 3 patients (0.6%) in the fluoroscopy‐only group (inverse probability of treatment weighting–adjusted absolute difference, −0.67 [95% CI, −1.39 to 0.05], P =0.066). At 3‐year follow‐up (completed by 2989 patients, 97.0%), the primary end point occurred in 269 (10.5%) patients in the transesophageal echocardiography/intracardiac echocardiography group and 52 (10.6%) patients in the fluoroscopy‐only group (inverse probability of treatment weighting–adjusted HR, 1.13 [95% CI, 0.81–1.57], P =0.469). Ischemic stroke was comparable between groups (3.0% versus 4.1%, inverse probability of treatment weighting–adjusted HR, 1.66 [95% CI, 0.95–2.89], P =0.073). These findings remained consistent across patient risk profiles and operator experience levels. Conclusions Fluoroscopy‐only guidance, without compromising long‐term stroke prevention efficacy, may serve as a streamlined and potentially accessible alternative for left atrial appendage occlusion procedures performed with the first‐generation WATCHMAN 2.5 device, and these findings apply to select patients and experienced centers. Registration URL: https://www.clinicaltrials.gov ; Unique Identifier: NCT03917563.

BACKGROUND AND AIMS:To clarify the relationship between haemodynamic milieu and lipid core plaques among culprit and non-culprit coronary vessels. METHODS:A total of 45 vessels from 20 patients with acute coronary syndrome who underwent invasive coronary angiography were prospectively enrolled for additional near-infrared spectroscopy intravascular ultrasound (NIRS-IVUS) imaging to quantify lipid plaque content. Haemodynamics assessments between culprit (n = 19, one excluded due to suboptimal angiography) and non-culprit (n = 25) vessels were performed using three-dimensional arterial reconstructions derived from fused NIRS-IVUS and quantitative coronary angiography imaging. RESULTS:Culprit vessels were characterised by a higher probability of lipid core containing coronary plaques (0.00 [interquartile range, IQR: 0.00-0.278] vs. 0.00 [0.00-0.119], p ≪ 0.05). The greatest haemodynamics differentiation between the two groups, in descending order, was observed in transverse endothelial shear stress (transESS), oscillatory shear index (OSI), and elevated blood viscosity (EBV). In mixed logistic regression, after adjusting for other haemodynamic metrics, culprit vessels exhibited decreasing odds of moderate-to-high OSI (odds ratio [OR] 0.484, 95% confidence interval [CI] 0.304-0.770, p = 0.002 and OR 0.578, 95% CI 0.339-0.985, p = 0.044, respectively), as was moderate transESS (OR 0.440, 95% CI 0.276-0.702, p < 0.001), but increasing odds of moderate-to-high EBV (OR 2.030, 95% CI 1.180-3.491, p = 0.010 and OR 4.373, 95% CI 2.017-9.479, p < 0.001, respectively). CONCLUSIONS:This study observed elevated blood viscosity within culprit vessels, as a potentially underexplored feature of plaque vulnerability. Our findings suggest that blood viscosity is associated with vessel-specific differences in lipid core plaque, though the small sample size means these findings should be considered hypothesis-generating.