An Overview of Computational Coronary Physiology Technologies Based on Medical Imaging and Artificial Intelligence.

This article reviews four new technologies for assessment of coronary hemodynamics based on medical imaging and artificial intelligence, including quantitative flow ratio (QFR), optical flow ratio (OFR), computational fractional flow reserve (CT-FFR) and artificial intelligence (AI)-based instantaneous wave-free ratio (iFR). These technologies use medical imaging such as coronary angiography, computed tomography angiography (CTA), and optical coherence tomography (OCT), to reconstruct three-dimensional vascular models through artificial intelligence algorithms, simulate and calculate hemodynamic parameters in the coronary arteries, and achieve non-invasive and rapid assessment of the functional significance of coronary stenosis. This article details the working principles, advantages such as non-invasiveness, efficiency, accuracy, limitations such as image dependency, and assumption restrictions, of each technology. It also compares and analyzes the image dependency, calculation accuracy, calculation speed, and operation simplicity, of the four technologies. The results show that these technologies are highly consistent with the traditional invasive wire method, and shows distinct advantages in terms of accuracy, reliability, convenience and cost-effectiveness, but there are also factors that affect accuracy. The results of this review demonstrates that AI-based iFR technology is currently one of the most promising technologies. The main challenges and directions for future development are also discussed. These technologies bring new ideas for the non-invasive assessment of coronary artery disease, and are expected to promote the technological progress in this field.

Efficacy and safety of a novel hexaspline pulsed field ablation system in patients with paroxysmal atrial fibrillation: the PLEASE-AF study.

AIMS: Pulsed field ablation (PFA) is an emerging non-thermal ablative modality demonstrating considerable promise for catheter ablation of atrial fibrillation (AF). However, these PFA trials have almost universally included only Caucasian populations, with little data on its effect on other races/ethnicities. The PLEASE-AF trial sought to study the 12-month efficacy and the safety of a multi-electrode hexaspline PFA catheter in treating a predominantly Asian/Chinese population of patients with drug-refractory paroxysmal AF. METHODS AND RESULTS: Patients underwent pulmonary vein (PV) isolation (PVI) by delivering different pulse intensities at the PV ostium (1800 V) and atrium (2000 V). Acute success was defined as no PV potentials and entrance/exit conduction block of all PVs after a 20-min waiting period. Follow-up at 3, 6, and 12 months included 12-lead electrocardiogram and 24-h Holter examinations. The primary efficacy endpoint was 12-month freedom from any atrial arrhythmias lasting at least 30 s. The cohort included 143 patients from 12 hospitals treated by 28 operators: age 60.2 ± 10.0 years, 65.7% male, Asian/Chinese 100%, and left atrial diameter 36.6 ± 4.9 mm. All PVs (565/565, 100%) were successfully isolated. The total procedure, catheter dwell, total PFA application, and total fluoroscopy times were 123.5 ± 38.8 min, 63.0 ± 30.7 min, 169.7 ± 34.6 s, and 27.3 ± 10.1 min, respectively. The primary endpoint was observed in 124 of 143 patients (86.7%). One patient (0.7%) developed a small pericardial effusion 1-month post-procedure, not requiring intervention. CONCLUSION: The novel hexaspline PFA catheter demonstrated universal acute PVI with an excellent safety profile and promising 12-month freedom from recurrent atrial arrhythmias in an Asian/Chinese population with paroxysmal AF. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT05114954.

Sirtuin 2 Exerts Regulatory Functions on Radiation-Induced Myocardial Fibrosis in Mice by Mediating H3K27 Acetylation of Galectin-3 Promoter.

Background: Sirtuin 2 (SIRT2) and galectin-3 have been shown to protect the heart against fibrosis. However, their impacts on radiation-induced myocardial fibrosis (RIMF) remain to be elucidated. To deepen this understanding, the current study sought to explore the effects of SIRT2 and galectin-3 on RIMF and the underlying mechanisms. Methods: Galectin-3 knockout mice were obtained, and a radiation-induced heart damage (RIHD) mouse model was induced by local radiation exposure to the heart. Lentivirus transfection was then performed, and heart function, fibrosis of heart tissues, and levels of SIRT2, galectin-3, and fibrosis-related markers collagen type-I/-III and matrix metalloproteinase (MMP)2/MMP9 were respectively assessed by echocardiography, hematoxylin-eosin and Masson staining, reverse transcription-quantitative polymerase chain reaction, Western blot, and immunofluorescence staining. Additionally, Western blot and chromatin immunoprecipitation were used to test H3K27 acetylation levels and the binding of H3K27ac to galectin-3, respectively. Results: After radiation exposure, heart tissues from the galectin-3 knockout mice had a smaller fibrotic area compared to normal mice, with reduced expression levels of collagen type-I/-III and MMP2/MMP9. SIRT2 was down-regulated and galectin-3 was up-regulated after RIHD treatment. The histone deacetylase inhibitor sirtinol promoted galectin-3 expression and H3K27 acetylation in a time-dependent manner, and increased H3K27ac enrichment in the galectin-3 promoter. Overexpression of SIRT2 down-regulated H3K27ac, collagen type-I/-III, and MMP2/MMP9 expression levels, and reduced the fibrotic area in mouse heart tissues. However, these effects were reversed by the additional overexpression of galectin-3. Conclusions: SIRT2 facilitates deacetylation of H3K27 to inhibit galectin-3 transcription, thus ameliorating RIMF in mice.

The active pulling technique to solve microcatheter-uncrossable lesions in retrograde chronic total occlusion percutaneous coronary intervention.

BACKGROUND: It is not uncommon to encounter retrograde microcatheter-uncrossable lesions in retro-recanalization of Chronic Total Occlusion (CTO) cases, existing solutions were time-consuming or complicated to operate. Therefore, the present study aimed to propose and evaluate the feasibility, safety of a novel technique termed Active Pulling retrograde microcatheter crossing Technique (APT) during retrograde CTO percutaneous coronary intervention (PCI). METHODS: We retrospectively collected retrograde CTO-PCI cases from February 2017 to April 2023, only cases with the retrograde wire successfully crossed the CTO lesion were analyzed. The baseline clinical characteristics, angiographic characteristics, procedural details, and in-hospital major adverse cardiac events (MACEs) were compared. RESULTS: A total of 80 CTO cases were divided into the APT group and the non-APT group according to whether the APT was applied in the procedure. The APT group had a higher rate of device success than the non-APT group (100% vs. 85%, P = 0.013), with shorter duration (5.3 ± 3.8 vs. 18.6 ± 5.9 min, P < 0.001) and a smaller number of retrograde microcatheters were used (P < 0.001). In the APT group, the average air kerma radiation exposure was lower (2.7 ± 1.2 vs. 4.3 ± 1.7 Gy, P < 0.001), the fluoroscopy time (69.0 ± 15.0 vs. 88.1 ± 18.9 min, P < 0.001) and the procedure time (116.2 ± 22.2 vs. 131.6 ± 28.7 min, P = 0.009) was shorter than the non-APT group. The technical success rate of both groups reached 100% while the procedure success rate was higher in the APT group than the non-APT group (100% vs. 85%, P = 0.13). CONCLUSIONS: The APT is an easy and safe technique that can greatly improve procedural efficiency without adding other instruments, and allows the retrograde microcatheter to quickly crossing the CTO body after successful retrograde wire externalization.

Prediction of the left ventricular mass index in hypertensive patients using the product of red cell distribution width and mean corpuscular volume.

The product of red cell distribution width (RDW) and mean corpuscular volume (MCV) has been identified as an indicator of target organ damage in cases of hypertension. However, the role of the RDW-MCV product in assessing carotid alteration, renal damage, and left ventricular hypertrophy in patients with hypertension has not been elucidated. In this cross-sectional study, a total of 1115 participants with hypertension were included. The RDW and MCV at admission were measured using an automated hematology analyzer. Organ damage was determined by the left ventricular mass index (LVMI), carotid intima-media thickness, and estimated glomerular filtration rate. The prevalence rates of carotid alteration and left ventricular hypertrophy were 57.0% and 18.0%, respectively. A higher RDW-MCV product and RDW were observed in hypertensive patients who developed carotid alteration. After adjusting for potential confounding factors, the correlations of the RDW-MCV product (P = .285) and RDW (P = .346) with carotid alteration were not significant. Moreover, the analysis of variance showed no significant correlation between RDW and LVMI (P = .186). However, the RDW-MCV product was higher in individuals with a high LVMI compared to those with a normal LVMI. Multivariable linear regression analysis revealed that the RDW-MCV product was independently associated with the LVMI (ß = 2.519, 95% CI: 0.921-4.116; P = .002), but not the estimated glomerular filtration rate (ß = -0.260, 95% CI: -2.031-1.511; P = .773). An elevated RDW-MCV product may be a predictor for left ventricular hypertrophy in patients with hypertension.

Hyperhomocysteine promotes cataract development through mTOR-mediated inhibition of autophagy and connexins expression.

AIM: Hyperhomocysteine has been recognized as an independent risk factor of multiple diseases, including several eye diseases. In this study, we aim to investigate whether increased homocysteine (Hcy) is related to cataracts, and to explore whether dysregulation of mTOR-mediated autophagy and connexin expression are underlying mechanisms. METHOD: We first developed a method of liquid chromatography tandem mass spectrometry to accurately measure serum concentrations of Hcy in 287 cataract patients and 334 healthy controls. Next, we treated human lens epithelial (HLC-B3) cells with Hcy at different concentrations and durations, and then analyzed expression of autophagy-related markers and connexins, as well as phosphorylated mTOR (p-mTOR) in these cells by Western blotting. Formation of autophagic vacuoles and intracellular Ca2+ in the Hcy-treated cells were observed by fluorescence microscopy. Further, we performed a rescue experiment in the Hcy-treated HLC-B3 cells by pre-incubation with rapamycin, an mTOR inhibitor. RESULTS: The serum levels of Hcy in patients with cataracts were significantly increased compared to those in healthy controls. In cultured HLC-B3 cells, expression of autophagy related markers (LC3B and Beclin1) and connexins (Cx43 and Cx50) was inhibited by Hcy treatment in a dose- and duration-dependent manner. Accumulation of Ca2+ in the Hcy-treated lens epithelial cells was observed as a consequence of reduced connexin expression. Meanwhile, expression of p-mTOR increased, representing up-regulation of the mTOR pathway. Importantly, inhibition of autophagy and connexin expression due to hyperhomocysteine was rescued via mTOR suppression by pretreatment with rapamycin in HLC-B3 cells. CONCLUSION: Our results demonstrate that hyperhomocysteine might promote cataract development through two mTOR-mediated pathways in the lens epithelial cells: 1) dysregulation of autophagy and 2) accumulation of intracellular calcium via decreased connexin expression.

Safety and efficacy of the DragonFly system for transcatheter valve repair of degenerative mitral regurgitation: one-year results of the DRAGONFLY-DMR trial.

BACKGROUND: Severe degenerative mitral regurgitation (DMR) can cause a poor prognosis if left untreated. For patients considered at prohibitive surgical risk, transcatheter edge-to-edge repair (TEER) has become an accepted alternative therapy. The DragonFly transcatheter valve repair system is an innovative evolution of the mitral TEER device family to treat DMR. AIMS: Herein we report on the DRAGONFLY-DMR trial (ClinicalTrials.gov: NCT04734756), which was a prospective, single-arm, multicentre study on the safety and effectiveness of the DragonFly system. METHODS: A total of 120 eligible patients with prohibitive surgical risk and DMR ≥3+ were screened by a central eligibility committee for enrolment. The study utilised an independent echocardiography core laboratory and clinical event committee. The primary endpoint was the clinical success rate, which measured freedom from all-cause mortality, mitral valve reintervention, and mitral regurgitation (MR) >2+ at 1-year follow-up. RESULTS: At 1 year, the trial successfully achieved its prespecified primary efficacy endpoint, with a clinical success rate of 87.5% (95% confidence interval: 80.1-92.3%). The rates of major adverse events, all-cause mortality, mitral valve reintervention, and heart failure hospitalisation were 9.0%, 5.0%, 0.8%, and 3.4%, respectively. MR ≤2+ was 90.4% at 1 month and 92.0% at 1 year. Over time, left ventricular reverse remodelling was observed (p<0.05), along with significant improvements in the patients' functional and quality-of-life outcomes, shown by an increase in the New York Heart Association Class I/II from 32.4% at baseline to 93.6% at 12 months (p<0.001) and increased Kansas City Cardiomyopathy Questionnaire (KCCQ) score of 31.1±18.2 from baseline to 12 months (p<0.001). CONCLUSIONS: The DRAGONFLY-DMR trial contributes to increasing evidence supporting the safety and efficacy of TEER therapy, specifically the DragonFly system, for treating patients with chronic symptomatic DMR 3+ to 4+ at prohibitive surgical risk.