Impact of Isolated Coronary Microvascular Disease Diagnosed Using Various Measurement Modalities on Prognosis: An Updated Systematic Review and Meta-Analysis.

INTRODUCTION: The main aim of this study was to investigate the impact of isolated coronary microvascular disease (CMD) as diagnosed via various modalities on prognosis. METHODS: A systematic literature review of PubMed, Embase, and Cochrane Library databases was conducted to identify relevant studies published up to March 2023. Included studies were required to measure coronary microvascular function and report outcomes in patients without obstructive coronary artery disease (CAD) or any other cardiac pathological characteristics. The primary endpoint was all-cause mortality, and the secondary endpoint was a major adverse cardiac event (MACE). Pooled effects were calculated using random effects models. RESULTS: A total of 27 studies comprising 18,204 subjects were included in the meta-analysis. Indices of coronary microvascular function measurement included coronary angiography-derived index of microcirculatory resistance (caIMR), hyperemic microcirculatory resistance (HMR), coronary flow reserve (CFR), and so on. Patients with isolated CMD exhibited a significantly higher risk of mortality (OR: 2.97, 95% CI, 1.91-4.60, p < 0.0001; HR: 3.38, 95% CI, 1.77-6.47, p = 0.0002) and MACE (OR: 5.82, 95% CI, 3.65-9.29, p < 0.00001; HR: 4.01, 95% CI, 2.59-6.20, p < 0.00001) compared to those without CMD. Subgroup analysis by measurement modality demonstrated consistent and robust pooled effect estimates in various subgroups. CONCLUSION: CMD is significantly associated with an elevated risk of mortality and MACE in patients without obstructive CAD or any other identifiable cardiac pathologies. The utilization of various measurement techniques may have potential advantages in the management of isolated CMD.

Effect of indobufen vs. aspirin on platelet accumulation in patients with stable coronary heart disease after percutaneous coronary intervention: An open-label crossover study.

Purpose: This study compared the effect of indobufen with that of aspirin on platelet function in patients with stable coronary heart disease after percutaneous coronary intervention (PCI). Methods: Patients with stable coronary heart disease who had undergone PCI and received dual antiplatelet therapy (aspirin 100 mg + clopidogrel 75 mg once daily) for at least 12 months were allocated to receive indobufen 100 mg twice daily + clopidogrel 75 mg once daily, clopidogrel 75 mg once daily alone, indobufen 100 mg twice daily alone, and aspirin 100 mg once daily alone for 1 month each in an open-label crossover manner. Platelet function was assessed by using the rates of arachidonic acid (AA)-induced platelet aggregation (AA-PAR) and adenosine diphosphate (ADP)-induced platelet aggregation (ADP-PAR) measured by light transmission aggregometry, the platelet reactivity index measured by vasodilator-stimulated phosphoprotein (PRI-VASP), and the plasma and urinary thromboxane B2 (TXB2) concentrations recorded at baseline and during each treatment phase. Results: Of 56 patients enrolled, 52 completed the study. The AA-PAR was lower in the indobufen alone group than in the aspirin alone group [5.21% (3.39, 7.98) vs. 5.27% (4.06, 6.60), p = 0.038], while biologically, a difference of 0.06% may represent no significant difference; there was no significant between-group difference in the plasma [531.16 pg/ml (203.89, 1035.06) vs. 373.93 pg/ml (194.04, 681.71), p = 0.251] or urinary [3951.97 pg/ml (2006.95, 6077.01) vs. 3610.48 pg/ml (1664.60, 6247.61), p = 0.717] TXB2 concentration. When the aspirin + clopidogrel group and indobufen + clopidogrel group were compared, similar results were found for AA-PAR [3.97% (3.05, 5.12) vs. 3.83% (3.10, 5.59), p = 0.947] and both plasma [849.47 pg/ml (335.96, 1634.54) vs. 455.41 pg/ml (212.47, 1489.60), p = 0.629], and urinary [4122.97 pg/ml (2044.96, 7459.86) vs. 3812.81 pg/ml (1358.95, 6021.07), p = 0.165] TXB2 concentrations. ADP-PAR was lower in the clopidogrel alone group than in the indobufen alone group (47.04% ± 16.89 vs. 61.7% ± 10.50, p < 0.001), as was PRI-VASP (66.53% ± 18.06 vs. 77.72% ± 19.87, p = 0.002). Conclusion: These findings suggest that indobufen has antiplatelet effects similar to those of aspirin in patients with stable coronary heart disease after PCI, and may be an alternative for patients with aspirin intolerance after coronary stenting.

Five-year comparative study of thin-strut rapamycin-eluting bioabsorbable scaffold with metallic drug-eluting stent in porcine coronary artery.

Objectives: Using quantitative coronary angiography (QCA), optical coherence tomography (OCT), histomorphometry, and pharmacokinetics, this study tried to evaluate the safety and efficacy of Biomagic rapamycin-eluting bioabsorbable scaffold (BVS) in non-atherosclerotic porcine coronary arteries. Background: Biomagic BVS is a new generation of thin-strut bioabsorbable scaffold. We conducted comparative study detailing pathological response, safety and efficacy of Biomagic BVS and the Firebird2 rapamycin-eluting cobalt-based alloy stent (DES) in a porcine coronary artery model. The animals were followed up at 14 days, 1, 3, 6, 12, 18, 24, 30, 36, 42, 48, 54, and 60 months after stent implantation. Methods: A total of 143 devices (95 Biomagic and 48 Firebird2) were implanted in 2 or 3 main coronary arteries of 76 nonatherosclerotic swine and examined by QCA, OCT, light microscopy, and pharmacokinetics analyses at various time points. Results: Vascular responses to Biomagic and Firebird2 were largely comparable at all time points, with struts being sequestered within the neointima. The degree of inflammation of both devices was mild to moderate, although the Biomagic score was higher at 14 days to 24 months. However, there was no statistical difference between the two groups except 14 days. At each follow-up time point, the percentage of area stenosis in the Biomagic group was greater than that in the Firebird 2 group, but there was no statistical difference between the two groups at 3 and 12 months. The extent of fibrin deposition was similar between Biomagic and Firebird2, which peaked at 1 month and decreased rapidly thereafter. Pharmacokinetic study showed that coronary tissue sirolimus concentration remained above 2 ng/mg of tissue at 28 day. Histomorphometry showed expansile remodeling of Biomagic-implanted arteries starting after 12 months, and lumen area was significantly greater in Biomagic than Firebird2 at 36 and 42 months. These changes correlated with dismantling of Biomagic seen after 12 months. OCT images confirmed that degradation of Biomagic was complete by 36 months. Conclusions: Biomagic demonstrates comparable long-term safety to Firebird2 in porcine coronary arteries with mild to moderate inflammation. Although Biomagic was associated with greater percent stenosis relative to Firebird2 within 36 months, expansile remodeling was observed after 12 months in Biomagic with significantly greater lumen area at ≥36 months. Scaffold resorption is considered complete at 36 months.

Association Between Circulating Proprotein Convertase Subtilisin/Kexin Type 9 Concentrations and Cardiovascular Events in Cardiovascular Disease: A Systemic Review and Meta-Analysis.

Background: A large amount of evidence suggests that proprotein convertase subtilisin/Kexin type 9 (PCSK9) inhibitors have clinical benefits in patients with cardiovascular disease (CVD). However, whether PCSK9 concentrations predict future cardiovascular (CV) events remains unclear. Methods: We conducted a meta-analysis to investigate the ability of PCSK9 concentrations to predict future CV events in patients with established CVD. A comprehensive search of electronic databases was conducted in June 2021. We included relative risk (RR) estimates with 95% CI or events of interest. Results: Eleven cohort studies including 8,471 patients with CVD were enrolled. The pooled RR of CV events for the increase in the circulating baseline PCSK9 concentrations by 1 SD showed a positive association in a random-effect model (RR 1.226, 95% CI: 1.055-1.423, P = 0.008). Similarly, the risk of the total CV events increased by 52% in the patients in the highest tertile compared with those in the lowest tertile of circulating PCSK9 concentrations (RR 1.523, 95% CI: 1.098-2.112, P = 0.012). The association between PCSK9 and CV events was stronger in stable patients with CVD, patients treated with statins, and Asian patients. Conclusions: High PCSK9 concentrations are significantly related to the increased risk of future CV events. These results enrich the knowledge of PCSK9 function and suggest the further possible clinical role of PCSK9 inhibitors.