Impact of plaque characteristics on percutaneous coronary intervention-related microvascular dysfunction: insights from angiographic microvascular resistance and intravascular ultrasound.

Background: The correlation between percutaneous coronary intervention (PCI)-related microvascular dysfunction (MVD) and plaque characteristics remains unclear. To investigate this correlation and its prognosis, we assessed changes in MVD by angiographic microvascular resistance (AMR) and intracoronary ultrasound scans after PCI. Methods: We conducted a retrospective study that enrolled 250 patients with coronary artery disease between July 2016 and December 2018. We collected demographic characteristics, laboratory tests, coronary angiography (CAG) and intracoronary ultrasound findings. We calculated quantitative flow ratio (QFR) and AMR by CAG. The endpoint was vessel-oriented composite outcomes (VOCOs). Results: After 47 exclusions, we divided 203 cases into a deteriorated group (n=139) and an improved group (n=64) based on AMR change after PCI. Compared with the improved group, the deteriorated group had smaller lumen area [3.03 (interquartile range, 2.20-3.91) vs. 3.55 mm2 (interquartile range, 2.45-4.57), P=0.033], higher plaque burden [78.92% (interquartile range, 73.95-82.61%) vs. 71.93% (interquartile range, 62.70-77.51%), P<0.001], and higher proportion of lipidic components (13.86%±4.67% vs. 11.78%±4.41%, P=0.024). Of 186 patients who completed 4.81±1.55 years follow-up, 56 developed VOCOs. Receiver-operating characteristic (ROC) curve analysis showed post-PCI AMR and VOCOs correlation (area under the curve: 0.729, P<0.001). Multivariate regression analysis showed post-PCI AMR >285 mmHg·s/m correlated with adverse outcome (hazard ratio =4.350; 95% confidence interval: 1.95-9.703; P<0.001). Conclusions: Intravascular ultrasound (IVUS) imaging and AMR revealed an association of post-PCI MVD with a smaller lumen area, more severe plaque burden, and a higher percentage of lipidic components. Post-PCI MVD was an independent risk factor for poor prognosis.

Development and Validation of a Nomogram for Predicting Radial Artery Spasm During Coronary Angiography.

This study describes an attempt to develop a user-friendly nomogram incorporating psychological factors to individually predict the risk of radial artery spasm. Patients consecutively recruited between June 2020 and June 2021 constituted the development cohort for retrospective analysis of the development of a prediction model. Least absolute shrinkage and selection operator regression combined with clinical significance was employed to screen out appropriate independent variables. The model's discrimination and calibration were subsequently evaluated and calibrated by using the C-index, receiver operating characteristic (ROC) curve, and calibration plot. Decision curve analysis was also performed to evaluate the net benefit with the nomogram, and internal validation was assessed using bootstrapping validation. The predictors included in the risk nomogram included "body mass index ," "anxiety score," "duration of interventional surgery," "latency time (time spent waiting in the catheterization laboratory)," "vascular circuity (substantial changes in the curvature of vessels)," and "puncture number." The derived model showed good discrimination with an area under the ROC curve of .77, a C-index of .771 (95% CI: .72-.822) and good calibration. Decision curve analysis indicated that the nomogram provided a better net benefit than the alternatives.

Impact of guidewire selection and operator expertise on radiation exposure in transradial angiography.

BACKGROUND: Several studies have implied that the time of radiation exposure for patients and operators during the transradial approach for coronary angiography (TRA) is associated with the use of different guidewire or catheter and operator's finesse. This study aimed to assess the effects of non-hydrophilic or hydrophilic guidewire and operator expertise on fluoroscopy time and procedure time of TRA and further effects on the procedure safety. METHODS: A total of 1035 consecutive patients undergoing TRA were recruited prospectively and respectively divided into non-hydrophilic guidewire and hydrophilic guidewire group, or well-experienced group and less-experienced group. The primary endpoints were fluoroscopy time and procedure time. Secondary endpoints included contrast volume, cost, guidewire exchange, switchover and complications . RESULTS: TRA by non-hydrophilic guidewire group showed shorter fluoroscopy time and procedure time compared with hydrophilic guidewire group, similar results were found between well-experienced group and less-experienced group. Moreover, using of non-hydrophilic guidewire significantly reduced the incidence of hematoma and abnormal guidewie advancement, well-experienced group showed less dosage of contrast volume, lower incidence of radial artery spasm and frequency of guidewire exchange. CONCLUSIONS: TRA by non-hydrophilic guidewire and well-experienced operator can decrease radiation exposure of patients and operators through reducing the fluoroscopy time and procedure time and further increase procedure safety. These will contribute to the optimization of TRA procedure and promote its widely application.