The Role of Coronary Physiology Assessment in the Diagnosis and Treatment of Stable Angina. Dive Inside Recent Findings of Diffuse Coronary Disease Treatment.

Coronary physiology is widely used to assess epicardial coronary lesions in patients with stable angina. Based on the available evidence, physiology plays a crucial role in diagnosing and treating patients. There have been invasive methods for determining cardiac physiology, such as fractional flow reserve and instantaneous wave-free ratio. Still, new non-invasive approaches provide extra anatomical information, such as fractional flow reserve computed tomography (FFR-CT) based on computed tomography and physiology based on angiography. Even though FFR-guided percutaneous coronary intervention (PCI) is clinically beneficial, one-third of patients retain suboptimal FFR after the procedure, associated with severe adverse events, rendering PCI in diffuse coronary artery disease questionable. Using the pullback pressure gradient (PPG), we can analyze the magnitude and extent of pressure losses; a lower value may indicate diffuse disease, while a high value with an abrupt curve may indicate focal disease. Since PCI is not the best option for treating diffuse coronary disease, current strategies focus on conservatively using medical therapy or bypass surgery. It has been demonstrated that patients with diffuse disease of the left anterior descending (LAD) are at a greater risk of developing occlusion of the left internal mammary artery graft than those with focal disease and that maximal medical therapy may be the most effective treatment for these patients.

Use of dual-lumen microcatheter pullback injection in complex percutaneous coronary intervention.

Dual-lumen microcatheters (DLMC) are utilized in challenging wiring scenarios as well as for contrast and medication injections. Nonetheless, lesion characterization remains extremely challenging in many cases. We describe a DLMC-facilitated technique which can assist in locating the distal anastomosis while navigating an occluded bypass graft during retrograde chronic total occlusion recanalization, as well as in the differential diagnosis of abrupt vessel closure. This "DLMC Pullback Injection" technique is performed by injecting contrast through the over-the-wire port of the DLMC, while the latter is quickly pulled back across the region of interest in a dynamic fashion. We believe this technique has the potential to solve challenging scenarios and to enrich the complex percutaneous coronary intervention operator's armamentarium.

Angiography-derived physiological assessment after percutaneous coronary intervention of chronic total occlusions.

Scant data exploring potential suboptimal physiological results after angiographic successful percutaneous coronary intervention (PCI) of chronic total occlusion (CTO) are available. Sixty cases of successful CTO-PCI were selected for this retrospective analysis. Post-CTO-PCI angiography-based fractional flow reserve was computed using the Murray-based fractional flow reserve (µFR) software. Vessel-specific µFR, residual trans-stent gradient (TSG) and corrected TSGstent were calculated. In physiological suboptimal results (µFR < 0.90), the virtual pullback pressure gradient (PPG) curves were analyzed to localize the main pressure drop-down and characterize the patterns of residual disease. The virtual pullback pressure gradient index (vPPGi) was then calculated to objectively characterize the predominant pattern of residual disease (diffuse vs focal). The physiological result was suboptimal in 28 cases (46.7%). The main pressure drop was localised proximal to the stent in 2 (7.1%), distal in 17 (60.7%) and intra-stent in 9 cases (32.2%). Intra-stent residual disease was diffuse in 7 cases and mixed in 2. Distal residual disease was characterised by a pure focal pattern in 12 cases, diffuse in 2 and mixed in 3. In the predominant diffuse phenotype (vPPGi < 0.65), we found a higher rate of TSG ≥ 0.04 (61.5% vs 20.0%, p = 0.025) and TSGstent ≥ 0.009 (46.2% vs 20.0%, p = 0.017) while in the dominant focal phenotype poor-quality distal vessel was constantly present. In our cohort, post-CTO-PCI suboptimal physiological result was frequent (46.7%). Predominant focal phenotype was constantly associated with poor-quality distal vessel, while in the predominant diffuse phenotype, the rate of TSG ≥ 0.04 and TSGstent ≥ 0.009 were significantly higher.

Intravascular Imaging Findings After PCI in Patients With Focal and Diffuse Coronary Artery Disease.

BACKGROUND: Following percutaneous coronary intervention (PCI), optical coherence tomography provides prognosis information. The pullback pressure gradient is a novel index that discriminates focal from diffuse coronary artery disease based on fractional flow reserve pullbacks. We sought to investigate the association between coronary artery disease patterns, defined by coronary physiology, and optical coherence tomography after stent implantation in stable patients undergoing PCI. METHODS AND RESULTS: This multicenter, prospective, single-arm study was conducted in 5 countries (NCT03782688). Subjects underwent motorized fractional flow reserve pullbacks evaluation followed by optical coherence tomography-guided PCI. Post-PCI optical coherence tomography minimum stent area, stent expansion, and the presence of suboptimal findings such as incomplete stent apposition, stent edge dissection, and irregular tissue protrusion were compared between patients with focal versus diffuse disease. Overall, 102 patients (105 vessels) were included. Fractional flow reserve before PCI was 0.65±0.14, pullback pressure gradient was 0.66±0.14, and post-PCI fractional flow reserve was 0.88±0.06. The mean minimum stent area was 5.69±1.99 mm2 and was significantly larger in vessels with focal disease (6.18±2.12 mm2 versus 5.19±1.72 mm2, P=0.01). After PCI, incomplete stent apposition, stent edge dissection, and irregular tissue protrusion were observed in 27.6%, 10.5%, and 51.4% of the cases, respectively. Vessels with focal disease at baseline had a lower prevalence of incomplete stent apposition (11.3% versus 44.2%, P=0.002) and more irregular tissue protrusion (69.8% versus 32.7%, P<0.001). CONCLUSIONS: Baseline coronary pathophysiological patterns are associated with suboptimal imaging findings after PCI. Patients with focal disease had larger minimum stent area and a higher incidence of tissue protrusion, whereas stent malapposition was more frequent in patients with diffuse disease.

Has the Integrated Medical Insurance System promoted return-to-hometown entrepreneurship among migrant workers? Evidence from China.

An important way to reduce urban-rural disparity lies in encouraging migrant workers to return to their hometowns for entrepreneurship. This paper examines the effect of the Integrated Medical Insurance System on the return-to-hometown entrepreneurship among migrant workers. Using microdata from the China Household Finance Survey (CHFS) spanning from 2013 to 2019, we find that the Integrated Medical Insurance System (IMIS) significantly increases the likelihood of migrant workers returning to their hometowns for entrepreneurship by 0.44%. This result remains stable after a series of robustness checks. Heterogeneity results indicate that this "pullback effect" is more pronounced for those who are male and with lower educational levels, higher income, larger social networks, and lower risk preferences. Finally, the interaction between the Mass Entrepreneurship and Innovation policy (MEI) and IMIS can create a more significant combined effect in promoting the return of migrant workers to their hometowns for entrepreneurial activities.

Geographic disparity of pathophysiological coronary artery disease characteristics: Insights from ASET trials.

BACKGROUND: The geographical disparity in the pathophysiological pattern of coronary artery disease (CAD) among patients undergoing percutaneous coronary intervention (PCI) is unknown. OBJECTIVES: To elucidate the geographical variance in the pathophysiological characteristics of CAD. METHODS: Physiological indices derived from angiography-based fractional flow reserve pullbacks from patients with chronic coronary syndrome enrolled in the ASET Japan (n = 206) and ASET Brazil (n = 201) studies, which shared the same eligibility criteria, were analysed. The pathophysiological patterns of CAD were characterised using Murray law-based quantitative flow ratio (µQFR)-derived indices acquired from pre-PCI angiograms. The diffuseness of CAD was defined by the µQFR pullback pressure gradient index. RESULTS: Significant functional stenoses pre-PCI (µQFR ≤0.80) were more frequent in ASET Japan compared to ASET Brazil (89.9% vs. 67.5%, p < 0.001), as were rates of a post-PCI µQFR <0.91 (22.1% vs. 12.9%, p = 0.013). In the multivariable analysis, pre-procedural µQFR and diffuse disease were independent factors for predicting a post-PCI µQFR <0.91, which contributed to the different rates of post-PCI µQFR ≥0.91 between the studies. Among vessels with a post-PCI µQFR <0.91, a consistent diffuse pattern of CAD pre- and post-PCI occurred in 78.3% and 76.7% of patients in ASET Japan and Brazil, respectively; only 6.3% (Japan) and 10.0% (Brazil) of vessels had a major residual gradient. Independent risk factors for diffuse disease were diabetes mellitus in ASET Japan, and age and male gender in Brazil. CONCLUSIONS: There was geographic disparity in pre-procedural angiography-based pathophysiological characteristics. The combined pre-procedural physiological assessment of vessel µQFR and diffuseness of CAD may potentially identify patients who will benefit most from PCI.

Influence of intracoronary hemodynamic forces on atherosclerotic plaque phenotypes.

BACKGROUND AND AIMS: Coronary hemodynamics impact coronary plaque progression and destabilization. The aim of the present study was to establish the association between focal vs. diffuse intracoronary pressure gradients and wall shear stress (WSS) patterns with atherosclerotic plaque composition. METHODS: Prospective, international, single-arm study of patients with chronic coronary syndromes and hemodynamic significant lesions (fractional flow reserve [FFR] ≤ 0.80). Motorized FFR pullback pressure gradient (PPG), optical coherence tomography (OCT), and time-average WSS (TAWSS) and topological shear variation index (TSVI) derived from three-dimensional angiography were obtained. RESULTS: One hundred five vessels (median FFR 0.70 [Interquartile range (IQR) 0.56-0.77]) had combined PPG and WSS analyses. TSVI was correlated with PPG (r = 0.47, [95% Confidence Interval (95% CI) 0.30-0.65], p < 0.001). Vessels with a focal CAD (PPG above the median value of 0.67) had significantly higher TAWSS (14.8 [IQR 8.6-24.3] vs. 7.03 [4.8-11.7] Pa, p < 0.001) and TSVI (163.9 [117.6-249.2] vs. 76.8 [23.1-140.9] m-1, p < 0.001). In the 51 vessels with baseline OCT, TSVI was associated with plaque rupture (OR 1.01 [1.00-1.02], p = 0.024), PPG with the extension of lipids (OR 7.78 [6.19-9.77], p = 0.003), with the presence of thin-cap fibroatheroma (OR 2.85 [1.11-7.83], p = 0.024) and plaque rupture (OR 4.94 [1.82 to 13.47], p = 0.002). CONCLUSIONS: Focal and diffuse coronary artery disease, defined using coronary physiology, are associated with differential WSS profiles. Pullback pressure gradients and WSS profiles are associated with atherosclerotic plaque phenotypes. Focal disease (as identified by high PPG) and high TSVI are associated with high-risk plaque features. CLINICAL TRIAL REGISTRATION: https://clinicaltrials,gov/ct2/show/NCT03782688.

An Unusual Hemodynamic Pressure Trace Mimicking Aortic Stenosis: A Decepti "Con".

We report an abnormal hemodynamic pressure tracing taken during pullback from the left ventricle. This report emphasizes the careful observation of hemodynamic tracing relative to continuous electrocardiographic monitoring for identifying potentially pathological vascular phenomena that may have detrimental outcomes on the clinical management of the underlying condition.