Coronary Slow Flow Phenomenon Research Articles

Analysis of correlative factors of female coronary slow-flow phenomenon: A retrospective study.

The coronary slow-flow phenomenon (CSFP) is a manifestation of coronary artery disease wherein coronary angiography reveals no apparent stenosis; however, there is a delay in blood flow perfusion. Given its increased occurrence in male patients, with the majority of subjects in previous studies being male, this study aimed to explore whether distinct risk factors are present in female patients with CSFP. This single-center retrospective study focused on female patients diagnosed with CSFP by using coronary angiography. Eligible patients meeting the predefined inclusion and exclusion criteria were divided into the study group (presenting with CSFP) and control group (displaying normal epicardial coronary arteries). Comparative analyses of clinical and diagnostic data were performed. Ninety-two patients with CSFP and an equal number of controls were enrolled in this study. Patients with CSFP exhibited a higher prevalence of smokers (P = .017) and a heightened incidence of diabetes mellitus (DM) (P = .007). Significantly elevated levels of total cholesterol (TC) (P = .034) and free fatty acids (FFA) (P = .016) were observed in the CSFP group compared to those in the control group. Additionally, patients with CSFP displayed lower levels of apolipoprotein E (ApoE) (P = .092), free thyroxine (FT4) (P = .001), and total thyroxine (TT4) (P = .025). Logistic regression analysis indicated that smoking (P = .019), FFA (P < .001), ApoE (P = .015), and FT4 (P < .001) were independent risk factors for CSFP, accounting for confounding factors. Additionally, the area under the ROC curve (AUC) of the combined effect of smoking, ApoE, FT4, and FFA on CSFP was 0.793 (95% CI: 0.729-0.857, P < .01). In addition to the established risk factors for smoking, diabetes, and hyperlipidemia, female patients with CSFP exhibited significant differences in apoE, FFA, FT4, and TT4 levels compared to the control group. Smoking, FFA, and FT4 levels emerged as independent risk factors for CSFP.

Epicardial fat volume is associated with primary coronary slow-flow phenomenon in patients with severe aortic stenosis undergoing transcatheter valve implantation

BackgroundPrimary coronary slow flow (CSF) is defined as delayed opacification of the distal epicardial vasculature during coronary angiography in the absence of relevant coronary artery stenoses. Microvascular disease is thought to be the underlying cause of this pathology. Epicardial fat tissue (EFT) is an active endocrine organ directly surrounding the coronary arteries that provides pro-inflammatory factors to the adjacent tissue by paracrine and vasocrine mechanisms. The aim of the present study was to investigate a potential association between EFT and primary CSF and whether EFT can predict the presence of primary CSF.MethodsBetween 2016 and 2017, n = 88 patients with high-grade aortic stenosis who were planned for transcatheter aortic valve implantation (TAVI) were included in this retrospective study. EFT volume was measured by pre-TAVI computed tomography (CT) using dedicated software. The presence of primary CSF was defined based on the TIMI frame count from the pre-TAVI coronary angiograms.ResultsThirty-nine of 88 TAVI patients had CSF (44.3%). EFT volume was markedly higher in patients with CSF (142 ml [IQR 107–180] vs. 113 ml [IQR 89–147]; p = 0.009) and was strongly associated with the presence of CSF (OR 1.012 [95%CI 1.002–1.021]; p = 0.014). After adjustment, EFT volume was still an independent predictor of CSF (OR 1.016 [95%CI 1.004–1.026]; p = 0.009).ConclusionPrimary CSF was independently associated with increased EFT volume. Further studies are needed to validate this finding and elucidate whether a causal relationship exists.

Effect of nano-curcumin supplementation on angina status, and traditional and novel cardiovascular risk factors in overweight or obese patients with coronary slow flow phenomenon: a randomized double-blind placebo-controlled clinical trial

BackgroundCardiovascular events and poor quality of life are frequently observed in patients with coronary slow flow phenomenon (CSFP). This trial evaluated the effect of nano-curcumin supplement containing curcuminoids, as multifunctional nutraceuticals, on angina status, and some traditional and novel cardiovascular risk factors in overweight or obese patients with CSFP.MethodsIn this double-blind, randomized, placebo-controlled clinical trial, 42 overweight or obese patients with CSFP received either 80 mg/day of nano-curcumin or placebo for 12 weeks. Seattle angina questionnaire (SAQ) as a clinical measure of angina status, circulating endocan, adropin, homocysteine, lipid profile, and the novel scores of visceral adiposity index (VAI) and waist-triglyceride index (WTI) were assessed before and after the intervention. The independent samples t-test, Mann-Whitney test, analysis of covariance, Chi-square, and Fisher’s exact tests were used where appropriate.ResultsAll domains of SAQ including physical limitation, angina stability, angina frequency-severity, treatment satisfaction, and disease perception and quality of life improved significantly in the nano-curcumin compared with the placebo group. No significant changes were observed in serum endocan, adropin, and homocysteine following the intervention. Triglycerides, triglyceride/high-density lipoprotein cholesterol ratio, WTI and VAI values improved significantly only within the nano-curcumin group.ConclusionsSupplementation with 80 mg/day nano-curcumin (containing curcuminoids) for 12 weeks significantly improved clinically important disease-specific aspects of health in patients with CSFP. Some traditional and novel cardiovascular risk factors improved significantly only compared with the baseline values, which need further investigation.Trial registrationThis study was approved by the Ethics Committee of Tehran University of Medical Sciences (IR.TUMS.VCR.REC.1398.794). The study protocol was registered at Iranian Registry of Clinical Trials by IRCT20131125015536N8 registration ID at 19.06.2019.

Could Pan-Immune-Inflammation Value be a Marker for the Diagnosis of Coronary Slow Flow Phenomenon?

Inflammation plays a key role in the pathogenesis of the coronary slow flow phenomenon (CSFP). The newly developed inflammatory marker, pan-immune-inflammation value (PIV), is associated with adverse cardiovascular events. This study investigated the predictive value of PIV for diagnosing CSFP in comparison to other inflammation-based markers. A total of 214 patients, 109 in the CSFP group and 105 in the normal coronary flow (NCF) group, were retrospectively included in the study. Coronary flow was calculated using the Thrombolysis in Myocardial Infarction frame count method. In addition to PIV, other inflammatory markers such as neutrophil-lymphocyte ratio, platelet-lymphocyte ratio (PLR), and systemic immune-inflammation index (SII) were calculated for the patients. The average age of patients was 50.3 ± 8.4, with a male ratio of 55.1%. Compared to the NCF group, patients in the CSFP group had higher levels of hyperlipidemia, glucose, triglyceride, NLR, PLR, SII, and PIV, while their high-density lipoprotein cholesterol (HDL-C), was lower (p < 0.05). Logistic regression analysis demonstrated that HDL-C, glucose, triglyceride, and PIV were independent predictor factors for CSFP (p < 0.05). PIV is a strong and independent predictor factor for CSFP and superior in predicting CSFP compared to other inflammatory markers.

The triglyceride-glucose index as a predictive marker for coronary slow flow phenomenon.

The triglyceride-glucose index (TyG) has been proposed as a marker of insulin resistance (IR) and has shown associations with cardiovascular diseases. This study aimed to investigate the relationship between the TyG and the coronary slow flow phenomenon (CSFP) and explore the index's potential as a predictor of this condition. A total of 187 patients who underwent coronary angiography were included; of these, 91 patients were diagnosed with CSFP, and 96 patients with normal coronary flow served as a control group. The TyG was calculated using fasting triglyceride and glucose levels. The results showed that the TyG was significantly higher in the CSFP group compared with the control group (p < 0.001). Additionally, the TyG exhibited a moderate positive correlation with the thrombolysis-in-myocardial-infarction frame count in coronary arteries (p < 0.001). A multivariate logistic regression analysis revealed that the TyG, along with gender, ejection fraction, and uric acid, remained significant predictors of CSFP (p < 0.05). This study's findings suggest that the TyG may serve as a useful marker for identifying individuals at risk of CSFP and provide insights into the potential role of IR in its pathophysiology.

Analysis of Risk Factors and Construction of a Predictive Model for Readmission in Patients with Coronary Slow Flow Phenomenon.

Coronary slow flow phenomenon (CSFP) is a phenomenon in which distal vascular perfusion is delayed on angiography, but coronary arteries are not significantly narrowed and there is no other organic cardiac disease. Patients with CSFP may be repeatedly readmitted to the hospital because of chest pain or other symptoms of precordial discomfort, and there is a risk of adverse events. In order to investigate the risk factors affecting the readmission of CSFP patients, a prediction model was constructed with the aim of identifying patients at risk of readmission at an early stage and providing a reference for further clinical intervention. In this study, we collected clinical data from 397 CSFP patients between June 2021 and January 2023 in Xinjiang Medical University Hospital. Telephone follow-up clarified whether the patients were readmitted to the hospital. A predictive model for readmission of CSFP patients was constructed using multifactorial logistic regression. Nomogram was used to visualize the model and bootstrap was used to internally validate the model. ROC, DCA and Calibration curve were plotted to evaluate the calibration and discriminative ability of the column line graphs, respectively. Calibration and resolution of the column line graphs, respectively. A total of 34 of 397 CSFP patients experienced readmission. Smoking history, creatine kinase isoenzyme-MB, total cholesterol, and left ventricular ejection fraction were the predictors of readmission in patients with CSFP. The area under the curve of the Nomogram model was 0.87, which indicated that the model had good predictive ability and differentiation, and the DCA and Calibration curves also indicated that the model had good consistency and was clinically useful. A readmission prediction model for patients with CSFP may facilitate early identification of patients at potential risk for readmission and timely interventional therapy to improve patient prognosis.

The MAPH Score Predicts Coronary Slow Flow. A Retrospective Case-Controlled Study.

The MAPH score is a new score that combines mean platelet volume (MPV), hematocrit, and total protein, which are markers of whole blood viscosity (WBV). We aimed to investigate the relationship between the MAPH score and the coronary slow flow phenomenon (CSF). A total of 201 patients were included in the study. 105 had CSF and 96 had normal coronary flow (NCF). Coronary flow was measured by the Thrombolysis in Myocardial Infarction frame count (TFC) method. The patients' MPV, age, hematocrit, and total protein were recorded. High (HSR) and low shear rates (LSR) were calculated, based on total protein and hematocrit values. Cut-off values for CSF were determined using the Youden's index, and the score was determined as 0 or 1 according to the cut-off values. The sum of these scores was the MAPH score. The mean age of the patients included in the study was 51.1±7.9 (n=201, 54.2 % male). Hyperlipidemia, DM, and HT rates of both groups were similar, but the mean age of the CSF group was higher (p=0.773; p=0.549; p=0.848; p &lt;0.001, respectively). Total protein, MPV, hematocrit, HSR and LSR were higher in the CSF group (p&lt; 0.001, for all values). Comparative receiver operating characteristic (ROC) curve analysis showed that the performance of the MAPH score in predicting CSF is better than the performance of these parameters separately. A new score, the MAPH score, may be used to identify the presence of CSF.

Anti-Anginal Efficacy of Zibotentan in the Coronary Slow-Flow Phenomenon.

Patients with coronary microvascular disorders often experience recurrent angina for which there are limited evidence-based therapies. These patients have been found to exhibit increased plasma levels of endothelin; thus, selective endothelin-A (Et-A) receptor blockers such as zibotentan may be an effective anti-anginal therapy in these patients. The study evaluated the impact of a 10 mg daily dose of zibotentan on spontaneous angina episodes in patients with the coronary slow-flow phenomenon who had refractory angina (i.e., experiencing angina at least three times/week despite current anti-anginal therapy). Using a randomized, double-blind, placebo-controlled, crossover trial design with 4-week treatment periods, 18 patients (63.2 ± 9.9 years, 33% females) were recruited. The primary endpoint was angina frequency as measured by an angina diary, with secondary endpoints including nitrate consumption, angina duration/severity and the Seattle Angina Questionnaire (SAQ) domains. During the 4 weeks of therapy, angina frequency significantly improved with zibotentan therapy (placebo 41.4 (58.5) vs. zibotentan 29.2 (31.6), p < 0.05), and sublingual nitrate consumption significantly reduced (placebo 11.8 (15.2) vs. zibotentan 8.8 (12.9), p < 0.05. Zibotentan improved the frequency of spontaneous angina episodes and reduced sublingual nitrate consumption in patients unresponsive to standard anti-anginal therapy.

Coronary Slow-Flow Phenomenon in Takotsubo Syndrome: The Prevalence, Clinical Determinants, and Long-Term Prognostic Impact.

Patients with takotsubo syndrome (TTS) may present coronary slow flow (CSF) in angiography performed in the acute myocardial infarction (MI). However, the detailed clinical relevance and its long-term impact remain poorly understood. Among 7771 MI patients hospitalized between 2012 and 2019, TTS was identified in 82 (1.1%) subjects. The epicardial blood flow was assessed with thrombolysis in myocardial infarction (TIMI) scale and corrected TIMI frame count (TFC), whereas myocardial perfusion with TIMI myocardial perfusion grade (TMPG). CSF was defined as TIMI-2 or corrected TFC > 27 frames in at least one epicardial vessel. CSF was identified in 33 (40.2%) TTS patients. In the CSF-TTS versus normal-flow-TTS group, lower values of left ventricular ejection fraction on admission (33.5 (25-40) vs. 40 (35-45)%, p = 0.019), more frequent midventricular TTS (27.3 vs. 8.2%, p = 0.020) and the coexistence of both physical and emotional triggers (9.1 vs. 0%, p = 0.032) were noted. Within a median observation of 55 months, higher all-cause mortality was found in CSF-TTS compared with normal-flow TTS (30.3 vs. 10.2%, p = 0.024). CSF was identified as an independent predictor of long-term mortality (hazard ratio 10.09, 95% confidence interval 2.12-48.00, p = 0.004). CSF identified in two-fifths of TTS patients was associated with unfavorable long-term outcomes.

Triglyceride glucose-body mass index as a novel predictor of slow coronary flow phenomenon in patients with ischemia and nonobstructive coronary arteries (INOCA)

BackgroundThe triglyceride glucose-body mass index (TyG-BMI index) has been suggested as a novel predictor of insulin resistance. However, its predictive value for slow coronary flow phenomenon (SCFP) in patients with ischemia and nonobstructive coronary arteries (INOCA) remains unclear.MethodsWe consecutively recruited 1625 patients with INOCA from February 2019 to February 2023 and divided them into two groups based on thrombolysis in myocardial infarction (TIMI) frame counts (TFCs): the SCFP group (n = 79) and the control group. A 1:2 age-matched case–control study was then performed. The TyG-BMI index was calculated as ln [plasma triglyceride (mg/dL) × fasting blood glucose (mg/dL)/2] × BMI.ResultsTyG-BMI index in the SCFP group (218.3 ± 25.2 vs 201.0 ± 26.5, P < .001) was significantly higher than in the normal controls. TyG-BMI index also increased with the number of coronary arteries involved in the SCFP. Multivariate logistic regression analysis showed that TyG-BMI, BMI, and TG were independent predictors for SCFP. Receiver operating characteristic (ROC) curve analysis showed that when the TyG-BMI index was above 206.7, the sensitivity and specificity were 88.6% and 68.5%, respectively, with an AUC of 0.809 (95% CI: 0.756–0.863, P = .027). Combined BMI with TG, the TyG-BMI index had a better predictive value for SCFP than BMI and TG (P < .001).ConclusionThe TyG-BMI index was an independent predictor for SCFP in INOCA patients, and it had a better predictive value than BMI and TG.

The Impact of Coronary Slow Flow Phenomenon on Diastolic Function Trajectory in Patients with Non-ST Segment Elevation Acute Coronary Syndrome

The Impact of Coronary Slow Flow Phenomenon on Diastolic Function Trajectory in Patients with Non-ST Segment Elevation Acute Coronary Syndrome

Evaluation of serum nitric oxide synthase levels in patients with coronary slow flow based on corrected TIMI frame count.

The coronary slow flow phenomenon (CSFP) finding in angiography is characterized by the delayed filling of the terminal vessels without significant epicardial coronary disease. The endothelium performs a vital role in cardiovascular homeostasis by releasing vasoactive substances. Endothelial cells produce nitric oxide (NO) as one of these essential compounds. Three isoforms of nitric oxide synthase (NOS) are endothelial nitric oxide synthase (eNOS), neuronal nitric oxide synthase (nNOS), and induced nitric oxide synthase (iNOS). We aimed to determine the role of NOS in the development of CSFP as the first human study. A total of 129 patients who met the inclusion criteria were enrolled in the study. The patients were classified into five groups based on the results of coronary angiography: Group 1 without coronary artery disease (CAD) and without CSF, group 2 without CAD and with CSF, group 3 with CAD (< 50%) and without CSF, group 4 with CAD (50-90%) and without CSF, and group 5 with CAD and CSF. The serum level of NOS was determined in the participants. Coronary flow was quantified in patients with CSFP using the corrected TIMI frame count (CTFC) method, and the correlation between the levels of this biomarker and CTFC was investigated. In this study, the NOS serum levels were not significantly correlated with the mean CTFC. Since the total amount of NOS was measured as a result of 3 isoforms of this enzyme, the lack of correlation could be related to increased iNOS level and decreased eNOS concentration. These results should be confirmed by more human studies.

Diagnostic Indicators of ECG for Coronary Slow Flow Phenomenon; a Systematic Review and Meta-Analysis.

Currently, epicardial coronary angiography is still the only diagnostic tool for Coronary Slow Flow Phenomenon (CSFP). This study aimed to systematically review studies that compared Electrocardiogram (ECG) findings between patients with and without CSFP. Using relevant key terms, we systematically searched MEDLINE, Scopus, Embase, and Web of Science to find relevant studies up to February 5th, 2023. Effect sizes in each study were calculated as mean differences and crude odds ratio; then, random-effect models using inverse variance and Mantel-Haenszel methods were used to pool standardized mean differences (SMD) and crude odds ratios, respectively. Thirty-two eligible articles with a total sample size of 3,937 patients (2,069 with CSFP) were included. CSFP patients had higher P-wave maximum (Pmax) (SMD: 1.02 (95% confidence interval (CI): 0.29 - 1.76); p=0.006) and P-dispersion (Pd) (SMD: 1.63 (95% CI: 0.99 - 2.27); p<0.001) compared to the control group. CSFP group also showed significantly longer QT wave maximum duration (SMD: 0.69 (95% CI: 0.33 - 1.06); p<0.001), uncorrected QTd (SMD: 1.89(95% CI: 0.67 - 3.11); p=0.002), and corrected dispersion (QTcd) (SMD: 1.63 (95% CI: 1.09 - 2.17), p<0.001). The frontal QRS-T angle was significantly higher in the CSFP group in comparison with the control group (SMD: 1.18 (95% CI: 0.31 - 2.04; p=0.007). While CSFP patients had a significantly higher T-peak to T-end (Tp-e) (SMD:1.71 (95% CI: 0.91, 2.52), p<0.001), no significant difference was noted between groups in terms of Tp-e to QT (p=0.16) and corrected QT ratios (p=0.07). Our findings suggest several ECG parameters, such as P max, Pd, QT, QTc, QTd, QTcd, Tp-e, and frontal QRS-T angle, may be prolonged in CSFP patients, and they could be employed as diagnostic indicators of CSFP before angiography.

Association between pan-immune-inflammation value and coronary slow flow phenomenon in patients with angiographically normal coronary arteries

IntroductionCoronary slow flow phenomenon (CSFP) is characterized by the delayed contrast filling of terminal vessels of coronary arteries in the presence of normal or nearly normal epicardial coronary arteries. Given that inflammation plays a role in cardiovascular disorders, including CSFP, using peripheral blood-derived compound prognostic indexes could be a feasible way to predict the presence of CSFP. Therefore, in the present study, we evaluated the association between pan-immune-inflammation value (PIV) and the CSFP. MethodsThis single-center, retrospective study was composed of 612 patients aged over 18 years who underwent CAG for suspected stable ischemic heart disease. The association of clinical and laboratory parameters with the CSFP was evaluated with univariate and multivariate analyses. ResultsThe median age of the patients was 54 (IQR 46–63) and 61.3% of the patients were male. The 12.6% (84/612) of the patients had CSFP, while the coronary flow was normal in the remaining 87.4% of patients. The PIV levels had moderate success for the prediction of the CSFP (AUC: 0.675, 95% CI: 0.615–0.735, p < 0.001). In multivariate analyses, male gender (OR: 4.858, 95% CI: 2.851–8.277, p < 0.001), presence of diabetes (OR: 2.672, 95% CI: 1.396–5.113, p = 0.003), lower HDL-C values (OR: 2.120, 95% CI: 1.286–3.496, p = 0.003), and higher PIV levels (OR: 2.527, 95% CI: 1.519–4.203, p < 0.001) were associated with a higher risk of CSFP. ConclusionWe demonstrated that a higher risk of CSFP in patients with PIV levels. If supported by prospective evidence, PIV levels could be used as a minimally invasive reflector of CSFP.

Assessment of the relationship between plasma fibrinogen-to-albumin ratio and slow coronary flow phenomenon in patients without obstructive coronary artery disease

BackgroundPrior studies have suggested that the chronic inflammatory response has an important role in the pathophysiology of slow coronary flow phenomenon (SCFP). However, data are scarce regarding the role of plasma fibrinogen-to-albumin ratio (PFAR) in patients having SCFP without obstructive coronary artery disease (CAD). In this study, we investigated the relationship between PFAR and the presence of SCFP in patients without obstructive CAD.MethodsFrom January 2021 to January 2023, we consecutively recruited 1085 patients without obstructive CAD according to the diagnostic and exclusion criteria. In total, SCFP was diagnosed in 70 patients. A 1:2 age-matched case–control study was then conducted using comparators without SCFP. Ultimately, this study enrolled 70 patients with angiographically normal coronary arteries and SCFP, along with 140 comparators with angiographically normal coronary arteries and normal coronary flow. Plasma fibrinogen and albumin levels were measured, and the PFAR was then calculated for each patient.ResultsPFARs were significantly greater in the SCFP group than in the comparators with normal coronary flow (82.8 ± 15.4 vs 73.1 ± 19.5, p < 0.001). PFAR increased with increasing numbers of vessels affected by SCFP. Multivariate logistic regression analysis showed that PFAR was an independent predictor of SCFP (odds ratio: 1.818, p = 0.015). Receiver operating characteristic (ROC) curve analysis indicated that PFAR showed a better predictive value of SCFP than fibrinogen or albumin, although not significantly (p > 0.05).ConclusionPFAR is an independent predictor of SCFP in patients without obstructive CAD. PAFR could improve the predictive value of SFCP than albumin or fibrinogen alone, but not significantly.

The Anti-Anginal Efficacy of Bosentan in the Coronary Slow Flow Phenomenon

Background: The Coronary Slow Flow Phenomenon (CSFP) is a coronary microvascular disorder that presents with recurrent angina for which there is no available effective therapy. The vasoconstrictor Endothelin-1 (ET-1) has been implicated in the pathophysiology of the CSFP. This study aimed to determine whether the ET-1 antagonist (Bosentan) is effective in ameliorating angina symptoms in CSFP patients. Methods: Using a randomised, double-blind, placebo-controlled, cross-over trial methodology, the anti-anginal efficacy of Bosentan 125mg bd was assessed in 23 patients with symptomatic CSFP. Study endpoints were measured following 4 weeks of therapy with the primary endpoint being angina frequency. Secondary endpoints included (1) clinical measures of angina and health status, (2) endothelial function parameters, and (3) inflammatory and oxidative stress markers. Results: There was no statistically significant reduction in angina frequency with Bosentan therapy compared to placebo (median angina episodes/4weeks [25-75% IQ]: Bosentan 14[5,36] vs Placebo 25[9,55]) although a trend for improvement in symptoms during the Bosentan phase was observed. Furthermore, Bosentan did not impact on any of the secondary endpoints compared with placebo. Conclusion: Bosentan did not have a major impact on angina frequency in patients with the CSFP. A small anti-anginal effect cannot be excluded and requires a larger trial.

The Anti-Anginal Efficacy of Bosentan in the Coronary Slow Flow Phenomenon

Background: The Coronary Slow Flow Phenomenon (CSFP) is a coronary microvascular disorder that presents with recurrent angina for which there is no available effective therapy. The vasoconstrictor Endothelin-1 (ET-1) has been implicated in the pathophysiology of the CSFP. This study aimed to determine whether the ET-1 antagonist (Bosentan) is effective in ameliorating angina symptoms in CSFP patients. Methods: Using a randomised, double-blind, placebo-controlled, cross-over trial methodology, the anti-anginal efficacy of Bosentan 125mg bd was assessed in 23 patients with symptomatic CSFP. Study endpoints were measured following 4 weeks of therapy with the primary endpoint being angina frequency. Secondary endpoints included (1) clinical measures of angina and health status, (2) endothelial function parameters, and (3) inflammatory and oxidative stress markers. Results: There was no statistically significant reduction in angina frequency with Bosentan therapy compared to placebo (median angina episodes/4weeks [25-75% IQ]: Bosentan 14[5,36] vs Placebo 25[9,55]) although a trend for improvement in symptoms during the Bosentan phase was observed. Furthermore, Bosentan did not impact on any of the secondary endpoints compared with placebo. Conclusion: Bosentan did not have a major impact on angina frequency in patients with the CSFP. A small anti-anginal effect cannot be excluded and requires a larger trial.

Changes of left atrial morphology and function evaluated with four-dimensional automated left atrial quantification echocardiography in patients with coronary slow flow phenomenon and preserved left ventricular ejection fraction

BackgroundCoronary slow flow phenomenon (CSFP) can cause left ventricular diastolic dysfunction (LVDD). In multiple studies, the left atrial (LA) strain has been reported to be an excellent parameter for assessing LVDD. The 4-dimensional automated LA quantification (4D Auto LAQ) dedicated to the LA was recently available. Our study aimed to evaluate subclinical changes in LA morphology and function with 4D Auto LAQ in patients with CSFP and preserved left ventricular ejection fraction (LVEF). MethodsForty-eight patients with CSFP confirmed with coronary angiography and 46 age and gender-matched controls with normal coronary flow were enrolled. The thrombolysis in myocardial infarction frame count (TFC) method was used to record coronary blood flow velocities for each major coronary artery. LA volume, LA longitudinal and circumferential strains during each of the three LA phases (reservoir, conduit, and contraction), LA total emptying fraction (LATEF), LA active emptying fraction (LAAEF), and LA passive emptying fraction (LAPEF) were quantified with 4D Auto LAQ analysis. ResultsCompared with controls, LA longitudinal reservoir strain (LASr), LA longitudinal strain during the conduit phase (LAScd), LA contraction strain (LASct), LA conduit circumferential strain (LAScd-c), LATEF, LAPEF decreased significantly in individuals with CSFP. Of the 4D- LAQ parameters, only LASr [odds ratio (OR): 0.773, P < 0.001] and LATEF [OR: 0.762, P < 0.001] were associated with CSFP in multivariate analysis. A LASr ≤23.00% can differentiate CSFP from controls [sensitivity, 66.7%; specificity, 93.5%; area under the curve (AUC), 0.823; P < 0.001]. A LASr of ≤19.00% could predict the elevation of LV filling pressure in the CSFP cohort [sensitivity, 76.9%; specificity, 74.3%; area under the curve (AUC), 0.792; P < 0.001]. LASr was the only index to demonstrate significant changes compared to controls in single-vessel CSFP. Compared to the right coronary artery (RCA) and left circumflex (LCX), TFC of the left anterior descending (LAD) artery was the only independent variable of LASr (Standardized Coefficients: -0.386, P = 0.037). ConclusionsImpairment of LA reservoir function reflected by changes in LASr and LATEF can be seen in patients with CSFP. LASr could predict the elevation of LV filling pressure in CSFP individuals. LASr is more sensitive than LATEF in detecting LA reservoir dysfunction in single-vessel CSFP. CSFP in LAD exerts a more prominent influence on LASr than RCA or LCX.

The expression levels of PPAR-α/γ and UCP1/2 on the slow coronary flow phenomenon; results from a case-control study.

The slow coronary flow (SCF) phenomenon is considered a coronary artery disorder. Because of the critical function of peroxisome proliferator-activated receptors (PPARs) in regulating the oxidative stress and inflammatory reactions in cardiovascular disease, The aim of the current study was to investigate the expression of the genes for uncoupling proteins 1 and 2 (UCP1 and UCP2), peroxisome proliferator-activated receptors and (PPAR- PPAR-), and PPAR- in SCF patients. In this case-control study, coronary angiography examination was used to analyze 35 individuals with SCF and 35 subjects with normal coronary flow (NCF). SCF was diagnosed using the TIMI (thrombolysis in myocardial infarction frame count) method. The SCF phenomenon is thought to be the TIMI > 27. In the peripheral blood mononuclear cells (PBMCs), the messenger ribonucleic acid (mRNA) expression levels of the PPAR-, PPAR-, UCP1, and UCP2 genes were evaluated. UCP1 and UCP2 expression levels were significantly higher in the SCF group compared to the NCF group (P = 0.034 and P0.001, respectively). The PPAR- and PPAR- levels were found to be significantly lower in the SCF group compared to the NCF group (P = 0.015, P0.001, respectively). According to the results of the logistic regression analysis, high UCP1 and UCP2 levels and low PPAR- and PPAR- levels are each independent predictors of the SCF phenomenon. This research provided evidence about the potential role of PPAR-α, PPAR-γ, UCP1, and UCP2 as biomarkers in SCF. More investigations are suggested to assess the functions of these factors in SCF patients mechanistically.

Homocysteine levels in patients with coronary slow flow phenomenon: A meta-analysis.

With the development of coronary angiography, more and more attention has been paid to coronary slow flow phenomenon (CSFP). Recent studies have found that the correlation between homocysteine (Hcy) levels and CSFP was contradictory, so we conducted this meta-analysis to investigate the correlation. By March 2022, studies that meet the research requirements were identified by searching multiple databases including Embase, Web of Science, and PubMed. We included studies evaluating the correlation between Hcy levels and CSFP. Random or fixed effect meta-analyses were performed according to heterogeneity among included studies. A leave-out method and subgroup analyses were conducted to determine the source of heterogeneity. Thirteen studies involving 625 CSFP and 550 subjects were included. After pooling data from each study, Hcy levels were higher in the CSFP groups (standard mean difference [SMD], 1.45; 95% CI, 0.94 to 1.96, P < .00001) than in the control group. In the meta-analysis, there was significant heterogeneity (I2 = 93%), which was further explored through leave-out method and and subgroup analyses. Specifically, pooling data from studies with a mean thrombolysis in myocardial infarction (TIMI) frame count ≥ 46 (SMD, 1.31; 95% CI, 1.00 to 1.63, P < .00001) resulted in no heterogeneity (0%), indicating that the TIMI frame count ≥ 46 was the source of heterogeneity. Our study found that elevated Hcy levels are strongly associated with CSFP. More importantly, the association was stronger in CSFP patients with mean TIMI frame count ≥ 46.