Effect of Coronary Slow Flow on the Longitudinal Left Ventricular Function Assessed by 2-Dimensional Speckle-Tracking Echocardiography

Evaluation of the relationship between clinical and laboratory risk factors in atherosclerosis patients with coronary slow flow: a case-control analysis

BACKGROUND

Coronary slow flow (CSF) is an angiographic entity distinguished by the delayed filling of the epicardial coronary arteries in the lack of significant obstructive artery disease. The pathological causes are still unknown. This study aimed to elucidate the relationship between clinical and laboratory-related risk factors in atherosclerosis patients diagnosed with CSF.

RESULTS

The research encompassed a study group of 142 individuals, with a mean age of 52.47 ± 10.62, and a male representation of 47.7%. A thorough statistical analysis was conducted, indicating that there were no noteworthy variations in age, gender, smoking history, hematocrit, blood sugar, and HDL levels between the groups of cases and controls (P > 0.05). Subsequent analysis of the data indicated that there were significant differences in history of hypertension, LDL, and BMI measurements between the groups of subjects who were designated as cases and those who were designated as controls. Our study revealed that male gender, a history of hypertension, and BMI were identified as independent predictors of CSF (P < 0.05).

CONCLUSIONS

After modeling regression, we were able to conclude that male gender, BMI, and history of hypertension are reliable predictors of slow coronary flow. These findings add to our growing understanding of the complex interplay between clinical and laboratory risk factors in the development and progression of CSF.

Evaluation of cardiac chamber functions by speckle-tracking echocardiography in the presence of coronary artery flow disturbances other than stenosis: A review

Conditions other than stenosis also disturb the coronary flow. Such conditions include the coronary slow flow phenomenon, coronary artery ectasia, and coronary artery tortuosity. Evidence exists regarding myocardial dysfunction in these conditions. In this review, we present studies that have used speckle-tracking echocardiography to determine whether coronary flow disturbances are accompanied by myocardial dysfunction. Additionally, we seek to show the gaps in knowledge concerning this issue and the dimensions that future studies should consider.

Incremental Value of Three-dimensional Speckle-tracking Echocardiography for Evaluating Left Ventricular Systolic Function in Patients with Coronary Slow Flow

The purpose was to evaluate left ventricular (LV) systolic function in patients with coronary slow flow (CSF), and compared the incremental values of 3-dimensional (3D) speckle-tracking echocardiography (STE). Seventy-three patients with CSF and 60 control subjects were enrolled. CSF was diagnosed during coronary angiography. Two-dimensional (2D) and 3D global strain were measured using STE. Sex, mitral E, 2D GLS, and all 3D strain parameters were independent predictors of CSF. Combination of sex, mitral E, and 3D GTS had the highest area under the curve (AUC) for identifying CSF (AUC, 0.81; P < 0.001). Integrated discrimination index (IDI) improved adding 3D GTS to the combined sex and mitral E model (IDI = 0.12, P = 0.01) or 2D GLS model (IDI = 0.14, P < 0.001). LV systolic function was impaired in CSF patients. 3D GTS had an independent and incremental value for predicting CSF compared with 2D echocardiography.

Echocardiographic and laboratory findings in coronary slow flow phenomenon: cross-sectional study and review

Background

Coronary sow-flow phenomenon (CSFP) is defined as slow passage of the contrast injected into the coronary arteries without distal obstruction of the vessel.

Methods

The present study was a cross-sectional, descriptive-analytical study performed at the Seyed-al-Shohada Heart Center during 2018–2019. The eligible patients based on the inclusion and exclusion criteria were divided into the study group showing the CSFP and the control group with normal epicardial coronary arteries.

Results

The study included 124 patients. 67.9% of the study group and 39.4% of the control group were male patients (p-value = 0.001), and the mean patient age was 52.18 ± 12.55 and 51.77 ± 10.36 years in the study and control groups, respectively (p-value = 0.18). The study group had a significantly higher BMI than the control group (p < 0.05) and also a higher prevalence of smoking and hypertension. The variables of ALC, Hct, Plt, MPV, RDW, Cr, triglyceride, TC, and LDL, were higher in the study group. Given the echocardiographic findings, the mean E wave was significantly lower in the study group, while the control group had a significantly higher GLS (p-value = 0.01). Also, left anterior descending artery was the most common artery involved with CSFP.

Conclusion

The CSFP was significantly more common in men, smokers, hypertensive patients, and patients with high BMI. Moreover, these patients had significantly higher platelet count, MPV, LDL, and FBS. Some other laboratory variables were also higher in these patients. Given the echocardiographic findings, mild diastolic dysfunction and low GLS were also observed in the study group.

Early Assessment of Left Ventricular Function by Layer-Specific Strain and Its Relationship to Pulsatile Arterial Load in Patients with Coronary Slow Flow

Previous studies reported a controversial left ventricular (LV) function impairment and pathophysiology in patients with coronary slow flow (CSF). Greater arterial load has been shown to increase aortic impedance and endothelial shear stress, potentially affecting coronary anatomy and function. We investigated LV systolic function by a new layer-specific strain technology and assessed the association between pulsatile arterial load and contractility.A total of 70 patients with CSF and 50 controls with normal coronary angiography were included in the study. Layer-specific longitudinal and circumferential strains were assessed from endocardium, mid-myocardium, and epicardium (global longitudinal strain (GLS)-endo, GLS-mid, GLS-epi and GCS-endo, GCS-mid, GCS-epi) by two-dimensional speckle tracking imaging (2D-STI). Pulsatile arterial load was estimated by indexed arterial compliance (ACI). Layer-specific GLS showed a decreasing gradient from the endocardium to the epicardium in both the controls and CSF group. GLS-endo and GLS-mid in the CSF group were significantly lower than the control group (all P < 0.05). Layer-specific longitudinal strain showed a good correlation with the number of affected coronary arteries (all P < 0.05) and the mean thrombolysis in the myocardial infarction frame count (TFC) (all P < 0.05). ACI was lower in patients with CSF (P = 0.005), and ACI was correlated negatively with layer-specific GLS (all P < 0.05).Layer-specific evaluation of the LV provides an understanding of the layer-specific properties of the LV wall and the possible process of the LV impairment in patients with CSF. Greater pulsatile arterial load, as manifested by a lower ACI, is coupled with worse LV longitudinal function in patients with CSF.

Evaluation of longitudinal left ventricular function in patients with coronary artery ectasia and vitamin D deficiency by 2D speckle tracking echocardiography

OBJECTIVES

Coronary artery ectasia (CAE) is defined as the dilation of at least one segment of the coronary arteries that reaches at least 1.5 times the size of a normal neighboring segment. It has been shown that left ventricular (LV) diastolic function is impaired in patients with CAE. Also, it has been shown that LV function is impaired in vitamin D-deficient subjects compared with vitamin D-sufficient subjects and vitamin D deficiency is prevalent in CAE patients. We hypothesized that LV function is impaired in patients with CAE so we evaluated longitudinal LV myocardial function by 2D speckle tracking echocardiography (2DSTE) in patients with CAE and vitamin D deficiency without significant coronary artery stenosis and compared the results with those of subjects with vitamin D deficiency and near-normal coronary arteries.

METHODS

Our study population comprised 21 consecutive patients with CAE and without significant coronary artery stenosis (<50%) and 31 control subjects with near-normal coronary arteries. All subjects had vitamin D deficiency.

RESULTS

All 2DSTE-derived indices of longitudinal LV function, comprised of the absolute values of systolic strain (14.0±2.7% vs 15.4±2.3%, P=.039), systolic strain rate (1.2±0.2/s vs 1.3±0.2/s, P=.015), early diastolic strain rate (1.1±0.3/s vs 1.3±0.3 s^-1 , P=.030), and late diastolic strain rate (0.8±0.2/s vs 1±0.2/s^, P=.005), were reduced in the patients with CAE and vitamin D deficiency.

CONCLUSIONS

The systolic and diastolic functions of the LV in the patients with CAE and vitamin D deficiency were impaired as evaluated by 2DSTE.

Is Left Atrial Function Affected by Coronary Slow Flow? A Two-dimensional Speckle-Tracking Echocardiographic Study

Background:

The coronary slow flow phenomenon (CSFP) is the slow passage of the angiographic contrast agent to the distal portion of the coronary artery in the absence of significant stenosis. We evaluated the left atrial (LA) function in patients with the CSFP using two-dimensional speckle-tracking echocardiography (2DSTE).

Methods:

The LA function was compared through 2DSTE between 36 patients with the CSFP and 36 participants with a normal coronary flow. The two groups were matched for age, sex, hypertension, diabetes mellitus, and the left ventricular function.

Results:

There were no statistically significant differences between the CSFP group and the control group regarding longitudinal systolic strain, early and late diastolic strains, and the strain rate of the LA myocardium.

Conclusions:

The LA function as evaluated with 2DSTE was not different between the CSFP group and the normal coronary flow group when they were matched for age, sex, hypertension, diabetes, and the left ventricular function.