The effect of coronary slow flow on left atrial structure and function

Automatic Echocardiographic Assessment of Left Atrial Function for Prediction of Low-Voltage Areas in Non-Valvular Atrial Fibrillation

Purpose

Left atrial low-voltage areas (LA-LVAs) identified by 3D-electroanatomical mapping are crucial for determining treatment strategies and prognosis in patients with atrial fibrillation (AF). However, convenient and accurate prediction of LA-LVAs remains challenging. This study aimed to assess the viability of utilizing automatically obtained echocardiographic parameters to predict the presence of LA-LVAs in patients with non-valvular atrial fibrillation (NVAF).

Patients and Methods

This retrospective study included 190 NVAF patients who underwent initial catheter ablation. Before ablation, echocardiographic data were obtained, left atrial volume and strain were automatically calculated using advanced software (Dynamic-HeartModel and AutoStrain). Electroanatomic mapping (EAM) was also performed. Results were compared between patients with LA-LVAs ≥5% (LVAs group) and <5% (non-LVAs group).

Results

LA-LVAs were observed in 81 patients (42.6%), with a significantly higher incidence in those with persistent AF than paroxysmal AF (55.6% vs 19.3%, P <0.001). Compared with the non-LVAs group, the LVAs group included significantly older patients, lower left ventricular ejection fraction, higher heart rate, and higher E/e' ratio (P <0.05). The LVAs group exhibited higher left atrial volumemax index (LAVimax) and lower left atrial reservoir strain (LASr) (P <0.001). In multivariate analysis, both LAVimax and LASr emerged as independent indicators of LVAs (OR 0.85; 95% CI 0.80-0.90, P<0.001) and (OR 1.15, 95% CI 1.02-1.29, P =0.021). ROC analysis demonstrated good predictive capacity for LA-LVAs, with an AUC of 0.733 (95% CI 0.650-0.794, P <0.001) for LAVimax and 0.839 (95% CI 0.779-0.898, P <0.001) for LASr.

Conclusion

Automatic assessment of LAVimax and LASr presents a promising non-invasive modality for predicting the presence of LA-LVAs and evaluating significant atrial remodeling in NVAF patients. This approach holds potential for aiding in risk stratification and treatment decision-making, ultimately improving clinical outcomes in patients.

Association of central arterial stiffness with atrial myopathy: the Atherosclerosis Risk in Communities (ARIC) study

Atrial myopathy-defined as abnormal left atrial (LA) size and function-is associated with an increased risk of atrial fibrillation, heart failure, and dementia. Central arterial stiffness is associated with increased atrial afterload and fibrosis and may be a risk factor for atrial myopathy. We examined the association of carotid-femoral pulse wave velocity (cfPWV) with LA function and assessed potential causal relationships. We included 2825 Atherosclerosis Risk in Communities (ARIC) study participants from Visit 5 (2011-2013). cfPWV was related to echocardiographic LA function continuously per 1-SD and categorically in quartiles. Mendelian randomization (MR) analysis was performed using U.K. Biobank-derived genetic variants associated with arterial stiffness index and cardiac magnetic resonance measures of LA function. When analyzed per SD increment (297.6 cm/s), higher cfPWV was significantly associated with lower LA reservoir and conduit strain (β = -0.53%, 95% CI [-0.81, -0.25] and β = -0.46%, 95% CI [-0.68, -0.25], respectively) after adjusting for demographics, clinical characteristics, systolic blood pressure, and left ventricular (LV) morphology and function. In MR analyses there was a non-significant inverse association of arterial stiffness index with LA total, passive, and active emptying fractions. Higher cfPWV is associated with lower LA reservoir and conduit strain, independent of systolic blood pressure and LV morphology and function. No evidence for a causal relationship between arterial stiffness index and alterations in LA function was found. Future studies should examine the prospective association of central arterial stiffness with LA function alterations.

The predictors of coronary slow flow in patients undergoing coronary angiography

BACKGROUND

A new challenge in coronary artery disease treatment has emerged, where specific populations exhibit ischemic symptoms without any obstruction in the epicardial coronary artery. Instead, they exhibit slow coronary contrast flow, referred to as coronary slow flow (CSF). This study aims to identify several predictors of CSF.

RESULTS

This case-control study was conducted at the Regional General Hospital of West Nusa Tenggara Province in Indonesia from December 2016 to February 2024. The study involved sixty subjects, with 30 in each group of CSF and normal epicardial coronary artery angiogram (NECA). CSF is enforced by the TIMI frame count (TFC) greater than 27 frames. Among all the predictors studied, coronary artery diameter (p < 0.001) and random blood sugar (p = 0.049) were found to affect the CSF significantly. In the multivariate analysis, coronary artery diameter remained a significant predictor (adjusted OR 10.08, 95% CI 2.64-38.50, p < 0.001), with an optimal cut-off point of more than 3.56 mm, a sensitivity of 76.7%, and a specificity of 70.7% (AUC = 0.787, p < 0.001).

CONCLUSION

The coronary artery diameter strongly predicts CSF in patients undergoing coronary angiography.

Association of Left Atrial Function With Incident Chronic Kidney Disease in Older Adults

Objective

To examine the association of left atrial (LA) function with incident chronic kidney disease (CKD) and assess the clinical utility of adding LA function to a CKD risk prediction equation.

Patients and Methods

We included 4002 Atherosclerosis Risk in Communities study participants without prevalent CKD (mean ± SD age, 75±5 years; 58% female, 18% Black). Left atrial function (reservoir, conduit, and contractile strain) was evaluated by 2D-echocardiograms on 2011 to 2013. Chronic kidney disease was defined as greater than 25% decline in estimated glomerular filtration rate of less than 60 mL/min/1.73 m2, end-stage kidney disease, or hospital records. Cox proportional hazards models were used. Risk prediction and decision curve analyses evaluated 5-year CKD risk by diabetes status.

Results

Median follow-up was 7.2 years, and 598 participants developed incident CKD. Incidence rate for CKD was 2.29 per 100 person-years. After multivariable adjustments, the lowest quintile of LA reservoir, conduit, and contractile strain (vs highest quintile) had a higher risk of CKD (hazard ratios [95% CIs]: 1.94 [1.42-2.64], 1.62 [1.19-2.20], and 1.49 [1.12-1.99]). Adding LA reservoir strain to the CKD risk prediction equation variables increased the C-index by 0.026 (95% CI: 0.005-0.051) and 0.031 (95% CI: 0.006-0.058) in participants without and with diabetes, respectively. Decision curve analysis found the model with LA reservoir strain had a higher net benefit than the model with CKD risk prediction equation variables alone.

Conclusion

Lower LA function is independently associated with incident CKD. Adding LA function to the CKD risk prediction enhances prediction and yields a higher clinical net benefit. These findings suggest that impaired LA function may be a novel risk factor for CKD.

Coronary slow flow and angiography-derived index of microcirculatory resistance as prognostic predictors in patients with angina and normal coronary arteries: a retrospective cohort study

BACKGROUND

This study aims to investigate prognostic implications of coronary slow flow (CSF) and angiography-derived index of microcirculatory resistance (caIMR) in patients with angina and normal coronary arteries.

METHODS

A total of 582 patients were enrolled with angiographically normal coronary arteries. caIMR was calculated using a commercial software. Patients were followed up for a median of 45 months. The primary endpoint was defined as major adverse cardiovascular events (MACEs) comprising death, myocardial infarction and readmission for angina or heart failure.

RESULTS

CSF was diagnosed when TIMI grade 2 flow presented in at least one coronary artery. Multivariate analysis indicated TIMI-flow-based determination of CSF was not significantly associated with MACEs [hazard ratio (HR): 2.14; 95% confidence interval (CI): 0.87-5.31; p = 0.099), while caIMR >42 (HR: 2.53; 95% CI: 1.02-6.32; p = 0.047) were independent predictors of MACEs. Incorporation of caIMR improved the area under the curve from 0.587 to 0.642.

CONCLUSIONS

caIMR was an independent prognostic factor of long-term cardiovascular events in patients with CSF. Evaluation of caIMR improved the risk stratification of patients with angiographically-normal coronary arteries.

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.

The Effect of Chronic Inhouse Biomass Fuel Smoke Exposure on Coronary Slow Flow Phenomenon in Women Living in the Eastern Region of Turkey

Objective:

Biomass fuel (BMF) is still widely used in rural areas for cooking and heating worldwide. BMF smoke inhalation is a prominent cause of respiratory and cardiovascular disease. The slow coronary flow (SCF) phenomenon is known as the delayed opacification of distal coronary arteries on a coronary angiogram. SCF is known to be related to cardiovascular morbidity and mortality. Thus, we aimed to investigate the relationship between exposure to BMF and SCF in women in this study.

Methods:

A total of 457 consecutive women who underwent coronary angiography were retrospectively enrolled in this study. Patients were divided into two groups according to the use of BMF during their lives, from birth to older ages, as biomass exposure group (BEG) and non-exposure group. The presence of SCF was calculated based on thrombolysis in myocardial infarction frame count.

Results:

Two hundred fifty nine patients were in the BEG, whereas 198 patients were in the non-exposure group. The prevalence of SCF was higher in the BEG compared to the non-exposure group (47.9% vs. 13.1%, respectively, p<0.001). The presence of biomass exposure, body mass index, white blood cell count, low-density lipoprotein cholesterol, C-reactive protein, serum creatinine, and hypertension were independent predictors of SCF. The optimal cutoff point of biomass exposure time in years to detect the presence of SCF was 30 years (Area under the curve: 0.71, sensitivity: 0.65, specifity: 0.71).

Conclusions:

Exposure to indoor BMF was associated with a SCF phenomenon in women.