Independent and incremental value of severely enlarged left atrium in risk stratification of very elderly patients with chronic systolic heart failure

The correlation between the left atrial volume index and atrial fibrillation development in heart failure with mildly reduced ejection fraction and long-term follow-up results

BACKGROUND

The European Society of Cardiology has recently defined heart failure (HF) patient group with a left ventricular ejection fraction (LVEF) of 41-49% as a different category with the term heart failure with mildly reduced ejection fraction (HFmrEF). In this study, we aimed to conduct a research about the correlation between left atrial volume index (LAVI) and atrial fibrillation in patients HFmrEF.

METHODS

A total of 282 patients HFmrEF who were admitted to the cardiology department from three different centres were included in the study. The study was planned as multicenter, cross-sectional study. The patients were divided into two groups as sinus rhythm and atrial fibrillation based on their electrocardiographic findings.

RESULTS

It was found out that Nt-ProBNP, LA area, LAVI, pulmonary artery pressure, and severe mitral regurgitation rates were significantly higher in the AF group (p < 0.001). ROC analysis resulting in LAVI > 30.5 had 64% sensitivity and 66% specificity in the predicting presence of AF (ROC area under the curve: 0.660, 95% CI: 0.587-0.733, p < 0.001). We also observed that the LA area being >16.55 predicting presence of AF with 60% sensitivity and 58% specificity (ROC area under the curve: 0.624, 95% CI: 0.549-0.699, p = 0.002).

CONCLUSION

In the study conducted, we found a correlation between AF and LAVI values in patients in the HFmrEF group. If the LAVI value increases in the follow-up of this group of patients with echocardiography, close follow-up in terms of AF may allow the early control and treatment of AF-related incidents.

Diuretic Resistance in Cardio-Nephrology: Role of Pharmacokinetics, Hypochloremia, and Kidney Remodeling

Background: Diuretic resistance is among the most challenging problems that the cardio-nephrologist must address in daily clinical practice, with a considerable burden on hospital admissions and health care costs. Indeed, loop diuretics are the first-line therapy to overcome fluid overload in heart failure patients. The pathophysiological mechanisms of fluid and sodium retention are complex and depend on several neuro-hormonal signals mainly acting on sodium reabsorption along the renal tubule. Consequently, doses and administration modalities of diuretics must be carefully tailored to patients in order to overcome under- or overtreatment. The frequent and tricky development of diuretic resistance depends in part on post-diuretic sodium retention, reduced tubular secretion of the drug, and reduced sodium/chloride sensing. Sodium and chloride depletions have been recently shown to be major factors mediating these processes. Aquaretics and high-saline infusions have been recently suggested in cases of hyponatremic conditions. This review discusses the limitations and strengths of these approaches. Summary: Long-term diuretic use may lead to diuretic resistance in cardio-renal syndromes. To overcome this complication intravenous administration of loop diuretics and a combination of different diuretic classes have been proposed. In the presence of hyponatremia, high-saline solutions in addition to loop diuretics might be beneficial, whereas aquaretics require caution to avoid overcorrection. Key Messages: Diuretic resistance is a central theme for cardio-renal syndromes. Hyponatremia and hypochloremia may be part of the mechanisms for diuretic resistance. Aquaretics and high-saline solutions have been proposed as possible new therapeutic solutions.

Determinants of Normal Left Atrial Volume in Heart Failure with Moderate-to-Severely Reduced Ejection Fraction

Background

Indexed left atrial volume (LAVi) is a robust predictor of adverse cardiovascular events. A minority of patients with moderate-to-severe left ventricular (LV) systolic dysfunction maintain normal LAVi. We followed clinical and echocardiographic parameters for at least 6 months to understand how this population is different from patients with similar systolic dysfunction and dilated left atria.

Methods and Results

We searched our electronic medical records for "normal" (n=817) and "severely dilated" (n=1094) LA size and LV ejection fraction (EF) ≤ 35% on echocardiogram reports from 2009 to 2015. We analyzed 115 subjects for LAVi, biplane EF, and diastolic parameters over 2 echocardiograms at least 6 months apart. Younger age, white race, being on an angiotensin-converting enzyme inhibitor, smaller end-diastolic LV volume (LVEDV), and longer deceleration time (DT) were associated with having a normal LAVi. The receiver-operating characteristic curve has an area under the curve of 0.95 (p < 0.0001) for this model. An increase in LVESVi and early mitral flow velocity and a decrease in DT explain 32% of the variance seen in LAVi increase over time.

Conclusion

In patients with moderate-to-severely reduced EF, younger age, being on heart failure therapies, and better diastolic dysfunction were independently associated with a normal LAVi. Improvement in systolic and diastolic performances was associated with decreasing LAVi with 6-month to 1-year follow-up.

Left atrial changes in early stages of heart failure with preserved ejection fraction

BACKGROUND AND AIM

Increased left atrial (LA) mass was introduced as a compensatory mechanism in heart failure (HF) patients. Furthermore, atrial conduction time and LA emptying fraction is are deteriorated in HF with preserved ejection fraction (HFpEF). The aim of this study was to assess the early LA changes in HFpEF patients.

METHODS

In 79 consecutive patients with HFpEF (age 61±8 years, NYHA class I-III, LV EF ≥45%), a complete 2-dimensional, M-mode, and Doppler echocardiographic study was performed. According to the diastolic dysfunction (DD), patients were divided into three groups: Group I-29 healthy subjects (control group); Group II-HFpEF patients with mild DD; and Group III-HFpEF patients with moderate DD.

RESULTS

The LV mass was increased (P<.05), septal s', lateral s', septal and lateral MAPSE were decreased (P<.05, for all), E/e' ratio was increased (P<.001), LA mass and minimal volume were increased (P<.001, P<.05), LA emptying fraction was decreased (P<.05), and LA dyssynchrony was deteriorated (P<.05) in patients with mild DD compared to controls. These changes were of the same nature in patients with moderate LV DD.

CONCLUSIONS

In early stage of DD, in patients with HFpEF, in addition to LV hypertrophy and compromised LV longitudinal systolic function, the LA emptying fraction is reduced, LA mass and LAV min are increased and LA dyssynchrony is significant, despite normal LA dimensions. These findings suggest early LA function deterioration irrespective of normal cavity measurements, hence a need for optimum therapy.

Left atrial emptying fraction predicts limited exercise performance in heart failure patients

AIM

We aimed in this study to assess the role of left atrial (LA), in addition to left ventricular (LV) indices, in predicting exercise capacity in patients with heart failure (HF).

METHODS

This study included 88 consecutive patients (60 ± 10 years) with stable HF. LV end-diastolic and end-systolic dimensions, ejection fraction (EF), mitral and tricuspid annulus peak systolic excursion (MAPSE and TAPSE), myocardial velocities (s', e' and a'), LA dimensions, LA volume and LA emptying fraction were measured. A 6-min walking test (6-MWT) distance was performed on the same day of the echocardiographic examination.

RESULTS

Patients with limited exercise performance (≤ 300 m) were older (p = 0.01), had higher NYHA functional class (p = 0.004), higher LV mass index (p = 0.003), larger LA (p = 0.002), lower LV EF (p = 0.009), larger LV end-systolic dimension (p = 0.007), higher E/A ratio (p = 0.03), reduced septal MAPSE (p < 0.001), larger LA end-systolic volume (p = 0.03), larger LA end-diastolic volume (p = 0.005) and lower LA emptying fraction (p < 0.001) compared with good performance patients. In multivariate analysis, only the LA emptying fraction [0.944 (0.898-0.993), p = 0.025] independently predicted poor exercise performance. An LA emptying fraction < 60% was 68% sensitive and 73% specific (AUC 0.73, p < 0.001) in predicting poor exercise performance.

CONCLUSION

In heart failure patients, the impaired LA emptying function is the best predictor of poor exercise capacity. This finding highlights the need for routine LA size and function monitoring for better optimization of medical therapy in HF.