Echo-Doppler-derived indexes of ventricular stiffness and ventriculo-arterial interaction as predictors of new-onset atrial fibrillation in patients with heart failure

Impact of Obesity on Ventriculo-Arterial Interaction in Patients After Coarctation of Aorta repair

Survival of patients after repair of coarctation of Aorta (CoA) has improved significantly over the decades, but patients have decreased life expectancy as compared to the general population. This has been attributed to increased hypertension, cerebrovascular disease, and coronary artery disease. There has also been an increasing concern of overweight and obesity in patients with adult congenital heart disease. While there have been studies looking at the impact of long-term hypertension on myocardial performance and outcomes in this population, this study aims to assess the impact of obesity in these patients on their myocardial performance. Ventriculo-arterial coupling is used as a measure of myocardial performance which reflects the interaction between cardiac contractility and arterial elastance. Patients after CoA repair are known to have hypertension affecting the arterial elastance. Obesity affects cardiac contractility as well. This study demonstrated that in a group of young patients after CoA repair, body mass index (BMI) has a relationship with left ventricular (LV) contractility and myocardial performance. This relationship was independent of blood pressure. BMI itself was not seen to affect the determinants of diastolic function in this study, suggesting that LV contractility may be affected before one can notice a change in the diastolic function secondary to BMI.

Predictive Value of Left Atrial and Ventricular Strain for the Detection of Atrial Fibrillation in Patients With Cryptogenic Stroke

Background and Aims

Cryptogenic stroke (CS) is associated with a high rate of recurrences and adverse outcomes at long-term follow-up, especially due to its unknown etiology that often leads to ineffective secondary prevention. Asymptomatic atrial fibrillation (AF) could play an important pathophysiological role. Some studies have pointed to left atrial (LA) and left ventricular (LV) systolic and diastolic dysfunction as surrogate markers of AF. The aim of the study is to evaluate the relationship between echocardiographic parameters of LA and LV function, and the occurrence of AF revealed by continuous ECG monitoring in a cohort of patients with CS.

Methods

Single-center prospective cohort study. Seventy-two patients with CS with insertable cardiac monitors (ICM) underwent transthoracic echocardiography (TTE). TTE was focused on LA and LV function, including both standard and longitudinal strain-derived parameters. All detected AF episodes lasting more than 2 min were considered.

Results

Continuous ECG monitoring revealed subclinical AF in 23 patients (32%) at an average of 6.5 months after ICM implantation. Many echocardiographic parameters, indicating LA volume and LV systolic/diastolic function, were significantly associated with the occurrence of AF, suggesting the worst atrial function in the AF group. Furthermore, multivariable regression analysis revealed that peak atrial contraction strain and left ventricular strain were independently associated with AF (adjusted OR = 0.72, CI 95% 0.48–0.90, p = 0.005, and adjusted OR = 0.69, CI 95% 0.46–0.95, p = 0.041, respectively).

Conclusion

In patients with CS, LA and LV strain analysis add predictive value for the occurrence of AF over clinical and morpho-functional echocardiographic parameters. Impaired booster pump strain and LV longitudinal strain are strong and independent predictors of AF.

Ventricular-arterial coupling in centenarians without cardiovascular diseases

BACKGROUND

Ventricular-arterial (VA) coupling is a central determinant of cardiovascular system performance and cardiac energetics. This index is expressed by the Ea/Ees ratio, where the effective arterial elastance (Ea) indicates the net arterial load exerted on the left ventricle and the left ventricular end-systolic elastance (Ees) is a load-independent measure of left ventricular chamber performance.

METHODS

Thirty-three centenarians (100.6 ± 1.2 years, range 99-105 years, 10 M) without cardiovascular diseases underwent a complete echocardiographic evaluation and an instantaneous arterial blood pressure measurement, to characterize the Ea/Ees ratio and its two determinants indexed to body surface area.

RESULTS

VA coupling was markedly reduced (Ea/Ees ratio 0.40 ± 0.1), reflecting a disproportionate increase in Ees index (8.5 ± 2.2 mmHg/ml/m²) compared with Ea index (3.2 ± 0.8 mmHg/ml/m²). Notably, the coupling ratio was significantly lower in women (0.37 ± 0.1) than in men (0.45 ± 0.1, p = 0.0003), due to an increase in Ees index significantly greater in women (9.4 ± 1.9 mmHg/ml/m²) than in men (6.5 ± 1.5 mmHg/ml/m², p = 0.0002). Using multivariate regression analysis, only female gender (β coefficient -0.04, p = 0.01) and relative wall thickness (β coefficient -0.49, p < 0.0001) showed a significant inverse correlation to VA coupling.

CONCLUSIONS

Our analysis in a population of centenarians without overt cardiovascular disease revealed very low values of VA coupling, especially in women. Both a LV structural remodeling as well as a high aortic elastance might have contributed to a secondary disproportionate increase in myocardial stiffness.

Atrial Arrhythmias and Electroanatomical Remodeling in Patients With Left Ventricular Assist Devices

BACKGROUND

The incidence, predictors, and impact of atrial arrhythmias along with left atrial structural changes in patients with left ventricular assist devices (LVADs) remain undetermined.

METHODS AND RESULTS

All patients who underwent LVAD implantation from 2008 to 2015 at the University of Chicago Medical Center were included. Electronic medical records, electrocardiograms, echocardiograms, and cardiac electrical device interrogations were reviewed. The association of arrhythmias and clinical covariates with survival was evaluated by Kaplan-Meier and Cox proportional hazards analyses. A total of 331 patients were followed for a median of 330 days (range 0-2306 days). Mean age was 57.8±12.8 years, 256 participants (77.3%) were male, mean left ventricular ejection fraction was 20±6.6%, and 124 (37.5%) had ischemic cardiomyopathy. Atrial arrhythmias (53.8%) were highly prevalent and frequently coexisted before LVAD implantation: atrial fibrillation (AF) in 45.9%, atrial flutter in 13.9%, atrial tachycardia in 6.9%, and atrioventricular nodal reentrant tachycardia in 1.2%. New-onset AF was documented in 14 patients (7.8% of patients without prior AF) after the first 30 days with an LVAD. Increasing age, renal insufficiency, and lung disease were predictors of new-onset AF after LVAD implantation. Of patients with paroxysmal AF, 43% had no further AF after LVAD. Left atrial size and volume index improved with LVAD (P<0.005). History of persistent AF, atrial tachycardia, ventricular arrhythmia, coronary artery bypass, and low albumin were associated with decreased survival.

CONCLUSIONS

Atrial arrhythmias are significantly prevalent in patients who require LVAD and are associated with increased mortality; however, LVADs induce favorable atrial structural and electrical remodeling.