Exercise-Induced Atrial Remodeling: The Forgotten Chamber

Left atrial volume changes during exercise stress echocardiography in heart failure and hypertrophic cardiomyopathy: Exercise echocardiography and left atrial changes

BACKGROUND

We assessed feasibility and functional correlates of LAVI (left atrial volume index) changes during exercise stress echocardiography (ESE).

METHODS

ESE on bike or treadmill was performed in 363 patients with heart failure with preserved ejection fraction (HFpEF, n = 173), reduced ejection fraction (HFrEF, n = 59) or hypertrophic cardiomyopathy (HCM, n=131). LAVI stress-rest increase ≥ 6.8 ml/m² was defined as dilation.

RESULTS

LAVI measurements were feasible in 100%. LAVI did not change in HFrEF being at rest 32 (25-45) vs. at stress 36 (24 - 54) ml/m², P = NS and in HCM at rest 35 (26 - 48) vs. at stress 38 (28 - 48) ml/m², P = NS whereas it decreased in HFpEF from 30 (24 -40) to 29 (21 - 37) ml/m² at stress, P = 0.007. LA dilation occurred in 107 (30%) patients (27% with treadmill vs. 33% with bike ESE, P = NS): 26 with HFpEF (15%), 26 with HFrEF (44%) and 55 with HCM (42%) with P < 0.001 for HFrEF and HCM vs. HFpEF. Multivariate analysis revealed as the predictors for LAVI dilation E/e' > 14 at rest with OR 4.4, LVEF < 50% with OR 2.9, and LAVI at rest < 35 ml/m² with OR 2.7.

CONCLUSION

LAVI assessment during ESE was highly feasible and dilation equally frequent with treadmill or bike. LA dilation was threefold more frequent in HCM and HFrEF and could be predicted by increased resting E/e' and impaired EF as well as smaller baseline LAVI.

Heart in Acromegaly: The Echocardiographic Characteristics of Patients Diagnosed with Acromegaly in Various Stages of the Disease

To determine whether the echocardiographic presentation allows for diagnosis of acromegalic cardiomyopathy. 140 patients with acromegaly underwent echocardiography as part of routine diagnostics. The results were compared with the control group comprising of 52 age- and sex-matched healthy volunteers. Patients with acromegaly presented with higher BMI, prevalence of arterial hypertension, and glucose metabolism disorders (i.e., diabetes and/or prediabetes). In patients with acromegaly, the following findings were detected: increased left atrial volume index, increased interventricular septum thickness, increased posterior wall thickness, and increased left ventricular mass index, accompanied by reduced diastolic function measured by the following parameters: E'med., E/E', and E/A. Additionally, they presented with abnormal right ventricular systolic pressure. All patients had normal systolic function measured by ejection fraction. However, the values of global longitudinal strain were slightly lower in patients than in the control group; the difference was statistically significant. There were no statistically significant differences in the size of the right and left ventricle, thickness of the right ventricular free wall, and indexed diameter of the ascending aorta between patients with acromegaly and healthy volunteers. None of 140 patients presented systolic dysfunction, which is the last phase of the so-called acromegalic cardiomyopathy. Some abnormal echocardiographic parameters found in acromegalic patients may be caused by concomitant diseases and not elevated levels of GH or IGF-1 alone. The potential role of demographic parameters like age, sex, and/or BMI requires further research.

Cardiac damage in athlete’s heart: When the “supernormal” heart fails!

Intense exercise may cause heart remodeling to compensate increases in blood pressure or volume by increasing muscle mass. Cardiac changes do not involve only the left ventricle, but all heart chambers. Physiological cardiac modeling in athletes is associated with normal or enhanced cardiac function, but recent studies have documented decrements in left ventricular function during intense exercise and the release of cardiac markers of necrosis in athlete’s blood of uncertain significance. Furthermore, cardiac remodeling may predispose athletes to heart disease and result in electrical remodeling, responsible for arrhythmias. Athlete’s heart is a physiological condition and does not require a specific treatment. In some conditions, it is important to differentiate the physiological adaptations from pathological conditions, such as hypertrophic cardiomyopathy, arrhythmogenic dysplasia of the right ventricle, and non-compaction myocardium, for the greater risk of sudden cardiac death of these conditions. Moreover, some drugs and performance-enhancing drugs can cause structural alterations and arrhythmias, therefore, their use should be excluded.

Acute and Chronic Response to Exercise in Athletes: The "Supernormal Heart"

During last decades, most studies have examined the exercise-induced remodeling defined as "athlete's heart". During exercise, there is an increased cardiac output that causes morphological, functional, and electrical modification of the cardiac chambers. The cardiac remodeling depends also on the type of training, age, sex, ethnicity, genetic factors, and body size. The two main categories of exercise, endurance and strength, determine different effects on the cardiac remodeling. Even if most sport comprise both strength and endurance exercise, determining different scenarios of cardiac adaptation to the exercise. The aim of this paper is to assemble the current knowledge about physiologic and pathophysiologic response of both the left and the right heart in highly trained athletes.