Left atrial myocardial dysfunction in patients with primary aldosteronism as assessed by speckle-tracking echocardiography

Correlation between Heart rate recovery and Left Atrial phasic functions evaluated by 2D speckle-tracking Echocardiography after Acute Myocardial infarction

BACKGROUND

Heart rate recovery (HRR) in the exercise test is the index of cardiac autonomic system function and sympathovagal balance impaired in patients with myocardial infarction (MI). An instance is left atrial (LA) phasic function, which is impaired in such patients. In this study, we investigated the role of HRR in predicting LA phasic functions in patients with MI.

METHODS

The present study recruited 144 consecutive patients with ST-elevation MI. A symptom-limited exercise test was performed about 5 weeks after MI, with echocardiography conducted just before the exercise test. The patients were divided into abnormal and normal HRR at 60 s (HRR60) and again into abnormal and normal HRR at 120 s (HRR120) after the exercise test. LA phasic functions, evaluated by 2D speckle-tracking echocardiography, were compared between the 2 groups.

RESULTS

Patients with abnormal HRR120 had lower LA strain values and strain rates during the reservoir, conduit, and contraction phases, while those with abnormal HRR60 had lower LA strain values and strain rates during the reservoir and conduit phases. The differences were lost after adjustments for possible confounders, except for LA strain and strain rate during the conduit phase, in patients with abnormal HRR120.

CONCLUSIONS

Abnormal HRR120 in the exercise test can independently predict decreased LA conduit function in patients with ST-elevation MI.

Role of α1-blockers in the current management of hypertension

There is emerging evidence that α1-blockers can be safely used in the treatment of hypertension. These drugs can be used in almost all hypertensive patients for blood pressure control. However, there are several special indications. Benign prostatic hyperplasia is a compelling indication of α1-blockers, because of the dual treatment effect on both high blood pressure and lower urinary tract symptoms. Many patients with resistant hypertension would require α1-blockers as add-on therapy. Primary aldosteronism screen is a rapidly increasing clinical demand in the management of hypertension, where α1-blockers are useful for blood pressure control in the preparation for the measurement of plasma aldosterone and renin. Nonetheless, α1-blockers have to be used under several considerations. Among the currently available agents, only long-acting α1-blockers, such as doxazosin gastrointestinal therapeutic system 4-8 mg daily and terazosin 2-4 mg daily, should be chosen. Orthostatic hypotension is a concern with the use of α1-blockers especially in the elderly, and requires careful initial bedtime dosing and avoiding overdosing. Fluid retention is potentially also a concern, which may be overcome by combining an α1-blocker with a diuretic.

Strain Imaging for the Early Detection of Cardiac Remodeling and Dysfunction in Primary Aldosteronism

Speckle tracking echocardiography is a novel technique to quantify cardiac function and deformation. It has been applied in a series of cardiovascular diseases for the evaluation of early cardiac impairment. We recently used this technique to investigate cardiac structure and function in patients with primary aldosteronism. Cardiac damage usually occurs earlier in patients with primary aldosteronism than those with primary hypertension, probably because aldosterone hypersecretion is more commonly observed in the former than the latter patients. In this article, we will review the imaging studies, especially with speckle tracking echocardiography, for the detection of early cardiac dysfunction in primary aldosteronism as a disease model.

Myocardial mechano-energetic efficiency in primary aldosteronism

BACKGROUND

Available data indicate that patients with primary aldosteronism have an increased risk of cardiovascular events and cardiovascular risk seems to be, at least in part, independent of blood pressure (BP) values. Patients with primary aldosteronism have a greater prevalence of left ventricular (LV) hypertrophy and subtle alterations of ventricular function, which might contribute to the increase in cardiovascular risk. Recently, a noninvasive approach for the estimation of LV mechanical efficiency, obtained by echocardiography has been proposed.

AIM OF THE STUDY

To evaluate the determinants of myocardial mechanoenergetic efficiency index (MEEi), in a large group of patients with primary aldosteronism (n = 99) and in a control group of essential hypertensive patients (n = 99) matched for age, sex and BP values.

RESULTS

No differences between groups for age, sex, BMI, BP values, glucose, lipid profile and renal function were observed. LV mass index was greater in primary aldosteronism vs. essential hypertensive patients (46.0 ± 16.7 vs. 36.9 ± 8.6 g/m2, P < 0.001); also relative wall thickness was greater in primary aldosteronism (0.36 ± 0.1 vs. 0.32 ± 0.4, P < 0.001). Left atrial dimensions were significantly greater in primary aldosteronism. Ejection fraction was not different between groups, while endocardial and midwall fractional shortening were lower in primary aldosteronism vs. essential hypertensive patients (40 ± 7 vs. 43 ± 6, and 18 ± 3 vs. 21 ± 2, both P < 0.01). MEEi was lower in primary aldosteronism vs. essential hypertensive patients (0.44 ± 0.14 vs. 0.52 ± 0.10 ml/s per g, P < 0.01). A negative correlation was observed between MEEi and aldosterone levels (r = -0.203, P < 0.05) and aldosterone : renin ratio (P = -0.172, P < 0.05); the correlation remained significant after adjustment for possible confounders.

CONCLUSION

In patients with primary aldosteronism myocardial MEEi is lower as compared with essential hypertensive patients. A reduced MEEi may reflect an impairment of production and utilization of energy in the myocardium, which could lead to the occurrence of cardiovascular complications and therefore these findings may contribute to explain the increased risk of cardiovascular events in patients with primary aldosteronism.

Factors affecting the urinary aldosterone-to-creatinine ratio in healthy dogs and dogs with naturally occurring myxomatous mitral valve disease

BACKGROUND

Chronic renin-angiotensin-aldosterone system (RAAS) activation in course of heart diseases contributes to cardiac remodeling and heart failure. Myxomatous mitral valve disease (MMVD) is characterized by different stages of severity and trend of RAAS activity during the course of the disease is still uncertain. The urinary aldosterone-to-creatinine ratio (UAldo:C) has been proven to reflect RAAS activation in dogs and might be a useful marker in monitoring therapy and disease progression, but data about this parameter need to be expanded. The objective of this study was to evaluate the UAldo:C in healthy dogs and dogs with naturally occurring MMVD, and to investigate the relationships between this parameter and clinical, echocardiographic and laboratory variables.

RESULTS

The study population consisted of 149 dogs: 49 healthy and 100 MMVD dogs (45 stage B1, 13 stage B2 and 42 stage C). Urinary aldosterone-to-creatinine ratio was not significantly different among healthy and MMVD dogs of any stages. Breed, sex and age showed a significant impact on UAldo:C. In particular, Chihuahua and Cavalier King Charles spaniel showed significantly higher UAldo:C than other breeds, as well as intact females than other genders. In stage C dogs, UAldo:C appeared to be increased by spironolactone and was positively associated with furosemide dose (P = 0.024). Aldosterone breakthrough (ABT) appeared to occur in 36% (8/22) of stage C dogs not receiving spironolactone. A significant positive association between UAldo:C and left atrium-to-aortic root ratio (LA/Ao) was found.

CONCLUSIONS

Individual factors such as breed, sex and age appeared to influence UAldo:C, and therapy seemed to add further variability. In the light of these results, comparing the UAldo:C of a single patient with a population-based reference value might lead to wrong interpretations and an individual monitoring should be considered. The prevalence of ABT in the present study (36%) was in line with those previously reported. However, due to the high individual variability of UAldo:C found in the study, even this result should be re-evaluated in the setting of an individual longitudinal approach. The positive association between UAldo:C and LA/Ao supports the mutual relationship between RAAS and cardiac remodeling.

Left ventricular remodeling and dysfunction in primary aldosteronism

Primary aldosteronism (PA) is a common cause of secondary hypertension and is associated with worse cardiovascular outcomes. The elevated aldosterone in PA leads to left ventricular (LV) remodeling and dysfunction. In recent decades, clinical studies have demonstrated worse LV remodeling including increased LV mass and cardiac fibrosis in patients with PA compared to patients with essential hypertension. Several mechanisms may explain the process of aldosterone-induced LV remodeling, including directly profibrotic and hypertrophic effects of aldosterone on myocardium, increased reactive oxygen species and profibrotic molecules, dysregulation of extracellular matrix metabolism, endothelium dysfunction and circulatory macrophages activation. LV remodeling causes LV diastolic and systolic dysfunction, which may consequently lead to clinical complications such as heart failure, atrial fibrillation, ischemic heart disease, and other vascular events. Adequate treatment with adrenalectomy or medical therapy can improve LV remodeling and dysfunction in PA patients. In this review, we discuss the mechanisms of aldosterone-induced LV remodeling and provide an up-to-date review of clinical research about LV remodeling-related heart structural changes, cardiac dysfunction, and their clinical impacts on patients with PA.

A speckle tracking echocardiographic study on right ventricular function in primary aldosteronism

OBJECTIVE

We investigated right ventricular function using speckle tracking echocardiography (STE) in patients with primary aldosteronism.

METHODS

Our study included 51 primary aldosteronism patients and 50 age and sex-matched primary hypertensive patients. We performed two-dimensional echocardiography to measure cardiac structure and function. We performed STE offline analysis on right ventricular four-chamber (RV4CLS) and free wall longitudinal strains (RVFWLS).

RESULTS

Primary aldosteronism patients, compared with primary hypertensive patients, had a significantly (P ≤ 0.045) greater left ventricular mass index (112.0 ± 22.6 vs. 95.8 ± 18.5 g/m) and left atrial volume index (26.9 ± 6.0 vs. 24.7 ± 5.6 ml/m) and higher prevalence of left ventricular concentric hypertrophy (35.3 vs. 12.0%), although they had similarly normal left ventricular ejection fraction (55-77%). Primary aldosteronism patients also had a significantly (P ≤ 0.047) larger right atrium and ventricle, lower tricuspid annular plane systolic excursion, and higher E/E't (the peak early filling velocity of trans-tricuspid flow to the peak early filling velocity of lateral tricuspid annulus ratio), estimated pulmonary arterial systolic pressure and right ventricular index of myocardial performance. On the right ventricular strain analysis, primary aldosteronism patients had a significantly (P < 0.001) lower RV4CLS (-18.1 ± 2.5 vs. -23.3 ± 3.4%) and RVFWLS (-21.7 ± 3.7 vs. -27.9 ± 4.5%) than primary hypertensive patients. Overall, RV4CLS and RVFWLS were significantly (r = -0.58 to -0.41, P < 0.001) correlated with plasma aldosterone concentration and 24-h urinary aldosterone excretion. After adjustment for confounding factors, the associations for RV4CLS and RVFWLS with 24-h urinary aldosterone excretion remained significant (P < 0.001), with a standardized coefficient of -0.48 and -0.55, respectively.

CONCLUSION

In addition to left ventricular abnormalities, primary aldosteronism patients also show impaired right ventricular function, probably because of hyperaldosteronism.

Current advances in the study of diabetic cardiomyopathy: From clinicopathological features to molecular therapeutics (Review)

The incidence of diabetes mellitus has become a major public health concern due to lifestyle alterations. Moreover, the complications associated with diabetes mellitus deeply influence the quality of life of patients. Diabetic cardiomyopathy (DC) is a type of diabetes mellitus complication characterized by functional and structural damage in the myocardium but not accompanied by coronary arterial disease. Currently, diagnosing and preventing DC is still a challenge for physicians due to its atypical symptoms. For this reason, it is necessary to summarize the current knowledge on DC, especially in regards to the underlying molecular mechanisms toward the goal of developing useful diagnostic approaches and effective drugs based on these mechanisms. There exist several review articles which have focused on these points, but there still remains a lot to learn from published studies. In this review, the features, diagnosis and molecular mechanisms of DC are reviewed. Furthermore, potential therapeutic and prophylactic drugs are discussed.