Diastolic dysfunction and diastolic heart failure: mechanisms and epidemiology

Considering impact of age and sex on cardiac cytoskeletal components

The cardiac cytoskeletal components are integral to cardiomyocyte function and are responsible for contraction, sustaining cell structure, and providing scaffolding to direct signaling. Cytoskeletal components have been implicated in cardiac pathology; however, less attention has been paid to age-related modifications of cardiac cytoskeletal components and how these contribute to dysfunction with increased age. Moreover, significant sex differences in cardiac aging have been identified, but we still lack a complete understanding to the mechanisms behind these differences. This review summarizes what is known about how key cardiomyocyte cytoskeletal components are modified because of age, as well as reported sex-specific differences. Thorough consideration of both age and sex as integral players in cytoskeletal function may reveal potential avenues for more personalized therapeutics.

Psychological Health and Ischemic Heart Disease in Women: A Review of Current Evidence and Clinical Considerations across the Healthspan

PURPOSE OF REVIEW

Psychological health encompasses a constellation of negative and positive factors-i.e., psychosocial stress, depression, anxiety, trauma, loneliness and social isolation, anger and hostility, optimism, and a sense of purpose. This narrative review presents current evidence at the intersection of psychological health, risk of ischemic heart disease (IHD), and IHD-related outcomes, with an emphasis on associations in women.

RECENT FINDINGS

For women, relations between psychological health and IHD reflect important sex and gender differences in biological and psychosocial factors. Although efforts devoted to understanding psychological health and IHD risk have varied by psychological factor-scientific evidence is strongest for psychosocial stress and depression, while anxiety, trauma, and positive psychological factors warrant more investigation-less optimal psychological health is consistently associated with an earlier and greater risk of IHD morbidity and mortality in women. Still, many past prospective studies of psychological factors and IHD risk had a limited representation of women, did not include analyses by sex, or failed to account for other influential, sex-specific factors. Thus, there are multiple pathways for further, rigorous investigation into psychological health-IHD associations, mechanisms, and empirically supported psychological interventions to mitigate IHD risk among women. Given the robust evidence linking psychological health with women's risk for IHD, implementing routine, brief, psychological screening is recommended. Significant life events, developmental milestones specific to women, and IHD diagnoses or events could cue further psychological assessment and referral, efforts which will mutually strengthen the evidence for integrated psychological and IHD care and delivery of such care to this vulnerable group.

Therapeutic Aspects of Prunus cerasus Extract in a Rabbit Model of Atherosclerosis-Associated Diastolic Dysfunction

This study evaluates the potential therapeutic effects of anthocyanin-rich Prunus cerasus (sour cherry) extract (PCE) on atherosclerosis-associated cardiac dysfunction, described by the impairment of the NO-PKG (nitric oxide-protein kinase G) pathway and the antioxidant capacity. Initially, a rabbit model of atherosclerotic cardiovascular disease was established by administering a cholesterol-rich diet, enabling the examination of the impact of 9 g/kg PCE on the pre-existing compromised cardiovascular condition. After that, the animals were divided into four groups for 12 weeks: the (1) untreated control group; (2) PCE-administered healthy rabbits; (3) hypercholesterolemic (HC) group kept on an atherogenic diet; and (4) PCE-treated HC group. Dyslipidemia, impaired endothelial function, and signs of diastolic dysfunction were evident in hypercholesterolemic rabbits, accompanied by a reduced cardiac expression of eNOS (endothelial nitric oxide synthase), PKG, and SERCA2a (sarco/endoplasmic reticulum calcium ATPase 2a). Subsequent PCE treatment improved the lipid profile and the cardiac function. Additionally, PCE administration was associated with elevated myocardial levels of eNOS, PKG, and SERCA2a, while no significant changes in the vascular status were observed. Western blot analysis further revealed hypercholesterolemia-induced increase and PCE-associated reduction in heme oxygenase-1 expression. The observed effects of anthocyanins indicate their potential as a valuable addition to the treatment regimen for atherosclerosis-associated cardiac dysfunction.

Risk factors of left ventricular diastolic dysfunction in maintenance hemodialysis patients

OBJECTIVE

To investigate the risk factors of left ventricular diastolic dysfunction in maintenance hemodialysis (MHD) patients.

METHOD

We retrospectively collected data from 363 hemodialysis patients who were on dialysis for at least 3 months at January 1, 2020. According to the echocardiogram results, these patients were divided into left ventricular diastolic dysfunction (LVDD) group and non-LVDD group. The differences in basic data, cardiac structure and functiona between the two groups were analyzed. Logistic regression analysis was used to analyze the risk factors of cardiac diastolic dysfunction in MHD patients.

RESULTS

Compared with the non-LVDD group, patients in the LVDD group were older, with an increased proportion of coronary heart disease, more prone to chest tightness, shortness of breath. Simultaneously, they had a significantly increased (p < 0.05) proportion of cardiac structural abnormalities such as left ventricular hypertrophy, left heart enlargement and systolic dysfunction. Multivariate logistic regression analysis showed that the risk of LVDD was significantly increased in elderly MHD patients older than 60 years (OR = 3.86, 95%CI 1.429-10.429), and left ventricular hypertrophy was also significantly associated with LVDD (OR = 2.227, 95% CI 1.383-3.586).

CONCLUSION

According to research, both age and left ventricular hypertrophy are risk factors for LVDD in MHD patients. It is recommended that early intervention for LVDD should be implemented to improve the quality of dialysis and reduce the incidence of cardiovascular events in MHD patients.

Dysfunctional sarcomeric relaxation in the heart

Since cardiac relaxation is commonly impaired in heart failure caused by many different etiologies, identifying druggable targets is a common goal. While many factors contribute to cardiac relaxation, this review focuses on sarcomeric relaxation and dysfunction. Any alteration in how sarcomeric proteins interact can lead to significant shifts in sarcomeric relaxation that may contribute to diastolic dysfunction. Considering examples of sarcomeric dysfunction that have been reported in 3 different pathologies, hypertrophic cardiomyopathy, restrictive cardiomyopathy, and heart failure with preserved ejection fraction, will provide insights into the role sarcomeric dysfunction plays in impaired cardiac relaxation. This will ultimately improve our understanding of sarcomeric physiology and uncover new therapeutic targets.

E/E′ Is a New Independent Predictor of Recovered Ejection Fraction in Patients With Systolic Heart Failure Undergoing Ablation for Atrial Fibrillation

Aims: Catheter ablation should be considered in patients with atrial fibrillation (AF) and with heart failure (HF) with reduced ejection fraction (EF; HFrEF) to improve survival and reduce heart failure hospitalization. Careful patient selection for AF ablation is key to achieving similar outcome benefits. However, limited data exist regarding predictors of recovered ejection fraction. We aimed to evaluate the predictors of recovered ejection fraction in consecutive patients with HF undergoing AF ablation.

Methods and Results: A total of 156 patients [67.3% men, median age 63 (11)] with AF and HF underwent initial catheter ablation between September 2017 and October 2019 in the First Affiliated Hospital of Dalian Medical University. Overall, the percentage of recovered ejection fractions was 72.3%. Recovered EFs were associated with a 39% reduction in all-cause hospitalization compared to non-recovered EFs at the 1-year follow-up [23.8 vs. 62.8 (odds ratio) OR 2.09 (1.40–3.12), P < 0.001]. Univariate analysis for recovered EFs showed that diabetes (P = 0.083), prevalent HF (P = 0.014), prevalent AF (P = 0.051), LVEF (P = 0.022), and E/E′ (P = 0.001) were associated with EF improvement. Multivariate analysis showed that the only independent predictor of EF recovery was E/E′ [OR 1.13 (1.03–1.24); P = 0.011]. A receiver operating characteristic analysis determined that the suitable cut-off value for E/E′ was 15 (sensitivity 38.7%, specificity 89.2%, the area under curve 0.704).

Conclusions: Ejection fraction (EF) recovery occurred in 72.3% of patients, associated with a 39% reduction in all-cause hospitalization compared to the non-recovered EFs in our cohort. The only independent predictor of recovered EF was E/E′ < 15 in our series.

Accelerated diastolic dysfunction in premenopausal women with rheumatoid arthritis

Background

Disturbances of diastolic function precede systolic heart failure and, although clinically silent, represent the earliest sign of cardiac involvement. Diastolic dysfunction (DD) is associated with age, gender (female), and hypertension. However, little is known about the age-specific incidence rates and risk factors for DD in patients with rheumatoid arthritis (RA).

Methods

We used standard two-dimensional/Doppler echocardiography to screen for the presence of diastolic dysfunction in 61 patients with RA and 107 healthy subjects. All participants were premenopausal women with no history of hypertension. DD includes an impaired relaxation with or without increased left ventricular (LV) filling pressures, pseudonormal filling, and restrictive filling based on parameters measured using echocardiography.

Results

The two groups were similar with respect to age (P=0.269). Patients with RA had significantly higher LV mass index, LV filling pressure, and lower E/A velocity than controls. All patients had preserved ejection fraction (EF ≥50%). DD was more common in patients with RA at 47% compared to 26% in the controls (P=0.004). Women with RA in the 30- to 49-year age range were over 3.5 times more likely to have DD than those of similar age in the control group (OR=3.54; 95% CI 1.27 to 9.85). Among patients with RA, high CRP levels were independently associated with DD even after adjustment for cardiovascular risk factors (P=0.009).

Conclusions

In premenopausal women with RA, DD is much more common and the age of onset is reduced. Early screening of myocardial function may provide an opportunity for preventing future cardiovascular disease.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13075-021-02629-1.

Determination of the increased risk of developing atrial fibrillation in fibromyalgia syndrome

INTRODUCTION

Atrial fibrillation (AF) is the leading cause of ischemic stroke and is one of the most common arrhythmias. Previous studies have shown that impaired diastolic functions, P wave dispersion (Pd), and prolonged atrial conduction times (ACT) are associated with increased incidence of atrial fibrillation (AF). The aim of this study was to evaluate diastolic functions, Pd, and ACT in fibromyalgia syndrome (FMS) patients to determine whether there is an increase in the risk of developing AF.

METHODS

The study included a total of 140 female patients (70 FMS group, 70 healthy control group). Pd was evaluated using 12 lead electrocardiography (ECG), and diastolic functions and ACT with echocardiography. The ECG and echocardiographic evaluations were performed by different cardiologists blinded to the clinical information of the subjects.

RESULTS

There was no difference between the two groups in laboratory and clinical parameters. Patients with FMS had significantly higher echocardiographic parameters of ACT known as left-sided intra-atrial (13.9 ± 5.9 vs. 8.1 ± 1.8, p < 0.001), right-sided intra-atrial (21.9 ± 8.2 vs. 10.4 ± 3.5, p < 0.001) and interatrial [40 (25-64) ms vs. 23 (14-27) ms p < 0.001] electromechanical interval (EMI) compared with the control group. Pd was significantly greater in the FMS group compared with the control group [46 (29-62) ms vs. 32 (25-37) ms, p < 0.001]. In the FMS group, there was no significant relationship of the echocardiographic parameters of ACT, Pmax and Pd with age, E/A ratio and deceleration time (DT); while all these five parameters were significantly correlated with left atrial dimension, isovolumetric relaxation time (IVRT), fibromyalgia impact questionnaire (FIQ) and visual analogue scale (VAS). There was a strong correlation between FIQ and VAS and echocardiographic parameters of ACT, Pmax and Pd.

CONCLUSIONS

Impaired diastolic functions, an increase in Pd, and prolongation of ACT were observed in FMS. Current disorders are thought to be associated with an increased risk of AF in FMS. The risk of developing AF increases with the severity of FMS and clinical progression.

Biomarkers of Inflammation in Left Ventricular Diastolic Dysfunction

Left ventricular diastolic dysfunction (LVDD) is an important precursor to many different cardiovascular diseases. Diastolic abnormalities have been studied extensively in the past decade, and it has been confirmed that one of the mechanisms leading to heart failure is a chronic, low-grade inflammatory reaction. The triggers are classical cardiovascular risk factors, grouped under the name of metabolic syndrome (MetS), or other systemic diseases that have an inflammatory substrate such as chronic obstructive pulmonary disease. The triggers could induce myocardial apoptosis and reduce ventricular wall compliance through the release of cytokines by multiple pathways such as (1) immune reaction, (2) prolonged cell hypoxemia, or (3) excessive activation of neuroendocrine and autonomic nerve function disorder. The systemic proinflammatory state causes coronary microvascular endothelial inflammation which reduces nitric oxide bioavailability, cyclic guanosine monophosphate content, and protein kinase G (PKG) activity in adjacent cardiomyocytes favoring hypertrophy development and increases resting tension. So far, it has been found that inflammatory cytokines associated with the heart failure mechanism include TNF-α, IL-6, IL-8, IL-10, IL-1α, IL-1β, IL-2, TGF-β, and IFN-γ. Some of them could be used as diagnosis biomarkers. The present review aims at discussing the inflammatory mechanisms behind diastolic dysfunction and their triggering conditions, cytokines, and possible future inflammatory biomarkers useful for diagnosis.

Evaluation of Ventricular Diastolic Function in Patients With Fibromyalgia Syndrome

Objectives

This study aims to compare the diastolic functions between fibromyalgia (FM) patients and control subjects by using transthoracic echocardiography.

Patients and methods

This case-control and cross-sectional study included 34 female FM patients (mean age 43.6±8.2 years; range 28 to 57 years), who were diagnosed by The American College of Rheumatology 1990 Criteria for the Classification of Fibromyalgia and defined as the FM group. A control group was defined consisting of 30 healthy females (mean age 41.2±9.1 years; range 22 to 54 years). Echocardiography findings of the groups were compared.

Results

The body mass index and mean disease duration of the FM group were 25.37±2.71 kg/m2 and 12.24 months, respectively. The body mass index of the control group was 25.58±1.49 kg/m2. There was no significant difference between the groups in terms of age and body mass index. Isovolumetric relaxation time and mitral E-wave deceleration time values were significantly higher in the FM group than in the control group (p=0.047, p=0.003, respectively).

Conclusion

Isovolumetric relaxation time and mitral valve deceleration time are significantly prolonged in FM patients compared with healthy subjects. Female patients with FM seem to be under risk of impaired relaxation and diastolic function of the left ventricle.

Aldosterone Receptor Blockade in Heart Failure with Preserved Ejection Fraction

More than 50% of patients with clinical heart failure have a preserved ejection fraction. Despite mortality that is similar to or slightly lower than heart failure with reduced ejection fraction, trials to date have not shown a therapy that imparts a mortality benefit in heart failure with preserved ejection fraction (HFpEF). HFpEF represents a heterogeneous disorder with a complex pathophysiologic basis, and this may contribute to the negative results in clinical trials. Geographic variations in both patient selection and adherence to study medications confound the interpretation of the trial results. Mineralocorticoid receptor antagonists may be useful in selected patients.

Echocardiographic evaluation of left ventricular diastolic dysfunction in subclinical hypothyroidism: A case-control study

PURPOSE

To study the prevalence of left ventricular diastolic dysfunction (LVDD) in patients with subclinical hypothyroidism (SCH) and the response of LVDD to L-thyroxine therapy.

MATERIALS AND METHODS

This cross-sectional case-control study with one longitudinal arm included 67 patients with SCH attending a tertiary care hospital in Uttarakhand, India, and 67 age- and sex-matched healthy controls. LVDD was assessed by 2D, pulsed-wave Doppler (PWD), continuous wave Doppler (CWD), and tissue Doppler echocardiography (TDE). Patients with LVDD received L-thyroxine therapy with reassessment for LVDD 6 months later.

RESULTS

SCH patients had a higher prevalence of LVDD than controls (13.43% versus 1.49%; p = 0.017). LVDD showed a significant association with gender (p = 0.004) and serum FT4 (p = 0.001). E velocity, E' velocity, A' velocity, iso-volumetric relaxation time (IVRT), E/A, and E'/A' ratios were significantly lower, while A velocity, deceleration time (DT), E/E' ratio, left atrial (LA) volume index, and peak tricuspid regurgitation (TR) velocity were significantly higher in cases than controls (p < 0.05 each). The E/A ratio correlated significantly with age, serum very low-density lipoprotein (VLDL), triglycerides (TG), thyroid stimulating hormone (TSH), free triiodothyronine (FT3), and high-density lipoprotein (HDL) (p < 0.05 each). E' velocity correlated significantly with age, serum total cholesterol, VLDL, and TG (p < 0.05 each), DT with serum total cholesterol (p = 0.047), and LA volume index with age (p = 0.021). Age (p = 0.016) and serum HDL (p = 0.029) were independent predictors of E/A ratio. Gender was an independent predictor for LVDD (p = 0.003). Echocardiographic indices for LVDD showed significant improvement after 6 months of L-thyroxine therapy (p < 0.05 each).

CONCLUSIONS

LVDD occurs commonly in SCH patients. It can be detected timely using echocardiography and may be reversed by L-thyroxine therapy.

Left Ventricular Diastolic Dysfunction in Ischemic Stroke: Functional and Vascular Outcomes

Background and Purpose

Left ventricular (LV) diastolic dysfunction, developed in relation to myocardial dysfunction and remodeling, is documented in 15%-25% of the population. However, its role in functional recovery and recurrent vascular events after acute ischemic stroke has not been thoroughly investigated.

Methods

In this retrospective observational study, we identified 2,827 ischemic stroke cases with adequate echocardiographic evaluations to assess LV diastolic dysfunction within 1 month after the index stroke. The peak transmitral filling velocity/mean mitral annular velocity during early diastole (E/e’) was used to estimate LV diastolic dysfunction. We divided patients into 3 groups according to E/e’ as follows: <8, 8-15, and ≥15. Recurrent vascular events and functional recovery were prospectively collected at 3 months and 1 year.

Results

Among included patients, E/e’ was 10.6±6.4: E/e’ <8 in 993 (35%), 8-15 in 1,444 (51%), and ≥15 in 378 (13%) cases. Functional dependency or death (modified Rankin Scale score ≥2) and composite vascular events were documented in 1,298 (46%) and 187 (7%) patients, respectively, at 3 months. In multivariable analyses, ischemic stroke cases with E/e’ ≥15 had increased odds of functional dependence or death at 3 months (adjusted OR [95% CI]: 1.73 [1.27-2.35]) or 1 year (1.47 [1.06-2.06]) and vascular events within 1 year (1.65 [1.08-2.51]). Subgroups with normal ejection fraction or sinus rhythm exhibited a similar overall pattern and direction.

Conclusions

LV diastolic dysfunction was associated with poor functional outcomes and composite vascular events up to 1 year.

Pre-clinical diastolic dysfunction

Pre-clinical diastolic dysfunction (PDD) has been broadly defined as left ventricular diastolic dysfunction without the diagnosis of congestive heart failure (HF) and with normal systolic function. PDD is an entity that remains poorly understood, yet has definite clinical significance. Although few original studies have focused on PDD, it has been shown that PDD is prevalent, and that there is a clear progression from PDD to symptomatic HF including dyspnea, edema, and fatigue. In diabetic patients and in patients with coronary artery disease or hypertension, it has been shown that patients with PDD have a significantly higher risk of progression to heart failure and death compared with patients without PDD. Because of these findings and the increasing prevalence of the heart failure epidemic, it is clear that an understanding of PDD is essential to decreasing patients' morbidity and mortality. This review will focus on what is known concerning pre-clinical diastolic dysfunction, including definitions, staging, epidemiology, pathophysiology, and the natural history of the disease. In addition, given the paucity of trials focused on PDD treatment, studies targeting risk factors associated with the development of PDD and therapeutic trials for heart failure with preserved ejection fraction will be reviewed.

HEART AND AGE (PART II): CLINICAL MANIFESTATIONS OF AGEING

Ageing is an inevitable process which affects quality of life and reduces life expectancy. Age-related cardiac changes reduce compensatory reserves of the heart and accelerate the disease development. Such changes in cardiac structure and function, observed in the absence of cardiovascular disease (CVD), are considered age-related. However, taking into account the high prevalence of CVD in the elderly, it is problematic to define the genuine cardiac ageing. This review discusses a range of subclinical cardiac conditions which are common in older people. 

Maternal Cardiovascular Impairment in Pregnancies Complicated by Severe Fetal Growth Restriction

Fetal growth restriction and preeclampsia are both conditions of placental etiology and associated to increased risk for the long-term development of cardiovascular disease in the mother. At presentation, preeclampsia is associated with maternal global diastolic dysfunction, which is determined, at least in part, by increased afterload and myocardial stiffness. The aim of this study is to test the hypothesis that women with normotensive fetal growth-restricted pregnancies also exhibit global diastolic dysfunction. This was a prospective case-control study conducted over a 3-year period involving 29 preterm fetal growth-restricted pregnancies, 25 preeclamptic with fetal growth restriction pregnancies, and 58 matched control pregnancies. Women were assessed by conventional echocardiography and tissue Doppler imaging at diagnosis of the complication and followed-up at 12 weeks postpartum. Fetal growth-restricted pregnancies are characterized by a lower cardiac index and higher total vascular resistance index than expected for gestation. Compared with controls, fetal growth-restricted pregnancy was associated with significantly increased prevalence ( P <0.001) of asymptomatic left ventricular diastolic dysfunction (28% versus 4%) and widespread impaired myocardial relaxation (59% versus 21%). Unlike preeclampsia, cardiac geometry and intrinsic myocardial contractility were preserved in fetal growth-restricted pregnancy. Fetal growth-restricted pregnancies are characterized by a low output, high resistance circulatory state, as well as a higher prevalence of asymptomatic global diastolic dysfunction and poor cardiac reserve. These findings may explain the increased long-term cardiovascular risk in these women who have had fetal growth-restricted pregnancies. Further studies are needed to clarify the postnatal natural history of cardiac dysfunction in these women.

The natural history of preclinical diastolic dysfunction: a population-based study

BACKGROUND

Preclinical diastolic dysfunction (PDD) has been broadly defined as subjects with left ventricular diastolic dysfunction, without the diagnosis of congestive heart failure (HF) and with normal systolic function. Our objective was to determine the risk factors associated with the progression from PDD (stage B) HF to symptomatic (stage C) HF.

METHODS AND RESULTS

Using the resources of the Rochester Epidemiology Project, all residents of Olmsted County, MN, who underwent echocardiography between January 1, 2004, and December 31, 2005, and had grade 2-4 diastolic dysfunction and ejection fraction ≥50% were identified. Patients with a diagnosis of HF before or within 30 days of the echocardiogram were excluded. Patients were also excluded if they had a diagnosis of atrial fibrillation or severe mitral or aortic valve regurgitation at the time of the echocardiogram. A total of 388 patients met the inclusion criteria. The mean age of the cohort was 67±12 years, with a female (57%) predominance. Prevalence of renal insufficiency (estimated glomerular filtration rate <60 mL/min per 1.73 m(2)) was 34%. The 3-year cumulative probabilities of development of (stage C) HF, development of atrial fibrillation, cardiac hospitalization, and mortality were 11.6%, 14.5%, 17.7%, and 10.1% respectively. In multivariable Cox proportional hazard regression analysis, we determined that age, renal dysfunction, and right ventricular systolic pressure were independently associated with the development of HF.

CONCLUSIONS

This population-based study demonstrated that in PDD (stage B) HF, there was a moderate degree of progression to symptomatic (stage C) HF over 3 years, and renal dysfunction was associated with this progression independent of age, sex, hypertension, coronary disease, and ejection fraction.

Early alterations in left ventricular diastolic function in normotensive diabetic patients

In diabetes mellitus, structural and functional alterations of the heart can be already present at the time of first diagnosis. However, how early these alterations may occur has never been fully clarified. The present study aimed at investigating cardiac functional abnormalities in uncomplicated hypertensive or normotensive patients with a recent diagnosis of diabetes mellitus. We studied 40 diabetics (24 normotensives and 16 hypertensives) by means of routine echocardiography plus pulse tissue Doppler analysis. Data were compared with those obtained in healthy age- and sex-matched controls. Left ventricular remodelling was more evident in hypertensive diabetics than in normotensive diabetics vs controls. Diastolic function was altered in diabetic patients only when detected by pulse tissue Doppler analysis and not by conventional transmitral Doppler evaluation. Normotensive patients with type 2 diabetes with little or no evidence at standard echocardiography of alterations in cardiac structure and function, already displayed an alteration in diastolic function when the evaluation was based on the tissue Doppler approach. Patients with type 2 diabetes combined to hypertension showed more evident functional cardiac alterations at echocardiography. These findings support the conclusion that cardiac abnormalities are very early phenomena in type 2 diabetes.

Progression of preclinical diastolic dysfunction to the development of symptoms

BACKGROUND

Preclinical diastolic dysfunction (PDD) has been defined as subjects with normal systolic function, diastolic dysfunction but no symptoms of heart failure (HF). The clinical phenotype and natural history of the syndrome remains poorly defined. This study's objective was to determine the clinical phenotype and progression to HF in a group of patients with normal systolic function and moderate or severe diastolic dysfunction as determinate by Doppler criteria without any clinical diagnosis of HF according to the Framingham criteria or any symptoms of HF, specifically dyspnoea, oedema or fatigue at the time of echocardiography.

METHODS

The authors used resources of the Mayo Clinic echocardiography database to consecutively select among patients who had an echocardiogram in 2005, a cohort with moderate or severe diastolic dysfunction by Doppler criteria and EF >or=50%. Patients could not have a diagnosis of HF, or any HF symptoms-specifically dyspnoea, oedema or fatigue-at the time of echocardiography; nor grade 3 or greater valvular dysfunction (except tricuspid valve). A total of 82 patients had their medical chart reviewed. Primary endpoint was the time to the development of (1) HF according to the Framingham criteria or (2) any symptoms of dyspnoea, oedema or fatigue.

RESULTS

The mean age of the cohort of PDD subjects was 69+/-10 years with a female (67%) preponderance. Presence of hypertension was 76%, coronary artery disease was 29%, paroxysmal atrial fibrillation was 26%, estimated creatinine clearance <60 ml/min was 51%. The 2-year cumulative probability of development of HF according to the Framingham criteria was 1.9%; however, the 2-year cumulative probability of development of any symptoms was 31.1%. The 2-year cumulative probability for cardiac hospitalisation was 21.2%. Peripheral vascular disease and hypertension were independently associated with increased likelihood for the development of symptoms.

CONCLUSION

The study demonstrates that hypertension, hyperlipidaemia, CAD and renal dysfunction are prevalent in patients with PDD. More importantly, although the progression to the development of clinical HF over 2 years was low, there was a moderate degree of progression to development of symptoms and cardiac hospitalisations over 2 years. Based on the finding that only PVD and hypertension were independently associated with the progression to the development of symptoms in subject with PDD, the authors speculate that ventricular-arterial interaction may be important to the progression of diastolic dysfunction to the development of symptoms.

Exercise training during diabetes attenuates cardiac ryanodine receptor dysregulation

The present study was undertaken to assess the effects of exercise training (ExT) initiated after the onset of diabetes on cardiac ryanodine receptor expression and function. Type 1 diabetes was induced in male Sprague-Dawley rats using streptozotocin (STZ). Three weeks after STZ injection, diabetic rats were divided into two groups. One group underwent ExT for 4 wk while the other group remained sedentary. After 7 wk of sedentary diabetes, cardiac fractional shortening, rate of rise of left ventricular pressure, and myocyte contractile velocity were reduced by 14, 36, 44%, respectively. Spontaneous Ca(2+) spark frequency increased threefold, and evoked Ca(2+) release was dyssynchronous with diastolic Ca(2+) releases. Steady-state type 2 ryanodine receptor (RyR2) protein did not change, but its response to Ca(2+) was altered. RyR2 also exhibited 1.8- and 1.5-fold increases in phosphorylation at Ser(2808) and Ser(2814). PKA activity was reduced by 75%, but CaMKII activity was increased by 50%. Four weeks of ExT initiated 3 wk after the onset of diabetes blunted decreases in cardiac fractional shortening and rate of left ventricular pressure development, increased the responsiveness of the myocardium to isoproterenol stimulation, attenuated the increase in Ca(2+) spark frequency, and minimized dyssynchronous and diastolic Ca(2+) releases. ExT also normalized the responsiveness of RyR2 to Ca(2+) activation, attenuated increases in RyR2 phosphorylation at Ser(2808) and Ser(2814), and normalized CaMKII and PKA activities. These data are the first to show that ExT during diabetes normalizes RyR2 function and Ca(2+) release from the sarcoplasmic reticulum, providing insights into mechanisms by which ExT during diabetes improves cardiac function.

The clinical significance of subclinical thyroid dysfunction

Subclinical thyroid disease (SCTD) is defined as serum free T(4) and free T(3) levels within their respective reference ranges in the presence of abnormal serum TSH levels. SCTD is being diagnosed more frequently in clinical practice in young and middle-aged people as well as in the elderly. However, the clinical significance of subclinical thyroid dysfunction is much debated. Subclinical hyper- and hypothyroidism can have repercussions on the cardiovascular system and bone, as well as on other organs and systems. However, the treatment and management of SCTD and population screening are controversial despite the potential risk of progression to overt disease, and there is no consensus on the thyroid hormone and thyrotropin cutoff values at which treatment should be contemplated. Opinions differ regarding tissue effects, symptoms, signs, and cardiovascular risk. Here, we critically review the data on the prevalence and progression of SCTD, its tissue effects, and its prognostic implications. We also examine the mechanisms underlying tissue alterations in SCTD and the effects of replacement therapy on progression and tissue parameters. Lastly, we address the issue of the need to treat slight thyroid hormone deficiency or excess in relation to the patient's age.