Elevated myocardial and lymphocyte GRK2 expression and activity in human heart failure.

The G protein-coupled receptor kinase-2 (GRK2 or beta-ARK1) regulates beta-adrenergic receptors (beta-ARs) in the heart, and its cardiac expression is elevated in human heart failure (HF). We sought to determine whether myocardial levels and activity of GRK2 could be monitored using white blood cells, which have been used to study cardiac beta-ARs. Moreover, we were interested in determining whether GRK2 levels in myocardium and lymphocytes may be associated with beta-AR dysfunction and HF severity.In myocardial biopsies from explanted failing human hearts, GRK activity was inversely correlated with beta-AR-mediated cAMP production (R(2)=-0.215, P<0.05, n=24). Multiple regression analysis confirmed that GRK activity participates with beta-AR density to regulate catecholamine-sensitive cAMP responses. Importantly, there was a direct correlation between myocardial and lymphocytes GRK2 activity (R(2)=0.5686, P<0.05, n=10). Lymphocyte GRK activity was assessed in HF patients with various ejection fractions (EFs) (n=33), and kinase activity was significantly higher in patients with lower EFs and was higher with increasing NYHA class (P<0.001).Myocardial GRK2 expression and activity are mirrored by lymphocyte levels of this kinase, and its elevation in HF is associated with the loss of beta-AR responsiveness and appears to increase with disease severity. Therefore, lymphocytes may provide a surrogate for monitoring cardiac GRK2 in human HF

Epicardial Adipose Tissue and Postoperative Atrial Fibrillation

Background: Atrial fibrillation (AF) often occurs after cardiac surgery and is associated with increased risk of stroke and mortality. Prior studies support the important role of inflammation in the pathogenesis of postoperative atrial fibrillation (POAF). It is known that an increased volume and a pro-inflammatory phenotype of epicardial adipose tissue (EAT) are both associated with AF onset in non surgical context. In the present study, we aim to evaluate whether also POAF occurrence may be triggered by an increased production of inflammatory mediators from EAT. Methods: The study population was composed of 105 patients, with no history of paroxysmal or permanent AF, undergoing elective cardiac surgery. After clinical evaluation, all patients performed an echocardiographic study including the measurement of EAT thickness. Serum samples and EAT biopsies were collected before surgery. Levels of 10 inflammatory cytokines were measured in serum and EAT conditioned media. After surgery, cardiac rhythm was monitored for 7 days. Results: Forty-four patients (41.3%) developed POAF. As regard to cardiovascular therapy, only statin use was significantly lower in POAF patients (65.1% vs. 84.7%; p-0.032). Levels of Monocyte Chemoattractant Protein-1 (MCP-1), in both serum and EAT, were significantly higher in POAF patients (130.1 pg/ml vs. 68.7 pg/ml; p = &lt;0.001; 322.4 pg/ml vs. 153.4 pg/ml; p = 0.028 respectively). EAT levels of IL-6 were significantly increased in POAF patients compared to those in sinus rhythm (SR) (126.3 pg/ml vs. 23 pg/ml; p = &lt; 0.005). Conclusion: Higher EAT levels of IL-6 and MCP-1 are significantly associated with the occurrence of POAF. Statin therapy seems to play a role in preventing POAF. These results might pave the way for a targeted use of these drugs in the perioperative period

Epicardial Adipose Tissue and IL-13 Response to Myocardial Injury Drives Left Ventricular Remodeling After ST Elevation Myocardial Infarction

Introduction: Left ventricular (LV) remodeling after ST-segment elevation myocardial infarction (STEMI) is explained only in part by the infarct size, and the inter-patient variability may be ascribed to different inflammatory response to myocardial injury. Epicardial adipose tissue (EAT) is a source of inflammatory mediators which directly modulates the myocardium. EAT increase is associated to several cardiovascular diseases; however, its response to myocardial injury is currently unknown. Among inflammatory mediators, IL-13 seems to play protective role in LV regeneration, but its variations after STEMI have not been described yet. Purpose: In the present study we analyzed the association between infarct-related changes of EAT and IL-13 in post-STEMI LV remodeling. Methods: We enrolled 100 patients with STEMI undergoing primary angioplasty. At the enrolment (T0) and after 3 months (T1), we measured EAT thickness by echocardiography and circulating levels of IL-13 by ELISA. Results: At T1, the 60% of patients displayed increased EAT thickness (ΔEAT &gt; 0). ΔEAT was directly associated to LV end-diastolic volume (r = 0.42; p = 0.014), LV end-systolic volume (r = 0.42; p = 0.013) and worse LV ejection fraction (LVEF) at T1 (r = −0.44; p = 0.0094), independently of the infarct size. In the overall population IL-13 levels significantly decreased at T1 (p = 0.0002). The ΔIL-13 was directly associated to ΔLVEF (r = 0.42; p = 0.017) and inversely related to ΔEAT (r = −0.51; p = 0.022), thus suggesting a protective role for IL-13. Conclusion: The variability of STEMI-induced “inflammatory response” may be associated to the post-infarct LV remodeling. ΔEAT thickness and ΔIL-13 levels could be novel prognostic markers in STEMI patients

Exercise promotes angiogenesis and improves beta-adrenergic receptor signalling in the post-ischaemic failing rat heart.

We investigated whether exercise training could promote angiogenesis and improve blood perfusion and left ventricular (LV) remodelling of the post-myocardial infarction (MI) failing heart. We also explored the contribution of ameliorated beta-adrenergic receptor signalling and function on the overall improvement of cardiac contractility reserve induced by exercise.Adult Wistar male rats were randomly assigned to one of four experimental groups. Sham-operated and post-MI heart failure (HF) rats were housed under sedentary conditions or assigned to 10-weeks of a treadmill exercise protocol. At 4 weeks after MI, sedentary HF rats showed LV eccentric hypertrophy, marked increase of LV diameters associated with severely impaired fractional shortening (14 +/- 5\%), increased LV end diastolic pressure (20.9 +/- 2.6 mmHg), and pulmonary congestion. In addition, cardiac contractile responses to adrenergic stimulation were significantly blunted. In trained HF rats, exercise was able to (i) reactivate the cardiac vascular endothelial growth factor pathway with a concurrent enhancement of myocardial angiogenesis, (ii) significantly increase myocardial perfusion and coronary reserve, (iii) reduce cardiac diameters, and (iv) improve LV contractility in response to adrenergic stimulation. This latter finding was also associated with a significant improvement of cardiac beta-adrenergic receptor downregulation and desensitization.Our data indicate that exercise favourably affects angiogenesis and improves LV remodelling and contractility reserve in a rat model of severe chronic HF

ITACARE-P/SIGG/SIGOT/SICGE position paper on elderly cardiac patient referral to cardiac rehabilitation

The Italian Association for Cardiovascular Rehabilitation and Prevention (ITACARE-P) together with the Società Italiana di Gerontologia e Geriatria (SIGG); Società Italiana di Geriatria Ospedale e Territorio (SIGOT); SICGE, Società Italiana di Cardiologia Geriatrica (SICGE) released a joint position paper to guide referrals of elderly cardiovascular patients discharged from Geriatric wards to Cardiac Rehabilitation (CR) facilities. The document provides rationale and operative recommendations for appropriateness (i.e. qualifying diagnosis) and priority criteria to overcome mismatch between potential demand and effective supply of CR programmes. In case of no-referral due to logistic restraints, the document recommends the adoption of best alternatives to CR for disability reduction, better prognosis, and improvement of quality of life. The joint position paper is also aimed at promoting the consideration of Geriatric Medicine as a potential stakeholder of CR