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Concept: Ejection fraction

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Background -Current guidelines only recommend the use of an implantable cardioverter defibrillator (ICD) in patients with dilated cardiomyopathy (DCM) for the primary prevention of sudden cardiac death (SCD) in those with a left ventricular ejection fraction (LVEF)<35%. However, registries of out-of-hospital cardiac arrests demonstrate that 70-80% of such patients have a LVEF>35%. Patients with a LVEF>35% also have low competing risks of death from non-sudden causes. Therefore, those at high-risk of SCD may gain longevity from successful ICD therapy. We investigated whether late gadolinium enhancement cardiovascular magnetic resonance (LGE-CMR) identified patients with DCM without severe LV systolic dysfunction at high-risk of SCD. Methods -We prospectively investigated the association between mid-wall late gadolinium enhancement (LGE) and the pre-specified primary composite outcome of SCD or aborted SCD amongst consecutive referrals with DCM and a LVEF≥40% to our center between January 2000 and December 2011, who did not have a pre-existing indication for ICD implantation. Results -Of 399 patients (145 women, median age 50 years, median LVEF 50%, 25.3% with LGE) followed for a median of 4.6 years, 18 of 101 (17.8%) patients with LGE reached the pre-specified end-point, compared to 7 of 298 (2.3%) without (HR 9.2; 95% CI 3.9-21.8; p<0.0001). Nine patients (8.9%) with LGE compared to 6 (2.0%) without (HR 4.9; 95% CI 1.8-13.5; p=0.002) died suddenly, whilst 10 patients (9.9%) with LGE compared to 1 patient (0.3%) without (HR 34.8; 95% CI 4.6-266.6; p<0.001) had aborted SCD. Following adjustment, LGE predicted the composite end-point (HR 9.3; 95% CI 3.9-22.3; p<0.0001), SCD (HR 4.8; 95% CI 1.7-13.8; p=0.003) and aborted SCD (HR 35.9; 95% CI 4.8-271.4; p<0.001). Estimated hazard ratios for the primary end-point for patients with a LGE extent of 0-2.5%, 2.5-5% and >5% compared to those without LGE were 10.6 (95%CI 3.9-29.4), 4.9 (95% CI 1.3-18.9) and 11.8 (95% CI 4.3-32.3) respectively. Conclusions -Mid-wall LGE identifies a group of patients with DCM and LVEF≥40% at increased risk of SCD and low-risk of non-sudden death who may benefit from ICD implantation. Clinical Trial Registration -https://clinicaltrials.gov/ Identifier: NCT00930735.

Concepts: Myocardial infarction, Cardiology, Heart failure, Ejection fraction, Implantable cardioverter-defibrillator, Cardiac arrest, Ventricular fibrillation, Sudden cardiac death

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Increased sympathetic and decreased parasympathetic activity contribute to heart failure (HF) symptoms and disease progression. Carotid baroreceptor stimulation (baroreflex activation therapy; BAT) results in centrally mediated reduction of sympathetic and increase in parasympathetic activity. Because patients treated with cardiac resynchronization therapy (CRT) may have less sympathetic / parasympathetic imbalance, we hypothesized that there would be differences in the response to BAT in patients with CRT versus those without CRT.

Concepts: Myocardial infarction, Cardiology, Heart failure, Ejection fraction, Heart, Mammal, Autonomic nervous system, Sinoatrial node

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Background: Conventional cardiac rehabilitation program consist of 15 min of warm-up, 30 min of aerobic exercise and followed by 15 min calisthenics exercise. The Pilates method has been increasingly applied for its therapeutic benefits, however little scientific evidence supports or rebukes its use as a treatment in patients with heart failure (HF). Purpose: Investigate the effects of Pilates on exercise capacity variables in HF. Methods: Sixteen pts with HF, left ventricular ejection fraction 27 ± 14%, NYHA class I-II were randomly assigned to conventional cardiac rehabilitation program (n = 8) or mat Pilates training (n = 8) for 16 weeks of 30 min of aerobic exercise followed by 20 min of the specific program. Results: At 16 weeks, pts in the mat Pilates group and conventional group showed significantly increase on exercise time 11.9 ± 2.5 to 17.8 ± 4 and 11.7 ± 3.9 to 14.2 ± 4 min, respectively. However, only the Pilates group increased significantly the ventilation (from 56 ± 20 to 69 ± 17 L/min, P= 0.02), peak VO(2) (from 20.9 ± 6 to 24.8 ± 6 mL/kg/min, P= 0.01), and O(2) pulse (from 11.9 ± 2 to 13.8 ± 3 mL/bpm, P= 0.003). The Pilates group showed significantly increase in peak VO(2) when compared with conventional group (24.8 ± 6 vs. 18.3 ± 4, P= 0.02). Conclusions: The result suggests that the Pilates method may be a beneficial adjunctive treatment that enhances functional capacity in patients with HF who are already receiving standard medical therapy.

Concepts: Blood, Myocardial infarction, Cardiology, Heart failure, Ejection fraction, Heart, Strength training, 5BX

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Aldosterone antagonist therapy for heart failure and reduced ejection fraction has been highly efficacious in randomized trials. However, questions remain regarding the effectiveness and safety of the therapy in clinical practice.

Concepts: Clinical trial, Myocardial infarction, Cardiology, Heart failure, Ejection fraction, Randomized controlled trial, Effectiveness, Aldosterone antagonist

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CONTEXT While the delivery of cell therapy after ST-segment elevation myocardial infarction (STEMI) has been evaluated in previous clinical trials, the influence of the timing of cell delivery on the effect on left ventricular function has not been analyzed. OBJECTIVES To determine the effect of intracoronary autologous bone marrow mononuclear cell (BMC) delivery after STEMI on recovery of global and regional left ventricular function and whether timing of BMC delivery (3 days vs 7 days after reperfusion) influences this effect. DESIGN, SETTING, AND PATIENTS A randomized, 2 × 2 factorial, double-blind, placebo-controlled trial, Timing In Myocardial infarction Evaluation (TIME) enrolled 120 patients with left ventricular dysfunction (left ventricular ejection fraction [LVEF] ≤ 45%) after successful primary percutaneous coronary intervention (PCI) of anterior STEMI between July 17, 2008, and November 15, 2011, as part of the Cardiovascular Cell Therapy Research Network sponsored by the National Heart, Lung, and Blood Institute. INTERVENTIONS Intracoronary infusion of 150 × 106 BMCs or placebo (randomized 2:1) within 12 hours of aspiration and cell processing administered at day 3 or day 7 (randomized 1:1) after treatment with PCI. MAIN OUTCOME MEASURES The primary end points were change in global (LVEF) and regional (wall motion) left ventricular function in infarct and border zones at 6 months measured by cardiac magnetic resonance imaging and change in left ventricular function as affected by timing of treatment on day 3 vs day 7. The secondary end points included major adverse cardiovascular events as well as changes in left ventricular volumes and infarct size. RESULTS The mean (SD) patient age was 56.9 (10.9) years and 87.5% of participants were male. At 6 months, there was no significant increase in LVEF for the BMC group (45.2% [95% CI, 42.8% to 47.6%] to 48.3% [95% CI, 45.3% to 51.3%) vs the placebo group (44.5% [95% CI, 41.0% to 48.0%] to 47.8% [95% CI, 43.4% to 52.2%]) (P = .96). There was no significant treatment effect on regional left ventricular function observed in either infarct or border zones. There were no significant differences in change in global left ventricular function for patients treated at day 3 (-0.9% [95% CI, -6.6% to 4.9%], P = .76) or day 7 (1.1% [95% CI, -4.7% to 6.9%], P = .70). The timing of treatment had no significant effect on regional left ventricular function recovery. Major adverse events were rare among all treatment groups. CONCLUSION Among patients with STEMI treated with primary PCI, the administration of intracoronary BMCs at either 3 days or 7 days after the event had no significant effect on recovery of global or regional left ventricular function compared with placebo. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00684021.

Concepts: Clinical trial, Myocardial infarction, Atherosclerosis, Cardiology, Heart failure, Ejection fraction, Heart, Percutaneous coronary intervention

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Heart failure (HF) is associated with significant morbidity and mortality. Although initially thought to be harmful in HF, beta-adrenergic blockers (β-blockers) have consistently been shown to reduce mortality and HF hospitalization in chronic HF with reduced ejection fraction. Proposed mechanisms include neurohormonal blockade and heart rate reduction. A new therapeutic agent now exists to target further heart rate lowering in patients who have been stable on a “maximally tolerated β-blocker dose,” but this definition and how to achieve it are incompletely understood. In this review, the authors summarize published reports on the mechanisms by which β-blockers improve clinical outcomes. The authors describe differences in doses achieved in landmark clinical trials and those observed in routine clinical practice. They further discuss reasons for intolerance and the evidence behind using β-blocker dose and heart rate as therapeutic targets. Finally, the authors offer recommendations for clinicians actively initiating and up-titrating β-blockers that may aid in achieving maximally tolerated doses.

Concepts: Clinical trial, Myocardial infarction, Hospital, Cardiology, Heart failure, Ejection fraction, Avicenna, Beta blocker

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The neural cardiac therapy for heart failure (NECTAR-HF) was a randomized sham-controlled trial designed to evaluate whether a single dose of vagal nerve stimulation (VNS) would attenuate cardiac remodelling, improve cardiac function and increase exercise capacity in symptomatic heart failure patients with severe left ventricular (LV) systolic dysfunction despite guideline recommended medical therapy.

Concepts: Medicine, Cardiology, Heart failure, Ejection fraction, Randomized controlled trial, Muscle, Vagus nerve, Vagus nerve stimulation

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The aim of this study was to identify the best echocardiographic method for sequential quantification of left ventricular (LV) ejection fraction (EF) and volumes in patients undergoing cancer chemotherapy.

Concepts: Cancer, Cardiology, Ejection fraction, Echocardiography, Chemotherapy

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Ejection fraction (EF) is the most widely used instrumental parameter in clinical cardiology for the evaluation of left ventricular systolic function and prognostic stratification of various cardiac diseases, including ischemic heart disease and heart failure. EF has some advantages but also many limitations, which may favor an incorrect use of this parameter. Moreover, the different cardiac imaging techniques available for EF calculation can be an additional source of errors and inaccuracies. This article will review in detail the pathophysiological features and intrinsic limitations of EF, with the aim to clarify how to properly use this parameter.

Concepts: Myocardial infarction, Cardiology, Heart failure, Ejection fraction, Heart, Echocardiography, Heart disease, Ischaemic heart disease

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Background: Exercise capacity is critical for therapy and prognosis in patients with heart failure (HF). Effect of beta-blockers (BB) on exercise capacity in elderly patients with HF remains unclear. Objectives: To assess contribution of BB to functional capacity and left ventricular (LV) function in the elderly with HF. Design: According to the protocol of CIBISELD study group, elderly patients were treated with BB during 12 weeks. In CPET subgroup, an integral part of the CIBIS ELD study group, patients were performed Doppler echocardiography and cardiopulmonary exercise testing (CPET) before BB therapy and after 12 weeks. Setting: Randomized patients with HF beta blockers naïve. Participants: Thirty patients with HF aged over 65 years were included in CPET subgroup, while 847 incorporated in CIBIS ELD study group. Results: Heart rate (HR) and systolic blood pressure (SBP) after BB significantly decreased at rest (p < 0.001) and during exercise (p< 0.05), with sustained level of peak VO2. Observed changes of resting HR and peak HR were closely correlated (p < 0.001). Significant improvement of LV ejection fraction after BB was obtained (p= 0.003) and symptoms of breathlessness were reduced (p= 0.001). Left ventricular diastolic dysfunction at rest significantly contributed to exercise capacity (p = 0.019). Conclusions: Beta-blockers in elderly patients with HF are related to a significant decrease of HR and SBP, improvement of systolic LV function and sustained exercise tolerance. Resting LV diastolic dysfunction is strongly associated with lower exercise capacity.

Concepts: Myocardial infarction, Hypertension, Cardiology, Ejection fraction, Echocardiography, Blood pressure, Ventricle, Hypotension