Effects of Hormonal Anabolic Deficiency and Neurovascular Alterations on Mortality in Male Patients With Heart Failure
Condition: Heart Failure
MeSH terms: Heart Failure
Study type: Observational

Summary: 
      Heart failure (HF) has been associated with chronic deleterious effects on skeletal muscle,
      endocrine system, vasculature and sympathetic nervous system. These alterations have a
      significant impact on quality of life, leading to a reduction in functional capacity and
      limited symptoms, which involve dyspnea and fatigue. The investigators tested the hypothesis
      that hormonal anabolic deficiency associated with neurovascular alterations may worsen the
      prognosis of patients with heart failure.
    

Detailed description: 
      One hundred and fifty six patients have been enrolled so far. Methods were as described
      below:

        -  Muscle sympathetic nerve activity (MSNA) was directly recorded from the peroneal nerve
           using the microneurography technique ;

        -  All patients underwent symptom-limited cardiopulmonary exercise test performed on a
           cycle ergometer, using a ramp protocol with workload increments of 5 or 10 Watts per
           minute;

        -  Body composition measurements were performed using dual-energy X-ray absorptiometry
           (DXA);

        -  Muscle strength was assessed by handgrip dynamometer using the mean value of three
           attempts;

        -  Blood samples were drawn in the morning after 12h overnight fasting. The laboratory
           tests included B-type natriuretic peptide (BNP; pg/mL) plasma level, serum sodium
           (mEq/L), serum potassium (mEq/L), creatinine (mg/dL), haemoglobin level (g/dL),
           high-sensitivity C-reactive protein (CRP; mg/L), lipid profile (triglyceride, total
           cholesterol, high-density lipoprotein, and low-density lipoprotein; mg/dL), and fasting
           glucose (mg/dL). Blood sample to assess hormone plasma levels were also drawn at the
           same time: total testosterone (TT), free testosterone (FT), sex hormone binding globulin
           (SHBG), dehydroepiandrosterone sulfate (DHEAS), luteinizing hormone (LH),
           follicle-stimulating hormone (FSH), thyroid stimulating hormone (TSH) and insulin-like
           growth factor 1 (IGF1).
    

Intervention name(s): Cardiopulmonary exercise test; Muscle Sympathetic Nerve Activity; Dual-energy X-ray absorptiometry; Venous occlusion plethysmography; Blood sample collection; Dynamometers for Handgrip Strength
Intervention type(s): Diagnostic Test; Diagnostic Test; Diagnostic Test; Diagnostic Test; Diagnostic Test; Diagnostic Test
Intervention description(s): Oxygen consumption (VO2) and carbon dioxide output (VCO2) were measured by means of gas exchange on a breath-by-breath basis. The patients were initially monitored for 2 minutes at rest when seated on the ergometer, after that they were instructed to pedal at a pace of 60-70 rpm and the completion of the test occurred when, in spite of verbal encouragement, the patient reached maximal volitional fatigue.; Multiunit post-ganglionic muscle sympathetic nerve recordings were made using a tungsten microelectrode placed in the peroneal nerve near the fibular head. Nerve signals were amplified by a factor of 50,000 to 100,000 and band-pass filtered (700 to 2000 Hz). For recording and analysis, nerve activity was rectified and integrated (time constant 0.1 seconds) to obtain a mean voltage display of sympathetic nerve activity.; Dual-energy X-ray absorptiometry (DXA) scan was used to measure total lean mass, body fat and bone mineral content.; Venous occlusion plethysmography was used to assess non-invasively blood flow.; Blood samples were drawn in the morning after 12h overnight fasting.; Muscle strength was assessed by handgrip dynamometer using the mean value of three attempts.
Observational model: Cohort
Time perspective: Prospective
Sampling method: Probability Sample
Study population: 
        Patients with heart failure recruited at Clinical Unit of Myocardiopathy at General
        Hospital of the University of São Paulo Medical School (UNCAR/HC-FMUSP).
      
Keywords: Testosterone Deficiency; Sympathetic overactivity; Exercise Intolerance