Transcutaneous Electrical Nerve Stimulation and Cardiac Sympathetic Overdrive in Heart Failure
Condition: Cardiovascular Abnormalities
MeSH terms: Heart Failure; Cardiovascular Abnormalities
Study type: Observational

Summary: 
      Introduction: Cardiac sympathetic drive provides inotropic support to the failing heart and
      preserves cardiovascular homeostasis. Nonetheless, as myocardial insult evolves, this
      compensatory response leads to a progressive decline in contractile function, increases the
      vulnerability to arrhythmias and constitutes an independent mortality predictor. Despite
      advanced pharmacological therapies, side effects and persistent cardiac sympathetic overdrive
      highlights the modulation of the adrenergic system as a primary target for
      non-pharmacological strategies in the heart failure (HF) treatment. In this scenario, we will
      propose cervicothoracic transcutaneous electrical nerve stimulation (TENS) as a
      non-pharmacological therapy to attenuate cardiac sympathetic overdrive in patients with heart
      failure. Methods: In this prospective, randomized, sham-controlled, double-blind crossover
      trial, ten (10) HF patients under optimal pharmacological treatment will be randomly assigned
      to either an in-home cervicothoracic transcutaneous electrical nerve stimulation therapy
      (TENS: 30 min twice a day with 80 Hz frequency and pulse duration of 150 μs) or a sham
      control intervention (SHCI) for two weeks. Following a two-month washout phase from
      TENS/SHCI, patients crossed over and started the opposite condition. Washout rate and
      heart-to-mediastinum ratio (planar 123l-metaiodobenzylguanidine myocardial scintigraphy
      images), indexes of cardiac sympathetic activity and innervation density, muscle sympathetic
      nerve activity (microneurography) and brachial artery blood flow (Doppler ultrasound) during
      dynamic handgrip exercise will be obtained at the beginning and end of each condition.
    

Detailed description: 
      Introduction: Cardiac sympathetic drive provides inotropic support to the failing heart and
      preserves cardiovascular homeostasis. Nonetheless, as myocardial insult evolves, this
      compensatory response leads to a progressive decline in contractile function, increases the
      vulnerability to arrhythmias and constitutes an independent mortality predictor. Despite
      advanced pharmacological therapies, side effects and persistent cardiac sympathetic overdrive
      highlights the modulation of the adrenergic system as a primary target for
      non-pharmacological strategies in the heart failure (HF) treatment. In this scenario, we will
      propose cervicothoracic transcutaneous electrical nerve stimulation (TENS) as a
      non-pharmacological therapy to attenuate cardiac sympathetic overdrive in patients with heart
      failure. Methods: In this prospective, randomized, sham-controlled, double-blind crossover
      trial, ten (10) HF patients under optimal pharmacological treatment will be randomly assigned
      to either an in-home cervicothoracic transcutaneous electrical nerve stimulation therapy
      (TENS: 30 min twice a day with 80 Hz frequency and pulse duration of 150 μs) or a sham
      control intervention (SHCI) for two weeks. Following a two-month washout phase from
      TENS/SHCI, patients crossed over and started the opposite condition. Washout rate and
      heart-to-mediastinum ratio (planar 123l-metaiodobenzylguanidine myocardial scintigraphy
      images), indexes of cardiac sympathetic activity and innervation density, muscle sympathetic
      nerve activity (microneurography) and brachial artery blood flow (Doppler ultrasound) during
      dynamic handgrip exercise will be obtained at the beginning and end of each condition.
    

Intervention name(s): Scintigraphy
Intervention type(s): Radiation
Intervention description(s): Scintigraphy
Observational model: Cohort
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        Patients with heart failure