Chronic heart failure is a prevalent condition in the United States, with an estimated 6.2 million adults affected by this disease. Heart failure with preserved ejection fraction (HFpEF) is a specific subtype of heart failure where the heart's ejection fraction is normal, but the heart muscle does not relax properly. Patients with HFpEF have a reduced exercise capacity and a poor quality of life. A clinical trial has shown promising results for a potential treatment option for patients with HFpEF.
The trial aimed to investigate the effect of low-level transcutaneous vagus nerve stimulation on cardiac function, exercise capacity, and inflammation in patients with HFpEF. The study was a randomized, double-blind, sham-controlled clinical trial involving 52 patients with HFpEF and at least two other comorbidities, such as obesity, diabetes, hypertension, or age ≥65 years. The patients were randomly assigned to either active or sham low-level transcutaneous vagus nerve stimulation for one hour daily for three months.
The clinical trial found that low-level transcutaneous vagus nerve stimulation improved heart function, exercise capacity, and inflammation in people with heart failure with preserved ejection fraction (HFpEF). The study involved patients with HFpEF who also had at least two other conditions such as obesity, diabetes, hypertension, or age ≥65 years.
The patients were randomly assigned to receive either active or sham stimulation for one hour daily for three months. The study was double-blind, meaning neither the researchers nor the patients knew which group they were in.
The results of the trial showed that those who received active stimulation had a significant improvement in their heart function, inflammation, and quality of life compared to those who received sham stimulation. The improvement was measured using a test called global longitudinal strain, which improved significantly in the active group (-18.6%±2.5% versus -16.0%±2.4%, P=0.002).
Additionally, the levels of an inflammatory marker called tumor necrosis factor-α were reduced in the active group (8.9±2.8 pg/mL versus 11.3±2.9 pg/mL, P=0.007). The improvement in global longitudinal strain was associated with the reduction in tumor necrosis factor-α levels (r=-0.73, P=0.001). Patients who received active stimulation also reported a better quality of life.
The trial showed that using low-level transcutaneous vagus nerve stimulation is a safe and non-invasive treatment option for patients with HFpEF. Patients tolerated the treatment well, with more than 90% of them following the daily stimulation protocol. Also, no side effects related to the device were observed, making it a promising option for patients with HFpEF.
The study's findings also suggest that a systemic proinflammatory state plays a crucial role in the development of HFpEF. Inflammation is associated with the pathogenesis of HFpEF, and the results of this trial suggest that low-level transcutaneous vagus nerve stimulation may suppress inflammation in patients with HFpEF.