Effects of Diaphragmatic and Abdominal Neuromuscular Electrical Stimulation in Post-PCI Patients

Official title

Effects of Diaphragmatic and Abdominal Neuromuscular Electrical Stimulation on Arterial Blood Gases, Pulmonary Function, Ejection Fraction and Functional Capacity in Post-PCI Patients

Overview

This study is a randomized controlled trial designed to evaluate the effects of combined diaphragmatic and abdominal neuromuscular electrical stimulation (NMES) on arterial blood gases, pulmonary function, left ventricular ejection fraction, and functional capacity in patients following percutaneous coronary intervention (PCI). A total of 42 participants will be randomly allocated into two groups: an intervention group receiving NMES along with standard cardiac rehabilitation, and a control group receiving standard rehabilitation alone. The intervention will be administered for 30 minutes per session, five days per week, over a period of two weeks. Outcome measures will include arterial blood gas parameters (PaO₂, PaCO₂, SaO₂), spirometry indices (FVC, FEV₁, PEFR), ejection fraction assessed by echocardiography, and functional capacity measured using the 6-minute walk test. Assessments will be conducted at baseline and post-intervention. The study aims to determine whether NMES can serve as an effective adjunct to conventional cardiac rehabilitation in improving respiratory and functional outcomes in post-PCI patients.

Detailed description

Percutaneous coronary intervention (PCI) improves coronary blood flow in patients with coronary artery disease; however, many patients continue to experience reduced pulmonary function, impaired gas exchange, decreased cardiac performance, and limited functional capacity after the procedure. These issues are often related to respiratory muscle weakness, immobilization, and altered ventilatory mechanics. Conventional cardiac rehabilitation focuses mainly on aerobic and resistance training, with limited emphasis on respiratory muscle strengthening.

Neuromuscular electrical stimulation (NMES) is a non-invasive technique that induces muscle contractions and may enhance both inspiratory and expiratory muscle function when applied to the diaphragm and abdominal muscles. This study aims to evaluate the effectiveness of combined diaphragmatic and abdominal NMES as an adjunct to standard cardiac rehabilitation in post-PCI patients.

In this randomized controlled trial, 42 hemodynamically stable patients aged 40-75 years will be randomly assigned to either an intervention group (NMES plus standard rehabilitation) or a control group (standard rehabilitation alone). The NMES intervention will be applied for 30 minutes per session, five days per week, for two weeks.

Outcome measures will include arterial blood gases (PaO₂, PaCO₂, SaO₂), pulmonary function (FVC, FEV₁, PEFR), left ventricular ejection fraction, and functional capacity assessed by the 6-minute walk test. Assessments will be conducted at baseline and after the intervention.

This study aims to determine whether NMES can improve respiratory and functional outcomes and serve as an effective adjunct to conventional cardiac rehabilitation in post-PCI patients.

Interventions

• Device Neuromuscular Electrical Stimulation (NMES)
  A dual-channel electrical stimulation device will be used to deliver stimulation to respiratory muscles. Surface electrodes will be placed over the lower thoracic region for diaphragmatic stimulation and over the abdominal muscles for expiratory muscle stimulation. Stimulation parameters will include a frequency of 30-50 Hz, pulse width of 300 µs, and a duty cycle of 5 seconds on and 5 seconds off. Intensity will be adjusted to achieve visible muscle contraction without discomfort. Sessions will
• Other Standard Cardiac Rehabilitation
  A structured cardiac rehabilitation program including aerobic exercise, breathing exercises, and patient education delivered according to institutional protocols, without the use of neuromuscular electrical stimulation.

Primary outcome measures

• Partial Pressure of Oxygen (PaO₂) [Time frame: Baseline and after 2 weeks of intervention]
• Partial Pressure of Carbon Dioxide (PaCO₂) [Time frame: Baseline and after 2 weeks of intervention]
• Arterial Oxygen Saturation (SaO₂) [Time frame: Baseline and after 2 weeks of intervention]
• Forced Vital Capacity (FVC) [Time frame: Baseline and after 2 weeks of intervention]
• Forced Expiratory Volume in 1 Second (FEV₁) [Time frame: Baseline and after 2 weeks of intervention]
• Peak Expiratory Flow Rate (PEFR) [Time frame: Baseline and after 2 weeks of intervention]

Secondary outcome measures (1)

• Left Ventricular Ejection Fraction (LVEF) [Time frame: Baseline and after 2 weeks]

Eligibility criteria

Inclusion criteria

• Patients aged 40-75 years
• Patients who have undergone successful percutaneous coronary intervention (PCI) for stable or acute coronary syndrome
• Hemodynamically stable (no inotropic support, no active arrhythmias)
• Left ventricular ejection fraction (LVEF) ≥ 35%
• Able to perform spirometry and 6-minute walk test (6MWT)
• Willing to participate and provide informed consent

Exclusion criteria

• Significant arrhythmias or pacemaker/implantable defibrillator not cleared for NMES
• Severe pulmonary disease (e.g., advanced COPD, pulmonary fibrosis) affecting lung function independently
• Neuromuscular disorders interfering with NMES application
• Recent stroke or severe cognitive impairment limiting participation
• Active infection, sepsis, or systemic inflammatory disease

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Single blind

Primary purpose

Treatment

Study locations

Center list to be confirmed — check the primary protocol.

Identifiers

NCT: NCT07629037 · REC/RCR & AHS/25/0322

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗