Long COVID Symptoms
Conditions
Brief summary
The goal of this clinical trial is to learn whether enhanced external counterpulsation (EECP) therapy can improve cardiopulmonary function and symptoms in adults with long COVID. It will also evaluate the safety and feasibility of two different EECP treatment schedules. The main questions it aims to answer are: * Does EECP therapy improve functional exercise capacity and cardiopulmonary performance in patients with long COVID? * Do different EECP treatment schedules (standard vs. accelerated sessions) lead to different improvements in symptoms, quality of life, and physiological outcomes? * What side effects or medical problems occur during EECP therapy? Researchers will compare two EECP treatment schedules to determine whether a shorter, accelerated program provides similar benefits to the standard schedule. Participants will: * Receive EECP therapy either 1 hour per day (5 days per week for 7 weeks) or 2 hours per day (5 days per week for about 4 weeks), both totaling 35 hours of treatment * Visit the cardiopulmonary rehabilitation clinic regularly for supervised treatment sessions * Complete physical performance tests (such as the Six-Minute Walk Test and cardiopulmonary exercise testing) * Have blood pressure and heart rate measured * Complete questionnaires about symptoms, physical function, sleep quality, and quality of life
Interventions
Participants receive enhanced external counterpulsation (EECP) therapy achieving the same total treatment dose of 35 hours.
Sponsors
National Defense Medical Center, Taiwan
Study design
Allocation
NON_RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Healthy volunteers
No
Inclusion criteria
* Age ≥ 20 years * Eligible for follow-up ≥3 months * A confirmed history of COVID-19 (via PCR or antigen test) * Post-COVID-19 with persistent symptoms ( fatigue, exercise intolerance, dyspnea on exertion, and/or cognitive difficulties) for ≥3 months
Exclusion criteria
* Severe peripheral arterial disease or limb ischemia * Active deep vein thrombosis * Aortic valve regurgitation, * Aortic aneurysm requiring surgical repair * Pregnancy * Other serious cardiovascular conditions contraindicating EECP * Unable to ambulate * Severe neurocognitive impairment precluding consent or cooperation.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Peak oxygen uptake (Peak VO₂) | Baseline and within 1 week after completion of the 35-hour EECP intervention (approximately 4-7 weeks). | Peak oxygen uptake was measured during symptom-limited cardiopulmonary exercise testing (CPET) performed on a cycle ergometer using a ramp protocol (0 W initial workload with increments of 10-15 W per minute). Breath-by-breath gas exchange was continuously recorded using a metabolic cart. Peak VO₂ was defined as the highest 30-second averaged oxygen uptake during the test and expressed in mL·kg-¹·min-¹. Continuous ECG and pulse oximetry monitoring were performed during the test. Exercise was terminated at volitional fatigue or standardized safety criteria. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| The Six-Minute Walk Test (6MWT) | Baseline and again within one week after completing EECP | The Six-Minute Walk Test (6MWT) was used to assess aerobic capacity and endurance. Participants were instructed to walk at their maximal comfortable pace back-and-forth along a 30-meter corridor for 6 minutes, and the total distance walked (in meters) was recorded. One practice trial was done at baseline to familiarize patients, followed by a measured 6MWT at baseline and again within one week after completing EECP. Standard encouragement and stopping criteria were applied. |
| Blood Pressure and Heart Rate | Baseline and weekly, immediately before and after each EECP session, throughout the treatment period. | Resting blood pressure (BP) (systolic and diastolic) and resting heart rate were measured after 5 minutes seated, at baseline and post-intervention. We also tracked any change in these vital signs immediately before and after individual EECP sessions to monitor acute effects. For analysis, we focused on the baseline vs post-intervention resting BP and HR changes. |
| PROMIS Physical Health score | Baseline and within 1 week after completion of the intervention | Physical health status was assessed using the PROMIS Adult Health Profile short form. The Physical Health domain includes items related to fatigue, pain, and physical functioning. Scores were calculated using a summed short-form scale ranging from 4 to 20, with higher scores indicating better physical health. |
| PROMIS Mental Health Score | Baseline and within 1 week after completion of the intervention | Mental health status was assessed using the PROMIS Adult Health Profile short form. The Mental Health domain includes items related to depression, anxiety, and social role functioning. Scores were calculated using a summed short-form scale ranging from 4 to 20, with higher scores indicating better mental health. |
| PROMIS Sleep Disturbance Domain | Baseline and within 1 week after completion of the intervention | Sleep disturbance was evaluated using the PROMIS Sleep Disturbance domain. This measure assesses perceived sleep quality and sleep-related problems, with higher scores indicating greater sleep disturbance. |
| Seattle Angina Questionnaire-7 (SAQ-7) summary score | Baseline and within 1 week after completion of the intervention | Cardiovascular health status was assessed using the Seattle Angina Questionnaire-7 (SAQ-7), a validated instrument evaluating angina frequency, physical limitation, and disease-specific quality of life related to coronary artery disease. Scores range from 0 to 100, with higher scores indicating fewer angina symptoms and better quality of life. |
| COPD Assessment Test (CAT) score | Baseline and within 1 week after completion of the intervention | Respiratory symptom burden was measured using the COPD Assessment Test (CAT), an 8-item questionnaire evaluating symptoms such as cough, dyspnea, chest tightness, and energy level. Total scores range from 0 to 40, with lower scores indicating fewer respiratory symptoms. |
| Rose Dyspnea Scale (RDS) | Baseline and within 1 week after completion of the intervention | Breathlessness severity was evaluated using the Rose Dyspnea Scale (RDS), a 4-item scale assessing dyspnea during physical activities. Scores range from 0 to 4, with higher grades indicating more severe dyspnea. |
| Pittsburgh Sleep Quality Index (PSQI) global score | Baseline and within 1 week after completion of the intervention | Sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI), a validated questionnaire measuring sleep quality and disturbances over the previous month. The instrument includes seven components that generate a global score ranging from 0 to 21. Higher scores indicate worse sleep quality, and a global score greater than 5 indicates poor sleep quality. |
Countries
Taiwan
Outcome results
None listed