Atrial Fibrillation Symptoms and Pain Sensitization

Study Overview
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Brief Summary
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Atrial fibrillation (AF) is the most common sustained arrhythmia and the number of patients with AF is expected to increase substantially in the coming decades. One third of patients with AF report no AF-associated symptoms, but up to one fourth report severe symptoms such as chest pain. It is well recognized, but unclear why patients' experience of AF-related symptoms, including chest pain, varies so much. Patients with chronic pain show a high degree of central sensitization, i.e. facilitated pain responses to repeated painful stimulation and impaired conditioned pain modulation, compared with controls. It is possible that patients with symptomatic AF may have developed pronounced pain sensitization even in the absence of chest pain as a symptom. No previous study has investigated pain sensitization in patients with AF. The primary objective is to assess differences in pain sensitization in patients with symptomatic AF compared with patients with asymptomatic AF. Secondary objectives are to study the association of age, sex, AF duration, comorbidities and health-related quality of life to pain sensitization. A total of 30 patients with permanent AF (15 symptomatic and 15 asymptomatic) will be recruited. Patients will complete an AF-specific symptom score and a generic health-related quality of life questionnaire, and physicians will assess AF-related symptoms. Quantitative sensory testing recordings will be collected by pressure algometry. Assessment of temporal summation of pressure pain and conditioning pain modulation will be used to investigate the involvement of pain sensitization. This preliminary pilot study will be used to estimate sample size for a larger study in which both patients and control subjects will be recruited, to further investigate whether patients with symptomatic AF have increased pain sensitization compared with patients with asymptomatic AF and controls. The studies may have an impact on individualized management of patients with AF in the future.

Official Title
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Pain Sensitization in Patients With Symptomatic Atrial Fibrillation Compared With Asymptomatic Patients

Conditions
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Atrial Fibrillation

Intervention / Treatment
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* Diagnostic Test: Quantitative sensory testing


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Male or female subjects 20 to 75 years old Permanent AF Previously completed AF-6 Written informed consent Exclusion Criteria: Paroxysmal or persistent AF Previous pulmonary vein isolation Psychiatric or cognitive condition Pregnancy Previous/current drug or alcohol abuse Previous neurological or concomitant musculoskeletal condition Continuous analgesic medication

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Health Services Research
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Symptomatic patients<br>Subjects with symptoms of atrial fibrillation i.e. AF-6 sum score 30 points or more. | Diagnostic Test: Quantitative sensory testing<br>* Quantitative sensory testing recordings will be collected by pressure algometry Assessment of temporal summation of pressure pain and conditioning pain modulation will be used to investigate the involvement of pain sensitization.<br>|
| Other: Asymptomatic patients<br>Subjects with no symptoms of atrial fibrillation i.e. AF-6 sum score = 0. | Diagnostic Test: Quantitative sensory testing<br>* Quantitative sensory testing recordings will be collected by pressure algometry Assessment of temporal summation of pressure pain and conditioning pain modulation will be used to investigate the involvement of pain sensitization.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Differences in pain sensitization | A handheld pressure algometer will be used to assess the pressure pain thresholds over the sternum and the tibialis anterior muscle. Low pressure pain thresholds indicate sensitization. A pin prick will be used to induce temporal summation of pressure pain. Ten consecutive stimuli will be applied over the sternum and tibialis anterior muscle and the patient will be asked to rate the pain intensity on the visual analogue scale (minimum 0, maximum 10, higher scores mean worse pain). Temporal summation of pressure pain will be calculated as the difference in the pain intensity between the first and the last stimulation. High temporal summation of pressure pain scores indicate facilitated temporal summation. The conditioning pain modulation index will be assessed as the increase in pain pressure thresholds during cold pressure test. The lower the difference is, the more sensitization. | Day 1 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Correlation of age, sex, AF duration and comorbidities and HRQoL to pain sensitization |  | Day 1 | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Atrial Fibrillation, Symptoms, Quality of Life, Pain, Conditioning pain modulation, Temporal summation