Acute Effect of One Single Bout of High Intensity Exercise on the Tendency for Ventricular Arrhythmia

Study Overview
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Brief Summary
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This study will evaluate the acute effect of one single bout of high intensity exercise on the tendency for ventricular arrhythmia.

Detailed Description
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This study is a substudy of a planned study involving participants with an implantable cardioverter defibrillator (ICD), who will be randomly assigned to either take part in a exercise program for 12 weeks or serve as control and live as usual (Clinical Trials Unique Protocol ID: 2018/1592). In that study all participants will complete an exercise treadmill test to determine maximum oxygen uptake (VO2 peak). In this study we wish to examine the acute effect of one single bout of high intensity exercise (i.e the VO2 peak test) on the tendency for ventricular arrhythmia. The study will evaluate changes in ICD-parameters and the number of premature ventricular contractions the first 24 hours after VO2 peak testing compared to the average number of the 48 hours prior to the test. The study will also examine if the acute effect after VO2 peak testing alters after completing 12 weeks of aerobic interval training or control respectively.

Official Title
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Acute Effect of One Single Bout of High Intensity Exercise. A Substudy of the Study on Physical Activity and Ventricular Arrhythmias

Conditions
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Tachycardia, Ventricular, Defibrillators, Implantable

Intervention / Treatment
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* Behavioral: VO2 peak testing


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with ICD and dilated cardiomyopathy or coronary heart disease as cause for implantation ICD implanted at St Olavs hospital, Trondheim In case of difficulties with patient inclusion for the study, the criteria might be broadened to include patients with idiopathic ventricular arrhythmia as cause for implantation. Exclusion Criteria: inability to accomplish the exercise program due to serious comorbidity or to participate in regular training within the next 3 months due to other reasons signs of severe cardiac ischemia or persistent ventricular tachycardia during individualized treadmill O2 peak test, which after individual assessment is to be found at risk comorbidity where endurance training at more than moderate intensity is discouraged severe cardiac valve disease planned surgery within the next 3 months inability to give informed consent

Ages Eligible for Study
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Minimum Age: 18 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: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: VO2 peak test<br>All participants enrolled in the planned study on physical activity and ventricular arrhythmias and on baseline will complete an exercise treadmill test to determine VO2 peak | Behavioral: VO2 peak testing<br>* Exercise on treadmill starts with  4km/h at 0% inclination before inclination is increased to 4% and speed kept unchanged. Inclination will then be increased with two percent approximately after each minute until exhaustion.<br>* Other names: Cardiopulmonary Exercise Testing (CPET);|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Tendency for ventricular arrhythmia | Measured by changes in the number of premature ventricular contractions the first 24 hours after VO2 peak testing compared to the average number of the 48 hours prior to the test. Registered on a 72 hours Holter monitoring | 24 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in ICD-parameters during a single bout of high intensity exercise (VO2 peak test) | Evaluated by changes in number of inappropriate shocks | 24 hours | 
| Changes in ICD-parameters during a single bout of high intensity exercise (VO2 peak test) | Evaluated by changes in stimulation threshold | 24 hours | 
| Changes in ICD-parameters during a single bout of high intensity exercise (VO2 peak test) | Evaluated by changes in lead impedance | 24 hours | 
| Changes in ICD-parameters during a single bout of high intensity exercise (VO2 peak test) | Evaluated by changes in atrial and ventricular refractory period | 24 hours | 
| Changes in ICD-parameters during a single bout of high intensity exercise (VO2 peak test) | Evaluated by changes in restitution time of the sinus node | 24 hours | 
| Changes in ICD-parameters during a single bout of high intensity exercise (VO2 peak test) | Evaluated by changes in refractory period of the AV-node | 24 hours | 
| Changes in acute effect of one single bout of high intensity exercise on tendency for ventricular arrhythmia after either 3 months of interval exercise or control | Measured by changes in the number of premature ventricular contractions the first 24 hours after VO2 peak testing compared to the average number of the 48 hours prior to the test. Registered on a 72 hours Holter monitoring | Baseline and after 12 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Exercise Training