Study on Mechanical and Electrical Alternans

Study Overview
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Brief Summary
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The main objective is to investigate mechanical alternans and MTWA in patients with heart failure caused by coronary artery disease to demonstrate a possible correlation between these two phenomena.

Detailed Description
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In patients with severe heart failure and aortic valve disease mechanical alternans or pulsus alternans (a condition in which there is a beat-to-beat oscillation in the strength of cardiac muscle at a constant heart rate) is observed. The mechanisms linking mechanical to electrophysiological dysfunction in heart failure are still under investigation, but impaired calcium cycling is the most striking abnormality of failing myocytes, and is most responsible for contractile dysfunction. Yet it remains unclear how this influences susceptibility to arrhythmias. The MTWA is suggested as a risk marker to identify high risk patients for potential VTEs but the underlying mechanism is not completely understood. The aim of this study is to investigate this in a clinical setting by measuring LV parameters using a PV loop conductance catheter and generate TWA recording simultaneously to demonstrate a possible correlation between these two phenomena in patients with ischemic heart failure and find out if MTWA could turn into a more valuable risk factor. Our hypothesis is that alternating changes in LV filling explains the electrocardiogenesis of TWA by changing the position of the heart relative to the body surface electrodes in an alternating way.

Official Title
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The Connection Between Mechanical Alternans Measured by Pressure-Volume (PV) Loop Catheter in Patients With Ischemic Heart Failure and the Occurrence of Microvolt T Wave Alternans (MTWA)

Conditions
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Heart Failure, Ischemia, Ventricular Arrhythmia

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with heart failure caused by coronary artery disease Indication for left ventricular radiofrequency (LV RF) ablation LVEF ≤ 35% measured by echocardiogram or MRI Exclusion Criteria: hemodynamically instable patients age under 18 and over 85 years, heart failure not caused by coronary artery disease Severe co-morbidity

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 85 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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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Presence or absence of mechanical alternans and MTWA |  | 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Differences in reduced or more preserved LVEF and the occurrence of the two phenomena |  | 1 year | 
| The occurrence of ventricular tachyarrhythmic events. |  | 1 year | 
| Influence of LV compliance on arrhythmogenesis of the infarction border zone. |  | 1 year | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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MTWA, mechanical alternans