Characterization of Ischemia Related Changes in Esophageal Electrocardiography

This study has been completed.
Sponsor:
Information provided by:
University Hospital Inselspital, Berne
ClinicalTrials.gov Identifier:
NCT01390155
First received: July 1, 2011
Last updated: May 23, 2013
Last verified: May 2013
  Purpose

Esophageal electrocardiography (eECG) has important advantages compared to standard ECG recordings.

Coronary artery disease leading to myocardial ischemia is very common and has potentially severe consequences for patients. To date, the investigators don't know the influence of ischemia on the eECG. The goal of the present study is to assess ischemic changes of the eECG induced by balloon occlusion of coronary arteries in patients undergoing coronary angiography.


Condition Intervention
Coronary Artery Disease
Procedure: Measurement of coronary collateral flow index

Study Type: Observational
Study Design: Time Perspective: Prospective
Official Title: Characterization of Ischemia Related Changes in Esophageal Electrocardiography

Resource links provided by NLM:


Further study details as provided by University Hospital Inselspital, Berne:

Primary Outcome Measures:
  • ST-segment-elevation/depression in the ECG at J-point and 80ms later [ Time Frame: 0, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110 and 120 seconds after start of vessel occlusion ] [ Designated as safety issue: No ]

Secondary Outcome Measures:
  • Increase/decrease of T-wave amplitude [ Time Frame: 0, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110 and 120 seconds after start of vessel occlusion ] [ Designated as safety issue: No ]
  • Relative ST-segment-elevation/depression [ Time Frame: 0, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110 and 120 seconds after start of vessel occlusion ] [ Designated as safety issue: No ]
  • Sensitivity and specificity of the esophageal electrocardiogram detecting ischemic conditions (using the intracoronary ecg as gold standard) [ Time Frame: at the end of occlusion, expected on average to be 60 seconds ] [ Designated as safety issue: No ]
  • New U-wave [ Time Frame: during the whole occlusion time, expected on average to be 60 seconds ] [ Designated as safety issue: No ]
  • beat-to-beat alternans of the ST-segment [ Time Frame: during the whole occlusion time, expected on average to be 60 seconds ] [ Designated as safety issue: No ]

Enrollment: 45
Study Start Date: July 2011
Study Completion Date: May 2013
Primary Completion Date: May 2013 (Final data collection date for primary outcome measure)
Groups/Cohorts Assigned Interventions
1
Patients undergoing temporary myocardial ischemia produced by a one-minute balloon occlusion of the proximal left anterior descending coronary artery.
Procedure: Measurement of coronary collateral flow index
One-minute balloon occlusion of the proximal left anterior descending coronary artery inducing a controlled short-time ischemic condition of a part of the myocardium and simultaneous evaluation of collateral flow.
2
Patients undergoing temporary myocardial ischemia produced by a one-minute balloon occlusion of the proximal left circumflex artery.
Procedure: Measurement of coronary collateral flow index
One-minute balloon occlusion of the proximal left circumflex artery inducing a controlled short-time ischemic condition of a part of the myocardium and simultaneous evaluation of collateral flow.
3
Patients undergoing temporary myocardial ischemia produced by a one-minute occlusion of the proximal right coronary artery.
Procedure: Measurement of coronary collateral flow index
One-minute balloon occlusion of the proximal right coronary artery inducing a controlled short-time ischemic condition of a part of the myocardium and simultaneous evaluation of collateral flow.
4
Patients undergoing temporary myocardial ischemia produced by a one-minute occlusion of the target vessel.
Procedure: Measurement of coronary collateral flow index
One-minute balloon occlusion of the target vessel (the vessel which shows a significant stenosis and accordingly requires a therapeutical intervention by balloon angioplasty and stenting) inducing a controlled short-time ischemic condition of a part of the myocardium and simultaneous evaluation of collateral flow.

Detailed Description:

Background

Heart rhythm disorders frequently occur in the general population and potentially have serious consequences. Atrial fibrillation, the most common atrial arrhythmia, can lead to intracardiac blood clot formation an subsequent embolisation. Esophageal electrocardiography (eECG) provides detailed information about the electrical activity of the atria. Due to the good signal quality, eECG is a promising technique for rhythm monitoring.

Patients undergoing rhythm monitoring may also show signs of other cardiac diseases, particularly coronary artery disease (CAD) due to its high prevalence. It is therefore mandatory to define the ischemic changes in the esophageal ECG.

In CAD atherosclerotic processes narrow the lumen of coronary arteries and may cause exercise-induced ischemia (stable CAD). More importantly, there is also the risk of plaque rupture and subsequent blood clot formation. This cascade can lead to total occlusion of the coronary vessel and myocardial infarction.

Coronary angiography is used to determine the severity of coronary artery stenosis. This simple approach turned out to be useful in clinical routine. However, presence or absence of coronary collaterals is one of the reasons why coronary angiography alone may fail to define the clinical relevance of CAD. Collateral vessels as natural bypasses can grow and act as "backup" blood supply of the myocardial area at risk and can therefore reduce infarct size. The coronary wedge-pressure method is recognized as the scientific and clinical gold standard. Collateralization is an important confounder which also can "mask" ischemic changes on the ECG.

The surface ECG of an important portion of patients undergoing arrhythmia screening also shows signs of myocardial ischemia due to CAD or left ventricular hypertrophy. As with the surface ECG, it is conceivable that ischemic changes occur in the eECG. The characterization of ischemia related changes in eECG is crucial in order to guarantee the proper classification of eECG events. To date, the characterization of such changes is not adequate in order to allow the reliable clinical interpretation of eECG changes.

Objective

  • To characterize changes in the esophageal ECG induced by myocardial ischemia due to short-time coronary occlusion.
  • To determine the influence of coronary collateral vessels on these changes.

Methods

Patients referred for elective coronary angiography will be randomized to four groups:

  1. Patients undergoing temporary myocardial ischemia produced by a one-minute balloon occlusion of the proximal left anterior descending (LAD) coronary artery.
  2. Patients undergoing temporary myocardial ischemia produced by a one-minute balloon occlusion of the proximal left circumflex artery.
  3. Patients undergoing temporary myocardial ischemia produced by a one-minute balloon occlusion of the proximal right coronary artery.
  4. Patients undergoing temporary ischemia produced by a one-minute occlusion of the target vessel (the vessel which shows a significant stenosis and accordingly requires a therapeutical intervention).

During the occlusion, collateral flow indexes will be calculated. Simultaneously, surface ECG, esophageal ECG and intracoronary ECG will be registered.

  Eligibility

Ages Eligible for Study:   18 Years and older
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Sampling Method:   Probability Sample
Study Population

Patients referred for elective coronary angiography due to suspected or known coronary artery disease.

Criteria

Inclusion Criteria:

  • Patients referred for elective coronary angiography
  • Age >/= 18 years
  • Written informed consent to participate to this study

Exclusion Criteria

  • Seve mitral- or aortic valve disease
  • Acute coronary infarction
  • Known bleeding diathesis
  • Systolic blood pressure >200mmHg
  • History of operations of the esophagus
  • Active disease of the upper respiratory and gastroesophageal tract
  • Radiofrequency ablation of atrial fibrillation, less than six weeks ago
  • Right and left bundle branch block
  • Significant Q-waves in the surface leads as indicators for prior myocardial infarction
  • Pregnancy
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT01390155

Locations
Switzerland
Dep. of Cardiology, Bern University Hospital
Bern, Switzerland, 3010 Bern
Sponsors and Collaborators
University Hospital Inselspital, Berne
Investigators
Study Director: Rolf Vogel, MD, MD-PhD
  More Information

No publications provided

Responsible Party: Vogel Rolf, Prof. Dr. med., University Hospital Bern
ClinicalTrials.gov Identifier: NCT01390155     History of Changes
Other Study ID Numbers: 058/11
Study First Received: July 1, 2011
Last Updated: May 23, 2013
Health Authority: Switzerland: Independent Local Research Ethic Commission (Ethikkommission)

Keywords provided by University Hospital Inselspital, Berne:
Electrocardiography
Coronary Artery Disease
Atrial Fibrillation
Heart Atria
Coronary Circulation
Ischemia

Additional relevant MeSH terms:
Coronary Artery Disease
Myocardial Ischemia
Coronary Disease
Ischemia
Heart Diseases
Cardiovascular Diseases
Arteriosclerosis
Arterial Occlusive Diseases
Vascular Diseases
Pathologic Processes

ClinicalTrials.gov processed this record on August 28, 2014