Enhancement of Contrast Opacification for Echocardiographic Imaging of the Right Heart and Shunts

Not Applicable

Completed

• Conditions: Bidirectional Cardiovascular Shunt
• Interventions: Procedure: Transthoracic Echocardiogram (TTE); Procedure: Transesophageal Echocardiogram (TEE); Other: Saline/Air Mixture; Other: Saline/Blood Mixture

• Registration Number: NCT02661529
• Lead Sponsor: Mayo Clinic

Brief Summary

The study aims to answer whether the use of a mixture of blood and saline alone (limited air) provides the same degree of right-heart contrast enhancement as compared to the standard agitated saline (with air), during two types of echocardiograms.

Detailed Description

A cardiovascular shunt is an abnormality of the blood flow between the sides of the heart or between the systemic and pulmonary circulation. A right-to-left shunt diverts blood from the right side of the heart to the left side or from the pulmonary to the systemic circulation through an anomalous opening such as septal defect or patent ductus arteriosus. To visualize the shunt during an echocardiogram, agitated saline solution is injected intravenously to provide air microbubble contrast which opacifies (makes visible) the right heart chambers and is the standard used for the non-invasive detection of right to left intracardiac or intrapulmonary shunts. However, agitated saline has the potential risk of air microembolism. Although this type of adverse event is uncommon (\<1% of strokes are related to air embolism), there have been reports in the literature of a number of small strokes/transient ischemic attacks following agitated saline injections at the time of echocardiographic studies. Mixing blood with saline substantially reduces the amount of air introduced, and this study will attempt to quantify the differences in the degree of contrast enhancement.

100 patients scheduled for either Transesophageal Echocardiogram (TEE) or Transthoracic Echocardiogram (TTE) will be studied to determine the degree of contrast enhancement, when using a Saline/Air mixture versus a Saline/Blood mixture. Fifty participants of each type of echocardiography will be studied. The standard agitated saline mixture consists of 10 milliliters of sterile saline and 0.5 milliliters of air agitated together in a syringe prior to injection. The agitated Saline/Blood mixture consists of 9 milliliters of sterile saline and 0.5 - 1 milliliter of blood and agitated together in a syringe prior to injection.

All study participants will complete the routine clinical echocardiography (either a TEE or a TTE) with peripheral injection of agitated Saline/Air mixture, via an intravenous (IV) cannula attached to a three way stop cock. Blood removed from the patient will be withdrawn through the IV into a syringe and agitated with saline and then re-injected into the patient through the same tubing. After completion of the standard clinical imaging for shunt, the Saline/Blood mixture will be infused and an image obtained for comparison.

For each study, digital images will be stored and an Investigator who does not know which treatment arm/mixture was used for a given image, will subsequently rate image quality and assign an image score using a semi-quantitative scale: 0 = poor/no right atrial opacification, 1 = average right atrial opacification, 2 = good right atrial opacification. After all images are analyzed, the scores will be compared for both TEE and TTE studies.

Study Timeline

• Study First Submitted: 2015-09-29
• Study Start: 2016-01
• Study First Submitted QC: 2016-01-21
• Study First Posted: 2016-01-22
• Primary Completion: 2016-07
• Study Completion: 2016-07
• Status Verified: 2017-10
• Last Update Submitted: 2017-10-25
• Last Update Posted: 2017-10-26

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 100

Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Transesophageal Echocardiogram	Saline/Blood Mixture	Patients undergoing an Transesophageal Echocardiogram (TEE) for diagnostic purposes to detect a cardiac shunt abnormality, using Saline/Air Mixture and Saline/Blood Mixture for vessel contrast
Transthoracic Echocardiogram	Saline/Blood Mixture	Patients undergoing an Transthoracic Echocardiogram (TTE) for diagnostic purposes to detect a cardiac shunt abnormality, using Saline/Air Mixture and Saline/Blood Mixture for vessel contrast
Transesophageal Echocardiogram	Saline/Air Mixture	Patients undergoing an Transesophageal Echocardiogram (TEE) for diagnostic purposes to detect a cardiac shunt abnormality, using Saline/Air Mixture and Saline/Blood Mixture for vessel contrast
Transthoracic Echocardiogram	Saline/Air Mixture	Patients undergoing an Transthoracic Echocardiogram (TTE) for diagnostic purposes to detect a cardiac shunt abnormality, using Saline/Air Mixture and Saline/Blood Mixture for vessel contrast
Transthoracic Echocardiogram	Transthoracic Echocardiogram (TTE)	Patients undergoing an Transthoracic Echocardiogram (TTE) for diagnostic purposes to detect a cardiac shunt abnormality, using Saline/Air Mixture and Saline/Blood Mixture for vessel contrast
Transesophageal Echocardiogram	Transesophageal Echocardiogram (TEE)	Patients undergoing an Transesophageal Echocardiogram (TEE) for diagnostic purposes to detect a cardiac shunt abnormality, using Saline/Air Mixture and Saline/Blood Mixture for vessel contrast

Primary Outcome Measures

Name	Time	Method
Degree of right atrial opacification on echocardiogram image	Day 1	The degree of right atrial opacification during echocardiogram will be rated with an image score; 0: poor/no opacification, 1: average opacification, 2: good opacification

Trial Locations

Locations (1)

Mayo Clinic in Rochester; 🇺🇸 Rochester, Minnesota, United States