TCD Detection of Gas and Solid Micro-Emboli in Patients Undergoing Coronary Artery Bypass Grafting (CABG): The Influence of Proximal Anastomosis Technique

Postoperative Complications Clinical Trial

Official title:

Gas and Solid Brain Microembolization Detected by the EmbodopR TCD System During Proximal Coronary Graft Anastomosis Done With Aortic Cross Clamping, Partial Occlusion or the HeartstringR Device and Their Effect on Neurocognitive Performance After Coronary Bypass Operation

Clinical Trial Details — Status: Recruiting

Administrative data

• NCT number: NCT00294814
• Other study ID #: EMBO_CTIL
• Status: Recruiting
• Phase: N/A
• First received: February 20, 2006
• Last updated: March 19, 2007

Study information

• Verified date: May 2006
• Source: Rambam Health Care Campus
• Contact: Adler Zvi, MD
• Phone: 972-50-2061069
• Email: z_adler[@]rambam.health.gov.il
• Is FDA regulated: No
• Health authority: Israel: Israeli Health Ministry Pharmaceutical Administration
• Study type: Interventional

Clinical Trial Summary

The purpose of this study is to test the hypothesis that using three different techniques to anastomose coronary grafts to the aorta: partial occlusion, single cross clamp, or using the Heartstring anastomotic device, will change the amount of gas and solid microemboli as detected by the EmbodopR transcranial Doppler (TCD) system and consequently the neurocognitive performance of patients after coronary bypass operation.

Description:

It is not uncommon for a cardiac surgical patient to have his heart fixed but his brain damaged. Sometimes the damage is overt and manifests itself as a major neurological deficiency. The frequency of stroke, the so called type 1 damage, is reported to be between 1 and 4 percent. This may increase mortality from 1.4% to 22% and hospitalization from 6.6 days to 17.5 days. Diffuse encephalopathy, presenting as delirium, confusion, coma and seizures, so called type 2 damage, is reported to appear in a much higher frequency of 3% to 7%, depending on timing and methods of evaluation. This type of damage will increase mortality from 1.4% to 7.5% and hospitalization from 6.6% to 15.2%. Sometimes it is more subtle and appears as neurocognitive decline. This type of damage may be found in 53% of the patients at discharge, in 24% after six months and the frequency rises again to 42% at five years. The impact on the patient and his family might be devastating and the burden on the medical system and society enormous. Long term, moderate to severe disability may affect 69% of the stroke patients and survival may decline to 67% after one year.

After years of research efforts it became evident that inadequate global blood flow to the brain is relatively uncommon and cerebral hemorrhage is a rare cause of brain damage during cardiac operations. It also became evident that one of the most important damage mechanisms is embolization to the brain and the inflammatory response which amplifies the ischemic embolic damage. Looking for possible embolic sources by monitoring embolic signals (HITS) on the transcranial doppler (TCD) tracings, researchers found that manipulation of the aorta during cardiac surgery, like cannulation and especially clamping is a major source of emboli. Using the side biting clamp while performing proximal anastomosis has the potential to crush the aortic wall and release macro and micro emboli especially when the aorta is atherosclerotic. Using a single cross clamp technique might eliminate the aortic wall solid debris but introduce air emboli instead.

Dealing with the same problem, a few proximal anastomotic devices have been introduced and most of them withdrawn from the market because of inferior patency rate. The Heartstring proximal anastomotic device is one of the recently introduced devices for which early good patency rate has been demonstrated. The advantages, in terms of less brain embolization or improved neurologic outcome, have never been demonstrated for the Heartstring or any other anastomotic device.

A recent potential breakthrough in this field of emboli research and prevention in order to improve neurologic outcome after cardiac surgery is the introduction of the EmbodopR system by DWL. This is a high quality TCD system which has been further developed to monitor cerebral emboli. It contains a module which automatically screens every event suspected as embolic, eliminates those recognized as artifacts according to four different criteria and records only real embolic events. Another module can differentiate every event as gas or solid emboli by simultaneously insonating the middle cerebral artery blood with tow ultrasound beams, each of different frequency. The result is a new ability for real time monitoring and characterization of embolic events during cardiac operations.

Recruitment information / eligibility

• Status: Recruiting
• Enrollment: 100
• Accepts healthy volunteers: No
• Gender: Both
• Age group: N/A and older

Eligibility

Inclusion Criteria:

• Patients hospitalized for surgical coronary revascularization at the Department of Cardiac Surgery of Rambam Medical Center, Haifa, Israel.

• Patients should be conscious and cooperative to perform neurocognitive evaluation.

Exclusion Criteria:

• Patients that lack "temporal window" for TCD monitoring will be excluded.

Study Design

Allocation: Randomized, Endpoint Classification: Safety/Efficacy Study, Intervention Model: Parallel Assignment, Masking: Open Label, Primary Purpose: Prevention

Related Conditions & MeSH terms

• Embolism and Thrombosis
• Intracranial Embolism
• Intracranial Embolism and Thrombosis
• Postoperative Complications

Intervention

Device:
• Proximal anastomosis using Heartstring anastomotic device

Locations

Country	Name	City	State
Israel	Dr Zvi Adler	Haifa.

Sponsors (1)

Lead Sponsor	Collaborator
Rambam Health Care Campus

Country where clinical trial is conducted

Israel, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Number of gas\solid microemboli detected by TCD
Primary	Neurocognitive performance
Secondary	Mortality
Secondary	Organ failure (including brain damage)
Secondary	Intensive care unit (ICU) length of stay\hospitalization