Neuromonitoring in Patients During Aortic Valve Replacement

Brain Injury Clinical Trial

— IMLPBIAVR  

Official title:

The Impact of Intraoperative Microemboli Load on Postoperative Brain Injury in Patients Undergoing Aortic Valve Replacement Preformed With Two Different Surgical Approaches

Clinical Trial Details — Status: Enrolling by invitation

Administrative data

• NCT number: NCT02697786
• Other study ID #: ARRS-RPROJ - J R- 2014- 191
• Status: Enrolling by invitation
• Phase: Phase 3
• First received: January 25, 2016
• Last updated: October 27, 2016
• Start date: January 2016
• Est. completion date: April 2018

Study information

• Verified date: October 2016
• Source: University Medical Centre Ljubljana
• Contact: n/a
• Is FDA regulated: No
• Health authority: Slovenia: Ethics CommitteeSlovenia: Slovenian Research Agency
• Study type: Interventional

Clinical Trial Summary

Postoperative brain damage and neuropsychological disorders have been observed in 30 - 80 % of patients after heart surgery with the use of cardiopulmonary bypass (CPB).They can persist up to a year after cardiac surgery and are associated with increased hospital mortality and prolonged intrahospital stay.

Hypoperfusion,hyperthermia,atrial fibrillation,genetic predisposition and systemic inflammatory response associated with CPB have been identified as pathophysiological mechanisms.However, some authors consider cerebral embolisation to be the prevalent mechanism of intraoperative brain injury after cardiac surgery,as gaseous or solid cerebral emboli can cause ischemia, inflammation and edema,consequently causing cerebral infarctions usually resulting with stroke,coma,encephalopathy, delirium and cognitive decline. Additionally,they may impair cerebrovascular reactivity (CVR).

Aortic valve replacement (AVR) preformed by full sternotomy is the standard approach in the treatment of aortic valve disease. Minimally invasive (MIS) aortic valve replacement has been shown to reduce postoperative mortality, morbidity, and pain while providing faster recovery, a shorter hospital stay, and better cosmetic results. However, due to technically more demanding procedure, MIS may lead to prolonged CPB time and incomplete de-airing of the heart with an increased risk for cerebral gas embolization. Therefore, the choice of MIS might bear an augmented risk for brain injury.

Transcranial Doppler (TCD) enables real time detection of intraoperative emboli in the cerebral arteries seen as microembolic signals (MES), and is an essential neuromonitoring tool. Several studies demonstrated correlation between the number of MES and the occurrence as well as severity of postoperative neurological complications. However, the factors contributing to brain injury have not been elucidated in those studies. The investigators speculate that impairment of CVR is an important mechanism that persists and prolongs the duration of brain injury into postoperative period.

The aim of the study is to compare two surgical approaches used for AVR, with focus on the number of MES and their impact on levels of protein S100B (marker of brain tissue damage),postoperative CVR and cognitive function With the results,the investigators aim to help surgeons in selecting the appropriate technique for AVR in individual participants,as well as to clarify the effect of aortic valve surgery on the brain.

Description:

Patients undergoing for aortic valve replacement will be enrolled in the study after giving the signed informed consent and will be divided in two groups depending on the type of the surgical technique. Either full sternotomy (FS) or minimal invasive sternotomy (MIS) will be performed, both with the use of cardio-pulmonary bypass (CPB).One week before and one week after the surgery patients will undergo mini mental test and measurement of visually evoked cerebral blood flow velocity response (VEFR).Levels of S100B, interleukin (IL) 1, IL 6, IL 8, IL 10 and microparticles will be determined before induction of anesthesia,as well as 6 h, 24 h, 48 h and 7 days after CPB.Each patient will have invasive and non invasive monitoring that will include near infrared spectroscopy (NIRS), bispectral index (BIS) and TCD during surgery.MES will be detected using TCD at the following time-points: beginning of surgery, after sternotomy, during aortic cannulation, during CPB, during de-airing, opening of the clamp on the aorta and after CBP removal before chest closure.All of this data will be documented as well as the demographic characteristics of patients, their preoperative medical status, and intraoperative data (duration of surgery, duration of CPB, hemodynamic parameters, inotropic/vasoactive support,blood and blood components); duration of mechanical ventilation in intensive care unit (ICU), duration of ICU stay, 30-day mortality and morbidity, as well as postoperative complications.

Recruitment information / eligibility

• Status: Enrolling by invitation
• Enrollment: 60
• Est. completion date: April 2018
• Est. primary completion date: December 2017
• Accepts healthy volunteers: No
• Gender: Both
• Age group: 18 Years to 85 Years

Eligibility

Inclusion Criteria:

• Isolated aortic valve stenosis as well as asymptomatic patients with depressed systolic function

• Symptomatic patients with normal or depressed left ventricular function

• Patients with American Society of Anesthesiologist (ASA) physical status classification 2 or 3

Exclusion Criteria:

• History of brain stroke

• EF less than 20%

• History of alcohol abuse

• Epilepsy of history of psychiatric illness and antipsychotic drugs

• Patients with stenosis on carotid arteries

• Patients with preformed surgery or already stented carotid arteries

• Patients with poor or absent acoustic temporal window

• Diagnosed dementia

Study Design

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

Related Conditions & MeSH terms

• Brain Injuries
• Brain Injury

Intervention

Device:
• Transcranial doppler
Prolonged de airing to decrease the number of MES

Locations

Country	Name	City	State
Slovenia	University Clinical center	Ljubljana

Sponsors (2)

Lead Sponsor	Collaborator
Marija Bozhinovska	Slovenian Research Agency

Country where clinical trial is conducted

Slovenia, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Other	Length of ICU stay		Post operative period, an expected average of 2 days	No
Other	Requirement for inotropic and vasoactive therapy		1)After induction of anesthesia, 2)at the end of CPB ,3) postoperative period	No
Other	Duration of mechanical ventilation		postoperative period, an expected average 2 days	No
Other	30 days mortality		30 days	No
Primary	Detection of the intraoperative microembolic signals during minimal invasive sternotomy compared to full sternotomy with TCD during aortic valve surgery		Intraoperative detection:Beginning of surgery, after sternotomy, during aortic cannulation, during CPB, during de-aeration, opening of the clamp on the aorta and after CBP removal before chest closure.	No
Primary	Detection of S100B serum protein, marker of brain tissue damage		Before induction of anesthesia, 6 h , 24 h, 48h and 7 days after CPB	No
Primary	Detection of serum interleukin IL-1, IL-6,IL-8,Il-10 and Microparticles		Before induction of anesthesia, 6 h , 24 h, 48h and 7 days after CPB	No
Secondary	Assessment of cerebrovascular reactivity using visually evoked cerebral blood flow velocity response (VEFR) measurements		7 days before and 7 days after surgery	No
Secondary	Assessment of neurologic and cognitive function in patients undergoing AVR		7 days before and 7 days after surgery	No