Measuring Absolute Brain Flow and Brain Microcirculation Resistance by Continuous Thermodilution

Official title

Measuring Absolute Brain Flow and Brain Microcirculation Resistance by Continuous Thermodilution: a Pilot Study - RESISTANCE

Overview

Worldwide, cerebrovascular accidents (also known as strokes) are the leading cause of acquired disability, the second-leading cause of dementia (after Alzheimer's disease) and the second-leading cause of death (but the leading cause of death among women). A mechanical thrombectomy (MT) allows the recanalization of the occluded cerebral artery during an acute ischemic stroke, by removing the blood clot with a mechanical device inserted endovascularly under image guidance. MTs are the optimal treatment for a large number of patients presenting an occlusion in an anterior artery (the internal carotid artery and the proximal segment of the middle cerebral artery). Reperfusion is considered satisfactory if the mTICI score at the end of the procedure is of mTICI 2c or mTICI 3. Despite these scores having been obtained by 71% of patients during the randomized trials, showing the superiority of MT over intravenous thrombolysis, only 27% of these patients were free of neurological deficits at 3 months . Therefore, there is a discrepancy between the high rate of macroscopic recanalization and clinical results. One hypothesis to explain this discrepancy is that despite high quality macroscopic recanalization, reperfusion of the cerebral microcirculation remains insufficient: macroscopic recanalization is not equivalent to microscopic reperfusion. This discrepancy also exists in cardiology: despite a high rate of coronary artery recanalization when patients with an ST- segment elevation myocardial infarction are in emergency care, half of these patients later exhibit coronary microvascular dysfunction. The absence of reperfusion is associated with an increased risk of cardiovascular death, recurring myocardial infarctions, cardiogenic shock and heart failure one year after the coronary recanalization for an ST-segment elevation myocardial infarction. It has been shown that continuous intracoronary thermodilution can be used to quantify coronary blood flow and the absolute value of microcirculatory resistance (in Wood units). There are not currently any tools that can quantify cerebral microcirculation immediately after an MT. The aim of this study is to evaluate the feasibility and safety of using a pressure/temperature sensing guidewire to measure cerebral microcirculatory resistance using thermodilution in patients with a score of mTICI 2c or 3 after MT for the management of acute ischemic stroke in the anterior circulation.

Interventions

• Device Measuring Absolute Cerebral Flow and Microvascular Resistance by Thermodilution
  The measurements will be taken as follows: once satisfactory recanalization has been achieved (mTICI 2c or 3), the suction catheter will be placed at the origin of the M1 segment. Through this catheter, the pressure/temperature measurement microguide will be placed at the distal part of M1. The microcatheter will be placed on the microguide, with its tip positioned at the outlet of the aspiration catheter. A pressure sensor will be connected to the aspiration catheter. The microcatheter will be

Primary outcome measures

• The primary objective is to assess the feasibility of measuring cerebral blood flow and cerebral microcirculatory resistance using thermodilution with the rayflow microcatheter and pressurewire guide. [Time frame: Immediately after the measurement of cerebral blood flow and cerebral microcirculatory resistance using thermodilution done with the pressure temperature guidewire]

Secondary outcome measures (4)

• To assess the safety of using thermodilution to measure cerebral blood flow and cerebral microcirculatory resistance [Time frame: Immediately after the measurement of cerebral blood flow and cerebral microcirculatory resistance using thermodilution done with the pressure temperature guidewire]
• To describe the clinical evolution of patients [Time frame: DAY 90]
• Determine the threshold value of the cerebral microcirculation resistance index that allows the definition of an optimal sensitivity/specificity pair for the prognosis of neurological progression (favorable or not). [Time frame: day 90]
• Measure the additional radiation dose received by patient [Time frame: day 1]

Eligibility criteria

Inclusion criteria

• Men or women aged 18 to 80
• Social Security beneficiaries
• Obtained signed consent to participate in the study
• TICI 2c or TICI 3 score after mechanical thrombectomy
• Patients hospitalized for ischemic stroke due to middle cerebral artery thrombosis

Exclusion criteria

• Spasm of an artery without significant stenosis
• Vessel diameter less than 1 mm
• Severe visceral failure
• Local infection
• Minors
• Adults protected by law
• Patients deprived of their liberty
• Subjects who are uncooperative or unable to meet the requirements of the protocol
• Subjects participating in another clinical trial or in a period of exclusion from a previous clinical trial
• Pregnant women

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

N/A

Model

Single group

Masking

Open label

Primary purpose

Device feasibility

Study locations

France · 1 center

• CHU de NICE — Nice

Identifiers

NCT: NCT07566598 · 24-PP-08

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗