Related Experiment Video
Updated: Jun 4, 2025
Interventional Diagnostic Procedure: A Practical Guide for the Assessment of Coronary Vascular Function
Published on: March 15, 2022
Effect of Guiding Catheter Extubation During Physiological Assesment of Stenosis
Salma Raghad Karim1, Jelmer Sybren Westra1, Laust Dupont Rasmussen2,3
1Department of Cardiology, Aarhus University Hospital, Aarhus, Denmark.
Insights
Extubation of the coronary guiding catheter significantly decreases fractional flow reserve (FFR) and increases the index of microcirculatory resistance (IMR), impacting diagnostic accuracy in invasive coronary angiography.
Area of Science:
- Cardiovascular Medicine
- Interventional Cardiology
- Diagnostic Imaging
Background:
- Guiding catheter removal during invasive coronary angiography (ICA) can alter coronary flow and pressure measurements.
- Accurate physiological assessment is crucial for diagnosing coronary artery disease.
Purpose of the Study:
- To evaluate the impact of guiding catheter extubation on fractional flow reserve (FFR), coronary flow reserve (CFR), and index of microcirculatory resistance (IMR).
- To determine if proximal flow area correlates with changes in FFR, CFR, and IMR post-extubation.
Main Methods:
- A subgroup analysis of the Dan-NICAD 2 study included 84 patients with chronic coronary syndrome.
- Physiological measurements (FFR, CFR, IMR) were performed with the guiding catheter intubated and extubated.
- Three-dimensional quantitative coronary angiography assessed proximal flow area.
Main Results:
- FFR decreased significantly (0.82 to 0.80, p<0.001), with 8.7% of patients showing a shift to ≤0.80.
- IMR increased significantly (16.8 to 21.4, p=0.002).
- CFR showed no significant change (3.09 vs. 2.84, p=0.12).
Conclusions:
- Guiding catheter extubation leads to a decrease in FFR and an increase in IMR.
- These changes can potentially alter the interpretation of coronary physiology.
- No correlation was found between proximal flow area and the observed changes in FFR or IMR.
Background:
Extubation of the coronary guiding catheter may affect flow and pressure measurements in the coronary vessel during invasive coronary angiography (ICA).
Aim:
This study aims to investigate the impact of guiding catheter extubation on fractional flow reserve (FFR), coronary flow reserve (CFR), and the index of microcirculatory resistance (IMR).
Methods:
This predefined subgroup analysis of the Dan-NICAD 2 study included patients with chronic coronary syndrome referred to ICA based on a coronary computed tomography angiography. Thermodilution was performed in all vessels evaluated with 30%-90% diameter stenosis on a visual estimate. The primary endpoints were FFR, CFR, and IMR changes when the guiding catheter was extubated from the coronary ostium. Three-dimensional quantitative coronary angiography analysis was conducted to evaluate whether the proximal flow area, defined as the area of the guiding catheter subtracted from the area of the vessel ostium, correlated with the changes in FFR, CFR, and IMR.
Results:
In 84 patients, coronary physiological measurements were performed twice: once with the guiding catheter intubated and once extubated. FFR decreased during guiding catheter extubation (0.82 ± 0.09 vs. 0.80 ± 0.10) with a mean difference of 0.02, 95% CI [0.01-0.03], p < 0.001. Following extubation, eight patients (8.7%) showed FFR values shifting from > 0.80 to ≤ 0.80. IMR increased during guiding catheter extubation (16.8 ± 8.50 vs. 21.4 ± 16.1) with mean difference of 4.67 [95% CI 1.74-7.60], p = 0.002. No significant changes in CFR were observed; intubated 3.09 ± 1.31 vs 2.84 ± 1.30; difference mean 0.25, [95% CI -0.07 to 0.56], p = 0.12. No significant correlations were found between the proximal flow area and the difference in FFR, CFR, and IMR from intubated to extubated: (r -0.14, p = 0.23), (r -0.11, p = 0.34), and (r -0.16, p = 0.17), respectively.
Conclusion:
Extubating the guiding catheter decreased FFR and increased IMR. This resulted in an FFR decrease from > 0.80 to ≤ 0.80 in 8.7% of patients. CFR remained unchanged. No significant correlation was found between FFR/IMR changes and proximal flow area.
More Related Videos
06:51Author Spotlight: Development of a Minimally Invasive Large-Animal Model for Reliable and Reproducible Cardiovascular Research
Published on: October 20, 2023
04:30Endotracheal Intubation Using a Flexible Intubation Endoscope as a Standardized Model for Safe Airway Management in Swine
Published on: August 25, 2022
Related Concept Videos
01:24Endotracheal Tube Extubation
Procedure
Extubation removes the endotracheal tube (ETT) from the patient on mechanical ventilation. It requires a well-coordinated, multidisciplinary approach involving physicians, nurses, respiratory therapists, and other healthcare professionals....
01:29Suctioning the Nasopharyngeal Airway
Equipment Required
01:23Tracheostomy Suctioning II: Procedure
01:17Endotracheal Intubation II: Nursing Management
1. Nursing Care of Patients Before Intubation
Before the endotracheal intubation procedure, nurses play an essential role in ensuring the process goes smoothly. The nurses must be familiar with intubation...
01:26Endoscopic Studies II: Thoracocentesis
Description
Excess pleural fluid or air may accumulate in some respiratory disorders in the thoracic cavity. To treat pleural effusion, a physician conducts thoracentesis by carefully piercing the chest wall and entering...
01:15Endotracheal Intubation I: Procedure
The ET tube comprises various components, including a standard adaptor to attach a bag-valve-mask (BVM) or ventilator, a cuff, a pilot balloon, and radiopaque markings along its length to measure the insertion distance. The tube sizes...