Related Experiment Videos
Spectral analysis of flow velocity in the contralateral artery during coronary angioplasty: a new method for
J J Piek1, J J Koolen, A C Metting van Rijn
1Department of Cardiology, University of Amsterdam, The Netherlands.
Insights
A new method effectively assesses coronary collateral flow and resistance in humans. This technique quantizes the beneficial impact of collateral vessels during acute myocardial infarction, aiding in patient risk stratification.
Area of Science:
- Cardiovascular Medicine
- Interventional Cardiology
- Physiology
Background:
- Coronary collateral vessels are crucial for salvaging myocardium during acute myocardial infarction.
- Quantifying collateral vascular function (flow and resistance) in clinical settings remains challenging.
- Previous studies relied on pathomorphologic and invasive methods, with limited focus on functional assessment.
Purpose of the Study:
- To evaluate a novel method for assessing coronary collateral flow and resistance in conscious individuals.
- To establish a quantitative measure of collateral vascular bed development.
- To correlate collateral vessel function with clinical outcomes during coronary interventions.
Main Methods:
- Utilized angiography and coronary flow velocity measurements (zero-crossing frequency analysis and Fast Fourier Transform spectral analysis) in 38 patients undergoing coronary angioplasty.
- Assessed collateral flow by measuring flow velocity decrease post-balloon deflation.
- Calculated collateral vascular resistance using mean aortic pressure and coronary wedge pressure.
Main Results:
- Fast Fourier Transform spectral analysis detected a significant increase in flow velocity during occlusion in patients with collateral vessels (p < 0.001).
- Collateral vascular resistance was significantly lower in patients with present collateral vessels (p < 0.001).
- Zero-crossing frequency analysis showed lower sensitivity (8%) compared to Fast Fourier Transform (87%) for detecting flow velocity changes.
Conclusions:
- The developed method accurately quantifies coronary collateral flow and resistance.
- Collateral vessels significantly increase flow and reduce resistance during coronary occlusion, mitigating ischemia.
- This technique provides a valuable tool for assessing the functional significance of the collateral vascular bed.
Objectives:
The present study was designed to evaluate a new method for assessing coronary collateral flow and resistance in conscious humans.
Background:
Earlier pathomorphologic and invasive studies have indicated that collateral vessels are important for salvage of myocardium at risk in acute myocardial infarction. Only a few clinical studies have attempted to express the development of the collateral vascular bed in terms of flow or resistance.
Methods:
Angiography and flow velocity measurements of the contralateral coronary artery were performed in 38 patients undergoing coronary angioplasty for one-vessel disease. Coronary flow velocity was assessed by zero-crossing frequency analysis in 37 patients and, additionally, by fast Fourier transform spectral analysis in 23. Collateral flow was determined by the decrease of flow velocity after balloon deflation. Mean aortic pressure and coronary wedge pressure were assessed for calculation of collateral vascular resistance.
Results:
Angiography of the contralateral artery during balloon inflation revealed the presence of collateral vessels in 26 patients (recruitable collateral vessels in 19). Fast Fourier transform spectral analysis demonstrated a significant transient increase of flow velocity during brief coronary occlusion in 15 patients with collateral vessels compared with 8 patients without collateral vessels (4.8 +/- 1.3% vs. 23.4 +/- 17.2%, p < 0.001). A transient increase in flow velocity (> 10%) was less evident by zero-crossing frequency analysis than by fast Fourier transform spectral analysis (sensitivity 8% vs. 87%). The relative resistance of the collateral vascular bed was significantly reduced when collateral vessels were present during coronary occlusion (4.4 +/- 3.8 vs. 16.9 +/- 4.6, p < 0.001). Furthermore, electrocardiographic signs of ischemia were less present in those 15 patients with collateral vessels (p < 0.05).
Conclusions:
The beneficial effect of collateral vessels during brief coronary occlusion is exerted by a significant increase of flow in the contralateral artery in combination with a reduced resistance in the collateral vascular bed. The method presented is capable of expressing the development of the collateral vascular bed in terms of flow and resistance.