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Blood flow changes in normal and ischemic myocardium during topically applied negative pressure
Sandra Lindstedt1, Malin Malmsjö, Richard Ingemansson
1Department of Cardiothoracic Surgery, Lund University Hospital, Lund, Sweden. sandra.lindstedt@skane.se
The Annals of Thoracic Surgery
|July 24, 2007
Summary
Topical negative pressure (TNP) therapy significantly boosts microvascular blood flow in normal, ischemic, and reperfused heart muscle. This finding suggests TNP could be a new treatment for conditions involving reduced blood flow to the heart.
Area of Science:
- Cardiovascular Research
- Medical Technology
- Wound Healing Research
Background:
- Topical negative pressure (TNP) therapy is a recognized treatment for wound healing, known to enhance blood flow.
- Improving microvascular blood flow in the myocardium is critical for patients with ischemic heart disease to prevent infarction.
- The study investigates the impact of TNP on myocardial microvascular blood flow.
Purpose of the Study:
- To determine the effect of TNP on microvascular blood flow in the myocardium.
- To assess TNP's efficacy in normal, ischemic, and reperfused myocardial tissue.
Main Methods:
- The study involved six pigs undergoing median sternotomy.
- Laser Doppler velocimetry was used to measure myocardial microvascular blood flow.
- Measurements were taken before and after TNP application in normal, ischemic (20 min LAD occlusion), and reperfused states.
Main Results:
- TNP application significantly increased microvascular blood flow in all tested conditions (normal, ischemic, reperfused myocardium).
- In normal myocardium, flow increased from 14.7 to 25.8 PU (p < 0.05).
- In ischemic myocardium, flow increased from 7.2 to 13.8 PU (p < 0.05), and in reperfused myocardium, from 10.8 to 19.3 PU (p < 0.05).
Conclusions:
- TNP therapy demonstrably enhances microvascular blood flow in the myocardium across normal, ischemic, and reperfused states.
- These findings indicate that TNP may represent a novel therapeutic strategy for managing ischemic myocardial conditions.
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