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Low frequency mechanical actuation accelerates reperfusion in-vitro.

Marzencki M, Kajbafzadeh B, Khosrow-Khavar F, Tavakolian K, Soleimani-Nouri M, Hamburger J, Kaminska B, Menon C - Biomed Eng Online (2013)

Bottom Line: Alternative or adjunctive emergency therapies that could be initiated by minimally trained personnel in the field are of potential clinical benefit.The experimental results show limited effectiveness of the direct mechanical vibration method and a drastic increase in the patency rate when vessel deformation is induced.For vessel deformation at occlusion site 95% of clots perfused within 11 minutes of application of mechanical stimulus, for vessel deformation 60 centimeters from the occlusion site 95% percent of clots perfused within 16 minutes of stimulus application, while only 2.3% of clots perfused within 20 minutes in the reference system.

View Article: PubMed Central - HTML - PubMed

Affiliation: 1Faculty of Appliced Science, Simon Fraser University, 8888 University Drive, Burnaby, BC, Canada. cmenon@sfu.ca.

ABSTRACT

Background: Rapid restoration of vessel patency after acute myocardial infarction is key to reducing myocardial muscle death and increases survival rates. Standard therapies include thrombolysis and direct PTCA. Alternative or adjunctive emergency therapies that could be initiated by minimally trained personnel in the field are of potential clinical benefit. This paper evaluates a method of accelerating reperfusion through application of low frequency mechanical stimulus to the blood carrying vessels.

Materials and method: We consider a stenosed, heparinized flow system with aortic-like pressure variations subject to direct vessel vibration at the occlusion site or vessel deformation proximal and distal to the occlusion site, versus a reference system lacking any form of mechanical stimulus on the vessels.

Results: The experimental results show limited effectiveness of the direct mechanical vibration method and a drastic increase in the patency rate when vessel deformation is induced. For vessel deformation at occlusion site 95% of clots perfused within 11 minutes of application of mechanical stimulus, for vessel deformation 60 centimeters from the occlusion site 95% percent of clots perfused within 16 minutes of stimulus application, while only 2.3% of clots perfused within 20 minutes in the reference system.

Conclusion: The presented in-vitro results suggest that low frequency mechanical actuation applied during the pre-hospitalization phase in patients with acute myocardial infarction have potential of being a simple and efficient adjunct therapy.

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Related in: MedlinePlus

Pressure and acceleration, setup C. Pressure in the flow system with and without mechanical stimulus and acceleration measured at the actuation site while using setup C.
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Figure 9: Pressure and acceleration, setup C. Pressure in the flow system with and without mechanical stimulus and acceleration measured at the actuation site while using setup C.

Mentions: This work investigates the effect of various types of low frequency mechanical actuation on accelerating vessel reperfusion. In each experiment, one of the three actuation setups described below and depicted in Figures 4, 5 and 6 was used and positioned as depicted in Figure 1. The resulting pressure at the narrowings with no actuation, pressure during actuation and the acceleration at the application site are shown in Figures 7, 8 and 9 for each of the three corresponding setups from Figures 4, 5 and 6. A: The stenosis sites were directly vibrated at 5 g amplitude (2 mm displacement at 24 Hz). The mechanical stimulus was applied at the occlusion site and the lumen of the vessel was not directly deformed. B: Deformation was applied to the occluded vessel 20 mm before each stenosis site. In this case, the vessel was directly deformed and the clot was placed between the narrowing and the application site, but was not directly deformed. The vessel was reaching 80% focal occlusion at the deformation site during actuation. C: Deformation was applied to a vessel with an inside diameter larger than the one of the stenosed vessels, corresponding to the diameter of human aorta in the abdominal region [17]. The actuation site was placed 60 centimeters from the stenosis site. In this case, no mechanical stimuli was applied directly to the narrowings. The amplitude of deformation applied to the large vessel was equal to 3 mm.


Low frequency mechanical actuation accelerates reperfusion in-vitro.

Marzencki M, Kajbafzadeh B, Khosrow-Khavar F, Tavakolian K, Soleimani-Nouri M, Hamburger J, Kaminska B, Menon C - Biomed Eng Online (2013)

Pressure and acceleration, setup C. Pressure in the flow system with and without mechanical stimulus and acceleration measured at the actuation site while using setup C.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4222658&req=5

Figure 9: Pressure and acceleration, setup C. Pressure in the flow system with and without mechanical stimulus and acceleration measured at the actuation site while using setup C.
Mentions: This work investigates the effect of various types of low frequency mechanical actuation on accelerating vessel reperfusion. In each experiment, one of the three actuation setups described below and depicted in Figures 4, 5 and 6 was used and positioned as depicted in Figure 1. The resulting pressure at the narrowings with no actuation, pressure during actuation and the acceleration at the application site are shown in Figures 7, 8 and 9 for each of the three corresponding setups from Figures 4, 5 and 6. A: The stenosis sites were directly vibrated at 5 g amplitude (2 mm displacement at 24 Hz). The mechanical stimulus was applied at the occlusion site and the lumen of the vessel was not directly deformed. B: Deformation was applied to the occluded vessel 20 mm before each stenosis site. In this case, the vessel was directly deformed and the clot was placed between the narrowing and the application site, but was not directly deformed. The vessel was reaching 80% focal occlusion at the deformation site during actuation. C: Deformation was applied to a vessel with an inside diameter larger than the one of the stenosed vessels, corresponding to the diameter of human aorta in the abdominal region [17]. The actuation site was placed 60 centimeters from the stenosis site. In this case, no mechanical stimuli was applied directly to the narrowings. The amplitude of deformation applied to the large vessel was equal to 3 mm.

Bottom Line: Alternative or adjunctive emergency therapies that could be initiated by minimally trained personnel in the field are of potential clinical benefit.The experimental results show limited effectiveness of the direct mechanical vibration method and a drastic increase in the patency rate when vessel deformation is induced.For vessel deformation at occlusion site 95% of clots perfused within 11 minutes of application of mechanical stimulus, for vessel deformation 60 centimeters from the occlusion site 95% percent of clots perfused within 16 minutes of stimulus application, while only 2.3% of clots perfused within 20 minutes in the reference system.

View Article: PubMed Central - HTML - PubMed

Affiliation: 1Faculty of Appliced Science, Simon Fraser University, 8888 University Drive, Burnaby, BC, Canada. cmenon@sfu.ca.

ABSTRACT

Background: Rapid restoration of vessel patency after acute myocardial infarction is key to reducing myocardial muscle death and increases survival rates. Standard therapies include thrombolysis and direct PTCA. Alternative or adjunctive emergency therapies that could be initiated by minimally trained personnel in the field are of potential clinical benefit. This paper evaluates a method of accelerating reperfusion through application of low frequency mechanical stimulus to the blood carrying vessels.

Materials and method: We consider a stenosed, heparinized flow system with aortic-like pressure variations subject to direct vessel vibration at the occlusion site or vessel deformation proximal and distal to the occlusion site, versus a reference system lacking any form of mechanical stimulus on the vessels.

Results: The experimental results show limited effectiveness of the direct mechanical vibration method and a drastic increase in the patency rate when vessel deformation is induced. For vessel deformation at occlusion site 95% of clots perfused within 11 minutes of application of mechanical stimulus, for vessel deformation 60 centimeters from the occlusion site 95% percent of clots perfused within 16 minutes of stimulus application, while only 2.3% of clots perfused within 20 minutes in the reference system.

Conclusion: The presented in-vitro results suggest that low frequency mechanical actuation applied during the pre-hospitalization phase in patients with acute myocardial infarction have potential of being a simple and efficient adjunct therapy.

Show MeSH
Related in: MedlinePlus