A compare between myocardial topical negative pressure levels of -25 mmHg and -50 mmHg in a porcine model

Abstract

Background: Topical negative pressure (TNP), widely used in wound therapy, is known to stimulate wound edge blood flow, granulation tissue formation, angiogenesis, and revascularization. We have previously shown that application of a TNP of -50 mmHg to the myocardium significantly increases microvascular blood flow in the underlying tissue. We have also shown that a myocardial TNP levels between -75 mmHg and -150 mmHg do not induce microvascular blood flow changes in the underlying myocardium. The present study was designed to elucidate the difference between -25 mmHg and -50 mmHg TNP on microvascular flow in normal and ischemic myocardium.

Novel Strategies in Ischemic Heart Disease

“…Topical negative pressure (TNP) has been used in the treatment of chronic and problematic wounds since the beginning of the 1990´s, and has been shown to increase blood flow and stimulate angiogenesis in the underlying tissue. Because of TNP´s stimulating effect on blood flow and angiogenesis TNP has been tried to be applied directly onto the myocardium, referred to as myocardial topical negative pressure (MTNP) to increase myocardial blood flow and reduce myocardial ischemia, and reduce myocardial infarction (Lindstedt et al 2008a, Lindstedt et al 2007c, Lindstedt et al 2007a, Lindstedt et al 2007b, Lindstedt et al 2008c, Lindstedt et al 2008d).…”

The flaws of laser Doppler in negative‐pressure wound therapy research

“…1 Despite the fact that NPWT increases tissue pressure and that this is incongruous with an increase in perfusion, there remains an overwhelming body of evidence that has shown an immediate increase in perfusion. 2,3,5,[10][11][12][13][14][15][16][17][18][19][20][21][22] This apparent paradox has remained unexplained.…”

“…Almost all of the studies evaluating perfusion changes due to NPWT have made use of laser Doppler. [10][11][12][13][14][15][16][17][18][20][21][22] The laser Doppler measurement of perfusion (perfusion units) is an arbitrary unit that is derived by multiplying the velocity and concentration of red blood cells within a tissue volume (less than 1 mm 3 ). 17,18,23,24 When the light of the laser Doppler encounters a moving red blood cell, it undergoes a wavelength shift explained by the Doppler effect, while the static objects in its path do little to change its wavelength.…”

“…Almost all of the studies evaluating perfusion changes due to NPWT have made use of laser Doppler . The laser Doppler measurement of perfusion (perfusion units) is an arbitrary unit that is derived by multiplying the velocity and concentration of red blood cells within a tissue volume (less than 1 mm 3 ) .…”