Squatting: the hemodynamic change is induced by enhanced aortic wave reflection

Murakami1 has shown convincingly that wave reflection is increased by squatting, and is responsible for increase in aortic systolic pressure. The author argues persuasively that this mechanism in patients with tetralogy of Fallot could explain reduced right-to-left shunting and relief from cyanotic episodes. It is surprising that this mechanism has not been suggested in the past, but investigators could have been misled by amplification of the pressure waveform, which, with squatting, could have caused a lesser increase in brachial than in aortic systolic pressure. The authors measured both brachial and aortic systolic pressure before and after squatting, but only reported changes in aortic systolic pressure. What was the change in brachial systolic pressure with squatting? I expect that such change was considerably less than the change in aortic systolic pressure.