• Gamboa A, Paranjape SY, Black BK, Arnold AC, Figueroa R, Okamoto LE, Nwazue VC, Diedrich A, Plummer WD, Dupont WD, Robertson D, Raj SR. Inspiratory Resistance Improves Postural Tachycardia: A Randomized Study. Circulation. Arrhythmia and electrophysiology. 2015 Mar 19. PMID: 25792354 [PubMed].

Abstract 

-The objective of this study is to determine the effect of inspiratory resistance through an impedance threshold device (ITD) on orthostatic tolerance in patients with postural tachycardia syndrome (POTS). We hypothesized that the ITD would result in greater negative intrathoracic pressure to enhance cardiac venous return, improve stroke volume, and reduce heart rate in these patients.