Using pulse pressure variation or stroke volume variation to diagnose right ventricular failure?

Abstract

We read with interest two recent studies suggesting that pulse pressure variation (PPV) is not an accurate predictor of fluid responsiveness in subjects with pulmonary hypertension [1,2]. We agree that PPV and stroke volume variation (SVV) may not work in patients with right ventricular (RV) failure. Indeed, when PPV and SVV are related to an inspiratory increase in RV afterload (and not to a decrease in RV preload), they cannot serve as indicators of fluid responsiveness [3]. This is indeed a limitation but can also be seen as useful information for clinicians who do not have an echo probe on the ends of their fingers. PPV and SVV are now available on virtually all bedside and hemodynamic monitors. These parameters have been shown to be very useful for predicting fluid responsiveness in many patients with an arterial line who are mechanically ventilated [3]. When part of goal-directed strategies, these parameters have also been shown able to improve patient outcome [4,5]. As a result, PPV and SVV are now widely used by clinicians in the decision-making process regarding fluid therapy. In this context, the lack of response to a volume load while PPV or SVV is high should be seen as an indicator of RV dysfunction, and should trigger an echocardiographic evaluation to confirm the diagnosis and to understand the underlying mechanisms. In other words, we believe PPV and SVV may actually help clinicians to diagnose quickly and treat properly shock states related to RV failure!