Correlation of Pulse Wave Transit Time with Pulmonary Artery Pressure in a Porcine Model of Pulmonary Hypertension

Abstract

For the non-invasive assessment of pulmonary artery pressure (PAP), surrogates like pulse wave transit time (PWTT) have been proposed. The aim of this study was to invasively validate for which kind of PAP (systolic, mean, or diastolic) PWTT is the best surrogate parameter. To assess both PWTT and PAP in six healthy pigs, two pulmonary artery Mikro-Tip™ catheters were inserted into the pulmonary vasculature at a fixed distance: one in the pulmonary artery trunk, and a second one in a distal segment of the pulmonary artery. PAP was raised using the thromboxane A2 analogue U46619 (TXA) and by hypoxic vasoconstriction. There was a negative linear correlation between PWTT and systolic PAP (r = 0.742), mean PAP (r = 0.712) and diastolic PAP (r = 0.609) under TXA. During hypoxic vasoconstriction, the correlation coefficients for systolic, mean, and diastolic PAP were consistently higher than for TXA-induced pulmonary hypertension (r = 0.809, 0.778 and 0.734, respectively). Estimation of sPAP, mPAP, and dPAP using PWTT is feasible, nevertheless slightly better correlation coefficients were detected for sPAP compared to dPAP. In this study we establish the physiological basis for future methods to obtain PAP by non-invasively measured PWTT.

Assessment of long-term sequelae of pulmonary dysfunction associated with COVID-19 using pulmonary pulse transit time

“…investigated the relationship between the pPTT and the estimated pulmonary artery pressure in the porcine model of pulmonary arterial hypertension and found a negative correlation between pPTT and calculated sPAP. [ 21 ] The outcomes of our study were comparable with their reports and demonstrated the strong association between pPTT and impaired pulmonary functions. According to our study, estimated TAPSE, RV FAC, and pPTT measurements were significantly lower among COVID-19 survivors compared to healthy control subjects ( P < 0.05, respectively).…”

Assessment of long-term sequelae of pulmonary dysfunction associated with COVID 19 by using pulmonary pulse transit time

“…According to these studies, this novel index not only identi ed the severity of pulmonary brosis but act as a potential index of pulmonary dysfunction [9]. In another study, Mueller-Graf et al investigated the relationship between the pPTT and the estimated pulmonary artery pressure in the porcine model of pulmonary arterial hypertension and found a negative correlation between pPTT and calculated sPAP [21]. Outcomes of our study were comparable with their reports and demonstrated the strong association between pPTT and impaired pulmonary functions.…”

Pulmonary transit time has close relation with pulmonary pulse wave transit time in normal subjects

“…In general, the peak late systolic (S2), peak diastolic (D) and atrial reversal (A) velocities can be identified from the pulmonary vein spectrum in normal adults. Then, pPTT, defined as the time interval between the R‐wave in the electrocardiogram and the corresponding peak late systolic pulmonary vein flow velocity (R‐PVs2 interval) was measured (Figure 1) (Dogan et al, 2018; Efe et al, 2017; Mueller‐Graf et al, 2021; Wibmer et al, 2015). The pPTT values were measured from three consecutive beats at least and averaged.…”

“…Pulmonary pulse wave transit time (pPTT), defined as the time it takes for the systolic pressure pulse wave to travel from the pulmonary valve to the pulmonary veins, has been recognized as a useful surrogate marker of pulmonary hemodynamic and vascular alterations in pulmonary hypertension (Mueller‐Graf et al, 2021; Prins et al, 2016; Wibmer et al, 2015), pulmonary fibrosis (Wibmer et al, 2015), systemic lupus erythematosus (Efe et al, 2017), systemic sclerosis (Dogan et al, 2018) and other related diseases.…”

“…It is well known that both PTT and pPTT are affected by one or a combination of the following determinants: right ventricular function, pulmonary artery pressure, pulmonary vascular resistance (PVR), and left atrial pressure (Brittain et al, 2015; Colin et al, 2020; Gurbuz et al, 2020; Herold et al, 2016b; de Lepper et al, 2017; Mueller‐Graf et al, 2021; Prins et al, 2016). PTT can only be measured by using contrast agents, no matter which imaging technique is chosen, such as echocardiography, computed tomography and magnetic resonance imaging.…”