The pulmonary artery pulsatility index in patients with severe aortic stenosis undergoing valve replacement

Background and aims: The pulmonary artery pulsatility index (PAPi), that is, the pulmonary artery pulse pressure (PAPP) divided by the mean right atrial pressure (mRAP), is an increasingly used invasive index of right ventricular function. We sought to assess the prognostic impact of the PAPi in unselected patients with aortic stenosis (AS) undergoing aortic valve replacement (AVR). Methods: We studied consecutive patients with severe AS (n = 487, 74 ± 10 years, 58% males) undergoing right heart catheterization prior to AVR with post-AVR follow-up of several years. Results: The mean PAPi was 4.7 ± 3.3, and the mean values in the four PAPi quartiles were 2.1 ± 0.5, 3.2 ± 0.3, 4.5 ± 0.5 and 8.9 ± 4.2. Patients in the lowest PAPi quartile had similar AS severity, symptoms, B-type natriuretic peptide and surgical risk compared with patients in higher quartiles. The lowest PAPi quartile had the lowest PAPP and the highest mRAP and only a slightly reduced stroke volume index (SVI) but the highest pulmonary artery capacitance (PAC). After a median post-AVR follow-up of 45 months mortality did not differ across PAPi quartiles (log rank P = 0.50), which was independent of the AVR mode. However, all contributors of the PAPi equation, that is, higher PAPP, lower PAC (i.e., stroke volume divided by PAPP), lower SVI and higher mRAP were associated with increased mortality. Conclusions: In unselected patients with severe AS, the PAPi did not predict post-AVR mortality. This may be explained by the fact that the low PAPP in those with low PAPi was mainly a reflection of a high PAC rather than a low SVI.