Insights into the mechanism of paradoxical low-flow low-pressure-gradient severe aortic stenosis: association with reduced oxygen consumption by the whole body.

This study investigated the relationship between VO2, SVi and AS severity in patients with AS to examine the association between reduced VO2 and PLFLPG AS. In 59 patients (24 men, mean age 78±7 years) with severe AS, SVi, AS severity and type were evaluated by echocardiography, and VO2 was measured by the fraction of O2 in expired gases. The SVi and VO2 were significantly decreased in 20 patients with PLFLPG AS compared to those in 39 patients with non-PLFLPG AS (30±4 vs 41±7 ml/m2 and 2.4±0.5 vs 3.0±0.5 ml/min/kg, p < 0.01, respectively). The SVi to VO2 ratio was not different between the 2 groups (13.1±2.6 vs 13.6±2.1, n.s.). The SVi was independently correlated with VO2 (R=0.74, p<0.01) but not with the aortic valve area index. Categorized PLFLPG AS was also significantly associated with reduced VO2 (p<0.001). PLFLPG AS is associated with reduced VO2 by the whole body, which may offer insights into the mechanism of PLFLPG AS. PMID: 30681367 [PubMed - as supplied by publisher]

https://www.ncbi.nlm.nih.gov/pubmed/30681367?dopt=Abstract

Source: American Journal of Physiology. Heart and Circulatory Physiology - January 25, 2019 Category: Physiology Authors: Onoue T, Iwataki M, Araki M, Itoh H, Isotani A, Umeda H, Fukuda S, Nagata Y, Tsuda Y, Fujino Y, Hanyu M, Ando K, Shirai S, Takeuchi M, Saeki S, Levine R, Otsuji Y Tags: Am J Physiol Heart Circ Physiol Source Type: research