Are Peripheral Arterial Dysfunction and Stiffness Associated With PAH?

Pulmonary arterial dysfunction and stiffness are associated with pulmonary arterial  hypertension (PAH) and its severity, according to a cross-sectional study of PAH conducted in Barcelona, Spain. Study researchers also found heightened arterial stiffness in patients with systemic sclerosis (SSc) and that patients with HIV most likely experience peripheral endothelial dysfunction (PED) prior to pulmonary hypertension (PH). These results were presented at the American Thoracic Society (ATS) 2022 Annual Meeting, held in San Francisco, CA, May 13 to 18.

Because peripheral endothelial dysfunction is an indicator of heart disease and may be involved in PAH, authors of the current study sought to establish an association between PAH severity and peripheral endothelial dysfunction/arterial stiffness; they also examined the effect of PAH treatment on PED and PAS.

The researchers selected 95 patients whose PAH was categorized as idiopathic (IPAH, n=39), systemic sclerosis-related (SSc-PAH, n=40), or HIV-related (HIV-PAH, n=16). The PAH patients were compared with 41 healthy individuals as well as patients with SSc (n=16) and HIV infection (n=12) who did not have (PH).

The analysis showed that every PAH group had lower flow-mediated dilatation on the brachial artery as well as greater pulse wave velocity (PWV) and a higher augmentation index normalized at a heart rate of 75 beats per minute (AI75) than the healthy participants. These results indicated PED and increased arterial stiffness.

The results also showed that HIV-positive patients had PED whether or not they had PH. Arterial stiffness was found to be linked with baseline SSc. Arterial stiffness was observed to be normal in the HIV-positive patients, but went up in the IPAH patients who were treatment naive (9.97 ± 3.38 m/s; P =.009).

Further results indicated that greater arterial stiffness was associated with more limited exercise capability and more severe PH. PWV was linked with meanpulmonary arterial pressure (bivariable coefficient of determination [r] -0.3; P =.012) and brain natriuretic peptide level (r +0.4, P =.03)PWV and AI75 also were associated with the World Health Organization functional class [WHO FC] for pulmonary hypertension, partial pressure of oxygen, and the 6-minute walking test (6MWT).

The researchers also found that long-term treatment for PAH improved peripheral vascular disease. “Although we did not find significant improvement in peripheral performance after 3 months of treatment, those patients under long-term treatment showed significant changes in all FMD, PWV and AI75,” the authors reported. “Patients that improved stiffness after treatment also covered longer distance in the 6MWT (+72 vs +24 m), had greater decrease in BNP (-160 vs -110 pg/mL) and [were included in the] higher proportion of patients in WHO-FC I-II (63% vs 50%),” they added.

Reference

Garcia AR, Blanco I, Torralba-Garcia Y, et al. Peripheral endothelial dysfunction and arterial stiffness in pulmonary arterial hypertension: association with severity and changes after treatment. Presented at: the American Thoracic Society (ATS) 2022 Annual Meeting; May 13-18, 2022; San Francisco, CA. Abstract 619.