Arterial structure and function in patients with hemoblastoses before and after high-dose chemotherapy and autologous hematopoietic stem cell transplantation

Background: High dose chemotherapy (HDCT) preceding autologous hematopoietic stem cell transplantation (autoSCT) can be toxic for cardiovascular system, which can be mediated with the development of endothelial dysfunction. No studies on the assessment of arterial stiffness and endothelial function after HDCT and autoSCT have been performed before. Aim: To evaluate endothelial function and arterial rigidity parameters by photoplethysmography in patient candidates for HDCT with autoSCT, to identify associated factors and to analyze changes of these parameters over time after HDCT and autoSCT. Materials and methods: In this cohort prospective observational study in 71 patients with verified hemoblastosis (mean age 43.8 ± 12.6 years) we assessed endothelial function and stiffness by photoplethysmography (AngioScan-01, Russia) before and after HDCT with autoSCT. Thirty two (32, 45%) patients had multiple myeloma (ММ), 39 (55%), lymphoproliferative disorders (LPD). We measured the stiffness index (SI), reflection index (RI), augmentation index normalized by heart rate of 75 beats per minute (AIp75) and performed the occlusion test with measurement of occlusion index (ОI) and phase shift (PS). Results: Mean RI in the total study group before HDCT with autoSCT was increased to RI 34.9% [24.5; 50.6], OI decreased to OI 1.5 [1.25; 1.80], and PS module decreased to PS 6.7 ms [3.9; 8.9]. After HDCT with autoSCT the PS module increased to 8.4 ms [5.0; 12.4] (p = 0.001) and OI increased to 1.7 [1.3; 2.2] (p = 0,007), which indicates an improvement in endothelial function. Changes in other parameters of arterial function were non-significant. We also analyzed a selected group of the patients with MM who had higher cardiovascular risk, compared to the LPD patients: they were older (53 vs 36.1 years; p 0.001), had higher rates of arterial hypertension (p 0.001) and diabetes mellitus (p = 0.048). Compared to the LPD patients, the MM patients had higher baseline values of SI (7.5 m/s [7.3; 7.9]), RI (42.9% [32.1; 53.6]), and AIp75 (6.3% [-1.65; 13.8]), indicating higher vascular stiffness. They also had lower PS module values (5.0 ms [2.1; 8.5]). The LPD patients had been more frequently treated with anthracyclines (p 0.001) and radiation (p = 0.002). After HDCT with autoSCT, they had a higher increment of OI, namely, from 1.4 [1.3; 1.8] to 1.7 [1.4; 2.1] (p = 0.003). Conclusion: This study was the first to show a high rate of endothelial dysfunction and vascular stiffness abnormalities in patients with hemoblastoses who were candidates for HDCT with autoSCT. After HDCT with autoSCT, changes of endothelial function and stiffness were multidirectional. Despite a significant improvement, endothelial function parameters were not normalized. We were unable to find any predictors of the abnormalities. Thus, the identified baseline abnormalities in stiffness and endothelial function cannot be a contraindication to HDCT with autoSCT.