Alterations in heart rate variability in patients with peripheral arterial disease requiring surgical revascularization have limited association with postoperative major adverse cardiovascular and cerebrovascular events

PLoS One. 2018 Sep 13;13(9):e0203519. doi: 10.1371/journal.pone.0203519. eCollection 2018.

Abstract

Objective: Obstructive sleep apnea (OSA) is common in peripheral arterial disease (PAD) and associates with high mortality after surgery. Since abnormal heart rate variability (HRV) is predictive of postoperative complications, we investigated the relations of HRV with PAD, OSA and major adverse cardiovascular and cerebrovascular events (MACCE).

Materials and methods: Seventy-five patients (67±9 years) scheduled for sub-inguinal revascularization and 15 controls (63±6 years) underwent polysomnography and HRV analyses. OSA with an apnea-hypopnea index (AHI) ≥20/hour was considered significant. HRV was measured during wakefulness, S2, S3-4 and rapid eye movement (REM) sleep with time and frequency domain methods including beat-to-beat variability, low frequency (LF) and high frequency (HF) power, and detrended fluctuation analysis (DFA). MACCE was defined as cardiac death, myocardial infarction, coronary revascularization, hospitalized angina pectoris and stroke.

Results: Thirty-six patients (48%) had AHI≥20/hour. During follow-up (median 52 months), 22 patients (29%) suffered a MACCE. Compared to controls, fractal correlation of HRV (scaling exponent alpha 1 measured with DFA) was weaker during S2 and evening wakefulness in all subgroups (+/-AHI≥20/hour, +/-MACCE) but only in patients with AHI≥20/hour during morning wakefulness. The LF/HF ratio was lower in all subgroups during S2 but only in patients with AHI ≥20/hour during evening or morning wake. In the covariance analysis adjusted for age, body mass index, coronary artery disease and PAD duration, the alpha 1 during morning wakefulness remained significantly lower in patients with AHI≥20/hour than in those without (1.12 vs. 1.45; p = 0.03). Decreased HF during REM (p = 0.04) and S3-4 sleep (p = 0.03) were predictive of MACCE. In analyses with all sleep stages combined, mean heart rate as well as very low frequency, LF, HF and total power were associated with OSA of mild-to-moderate severity (AHI 10-20/hour).

Conclusions: HRV is altered in patients with PAD. These alterations have a limited association with OSA and MACCE.

Publication types

  • Clinical Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Cerebrovascular Disorders* / etiology
  • Cerebrovascular Disorders* / physiopathology
  • Female
  • Follow-Up Studies
  • Heart Rate*
  • Humans
  • Male
  • Middle Aged
  • Peripheral Arterial Disease* / physiopathology
  • Peripheral Arterial Disease* / surgery
  • Polysomnography*
  • Postoperative Complications / physiopathology*
  • Sleep Apnea, Obstructive* / physiopathology
  • Sleep Apnea, Obstructive* / surgery
  • Vascular Surgical Procedures / adverse effects*

Grants and funding

This study was supported by Clinical Research Fund of the Hospital District of Southwest Finland (project numbers 13094 and 13176) to TL, http://www.vsshp.fi/en/tutkijoille/tutkimustoimisto/Pages/default.aspx; Tekes: Finnish Funding Agency for Innovation/GE Healthcare (2753/31/2005) to TL, https://www.tekes.fi/en/; and Instrumentarium Science Foundation (no grant number available) to TL, http://www.instrufoundation.fi/en.php. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.