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Abstract 12661: Respiratory Muscle Weakness is an Independent Determinant for Decreased Parasympathetic Activity in Patients With Chronic Heart Failure

2016; Lippincott Williams & Wilkins; Volume: 134; Issue: suppl_1 Linguagem: Inglês

10.1161/circ.134.suppl_1.12661

1524-4539

Nobuaki Hamazaki, Takashi Masuda, Kentaro Kamiya, Ryota Matsuzawa, Kohei Nozaki, Shinya Tanaka, Yumi Kamada, Kanae Yabu, Takeshi Nakamura, Minoru Tabata, Emi Maekawa, Chiharu Noda, Minako Yamaoka‐Tojo, Junya Ako,

Heart Rate Variability and Autonomic Control

Background: Decreased parasympathetic activity and respiratory muscle weakness are known as indicators for poor outcome in patients with chronic heart failure (CHF). Although the effect of respiratory modulation on autonomic system has been documented, the relationship between respiratory muscle strength and parasympathetic activity is still unknown. The present study aimed to investigate the influence of respiratory muscle weakness on parasympathetic activity in CHF patients. Methods: We studied 254 patients with compensated CHF (60.3±12.0 years, 202 males) who received cardiac rehabilitation during hospitalization and after hospital discharge. Maximal inspiratory pressure (PI max ) was measured as a respiratory muscle strength using a spirometer 2 months after the discharge. Patients received symptom limited cardiopulmonary exercise test (CPX) and then heart rate recovery (HRR) during the first minute after the cessation of CPX was assessed as a parasympathetic activity. HRR of ≤18 /min was determined as a decreased parasympathetic activity. Patients were divided into three groups based on the tertile of PI max : low PI max (PI max <58.7 cmH 2 O), moderate PI max (58.7≤ PI max <83.6 cmH 2 O) and high PI max (PI max ≥83.6 cmH 2 O) groups. We compared the HRR among the three groups and identified the determinant for HRR of ≤18 /min using a multivariate logistic regression analysis. Results: Ninety-four patients among the studied patients, 47 in the low PI max group, 28 in the moderate PI max group and 19 in the high PI max group, showed HRR of ≤18 /min. The low PI max group showed significantly lower HRR as compared with the other two groups (P=0.001 and <0.001, respectively). The multivariate logistic regression analysis identified the PI max as a significant independent determinant for HRR of ≤18 /min (odds ratio=0.832, P=0.008, Figure). Conclusion: Respiratory muscle weakness was an independent determinant for decreased parasympathetic activity in patients with CHF.