The purpose of this study was to assess the predictors, clinical correlates, and prognostic value of diurnal CSR in upright position.
Outpatients with systolic HF underwent a comprehensive evaluation, including short-term respiratory monitoring with a head-up tilt test to investigate the presence of upright CSR, assessment of chemoreflex response to hypoxia and hypercapnia, and 24-h cardiorespiratory recording. At follow-up, cardiac death was considered as the endpoint.
Of 574 consecutive patients (left ventricular ejection fraction 32 ± 9%; age 65 ± 13 years; 80% men), 195 (34%) presented supine CSR only, 82 (14%) presented supine and upright CSR, and 297 patients (52%) had normal breathing. Patients with upright CSR had the greatest apnea-hypopnea and central apnea index (at daytime and nighttime), the worst hemodynamic profile and exercise performance, increased plasma norepinephrine and N-terminal pro-B-type natriuretic peptide, and chemosensitivity to hypercapnia, which was the only independent predictor of upright CSR (odds ratio: 3.96; 95% confidence interval [CI]: 1.45 to 10.76; p = 0.007 vs. normal breathing; odds ratio: 4.01; 95% CI: 1.54 to 10.46; p = 0.004 vs. supine CSR). At 8-year follow-up, patients with upright CSR had the worst outcome (log-rank = 14.05; p = 0.001) and the presence of upright CSR independently predicted 8-year cardiac death (hazard ratio: 2.39; 95% CI: 1.08 to 5.29; p = 0.032).
Upright CSR in HF patients is predicted by increased chemosensitivity to hypercapnia and is associated with worse clinical conditions and with a greater risk of cardiac death.
这项研究的目的是评估预测因子,临床相关因素,直立体位昼夜CSR的预后价值。
对收缩期HF门诊患者进行了综合评估,包括短期呼吸监测与平头倾斜测试,以调查直立CSR的存在,对缺氧和高碳酸血症的化学反射反应的评估,和24小时心肺记录。在后续行动中,心脏死亡被认为是终点.
在574例连续患者中(左心室射血分数32±9%;年龄65±13岁;80%为男性),195(34%)仅提供仰卧CSR,82(14%)呈现仰卧和直立CSR,297例患者(52%)呼吸正常。直立CSR患者的呼吸暂停低通气和中枢呼吸暂停指数(白天和夜间)最大,最差的血液动力学特征和运动表现,血浆去甲肾上腺素和N末端B型利钠肽前体升高,和对高碳酸血症的化学敏感性,这是直立CSR的唯一独立预测因子(优势比:3.96;95%置信区间[CI]:1.45至10.76;p=0.007vs.正常呼吸;比值比:4.01;95%CI:1.54至10.46;p=0.004vs.仰卧CSR)。在8年的随访中,直立CSR患者的结局最差(log-rank=14.05;p=0.001),直立CSR的存在独立预测了8年心源性死亡(风险比:2.39;95%CI:1.08~5.29;p=0.032).
HF患者的直立CSR可通过对高碳酸血症的化学敏感性增加来预测,并且与更差的临床状况和更高的心脏死亡风险相关。