Andrade G N, Rodrigues T, Takada J Y, Braga L M, Umeda I I K, Nascimento J A, Pereira-Filho H G, Grupi C J, Salemi V M C, Jacob-Filho W, Cahalin L P, Mansur A P, Bocchi E A, Nakagawa N K
Physical Therapy Department, University of São Paulo Medical School, São Paulo, SP, Brazil.
Heart Institute (InCor), University of São Paulo Medical School, São Paulo, SP, Brazil.
Physiotherapy. 2022 Mar;114:77-84. doi: 10.1016/j.physio.2021.03.012. Epub 2021 Mar 22.
To determine whether the time for peak exercise heart rate to return to resting heart rate after the 6-minute walk test (6MWT) can predict cardiac events in patients with heart failure (HF) within 2 years.
Prospective cohort study.
HF outpatient facility at a tertiary teaching hospital.
Seventy-six patients with HF, New York Heart Association functional classification II and III, and left ventricular ejection fraction <50%.
Patients used a heart rate monitor to measure the time for peak exercise heart rate to return to resting heart rate after the 6MWT. Data were analysed using Polar Pro-Trainer 5 software (Kempele, Finland). Patients were followed for >2 years for cardiac events (hospitalisations and death).
Thirty-four patients had cardiac events during the 2-year follow-up period. However, there was a significant difference in the time to return to resting heart rate between the groups with and without cardiac events {with 3.6 (SD 1.1) vs without 2.8 (SD 1.1) minutes; mean difference of 0.79 (95% confidence interval (CI) of the difference 0.28 to 1.28; P=0.003}. No significant differences between patients with and without cardiac events were found for mean walking distance, mean heart rate recovery at 1minute and mean heart rate recovery at 2minutes. The receiver operating curve discriminated between patients with and without cardiac events (área under the curve 0.71, 95% CI 0.61 to 0.81; P<0.001). Using logistic regression analysis, prolonged time to return to resting heart rate (≥3minutes) independently increased the risk for cardiac events 6.9-fold (95% CI 2.34 to 20.12; P<0.001). The Kaplan-Meier curve showed more cardiac events in patients with prolonged time to return to resting heart rate (P=0.028).
Prolonged time to return to resting heart rate (≥3minutes) after the 6MWT was an independent predictor of cardiac events in patients with HF.
确定6分钟步行试验（6MWT）后运动峰值心率恢复到静息心率的时间是否能预测心力衰竭（HF）患者2年内的心脏事件。
前瞻性队列研究。
一家三级教学医院的HF门诊设施。
76例HF患者，纽约心脏协会功能分级为II级和III级，左心室射血分数<50%。
患者使用心率监测仪测量6MWT后运动峰值心率恢复到静息心率的时间。使用Polar Pro-Trainer 5软件（芬兰凯姆佩莱）分析数据。对患者进行>2年的随访以观察心脏事件（住院和死亡）。
34例患者在2年随访期内发生心脏事件。然而，有心脏事件组和无心脏事件组恢复到静息心率的时间存在显著差异{分别为3.6（标准差1.1）分钟和2.8（标准差1.1）分钟；平均差异为0.79（差异的95%置信区间为0.28至1.28；P = 0.003}。有心脏事件组和无心脏事件组在平均步行距离、1分钟时的平均心率恢复和2分钟时的平均心率恢复方面未发现显著差异。受试者工作特征曲线区分了有心脏事件组和无心脏事件组（曲线下面积为0.71，95%置信区间为0.61至0.81；P < 0.001）。使用逻辑回归分析，恢复到静息心率的时间延长（≥3分钟）使心脏事件风险独立增加6.9倍（95%置信区间为2.34至20.12；P < 0.001）。Kaplan-Meier曲线显示恢复到静息心率时间延长的患者发生更多心脏事件（P = 0.028）。
6MWT后恢复到静息心率的时间延长（≥3分钟）是HF患者心脏事件的独立预测因素。
