Adebayo R A, Balogun M O, Akinola N O, Akintomide A O
Department of Medicine, Obafemi Awolowo University Teaching Hospitals Complex, Ile-Ife, Nigeria.
Niger J Med. 2002 Oct-Dec;11(4):170-6.
Most patients with sickle cell anaemia (SCA) show evidence of cardiac dysfunction. This study aimed at clinically and electrocardiographically assessing the exercise capacity of steady state SCA patients using self-paced walking exercise. Forty one (17 males and 24 females) steady state SCA patients between the ages of 15 and 37 years were prospectively studied with 41 age and sex-matched (17 males and 24 females) normal AA controls. All subjects had clinical evaluation, resting 12-lead electrocardiography (ECG), 12 minutes self-paced walking exercise, and were tested for haematological and biochemical abnormalities. The clinical features of the patients reflected a hyperdynamic circulation which was evidenced by faster heart rates, wide pulse pressure, cardiomegaly, loud heart sounds and cardiac murmurs. Non-specific ECG findings were observed in this study. The mean QRS voltage (Sokolow-Lyon criteria) was significantly higher in patients compared to controls (P < 0.05). The mean rate, P wave duration and corrected QT interval of SS patients were significantly higher than the controls. The patients also had a significantly lower mean QRS frontal axis than the controls (P < 0.05) but there was no difference between the two groups in the mean QRS duration and PR interval. There was no abnormal QRS axis in the two groups. The self-paced walking exercise test showed significant limitation of exercise capacity in SCA patients, as evidenced by the significant reduction in speed and distance covered by the patients compared with the controls. While both groups achieved similar post exercise heart rate and systolic BP, the change in heart rate was significantly less in the patients. This study concluded that SCA patients have larger hearts and non-specific ECG changes. They showed significant limitation of exercise capacity with self-paced walking exercise, which was a safe and reproducible measure of cardiac reserve in them.
大多数镰状细胞贫血（SCA）患者表现出心脏功能障碍的迹象。本研究旨在通过自定步速的步行运动，从临床和心电图方面评估稳定期SCA患者的运动能力。对41例年龄在15至37岁之间的稳定期SCA患者（17例男性和24例女性）进行了前瞻性研究，并与41例年龄和性别匹配（17例男性和24例女性）的正常AA对照者进行比较。所有受试者均接受临床评估、静息12导联心电图（ECG）、12分钟自定步速的步行运动，并检测血液学和生化异常情况。患者的临床特征反映出高动力循环，表现为心率加快、脉压增宽、心脏扩大、心音响亮和心脏杂音。本研究观察到非特异性心电图表现。与对照组相比，患者的平均QRS电压（Sokolow-Lyon标准）显著更高（P < 0.05）。SS患者的平均心率、P波时限和校正QT间期显著高于对照组。患者的平均QRS额面电轴也显著低于对照组（P < 0.05），但两组的平均QRS时限和PR间期无差异。两组均无异常QRS电轴。自定步速的步行运动试验显示SCA患者的运动能力明显受限，与对照组相比，患者的速度和行走距离显著降低即可证明。虽然两组运动后的心率和收缩压相似，但患者心率的变化明显较小。本研究得出结论，SCA患者心脏较大且有非特异性心电图改变。他们在自定步速的步行运动中表现出明显的运动能力受限，这是一种安全且可重复的评估其心脏储备的方法。
