Department of Rehabilitation, Uwajima City Hospital.
Department of Cardiology and Geriatrics, Kochi Medical School, Kochi University.
Int Heart J. 2023 Jul 29;64(4):647-653. doi: 10.1536/ihj.23-075. Epub 2023 Jul 14.
Tafamidis improves the prognosis of patients with transthyretin amyloidosis cardiomyopathy (ATTR-CM). Additionally, it delays the decline in exercise tolerance, as observed in the six-minute walking test. However, the changes in cardiopulmonary function over time based on cardiopulmonary exercise tests are unclear. Thus, this preliminary study investigated the changes in exercise tolerance after one year of tafamidis treatment using cardiopulmonary exercise testing. Eight patients with ATTR-CM (average age: 77 years; male: n = 7) underwent cardiopulmonary exercise testing at baseline and after one year of tafamidis treatment. All eight patients completed a one-year follow-up. At baseline, the anaerobic threshold oxygen uptake (AT VO 10.9 ± 1.5) and peak VO (14.3 ± 3.0 mL/kg/minute) indicated relatively favorable exercise capacity; however, the minute ventilation/carbon dioxide production (VE/VCO slope), which indicates effective ventilation, showed poor performance (33.7 ± 12.8). One year after tafamidis treatment, frailty, as assessed by the Clinical Frailty Scale, had progressed in seven of eight patients (88%) (P < 0.01), and AT VO and peak VO were significantly reduced (19.2% and 22.3%, respectively; P < 0.05). The VE/VCO slope and peak O pulse decreased nonsignificantly by approximately 20% (P = 0.47, and P = 0.16, respectively). Further, the structure of the ventricles and atrium and the left ventricle ejection fraction on echocardiography did not change. Thus, exercise tolerance in patients with ATTR-CM was reduced after one year despite tafamidis administration. Not only ATTR-CM progression, but also frailty progression may influence this decrease in exercise tolerance. A comprehensive approach, including tafamidis administration and cardiac rehabilitation, is required for further improvement in the exercise capacity of patients with ATTR-CM.
塔法米迪可改善转甲状腺素淀粉样变性心肌病（ATTR-CM）患者的预后。此外，六分钟步行试验观察到，它可延缓运动耐量下降。然而，基于心肺运动试验的随时间推移的心肺功能变化尚不清楚。因此，本初步研究通过心肺运动试验调查了ATTR-CM 患者在接受塔法米迪治疗一年后运动耐量的变化。8 例 ATTR-CM 患者（平均年龄：77 岁；男性：n = 7）在基线时和接受塔法米迪治疗一年后进行了心肺运动试验。所有 8 例患者均完成了一年的随访。基线时，无氧阈摄氧量（AT VO 10.9 ± 1.5）和峰值 VO（14.3 ± 3.0 mL/kg/min）表明运动能力相对较好；然而，有效通气的分钟通气量/二氧化碳产量（VE/VCO 斜率）表现较差（33.7 ± 12.8）。接受塔法米迪治疗一年后，8 例患者中有 7 例（88%）（P < 0.01）的临床虚弱量表评估的虚弱程度进展，AT VO 和峰值 VO 显著降低（分别为 19.2%和 22.3%；P < 0.05）。VE/VCO 斜率和峰值 O 脉搏分别降低约 20%，但无统计学意义（P = 0.47 和 P = 0.16）。此外，超声心动图检查显示心室和心房结构以及左心室射血分数没有变化。因此，尽管接受了塔法米迪治疗，但 ATTR-CM 患者的运动耐量在一年后仍降低。不仅是 ATTR-CM 的进展，虚弱的进展也可能影响运动耐量的降低。对于改善 ATTR-CM 患者的运动能力，需要采用包括塔法米迪治疗和心脏康复在内的综合方法。
