Post-Graduate Program in Cardiology and Cardiovascular Sciences, Faculdade de Medicina da Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.
Cardiovascular Division, Hospital Moinhos de Vento, Porto Alegre, Brazil.
Heart. 2021 Sep;107(18):1487-1492. doi: 10.1136/heartjnl-2020-317984. Epub 2020 Dec 23.
New York Heart Association (NYHA) functional class plays a central role in heart failure (HF) assessment but might be unreliable in mild presentations. We compared objective measures of HF functional evaluation between patients classified as NYHA I and II in the (ReBIC)-1 Trial.
The ReBIC-1 Trial included outpatients with stable HF with reduced ejection fraction. All patients had simultaneous protocol-defined assessment of NYHA class, 6 min walk test (6MWT), N-terminal pro-brain natriuretic peptide (NT-proBNP) levels and patient's self-perception of dyspnoea using a Visual Analogue Scale (VAS, range 0-100).
Of 188 included patients with HF, 122 (65%) were classified as NYHA I and 66 (35%) as NYHA II at baseline. Although NYHA class I patients had lower dyspnoea VAS Scores (median 16 (IQR, 4-30) for class I vs 27.5 (11-49) for class II, p=0.001), overlap between classes was substantial (density overlap=60%). A similar profile was observed for NT-proBNP levels (620 pg/mL (248-1333) vs 778 (421-1737), p=0.015; overlap=78%) and for 6MWT distance (400 m (330-466) vs 351 m (286-408), p=0.028; overlap=64%). Among NYHA class I patients, 19%-34% had one marker of HF severity (VAS Score >30 points, 6MWT <300 m or NT-proBNP levels >1000 pg/mL) and 6%-10% had two of them. Temporal change in functional class was not accompanied by variation on dyspnoea VAS (p=0.14).
Most patients classified as NYHA classes I and II had similar self-perception of their limitation, objective physical capabilities and levels of natriuretic peptides. These results suggest the NYHA classification poorly discriminates patients with mild HF.
纽约心脏协会（NYHA）功能分级在心衰（HF）评估中起着核心作用，但在轻度表现中可能不可靠。我们比较了 ReBIC-1 试验中被分类为 NYHA I 和 II 的患者之间 HF 功能评估的客观指标。
ReBIC-1 试验纳入了稳定射血分数降低的 HF 门诊患者。所有患者同时接受了协议定义的 NYHA 分级、6 分钟步行试验（6MWT）、N 端脑利钠肽前体（NT-proBNP）水平和患者呼吸困难的自我感知评估，使用视觉模拟量表（VAS，范围 0-100）。
在 188 例 HF 患者中，122 例（65%）基线时被分类为 NYHA I，66 例（35%）为 NYHA II。尽管 NYHA I 级患者的呼吸困难 VAS 评分较低（I 级中位数为 16（IQR，4-30），II 级为 27.5（11-49），p=0.001），但两个等级之间的重叠很大（密度重叠=60%）。NT-proBNP 水平（620pg/mL（248-1333）与 778pg/mL（421-1737），p=0.015；重叠=78%）和 6MWT 距离（400m（330-466）与 351m（286-408），p=0.028；重叠=64%）也存在类似的情况。在 NYHA I 级患者中，19%-34%有一个 HF 严重程度标志物（VAS 评分>30 分、6MWT<300m 或 NT-proBNP 水平>1000pg/mL），6%-10%有两个标志物。功能分级的时间变化并没有伴随着呼吸困难 VAS 的变化（p=0.14）。
大多数被分类为 NYHA I 和 II 级的患者对自身限制、客观身体能力和利钠肽水平的自我感知相似。这些结果表明，NYHA 分级不能很好地区分轻度 HF 患者。
