Department of Cardiology, Nagoya University Graduate School of Medicine, Nagoya, Japan.
Int J Cardiol. 2013 Jan 20;162(3):234-9. doi: 10.1016/j.ijcard.2011.05.065.
Both peak VO(2) and VE/VCO(2) slope are considered to be useful predictors of cardiovascular events. The left ventricular (LV) response to dobutamine stress testing (DST) also provides useful prognostic information. However, the relationship between these variables has not been fully investigated. Therefore, the aim of this study is to investigate the association between myocardial contractile reserve measured by DST and cardiopulmonary exercise testing (CPX) variables in patients with idiopathic dilated cardiomyopathy (IDCM).
Thirty-eight patients were subjected to CPX as well as cardiac catheterization for measurement of LV pressure. The maximum first derivative of LV pressure (LV dP/dt(max)) was measured at baseline and during dobutamine infusion at incremental doses of 5, 10, and 15 μg kg(-1)min(-1). LV dP/dt(max) at baseline and the percentage increase in LV dP/dt(max) (ΔLV dP/dt(max)) induced by DST served as indices of LV contractility and myocardial contractile reserve, respectively.
Peak VO(2), and VE/VCO(2) slope were 18.6 mL kg(-1)min(-1) and 32.3, respectively. Peak VO(2) was not correlated with LV dP/dt(max) at baseline. However, peak VO(2) was significantly correlated with ΔLV dP/dt(max), and the correlation became more pronounced as the dose of dobutamine was increased. There was no correlation between VE/VCO(2) slope and ΔLV dP/dt(max). Multivariate regression analysis revealed that ΔLV dP/dt(max) was independently correlated with peak VO(2) (p=0.011).
Peak VO(2), but not VE/VCO(2) slope, may reflect myocardial contractile reserve in ambulatory patients with IDCM. This study population is small, and therefore large confirmatory studies are needed.
峰值摄氧量（peak VO₂）和 VE/VCO₂斜率都被认为是心血管事件的有用预测指标。左心室（LV）对多巴酚丁胺应激测试（DST）的反应也提供了有用的预后信息。然而，这些变量之间的关系尚未得到充分研究。因此，本研究旨在探讨特发性扩张型心肌病（IDCM）患者多巴酚丁胺应激测试（DST）测量的心肌收缩储备与心肺运动测试（CPX）变量之间的关系。
38 例患者接受 CPX 检查和心脏导管检查，以测量 LV 压力。在基线和多巴酚丁胺输注时以递增剂量 5、10 和 15 μg kg⁻¹ min⁻¹ 测量 LV 压力的最大一阶导数（LV dP/dt(max)）。LV dP/dt(max)在基线和 DST 诱导的 LV dP/dt(max)的百分比增加（ΔLV dP/dt(max)）分别作为 LV 收缩性和心肌收缩储备的指标。
峰值 VO₂和 VE/VCO₂斜率分别为 18.6 mL kg⁻¹ min⁻¹和 32.3。峰值 VO₂与基线时的 LV dP/dt(max)不相关。然而，峰值 VO₂与 ΔLV dP/dt(max)显著相关，随着多巴酚丁胺剂量的增加，相关性变得更加明显。VE/VCO₂斜率与 ΔLV dP/dt(max)之间没有相关性。多元回归分析显示，ΔLV dP/dt(max)与峰值 VO₂独立相关（p=0.011）。
在 IDCM 的门诊患者中，峰值 VO₂而不是 VE/VCO₂斜率可能反映了心肌收缩储备。本研究人群规模较小，因此需要进行大规模的验证性研究。
Zotero 插件