Department of Cardiology, Ziekenhuis Oost-Limburg, Schiepse Bos 6, 3600, Genk, Belgium; Doctoral school for Medicine and Life Sciences, Hasselt University, Diepenbeek, Belgium.
Eur J Heart Fail. 2015 Mar;17(3):320-8. doi: 10.1002/ejhf.217. Epub 2014 Dec 30.
To study pulmonary vascular response patterns to exercise in heart failure with reduced ejection fraction (HFrEF) and pulmonary hypertension (PH).
In this prospective single-centre cohort study, consecutive symptomatic HFrEF patients (n = 40) with mean pulmonary arterial pressure (MPAP) ≥25 mmHg, pulmonary artery wedge pressure (PAWP) >15 mmHg, and cardiac index <2.5 L/min.m(2) , received protocol-driven titrated sodium nitroprusside (SNP) and diuretics to reach mean arterial blood pressure 65-75 mmHg and PAWP ≤15 mmHg. Patients performed symptom-limited supine bicycle testing under continued SNP administration. Afterwards, SNP was gradually withdrawn, renin-angiotensin system blockers uptitrated, and hydralazine added to maintain haemodynamic targets. Subsequently, bicycle testing was repeated. Patients presented with pulmonary vascular resistance (PVR) = 3.8 ± 1.4 Wood Units at rest, decreasing to 2.9 ± 0.9 Wood Units after decongestion, with PH was completely reversed (MPAP <25 mmHg) in 22%. From rest to maximal exercise, the cardiac index did not change significantly (P = 0.334 under SNP; P-value = 0.552 under oral therapy). A dynamic exercise-induced PVR increase >3.5 Wood Units was noted in 19 patients (48%) under oral therapy vs. five (13%) under SNP. Such exercise-induced PVR increase was associated with a 33% relative decrease in right ventricular stroke work index (P = 0.037).
Even after thorough decongestion and under continuous afterload reduction, PH secondary to HFrEF is completely reversible in only a minority of patients. Others demonstrate an exercise-induced PVR increase, associated with impaired right ventricular stroke work, which might be ameliorated by nitric oxide donor support.
研究射血分数降低的心力衰竭（HFrEF）合并肺动脉高压（PH）患者运动时的肺血管反应模式。
在这项前瞻性单中心队列研究中，连续入组 40 例有症状的 HFrEF 患者，平均肺动脉压（MPAP）≥25mmHg，肺动脉楔压（PAWP）＞15mmHg，心指数＜2.5L/min.m²，给予硝普钠（SNP）和利尿剂进行滴定以达到平均动脉血压 65-75mmHg 和 PAWP≤15mmHg。患者在持续给予 SNP 下进行症状限制的仰卧位踏车运动。然后，逐渐撤去 SNP，增加肾素-血管紧张素系统阻滞剂，并加用肼屈嗪以维持血液动力学目标。随后重复踏车运动。患者静息时肺血管阻力（PVR）为 3.8±1.4 伍德单位，充血消退后降至 2.9±0.9 伍德单位，22%的患者 PH 完全逆转（MPAP＜25mmHg）。从静息到最大运动，心指数在 SNP 下无显著变化（P=0.334；口服治疗时 P 值=0.552）。口服治疗时 19 例（48%）患者在运动时出现 PVR 增加＞3.5 伍德单位，而 SNP 下为 5 例（13%）。这种运动诱导的 PVR 增加与右心室每搏功指数相对降低 33%相关（P=0.037）。
即使经过彻底的充血消退和持续的后负荷降低，HFrEF 继发 PH 也只有少数患者可完全逆转。其他患者则表现出运动诱导的 PVR 增加，伴有右心室每搏功受损，这可能通过一氧化氮供体支持得到改善。
