MedWire News: The angiotensin receptor blocker (AR irbesartan does not improve outcomes in well-treated patients with heart failure (HF) and a preserved ejection fraction (EF), a major trial has shown.
Medwire新闻：一个主要实验表明，血管紧张素阻断剂依贝沙坦不能改善得到良好治疗及射血分数正常的心衰患者的预后。
I-PRESERVE is the largest trial conducted in patients with this form of HF and is consistent with two earlier trials in detecting neither benefit nor harm from adding an ARB to optimal medical therapy in patients with the clinical syndrome of HF but an EF ≥45%.I-PRESERVE试验是一个最大的实施在由心衰病人组成的试验，贯穿其中的两个早期试验证明，在临床表现为心衰但EF值大于45%的病人身上添加血管紧张素受体阻断剂优化治疗既不获益也无伤害。
The I-PRESERVE (Irbesartan in HF with preserved EF) trial was presented by Peter Carson (Georgetown University and Washington DC Veterans Affairs Medical Center, Washington, DC) at the American Heart Association 2008 Scientific Sessions in New Orleans, Louisiana
I-PRESERVE试验（在射血分数正常的心衰患者依贝沙坦的应用）由Peter Carson（华盛顿哥伦比亚特区退伍军人医药中心和乔治敦大学）在路易斯按纳州，新奥尔良由美国心脏病协会举办的2008年科学会议中提出。
The trial focused on HF with preserved EF (also known as diastolic HF), a form of the syndrome that accounts for around 50% of all cases of HF but is little-studied and poorly understood. It affects mainly women and older patients and usually has a hypertensive etiology; despite carrying substantial morbidity and mortality there is no effective evidence-based treatment.
该实验重点为保留EF值的心衰患者（即舒张性心衰），组成为所有心衰患者EF值在50%左右的，此类病例的研究不多，理解不深。这会涉及多数女性及常常合并高血压的。尽管在循证医学上其患病率和死亡率无明显差异。
The trial enrolled 4128 patients aged ≥60 years, in New York Heart Association Class II–IV, and with an EF ≥45%. All patients had either a recent hospitalization for HF or corroborative evidence of HF, such as pulmonary congestion or left-ventricular hypertrophy. They were randomized to receive irbesartan 300 mg/day or placebo and followed-up for a median of 49.5 months.
该实验录入年龄大于等于60岁的老年患者4128人，纽约心脏协会心功能分级II–IV,射血分数大于等于45%，所有患者有新近因心衰而住院治疗或确定为心衰，如肺淤血或左室肥大。他们随机分别接受依贝沙坦300mg/天，及安慰剂组，平均随访49.5个月。
The subjects were well-treated at baseline, said Carson, and spironolactone and beta-blocker use increased markedly during the study period. Less than one-third of subjects were receiving an angiotensin converting enzyme inhibitor at baseline, although this rose to around 40% by the end of follow-up.
Carson说，这些受试者有良好的基础治疗，使用安体舒通和β受体阻滞剂在研究期间明显增加。不到三分之一的受试者接受一种血管紧张素转换酶抑制剂作为基础用药，尽管在结束随访时接近40%。
The study’s primary endpoint was death or cardiovascular (CV) hospitalization, defined as hospitalization for HF, myocardial infarction (MI), stroke, or arrhythmia. This did not differ between the groups, with a nonsignificant hazard ratio of 0.95 (p=0.35).
该研究主要终点事件是死亡或因心血管事件入院接受治疗、明确为因心衰而住院、、脑卒中或心律失常。组间无明显差异。发生风险概率为0.95(p=0.35).
Subgroup analyses found no indication of a treatment benefit in any patient group, said Carson. Furthermore, all secondary endpoints – including death, CV death, HF death/HF hospitalization, CV death/MI/stroke, six-minute hall-walk, and NT-pro-BNP – were neutral, indicating no significant effect of irbesartan as compared with placebo.
Carson认为，亚组分析表明，没有那个组有治疗更加获益的迹象。并且，所有的次要终点事件，包括死亡死亡或因心血管事件死亡/入院、心衰死亡/入院、心血管事件死亡/心肌梗死/脑卒中、六分钟步行、及脑钠肽测定结果均是中立的，在依贝沙坦及安慰剂组之间比较无显著性差异。
Irbesartan therapy was well tolerated and was not associated with an excess of any side effects.
依贝沙坦治疗依从性良好，无过度副作用。
“For this large group of patients constituting up to half of all HF patients, there continues to be no specific evidence-based therapy,” Carson concluded. “In order for this field to move forward, a better understanding is needed of the mechanisms underlying this syndrome and additional potential targets for treatment.”
Carson总结说，因为这组患者由包括所有心衰患者的一半所组成，持续使用该药没有特殊循证学意义，为了促进该领域的前进，需要对隐藏在该综合症下心脏结构的改变有更深的理解，以及增加潜在的治疗靶点。
I-PRESERVE was discussed by Maggie Redfield (Mayo Clinic, 200 First St. SW, Rochester, MN 55), who said it was a “carefully designed and well-performed study with unambiguous findings”.
Maggie Redfield论述了I-PRESERVE试验，她认为该实验是细致设计加上良好的执行得出了一个明确的结果。
She said the results of I-PRESERVE echo those of the CHARM-PRESERV and PEP-CHF in demonstrating no benefit of add-on ARBs in patients with HF and a preserved EF. ARBs remain useful for controlling blood pressure in these patients, she added.
她说I-PRESERVE结果响应了CHARM-PRESERVED和 PEP-CHF的证明，在保留了EF值的心衰患者中添加血管紧张素受体抑制剂是不能获益的。她补充说明，在这些患者中血管紧张素受体抑制剂可以用于控制血压。