研究显示氯沙坦对马凡综合征有效

阿姆斯特丹——欧洲心脏病学会(ESC)年会上发布的一项为期3年的随机临床试验显示，每日给予马凡综合征成年患者氯沙坦治疗可显著降低主动脉根部的扩张速度。该试验结果同时在线发表在《欧洲心脏杂志》上(Eur. Heart J. 2013 [doi:10.1093/eurheartj/eht334])。


Maarten Groenick医生

马凡综合征是一种累及多个器官系统的遗传性结缔组织疾病。其结局主要取决于主动脉并发症，包括主动脉扩张、动脉瘤形成和急性主动脉夹层。患者往往身材较高、四肢较长和具有特征性的细长手指。马凡综合征的患病率估计为1/5,000，但Groenink医生认为这种综合征的实际患病率更高。

COMPARE（科素亚用于减少马凡综合征患者的主动脉扩张）试验从荷兰的所有4家马凡中心纳入了218例患者。将患者随机分组，在β受体阻滞剂标准治疗基础上追加或不追加目标剂量为100 mg/d的口服氯沙坦治疗。氯沙坦组约有半数患者无法耐受受体阻滞剂基础上追加全量的氯沙坦治疗；这些患者维持氯沙坦治疗的剂量为50 mg/d。在入组时和前瞻性随访3年后，使用MRI测定主动脉根部直径。

结果显示，氯沙坦组的主动脉扩张速度显著低于接受和未接受主动脉根部置换手术的对照者，阿姆斯特丹医学中心的心脏病专家Groenink医生报告。氯沙坦组无1例患者发生主动脉夹层，对照组发生2例主动脉夹层。两组接受择期主动脉置换手术的患者数相似。氯沙坦组患者的血压较低，但血压与主动脉扩张速度不相关。



Groenink医生推测，氯沙坦对马凡综合征患者产生益处的主要机制为遏制转化生长因子-的过度表达，而转化生长因子-β可使主动脉壁中层结构变薄弱。尚不清楚氯沙坦的益处是这种药物所特有的，还是血管紧张素Ⅱ受体拮抗剂所共有的，但他认为后者的可能性较大。

“我认为，马凡综合征对主动脉壁的不良作用是由于肌原纤维蛋白缺陷造成的，但同时也受到心脏跳动导致的周期性应力的消磨。因此可以推测，越早开始治疗，结果就越好。”

COMPARE试验获得了荷兰心脏协会的资助。Groenink医生披露无相关利益冲突。

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By: BRUCE JANCIN, Cardiology News Digital Network

AMSTERDAM – Daily losartan significantly slowed the aortic root dilatation rate in adults with Marfan syndrome in a 3-year randomized clinical trial.

"I think we can be positive about this treatment. We can now recommend losartan in clinical practice," Dr. Maarten Groenink said at the annual congress of the European Society of Cardiology.

There were no aortic dissections in the losartan group and two in the control arm. Elective aortic replacement surgery was performed in a similar number of patients in both groups.

Blood pressure was lower in the losartan group, yet blood pressure didn’t correlate with the aortic dilatation rate. Dr. Groenink speculated that losartan’s chief mechanism of benefit in Marfan syndrome is its ability to curb overexpression of transforming growth factor-beta, which weakens the structure of the media layer of the aortic wall.

Dr. Groenink said it’s unknown whether losartan’s benefits are specific to that drug or are a class effect obtainable with other angiotensin II receptor antagonists, though he suspects it’s a class effect.

Ongoing clinical trials are evaluating losartan in children and adolescents with Marfan syndrome, he said, adding that there is a solid rationale for beginning treatment as early in life as possible.

"I believe the adverse effects on the aortic wall in Marfan syndrome are caused by the fibrillin defect but also by wear and tear due to cyclic stress by the beating heart. So you can hypothesize that the earlier you start treatment, the better the results," he explained.

Marfan syndrome is a genetic connective tissue disorder affecting multiple organ systems. The prognosis is mainly determined by the aortic complications, including dilatation, aneurysm formation, and possible acute dissection. Affected individuals tend to be tall, long-limbed, and have distinctively long, thin fingers. The prevalence of Marfan syndrome has been estimated at 1 in 5,000, but Dr. Groenink suspects the syndrome may actually be more common than that.

Simultaneous with Dr. Groenink’s presentation at the ESC, the COMPARE results were published online (Eur. Heart J. 2013 [doi:10.1093/eurheartj/eht334]).

The COMPARE trial was funded by the Dutch Heart Association. Dr. Groenink reported having no relevant financial interests.

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COMPARE is a very important study whose results are going to mean a paradigm shift for the management of Marfan syndrome.

It is intriguing to consider that the benefits of losartan might possibly also extend to patients with thoracic aortic disease in general, a worthy topic for future investigation.

Dr. John Gordon Harold is with Cedars-Sinai Heart Institute, Los Angeles, and president of the American College of Cardiology. He had no relevant financial disclosures.