腹部動脈瘤破裂使用血管內修補的效果比開腹手術更好
作者：Thomas R. Collins
出處：WebMD醫學新聞
January 20, 2010 (佛州好萊塢) — 根據發表於第22屆血管內治療國際研討會的一篇荷蘭研究結果，相較於開腹手術，使用微創血管內方式治療破裂的腹部主動脈瘤，可以降低死亡略超過25%。
這些研究者還發現一個生物標記，可以更容易找出血管內修補案例的裂隙處，而不需要以電腦斷層(CT)進行掃描。
在其他研究中已經顯示，使用支架進行的血管內治療對於破裂的腹主動脈瘤緊急案例有效，但是，荷蘭的研究者報告指出，他們認為這是第一個實際比較開腹手術和血管內修補結果的研究。
荷蘭希倫的Atrium醫學中心進行的研究中，治療6個月後，使用血管內修補治療的25個病患有7人(28%)死亡，開腹手術治療的33人有18人(55%)死亡(P< .05)。
研究者之一、Atrium醫學中心外科住院醫師Jan Ten Bosch在發表時表示，急診EVAR [血管內動脈瘤修補(endovascular aneurysm repair)]是適合EVAR的破裂腹部動脈瘤病患的優先治療選項。
Ten Bosch醫師指出，研究顯示，多達80%的病患在腹部主動脈瘤破裂時奪走生命。
他指出，之前評估血管內方法的研究有明顯的取樣偏差，只有選最適合的病患。
他表示，解剖狀態較佳的病患、以及血液動力學狀態較佳的病患被納入EVAR組，我們的目標是比較對於所有接受電腦斷層血管攝影掃描、適合EVAR病患的緊急腹部動脈瘤修補。
另外有兩篇回顧探討以掃描確定適合EVAR的病患。
他表示，病患被視為適合EVAR是「假隨機」；只有有待命的血管內外科醫師且可以執行該手術時，才會進行血管內方法，如果沒有醫師可以進行，就採用開腹手術。
血管內治療方式的病患，其平均住院天數為8天，開腹手術病患的平均住院天數是18天。
血管內修補腹部主動脈瘤的一個問題是，有十分之一會發生裂隙，傳統上只有在追蹤時使用昂貴的CT血管攝影才可以發現這些裂隙。
Atrium 醫學中心的研究團隊發現一個可能可以無須掃描就辨識裂隙的生物標記，出現基質金屬蛋白酶9(MMP-9)表示可以預測主動脈裂隙。
研究的37個病患中，17個有裂隙的病患全部都有明顯較高的MMP-9值，只有1個沒有裂隙但是有較高的MMP-9值。
Ten Bosch醫師解釋，這意味著只需要簡單的驗血就可以確定是否有裂隙，他表示，Atrium醫學中心的研究團隊希望開始進行前瞻性多中心試驗來檢測MMP-9的預測價值。
來自佛羅里達邁阿密Baptist心血管研究中心、主持該段會議的Constantino Pena醫師表示，這些研究令人印象深刻。
Pena醫師向Medscape Radiology表示，他們探討了血管內修補的2個非常重要的議題。
他表示，藉由更多研究，使用MMP-9可能會是重大突破，我認為，我們都希望這些病患的放射檢測方式可以減少。
這些研究未接受商業支持。Ten Bosch醫師與Pena醫師皆宣告沒有相關財務關係。
第22屆血管內治療國際研討會(ISET)：摘要45與100。發表於2010年1月18日。
Endovascular Repair of Ruptured Abdominal Aneurysms Yields Better Outcome Than Open Surgery
By Thomas R. Collins
Medscape Medical News
January 20, 2010 (Hollywood, Florida) — Repair of ruptured abdominal aortic aneurysms with a minimally invasive endovascular approach is associated with a greater than 25% reduction in mortality, compared with an open surgery approach, according to the results of a Dutch study reported here at the 22nd Annual International Symposium on Endovascular Therapy.
The same researchers have also found a biomarker that might make it easier to find leaks involved in endovascular repair cases without computed tomography (CT) scanning.
Endovascular treatment with stent grafts has been shown in other studies to be effective in emergency cases of ruptured abdominal aortic aneurysm, but this study is believed to be the first that actually compares results in patients deemed suitable for either open surgical repair or endovascular repair, the Dutch team reported here.
After 6 months, 7 of the 25 patients (28%) treated with the endovascular approach had died, compared with 18 of the 33 patients (55%) treated with open surgical repair in a study performed at Atrium Medical Center in Heerlen, the Netherlands (P?< .05).
"It suggests that emergency EVAR [endovascular aneurysm repair] is the preferred treatment option for patients with an EVAR-suitable ruptured abdominal aneurysm," investigator Jan Ten Bosch, MD, a surgery resident at Atrium, said during the presentation.
Studies have shown that as many as 80% of patients die when their abdominal aortic aneurysms rupture, Dr. Ten Bosch pointed out.
Previous studies evaluating the endovascular approach have had significant selection bias, with only the most ideal patients being chosen, he noted.
"Patients with a favorable anatomy?.?.?. and patients with a better hemodynamic status are recruited for the EVAR group," he said. "The objective of our study was to compare emergency abdominal aneurysm repair in all EVAR-suitable patients?.?.?. who underwent [computed tomography angiography] scanning."
Two separate reviews of the scans were done to determine that the patients were fit for EVAR.
Patients who were deemed eligible for EVAR were "pseudorandomized," he said; the endovascular approach was used only when the endovascular surgeon was on-call and available to do the procedure. When that surgeon wasn't available, open surgery was performed.
The endovascular patients had an average hospital stay of 8 days, whereas the open surgery patients had an average stay of 18 days.
A problem with endovascular repair of abdominal aortic aneurysms is that 1 in 10 develops leaks, and the leaks traditionally have been found only with expensive CT angiography scans performed during follow-up.
The Atrium team found a possible biomarker that can identify the leaks without such scanning. The presence of matrix metalloproteinase-9 (MMP-9) was shown to be a predictor of aortic leaks.
In a study of 37 patients, all 17 with a leak had significantly higher MMP-9 levels, whereas only 1 who did not have a leak had higher MMP-9 levels.
That could mean that, eventually, a simple blood test might be all that is needed to determine whether there is leakage, Dr. Ten Bosch explained. He said that Atrium researchers hope to start a prospective multicenter trial to test the predictive value of MMP-9.
Constantino Pena, MD, an interventional radiologist at the Baptist Cardiac Vascular Institute in Miami, Florida, who moderated the session, said the studies were impressive.
"He hits on 2 very important topics in terms of endovascular repair," Dr. Pena told Medscape Radiology.
He said that with more study, the use of MMP-9 could be a major breakthrough. "I think we all want to reduce the radiation surveillance of these patients," he added.
The studies did not receive commercial support. Dr. Ten Bosch and Dr. Pena have disclosed no relevant financial relationships.
22nd Annual International Symposium on Endovascular Therapy (ISET): Abstracts?45 and 100. Presented January?18, 2010.
