Intravascular Ultrasound for the Evaluation of Malperfusion Syndrome in the Setting of Acute Aortic Dissection: A Pilot Study.
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 50
- 试验地点
- 1
- 主要终点
- Primary Safety Endpoint
研究概览
简要总结
Aortic dissection is a life-threatening condition caused by a tear in the internal layer of major artery wall (aorta) that carries blood to all body organs, resulting in separation of the aortic wall layers (dissection). The dissected aorta compromises blood flow to any organ, and eventually leads to organ damage (Malperfusion Syndrome).
Our goal in this project is to use Intravascular Ultrasound (IVUS) to have real time assessment and confirm any evidence of malperfusion syndrome in the setting of aortic dissection after repairing the original aortic tear. IVUS is a small ultrasound (sound waves) wand that is attached to the top of a thin tube. This tube is inserted into the aorta from the groin. This device takes pictures of the aorta and its major branches, to identify problems with blood flow. Having this real-time and dynamic assessment will help to identify any malperfused organs before leaving the operating room and allow us to address the malperfusion syndrome as quickly as possible to limit complications. Without this technique, identifying the problem can take several days after surgery at which point there can be irreversible complications.
详细描述
Acute Type A Aortic Dissection
A Debakey acute type A aortic dissection (ATAAD) represents a lethal condition with a risk of mortality of 1% per hour and up to nearly 50% in first 48 hours if left untreated.1, 2 Traditional surgical teaching has always involved emergent repair of the proximal aortic with resection and replacement of the intima entry tear and aneurysmal tissue within the ascending aorta. This approach addresses obviates the risk of aortic rupture, proximal extension into the coronary arteries, cardiac tamponade and aortic valve insufficiency, all of which lead to mortality. However, as expertise in the field progress evidence is emerging that dealing with only the proximal extent of the dissection may still leave a significant portion of patients at risk for complications from an inability to identify and treat end-organ malperfusion.3 At Western University and London Health Sciences center our mortality rate for patients presenting the ATAAD has been reporter at 20.0%4, and is similar to that reported by the International Registry of Acute aortic Dissection (IRAD) database, with mortality rates between 16.2 and 27.4%.5,6
Malperfusion Syndrome and Aortic Rupture In the 2018 Circulation paper published by Yang et al. the University of Michigan group outline the treatment strategy for ATAAD.
In this study, all patients with an ATAAD presenting with malperfusion, but without signs of aortic rupture or cardiac tamponade, were treated first with endovascular revascularization followed by delayed open aortic repair.3 The authors report that in the second decade of their experience with this treatment model, the overall mortality dropped to 10.7%.3 When compared to our local data and that published by the IRAD group, it would appear that there are significant improvements that can be made for the treatment of these individuals. The authors report that roughly 1/3 of all patients presented with some form of malperfusion syndrome and that in this group, 87% of the deaths were attributed to organ failure from malperfusion even after fenestration and stenting. Conversely there was only a 4% risk of aortic rupture following fenestration and stenting prior to open surgical repair in this group.3 This would indicate that malperfusion is a significant cause of morbidity and mortality in these patients maybe even more so than the risk of aortic rupture in selective patients but in order to improve our outcomes, we need a better way to assess static and dynamic changes that cause malperfusion as early as possible.
Static and Dynamic Arterial Malperfusion
研究设计
- 研究类型
- Interventional
- 分配方式
- Non Randomized
- 干预模型
- Single Group
- 主要目的
- Diagnostic
- 盲法
- None
入排标准
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Patients diagnosed with an AAD or acute on chronic aortic dissection, with a new diagnosis of malperfusion syndrome (Malperfusion Primary Cohort), by meeting both of the following criteria:
- •Imaging findings indicating reduced flow to the Celiac Trunk, Superior mesenteric artery, either renal artery or either iliac artery
- •Clinical stigmata of end organ ischemia (abdominal pain, distended abdomen, oliguria/anuria, reduced pulses, signs of limb ischemia) correlating with imaging findings
- •o Laboratory findings suggestive of end organ ischemia (lactic acidosis, elevated LFTs, Elevated Creatinine, Rhabdomyolysis, Electrolyte abnormalities) correlating with imaging findings
- •Patients diagnosed with an AAD undergoing surgical repair without evidence of malperfusion syndrome preoperatively, but who develop malperfusion syndrome due to dynamic flow changes after true lumen flow is reinstituted intraoperatively as indicated by new clinical signs or new laboratory results meeting the following criteria (Malperfusion Secondary Cohort):
- •New Clinical signs include: Loss of femoral pulses, distended abdomen, reduced urine output, dusky/cold extremities
- •New Laboratory results include: Rising lactate (>50% above baseline), Rising Creatinine, Metabolic Acidosis, Rising LFTs
- •Patients diagnosed with an AAD undergoing surgical repair without evidence of malperfusion syndrome preoperatively and postoperatively (No Malperfusion Cohort).
排除标准
- •Subject has not been diagnosed with AAD, or acute on chronic aortic dissection
- •Subject is not hemodynamically stable to undergo IVUS evaluation
- •Subject has anatomy or pre-existing condition precluding safe use of IVUS evaluation
- •Subject has a pre-existing condition that may explain evidence of malperfusion (i.e. Dialysis patient with severe renal stenosis).
- •Subject or substitute decision maker has language barrier and no translator available at the time of obtaining informed consent to participate in the study.
研究组 & 干预措施
Malperfusion Primary Cohort
Patients presenting to hospital with AAD meeting criteria for malperfusion syndrome preoperatively which includes both components:
- Imaging findings indicating reduced flow to the Celiac Trunk, Superior mesenteric artery, either renal artery or either iliac artery
- Clinical stigmata of end organ ischemia (abdominal pain, distended abdomen, oliguria/anuria, reduced pulses, signs of limb ischemia) OR Laboratory findings suggestive of end organ ischemia (lactic acidosis, elevated LFTs, Elevated Creatinine, Rhabdomyolysis, Electrolyte abnormalities)
干预措施: Intravascular ultrasound 0.035 PV IVUS catheter (Volcano Therapeutics, Rancho Cordova, CA) (Device)
Malperfusion Secondary Cohort:
Patients who develop new clinical signs or laboratory results indicating distal malperfusion after proximal repair of the AAD is complete and proximal blood flow is redirected into the true lumen.
- New Clinical signs include: Loss of femoral pulses, distended abdomen, reduced urine output, dusky extremities
- New Laboratory signs include: Rising lactate (>50% above baseline), Rising Creatinine, Metabolic Acidosis, Rising LFTs
干预措施: Intravascular ultrasound 0.035 PV IVUS catheter (Volcano Therapeutics, Rancho Cordova, CA) (Device)
No Malperfusion Cohort
Patients presenting with AAD with no evidence of malperfusion syndrome preoperatively and postoperatively.
干预措施: Intravascular ultrasound 0.035 PV IVUS catheter (Volcano Therapeutics, Rancho Cordova, CA) (Device)
结局指标
主要结局
Primary Safety Endpoint
时间窗: 30 days
Composite of all-cause in hospital mortality, acute kidney injury requiring new dialysis, mesenteric ischemia requiring intervention and major vascular complications.
Primary Effectiveness Endpoint
时间窗: 30 days
Composite of all-cause in hospital mortality, acute kidney injury requiring dialysis, mesenteric ischemia requiring surgical resection and major vascular complications.
次要结局
- Secondary Effectiveness Endpoint(30 days)
研究者
Karama Bayamin
Cardiac Surgery Resident
London Health Sciences Centre