Impact of Catecholamine-O-Methyl-Transferase Enzyme Activity on Clinical and Biological Parameters in Patients After Cardiac Surgery.
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 250
- 试验地点
- 1
- 主要终点
- duration of vasoplegia and incidence of acute renal failure following cardiopulmonary bypass
研究概览
简要总结
Although clinical risk factors for postoperative development of vasodilatory shock and acute renal failure have been identified; there is a considerable proportion of patients undergoing cardiac surgery where this syndrome cannot be predicted.
We sought to investigate the impact of Catecholamine-O-Methyltransferase (COMT) polymorphism on the duration of vasodilatory shock and other important clinical outcomes in cardiac surgery patients.
COMT is a key enzyme in the degradation of catechols eg. catecholamines. 25% of the population have a low activity (L/L) of this enzyme. Sustained low COMT activity is associated with an altered metabolic profile of catecholamines and their degradation products.
The process of cardiopulmonary bypass (CPB)over-activates some of the same mechanisms the body uses to defend itself against severe infection. One of the main overactive defence mechanisms is the release of highly toxic compounds derived from oxygen - a process called 'oxidative-stress'. Increased reactive oxygen species (ROS) generation can lead to inactivation of biologic mediators, including catecholamines. It is well established that some radicals autoxidizes catecholamines, including DA, NE, and epinephrine and contribute significantly to vasoplegia.
As part of this study, we will take six 2.7mL samples of blood, collected before, and after the operation, from the arterial catheter routinely inserted in every patient. This blood will be used to measure COMT genotype, the concentration of plasma-catecholamines as well as marker of oxidative stress.
Our plan is to enrol patients undergoing cardiac surgery if the use of the CPB is planned.
详细描述
Aim of the study
To explore if there is an impact of LL COMT genotype on clinical and biological outcome variables in patients undergoing cardiac surgery compared to HH genotype.
Background
Cardiac surgery has been shown to be an effective method for prolonging life in patients with severe coronary artery disease or valvular disease or a combination thereof.
Catechol-O-Methyl-Transferase (COMT) catalyses the O-methylation of biologically active catechols and is responsible for the degradation of catecholamines and catecholestradiols.
研究设计
- 研究类型
- Observational
- 时间视角
- Prospective
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Patients undergoing elective cardiac surgery (in whom CPB is planned) at the Austin Hospital and Warringal Private Hospital.
排除标准
- •Intake of Levodopa
- •Intake of COMT inhibitors (e.g. Entacapone, Tolcapone)
- •Intake of monoamino oxidase inhibitors type A and B (e.g. Moclobemide, Selegiline, Rasagiline)
- •Patients below 18 years of age
- •oral steroids
- •emergency patients (cardiac symptoms occurred < 24 hours prior to operation)
- •patients receiving IV nitrates/nitroprusside sodium
结局指标
主要结局
duration of vasoplegia and incidence of acute renal failure following cardiopulmonary bypass
次要结局
- length of stay in intensive care and in hospital, requirement of renal replacement therapy, mortality