MedPath

Nitrite Mediated Cardioprotection During Coronary Artery Bypass Surgery

Phase 2
Conditions
Coronary Artery Bypass Surgery
Interventions
Registration Number
NCT01098409
Lead Sponsor
University Hospital Birmingham NHS Foundation Trust
Brief Summary

The purpose of this study is to determine whether sodium nitrite administration 24 hours prior to or during coronary artery bypass surgery protects the heart better from lack of blood flow which occurs as part of this type of operation. The study will also determine what the mechanisms of this cardioprotection are.

Detailed Description

In recent years, there has been much interest in sodium nitrite as a cytoprotective agent in in vitro and animal models. A recent study undertaken in a canine model of myocardial infarction demonstrated a 50% reduction in myocardial injury following the administration of sodium nitrite prior to the ischemic event. In humans, the setting of coronary artery bypass surgery lends itself well to study potential cytoprotective agents. During cardiac surgery, the heart undergoes a period of ischemia allowing the surgeons to operate on the heart. This is followed by a period of reperfusion which in itself can add to cellular injury. Such injury can hinder post-operative myocardial recovery.

The aim of this pilot study is to determine whether the cardioprotective effects of sodium nitrite demonstrated in animal models are translated in humans and to determine the exact underlying mechanisms of this cytoprotection. Patients undergoing coronary artery bypass grafting surgery who give written, informed consent will receive sodium nitrite 24 hours prior to surgery, during cardiac surgery or placebo. Myocardial injury will be assessed through the measurement of biochemical markers such as troponin T. Cardiac biopsy samples will be obtained to determine underlying molecular mechanisms of this cardioprotection. The other aim of this pilot study is to determine what dose of sodium nitrite (i.e. 0.2mcg/kg/min or 1mcg/kg/min) is optimal for cardioprotection. This study will form pilot data also for a larger clinical trial with clinical endpoints.

Recruitment & Eligibility

Status
UNKNOWN
Sex
All
Target Recruitment
50
Inclusion Criteria
  • Patients undergoing elective first time multi-vessel coronary artery bypass surgery
  • Older than 18 years of age
Exclusion Criteria
  • Significant psychiatric /neurological impairment that might prevent adherence to the requirements of the protocol or the ability to give informed consent
  • Inability to read the Information Sheet.
  • Redo operation
  • Age >80 years
  • Pregnancy
  • Renal Impairment requiring pre-operative renal support
  • Diabetes Mellitus
  • Intended heart valve or additional surgery
  • Episodes of angina or ischemia within 48hours prior to the procedure

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
sodium nitrite during surgerysodium nitrite-
sodium nitrite 24 hours beforesodium nitrite-
0.9% sodium chloride0.9% sodium chloride-
Primary Outcome Measures
NameTimeMethod
Troponin T72 hours post release of aortic cross clamp

Biochemical marker of myocardial injury

Secondary Outcome Measures
NameTimeMethod
Troponin T48 hours post release of aortic cross clamp
troponin T12 hours post release of aortic cross clamp
Creatinine Kinase myocardial Fraction (CKMB)72 hours post release of aortic cross clamp
venous methemoglobinaemiaimmediately before infusion of study drug

study drug means both sodium nitrite and placebo

plasma 8-isoprostanebefore aortic cross clamp administration
Nitric oxide metabolites in cardiac tissue10minutes after release of aortic cross clamp
Cardiac output studiesupto 12 hours after release of aortic cross clamp
inotrope usageup to 12 hours after release of aortic cross clamp
venous methemoglobinemiaimmediately after infusion of study drug.

Study drug could be sodium nitrite or placebo and each infusion last 30minutes.

Plasma 8 isoprostane levels5minutes after discontinuation of cardiopulmonary bypass

Trial Locations

Locations (1)

University Hospitals Birmingham NHS Trust

🇬🇧

Birmingham, United Kingdom

© Copyright 2025. All Rights Reserved by MedPath