Influence of Anesthesia on Mechanical Efficiency of Left Ventricle in Patients Undergoing Open Heart Surgery

The recruitment status of this study is unknown because the information has not been verified recently.
Verified July 2011 by Sheba Medical Center.
Recruitment status was  Recruiting
Sponsor:
Information provided by:
Sheba Medical Center
ClinicalTrials.gov Identifier:
NCT01397331
First received: July 14, 2011
Last updated: July 18, 2011
Last verified: July 2011
  Purpose

The aim of the study is to delineate and compare the changes in coupled mechanical properties of left ventricle and arterial vascular bed caused by two popular anesthetic protocols commonly used in cardiac surgery (intravenous, based on the infusion of propofol, versus inhalational, based on isoflurane) on different stages of the surgery.


Condition Intervention Phase
Heart; Dysfunction Postoperative, Cardiac Surgery
Disorder; Heart, Functional, Postoperative, Cardiac Surgery
Drug: Isoflurane
Drug: Propofol
Phase 4

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Safety/Efficacy Study
Intervention Model: Parallel Assignment
Masking: Double Blind (Subject, Outcomes Assessor)
Primary Purpose: Treatment
Official Title: Influence of Anesthesia on Mechanical Efficiency of Left Ventricle in Patients Undergoing Open Heart Surgery

Resource links provided by NLM:


Further study details as provided by Sheba Medical Center:

Primary Outcome Measures:
  • Changes of the relationship between left ventricular end-systolic elastance and effective arterial end-systolic elastance. [ Time Frame: 15 minutes and 30 minutes after the induction of anesthesia in Inhalational Group and TIVA Group respectively, 15 minutes after the separation from cardiopulmonary bypass, and before the transfer of the patient to the Intensive Care Unit in both groups ] [ Designated as safety issue: No ]

Secondary Outcome Measures:
  • Changes in vascular tone and cardiac afterload [ Time Frame: 15 minutes and 30 minutes after the induction of anesthesia in Inhalational Group and TIVA Group respectively, 15 minutes after the separation from cardiopulmonary bypass, and before the transfer of the patient to the Intensive Care Unit in both groups ] [ Designated as safety issue: No ]
    arterial end-systolic elastance, left ventricular end-systolic stress

  • Changes of measures of global systolic left ventricular function [ Time Frame: 15 minutes and 30 minutes after the induction of anesthesia in Inhalational Group and TIVA Group respectively, 15 minutes after the separation from cardiopulmonary bypass, and before the transfer of the patient to the Intensive Care Unit in both groups ] [ Designated as safety issue: No ]
    left ventricular end-systolic elastance, systolic strain and strain rate, myocardial performance index, ejection fraction


Estimated Enrollment: 30
Study Start Date: July 2010
Estimated Study Completion Date: April 2012
Estimated Primary Completion Date: December 2011 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: Inhalational anesthesia
Group of patients undergoing the surgery under anesthesia based on inhalational anesthetic
Drug: Isoflurane
Anesthesia based on inhalation of 1-1.5 Minimal Alveolar Concentration of Isoflurane with the addition of infusion of remifentanil
Active Comparator: TIVA
Group of patients undergoing the surgery under total intravenous anesthesia
Drug: Propofol
Anesthesia based on the infusion of 2-5 mg/kg/h of propofol with the addition of infusion of remifentanil

Detailed Description:

Background

From mechanical point of view the goal of the cardiovascular system is to distribute the kinetic energy of blood ejection from the left ventricle (LV) to body organs with minimal loss and greatest efficiency. The left ventricle and the arterial circulation work as "coupled" system. The ideal coupling supposes that a maximum of the energy produced by the LV is converted into forward flow to perfuse the body organs. This matching between "the source" (LV) and "the load" (arterial circulation) is governed by the mechanical properties of these parts of cardiovascular system.

Variety of pathological conditions change this coupling in such a way that may adversely affect the organ blood flow in the presence of unchanged or even high cardiac output, or significantly increase the metabolic demand on the LV for the maintenance of adequate systemic perfusion due to decrease of mechanical efficiency of the work produced by LV.

Although effects of anesthetic agents on myocardial contractility and peripheral vascular tone were extensively studied in clinical conditions, little is known about their influence on ventriculo-arterial coupling. Propofol and inhalational agents appear to impair this equilibrium in animal experiments. This is not surprising, since these agents cause complex dose-dependent changes in many physiologic parameters, including myocardial contractility, left ventricular preload and afterload, diastolic properties of myocardium and baroreceptor control of hemodynamics. Although these properties of anesthetic agents have been delineated extensively, very limited data characterizing their influence on ventriculo-arterial coupling in clinical conditions exist. This information is especially meaningful while planning the anesthetic management of patients undergoing cardiac surgery, where maintenance of circulatory homeostasis is of outmost importance. Since the main hemodynamic goal during anesthesia of the patient with cardiovascular disease is to provide optimal tissue perfusion with minimal myocardial oxygen demand, i.e. with maximal mechanical efficiency, knowledge of anesthetic induced changes in ventriculo-arterial coupling is extremely relevant from the clinical point of view.

The most convenient method for the evaluation of ventriculo-arterial coupling is the analysis of the relationship between LV end-systolic elastance, load-independent measure of myocardial contractility, and effective arterial end-systolic elastance, measure mechanical loading conditions8. Physiological data necessary for the calculation of these parameters may be acquired in relatively non-invasive way by combining and analyzing together recording of arterial blood pressure waveform and data of changes of LV volume, which may be obtained by means of echocardiography.

Objectives

General

The aim of the study is to delineate and compare the changes in ventriculo-arterial coupling caused by two popular anesthetic protocols commonly used in cardiac surgery (intravenous, based on the infusion of propofol, versus inhalational, based on isoflurane) on different stages of the surgery.

Specific

  1. To compare influence of two anesthetic protocols on myocardial contractility at the end of the surgery.
  2. To assess net changes in effective arterial elastance produced by surgery with the use of cardiopulmonary bypass and evaluate possible differences between these two anesthetic protocols in respect to changes of arterial tone.
  3. To evaluate the preservation of ventriculo-arterial coupling by two different anesthetic modes.
  Eligibility

Ages Eligible for Study:   18 Years and older
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Criteria

Inclusion Criteria:

  • Patients undergoing elective cardiac surgery

Exclusion Criteria:

  • Emergent surgery.
  • History of previous cardiac surgery.
  • Significant arrhythmias.
  • More than trivial valvular disorder.
  • Absence of written informed consent.
  • Contraindications for transesophageal echocardiography.
  • Pregnant women.
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT01397331

Contacts
Contact: Sergey Preisman, M.D. +972-3-5302754 Sergey.Preisman@sheba.health.gov.il
Contact: Eduard Amlinsky, M.D. +972-3-5302754 eduard.amlinsky@gmail.com

Locations
Israel
Department of Anesthesia and Intensive Care, Sheba Medical Center Recruiting
Tel Hashomer, Ramat Gan, Israel, 52621
Sponsors and Collaborators
Sheba Medical Center
Investigators
Principal Investigator: Sergey Preisman, M.D. Department of Anesthesia and Intensive Care, Sheba Medical Center, Israel 52621
  More Information

No publications provided

Responsible Party: Sergey Preisman, M.D., Department of Anesthesia and Intensive Care, Sheba Medical Center, Tel Hashomer, Israel 52621
ClinicalTrials.gov Identifier: NCT01397331     History of Changes
Other Study ID Numbers: SHEBA-09-7199-SP-CTIL
Study First Received: July 14, 2011
Last Updated: July 18, 2011
Health Authority: Israel: Israeli Health Ministry Pharmaceutical Administration

Keywords provided by Sheba Medical Center:
inhalational anesthesia
intravenous anesthesia
cardiac surgery

Additional relevant MeSH terms:
Anesthetics
Isoflurane
Propofol
Central Nervous System Depressants
Physiological Effects of Drugs
Pharmacologic Actions
Central Nervous System Agents
Therapeutic Uses
Anesthetics, Inhalation
Anesthetics, General
Anesthetics, Intravenous
Hypnotics and Sedatives

ClinicalTrials.gov processed this record on July 29, 2014