SSVC-CI During CABG (SVC-CI)

Utility of the Superior Vena Cava Collapsibility Index (SVC-CI) to Predict Fluid Responsiveness in Patients With Coronary Artery Disease Undergoing Surgical Revascularization

To investigate the superior vena cava collapsibility index (SVC-CI), measured via transesophageal echocardiography (TEE), as a marker of fluid responsiveness. Two groups will be compared in this study. Groups will be identified by obtaining cardiac output (CO) by standard means using the TEE or pulmonary arterial catheter (PAC). Both of these monitors are considered standard for patient's undergoing coronary artery bypass grafting surgery (CABG) and recording initial CO readings. Based on CO, the patient's will be placed in study groups one or two. Participants with normal and mildly reduced left ventricular ejection fraction (LVEF >40%) for group one and those with moderately to severely reduced LVEF (<40%) in the second group.

Following group separation, we will measure the SVC-CI and CO metric in both groups. The intervention will be an operating room table tilt test (head up and then head down) to artificially simulate giving the patient additional fluid. Before and after table tilt, the SVC-CI and CO will be obtained and measured. The SVC-CI is a mathematical equation determined by distance measurements taken via TEE to identify how much the superior vena cava has collapsed following table tilt. Participants will be considered responders if the CO increases by 12% following intervention. Non responders less than 12% change in CO following intervention. Our hypothesis is that the SVC-CI can differentiate responders vs non-responders with regards to fluid responsiveness with adequate sensitivity and specificity in participants with CAD undergoing isolated CABG. The SVC-CI numerical values for the two groups, responders and non-responders, will calculate a threshold of sensitivity and specificity percentages for future patients undergoing CABG.

Study Overview

• Status: Recruiting
• Conditions: Coronary Artery Bypass Grafting Surgery (CABG)
• Intervention / Treatment: Other: a change in operating room table position, which will mimic an IV fluid bolus

• Study Type: Observational
• Enrollment (Estimated): 120

Contacts and Locations

• Study Contact: Name: Cynthia Reed, BS; Phone Number: 282465 717-531-0003; Email: creed@pennstatehealth.psu.edu
• Study Contact Backup: Name: Edward Stredny, MD; Phone Number: 717-531-8521; Email: estredny@pennstatehealth.psu.edu

Study Locations

• United States
  • Pennsylvania
    • Hershey, Pennsylvania, United States, 17033
      • Recruiting
      • Penn State Hershey Medical Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Participants with CAD undergoing CABG utilizing cardiopulmonary bypass

Description

Inclusion Criteria:

1. Age ≥ 18
2. Participants with CAD undergoing CABG utilizing cardiopulmonary bypass
3. Participants who are able to consent for themselves
4. Primary language is English

Exclusion Criteria:

1. Age less than 18 years of age
2. Participants with CAD undergoing off-pump coronary artery bypass (OP-CAB)
3. Severe cardiac valvular pathologies or active congestive heart failure
4. Participants in active arrhythmia such as atrial fibrillation and atrial flutter at the time of data collection.
5. Participants who are unable to consent for themselves
6. Primary language is something other than English

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Group 1; (LVEF>40%)	Other: a change in operating room table position, which will mimic an IV fluid bolus; Cardiac Output (CO) measurements will be obtained at two separate time points: prior to sternotomy (opening of the chest) and after separation from cardiopulmonary bypass. Intervention; the participant will be placed in the reverse Trendelenburg position (head up) to 15 degrees for 60-90 seconds. CO measurement will be obtained; the participant will be transitioned to the Trendelenburg position (head down) to 15 degrees for 60-90 seconds. CO measurement will be obtained
Group 2; (LVEF<40%),	Other: a change in operating room table position, which will mimic an IV fluid bolus; Cardiac Output (CO) measurements will be obtained at two separate time points: prior to sternotomy (opening of the chest) and after separation from cardiopulmonary bypass. Intervention; the participant will be placed in the reverse Trendelenburg position (head up) to 15 degrees for 60-90 seconds. CO measurement will be obtained; the participant will be transitioned to the Trendelenburg position (head down) to 15 degrees for 60-90 seconds. CO measurement will be obtained

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
To determine an appropriate cut-off value for the SVC-CI in participants with CAD undergoing isolated CABG to distinguish volume responders from non-responders.	Responders increases by 12% or more following intervention; Non responders less than 12% change in CO following intervention.	10 minutes of time added to your surgery time.

Collaborators and Investigators

• Sponsor: Milton S. Hershey Medical Center
• Investigators: Principal Investigator: Edward Stredny, MD, Milton S. Hershey Medical Center

Publications and helpful links

General Publications

• 1. Charbonneau H, Riu B, Faron M, et al. Predicting preload responsiveness using simultaneous recordings of inferior and superior vena cavae diameters. Crit Care. 2014;18(5):473. 2. Hrishi AP, Sethuraman M, Menon G. Quest for the holy grail: Assessment of echo-derived dynamic parameters as predictors of fluid responsiveness in patients with acute aneurysmal subarachnoid hemorrhage. Ann Card Anaesth. 2018;21(3):243-248. 3. Vieillard-Baron A, Chergui K, Rabiller A, et al. Superior vena caval collapsibility as a gauge of volume status in ventilated septic patients. Intensive Care Med. 2004;30(9):1734-1739. 4. Vignon P, Repessé X, Bégot E, et al. Comparison of Echocardiographic Indices Used to Predict Fluid Responsiveness in Ventilated Patients. Am J Respir Crit Care Med. 2017;195(8):1022-1032.

Study record dates

Study Major Dates

• Study Start (Actual): February 24, 2025
• Primary Completion (Estimated): January 1, 2028
• Study Completion (Estimated): January 1, 2029

Study Registration Dates

• First Submitted: October 15, 2024
• First Submitted That Met QC Criteria: October 15, 2024
• First Posted (Actual): October 16, 2024

Study Record Updates

• Last Update Posted (Actual): May 7, 2026
• Last Update Submitted That Met QC Criteria: May 1, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Vascular Diseases; Cardiovascular Diseases; Heart Diseases; Arteriosclerosis; Arterial Occlusive Diseases; Coronary Artery Disease; Myocardial Ischemia; Coronary Disease
• Other Study ID Numbers: Study 24328 (Other Identifier: Penn State Health Penn State Hershey Medical Center)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED
• IPD Plan Description: It will depend if the data is shared in data bases and what kind of data bases. this has not been determined.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No