Augmented Pacing for Shock in the Cardiac Intensive Care Unit

Augmented Pacing for Shock in the Cardiac Intensive Care Unit - A Pilot Patient-level Crossover Trial

The goal of this clinical trial is to learn if backup pacing at an increased rate improves hemodynamics in adults with relative bradycardia, a permanent pacemaker, and cardiogenic shock. The main question it aims to answer is:

Does increasing the backup pacing rate to 100 beats per minute lead to improved cardiac index compared to a backup pacing rate of 75 beats per minute

Participants who are already hospitalized in the Cardiovascular Intensive Care Unit with a permanent pacemaker and pulmonary artery catheter in place will be enrolled in this study. Participants will be exposed to each pacemaker rate in a randomized order with hemodynamics assessed after 10 minutes at each rate.

Study Overview

• Status: Active, not recruiting
• Conditions: Shock; Bradycardia; Cardiogenic Shock
• Intervention / Treatment: Device: Backup Pacing Rate Change

• Study Type: Interventional
• Enrollment (Estimated): 25
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Tennessee
    • Nashville, Tennessee, United States, 37232
      • Vanderbilt University Medical Center

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Adults (age 18 and older)
• Located in the CVICU
• FDA approved permanent pacemaker in place (inclusive of dual-chamber and Bi-Ventricular ICDs) with labeling that allows backup pacing setting at 100 bpm.
• Receiving a vasopressor or Inotrope for at least 4 hours
• Average HR ≤ 75 bpm over the last hour (on Telemetry review)
• Pulmonary artery catheter in place with functioning thermistor and pulmonary artery port.

Exclusion Criteria:

• Single chamber Implantable Cardiac Defibrillator
• Sinus rhythm with a leadless pacemaker
• Ventricular Tachycardia or Ventricular Fibrillation arrest in last 48 hours
• Hemodynamic instability within the last 4 hours, defined as an increase in the dose of norepinephrine > 10 mcg/min, an increase of epinephrine > 10 mcg/kg/min, or initiation of a second vasopressor
• Alternative indication for pacing rate change (i.e Torsade de Pointes, Recurrent Ventricular Tachycardia)
• Comfort-focused care or anticipated death within 24 hours
• Mechanical circulatory support in place
• Newly discovered pacing system malfunction (lead displacement, loss of capture, elevated capture threshold, significant lead impedance change, battery depletion, undersensing or oversensing)
• Non-English Speaking

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Other: Standard Pacing (75 bpm) then Augmented Pacing (100 bpm); Backup pacing rate will be set to 75 bpm first then 100 bpm second	Device: Backup Pacing Rate Change; Patients will have backup pacing programmed to A (75 bpm) and B (100 bpm), randomizing to sequence of exposure A-B or B-A
Other: Augmented Pacing Rate (100 bpm) then Standard Pacing (75 bpm); Backup pacing rate will be set to 100 bpm first then 75 bpm second	Device: Backup Pacing Rate Change; Patients will have backup pacing programmed to A (75 bpm) and B (100 bpm), randomizing to sequence of exposure A-B or B-A

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Cardiac Index by thermodilution	Cardiac Index measured by thermodilution (in liters per minute per meters squared)	At baseline and 10 minutes after each rate programmed (i.e at 0, 15, and 30 minutes)

Secondary Outcome Measures

Outcome Measure	Time Frame
Cardiac Index by Indirect Fick	0, 15, 30 minutes.
Cardiac Output by thermodilution	0, 15, 30 minutes.
Cardiac Output by indirect fick	0 ,15, 30 minutes
Central Venous Pressure	0, 15, 30 minutes
Pulmonary Artery Systolic Pressure	0, 15, 30 minutes
Pulmonary Artery Diastolic Pressure	0, 15, 30 minutes
Pulmonary Artery Pulsitility Index	0, 15, 30 minutes
Right Ventricular Stroke Work Index	0, 15, 30 minutes
Pulmonary Artery (Mixed Venous) Blood Hemoglobin saturation	0, 15, 30 minutes
Cardiac Power Index (Thermodilution and indirect fick)	0, 15, 30 minutes
Cardiac Power Output (Thermodilution and indirect fick)	0, 15, 30 minutes
Systolic Blood pressure	0, 15, 30 minutes
Diastolic Blood Pressure	0, 15, 30 minutes
Mean Arterial Pressure	0, 15, 30 minutes
Difference in vasopressor/inotrope requirements	0, 15, 30 minutes
Arrhythmia events (Atrial and Ventricular)	0, 15, 30 minutes
Percentage of PVCs	0, 15, 30 minutes
Pacing percentage (Atrial, RV or Bi-V)	0, 15, 30 minutes

Collaborators and Investigators

• Sponsor: Vanderbilt University Medical Center

Study record dates

Study Major Dates

• Study Start (Actual): April 22, 2025
• Primary Completion (Estimated): April 22, 2027
• Study Completion (Estimated): April 22, 2027

Study Registration Dates

• First Submitted: November 1, 2024
• First Submitted That Met QC Criteria: November 27, 2024
• First Posted (Actual): December 3, 2024

Study Record Updates

• Last Update Posted (Actual): May 6, 2026
• Last Update Submitted That Met QC Criteria: May 4, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: Shock; Cardiogenic Shock; Pacing; Bradycardia
• Additional Relevant MeSH Terms: Vascular Diseases; Cardiovascular Diseases; Pathologic Processes; Heart Diseases; Arrhythmias, Cardiac; Infarction; Necrosis; Myocardial Ischemia; Myocardial Infarction; Ischemia; Pathological Conditions, Signs and Symptoms; Shock, Cardiogenic; Shock; Bradycardia
• Other Study ID Numbers: 241410

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

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