The Effects of Trans Venous Cardiac Pacing on Coronary Microvascular Function and Hemodynamics

Study Overview
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Brief Summary
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The study will examine role of transvenous pacing on coronary microcirculation.

Detailed Description
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To study the role of transvenous pacing on the coronary microcirculation. This will be accomplished by gathering data from invasive Fractional Flow Reserve (FFR) and Coronary Flow Reserve (CFR) with and without ventricular pacing.

Official Title
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The Effects of Trans Venous Cardiac Pacing on Coronary Microvascular Function and Hemodynamics

Conditions
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Coronary Microvascular Disease, Cardiac Pacemaker Syndrome

Intervention / Treatment
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* Diagnostic Test: Coronary flow and pressure measurement in patients with ventricular pacing


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: All patients 19 years of age or older with clinical evidence of coronary ischemia undergoing coronary angiogram, and who have a pacemaker. Exclusion Criteria: Acute ST segment myocardial infarction Known sensitivity or contraindication to the agents planned for administration during coronary angiography Pacemaker dependent patients Pregnancy Hypotension (a systolic blood pressure lower than 90mmHg) that would preclude the administration of adenosine Severe renal dysfunction, defined as a estimated glomerular filtration (eGFR) less than 30ml/min, confirmed by recent testing Study subject has any underlying disorder that, in the opinion of the investigator, precludes them from giving informed consent at the time of enrollment

Ages Eligible for Study
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Minimum Age: 19 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Non-Randomized
Intervention Model: Sequential Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Right ventricular Pacemaker<br>Patients with right ventricular pacing and evidence of coronary ischemia who have evidence of coronary ischemia who are to undergo coronary angiogram.When an intermediate stenosis (40-80%) has been identified angiographically, this lesion will undergo further hemodynamic assessment, All data including resting flow, FFR, CFR, vital signs, arrhythmias and patient symptoms will be recorded twice: once when the pacemaker is programmed to pace, and once when the PPM is reprogrammed such that the pacemaker is no longer pacing. | Diagnostic Test: Coronary flow and pressure measurement in patients with ventricular pacing<br>* Coronary flow and pressure measurement in patients with ventricular pacing<br>|
| Other: Biventricular Pacemaker<br>Patients with Biventricular pacing and evidence of coronary ischemia who have evidence of coronary ischemia who are to undergo coronary angiogram.When an intermediate stenosis (40-80%) has been identified angiographically, this lesion will undergo further hemodynamic assessment, All data including resting flow, FFR, CFR, vital signs, arrhythmias and patient symptoms will be recorded twice: once when the pacemaker is programmed to pace, and once when the PPM is reprogrammed such that the pacemaker is no longer pacing. | Diagnostic Test: Coronary flow and pressure measurement in patients with ventricular pacing<br>* Coronary flow and pressure measurement in patients with ventricular pacing<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Patients that exhibit coronary microvascular resistance and dysfunction as reflected by FFR | Microvascular dysfunction with pacing | Up to 12 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Patients that exhibit coronary microvascular resistance and dysfunction as reflected by CFR | Microvascular dysfunction with pacing | Up to 12 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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coronary microvascular dysfunction