Endothelial and Microvascular Functions in Patients With Myocardial Ischemia

Completed

• Conditions: Microcirculation; Biomarkers; Myocardial Ischemia

• Registration Number: NCT03243968
• Lead Sponsor: Rio de Janeiro State University

Brief Summary

Cardiovascular diseases (CVD) are responsible, throughout the world, for high mortality rates and cardiovascular morbidity. Endothelial dysfunction is the earliest marker of clinical atherosclerosis development. Human studies show that endothelial and microvascular dysfunction are independent predictors of ischemic cardiovascular events and long-term prognosis. The study´s objective is to evaluate the endothelial and peripheral microcirculation changes by venous occlusion plethysmography (VOP), nailfoldvideocapillaroscopy (NVC) and serum biomarkers in patients with myocardial ischemia detected by scintigraphy and normal coronarography.

Detailed Description

A cross-sectional study was carried out with 50 participants: 25 with myocardial ischemia detected by scintigraphy and normal coronarography (Ischemic Patient - IP) and 25 healthy non-ischemic individuals (Control Group - CG). All of them were submitted to anamnesis, serum markers (Intercellular Cell Adhesion Molecule \[ICAM\], Vascular Cell Adhesion Molecule\[VCAM\], adiponectin, endothelin, LDL-oxidized and CRP-US), NVC and VOP. Exclusion criteria were: inflammatory diseases, cancer patients, recent traumas, Diabetes Mellitus, obese individuals with BMI\> 35 kg/m², uncontrolled hypertensive patients, and those with active infectious processes. In the NVC,capillary diameters were observed, as well as red blood cells velocity in the capillaries (RBCV, mm/s), maximum red blood cells after 1 minute ischemia (RBCVmax, mm/s) and time to reach maximal velocity (TRBCVmax) and, regarding VOP,the baseline blood flow (ml/min), post 5 minute ischemia flow and vascular resistance (mmHg/ml/min) were evaluated. Data were analyzed using Student's t-tests for independent or Mann-Whitney samples; χ2 or Fisher exact. The absolute and relative variations (delta) of plethysmography measurements versus baseline in each group were analyzed by the Wilcoxon signed-ranks test and compared between the groups by the Mann-Whitney test. For correction of confounding factors, age and BMI, it was used Covariance Analysis (ANCOVA).

Study Timeline

• Study Start: 2014-03-01
• Primary Completion: 2015-08-30
• Study Completion: 2015-08-30
• Status Verified: 2017-08
• Study First Submitted: 2017-08-02
• Study First Submitted QC: 2017-08-04
• Last Update Submitted: 2017-08-04
• Study First Posted: 2017-08-09
• Last Update Posted: 2017-08-09

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 50

Inclusion Criteria

The study population consisted of 50 patients of both sexes, stratified into two groups: patients with myocardial ischemia detected by scintigraphy (group IP, n = 25) and healthy individuals (CG group, n = 25). In the patients who underwent scintigraphy with tomographic sections and presented any type of image attenuation during the examination, they also underwent a complementary prone position technique. Patients without these characteristics scintigraphy methodologies were excluded from the study.

Exclusion Criteria

Exclusion criteria were adopted: patients with type 1 or 2 Diabetes Mellitus, heart failure, myocardial infarction or brain stroke with less than three months of the event, chronic renal disease, users of hormonal or non-hormonal anti-inflammatory drugs, recent trauma (less than three months) autoimmune diseases, active infectious processes, presence of neoplasia, use of Aspirin (anti-inflammatory dose), obesity with BMI>35 kg/m², uncontrolled hypertensive patients, resistant hypertensives, and non-compliance in the examinations or with the signature of the Consent Form.

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
%Hyper	One year	Increment of forearm blood flow during reactive hyperemia after 5 minutes arm ischemia with venous occlusion plethysmography.

Secondary Outcome Measures

Name	Time	Method
Intercellular adhesion molecule (ICAM)	One year	Inflammatory biomarker obtained through withdrawal of venous blood.
Vascular adhesion molecule (VCAM)	One year	Inflammatory biomarker obtained through withdrawal of venous blood.
Adiponectin	One year	Adipokyne obtained through withdrawal of venous blood.
Endothelin	One year	Potent vasoconstrictor obtained through withdrawal of venous blood.
FCD	One year	Functional capillary density. Number of capillaries with flowing red blood cell in microscope area. Obtained from Nailfold videocapillaroscopy.
CRP	One year	C reactive protein obtained through withdrawal of venous blood.
% Nitro	One year	Increment of forearm blood flow after 5 minutes of 400 μg sublingual nitroglycerin application with venous occlusion plethysmography..
AFCD	One year	Afferent capillar diameter. Obtained from Nailfold videocapillaroscopy.
RBCVmax	One year	Maximum red blood cell velocity during reactive hyperemia in fourth finger after one minute ischemia. Obtained from Nailfold videocapillaroscopy.
TRBCVmax	One year	Time to reach Maximum red blood cell velocity during reactive hyperemia in fourth finger after one minute ischemia. Obtained from Nailfold videocapillaroscopy.
LDL-oxidized	One year	Low density lipoprotein oxidized used to measure oxidative stress. It is obtained from venous blood.
EFCD	One year	Efferent capillar diameter. Obtained from Nailfold videocapillaroscopy.
RBCV	One year	Basal red blood cell velocity. Obtained from Nailfold videocapillaroscopy.
%ResHyper	One year	Increment of vascular resistance during reactive hyperemia after 5 minutes arm ischemia with venous occlusion plethysmography.
%ResNitro	One year	Increment of vascular resistance after 5 minutes of 400 μg sublingual nitroglycerin application with venous occlusion plethysmography.
ACD	One year	Apical capillar diameter. Obtained from Nailfold videocapillaroscopy.