Clinical Trial Details
— Status: Recruiting
Administrative data
| NCT number |
NCT03543345 |
| Other study ID # |
HAZ190 |
| Secondary ID |
|
| Status |
Recruiting |
| Phase |
|
| First received |
|
| Last updated |
|
| Start date |
June 1, 2018 |
| Est. completion date |
August 28, 2018 |
Study information
| Verified date |
June 2018 |
| Source |
Assiut University |
| Contact |
Hazim A. Kaml, MBcCH |
| Phone |
+201118186565 |
| Email |
ihazim1990[@]gmail.com |
| Is FDA regulated |
No |
| Health authority |
|
| Study type |
Observational
|
Clinical Trial Summary
Proximal RCA occlusions were very often found among men with fatal pre-hospital MI; whereas
left-sided coronary occlusions were significantly more frequent in hospital-admitted
survivors of MI. Left-sided coronary occlusions may be associated with a more favorable
pre-hospital phase of acute MI compared to proximal RCA occlusions. Proximal RCA occlusion
increases the risk of arrhythmia and shock leading to increase the mortality. Sinus
bradycardia and cardiogenic shock accounts for the majorities of the mortalities of RCA
occlusion
Description:
Myocardial infarction is a common presentation of coronary artery disease. The World Health
Organization estimated in 2004, that 12.2% of worldwide deaths were from ischemic heart
disease; with it being the leading cause of death in high- or middle-income countries and
second only to lower respiratory infections in lower-income countries. Worldwide, more than 3
million people have STEMIs and 4 million have NSTEMIs a year . STEMIs occur about twice as
often in men as women .
Myocardial infarction means that the tissue ischemia caused tissue death, as a result of
diminished blood supply to a part of the heart muscles. The blood supply of the heart is
coronary arteries (right and left). Proximal RCA occlusions were very often found among men
with fatal pre-hospital MI; whereas left-sided coronary occlusions were significantly more
frequent in hospital-admitted survivors of MI. Left-sided coronary occlusions may be
associated with a more favorable pre-hospital phase of acute MI compared to proximal RCA
occlusions .
The right coronary artery (RCA) supplies the right ventricle, 25% to 35% of the left
ventricle and SA node in 60% of people. Proximal RCA occlusion increases the risk of
arrhythmia and shock leading to increase the mortality. Sinus bradycardia and cardiogenic
shock accounts for the majorities of the mortalities of RCA occlusion.
Sinus bradycardia is more frequent when the infarct-related artery is the RCA than other
arteries involvement. Proximal occlusions of the RCA presented sinus bradycardia more than
medial and distal occlusions.
Mortality of cardiogenic shock due to right ventricular infarction (55%) was comparable to
that due to left ventricular infarction (59%) in spite of patients being younger and a
greater incidence of single vessel disease. The worse prognosis in patients with RV
myocardial involvement may be related to the increased risk of life-threatening ventricular
arrhythmias in these patients.
Approximately one half of patients who present with signs and symptoms of acute inferior
myocardial infarction have proximal occlusion of the dominant right coronary artery (RCA) and
also show ECG signs of RV wall ischemia or infarction. Occlusion sufficiently proximal to
cause RV free wall injury also frequently compromises the blood supply to the sinoatrial
node, atrium and atrioventricular (AV) node, producing such effects as sinus bradycardia,
atrial infarction, atrial fibrillation and AV block.
The transthoracic echocardiography is the most common method to assess the function of the
right ventricular function as it non-invasive, inexpensive and available in most of the
hospitals. The presence of RV dysfunction on early echocardiography is an important predictor
of an adverse prognosis, both short-and long-term, in STEMI patients.
The Tissue Doppler Imaging method depicts myocardial motion (measured as tissue velocity) at
specific locations in the heart. Tissue velocity indicates the rate at which a particular
point in the myocardium moves toward or away from the transducer. Integration of velocity
over time yields displacement or the absolute distance moved by that point.
Evaluation of right ventricular function by echocardiography is challenging and often ignored
in clinical practice. Tricuspid annular velocity correlates with right ventricular ejection
fraction . Tricuspid annular excursion (tricuspid displacement) predicted 2-year survival in
patients with pulmonary hypertension . Isovolumic acceleration, derived from tissue velocity,
is a load-independent measure of contractility and correlates with right ventricular
end-systolic elastance. This correlation is less pronounced in clinical studies . More recent
experimental data suggest a weak relationship between isovolumic acceleration and regional
contractility. Systolic velocity and strain best correlated with invasively determined right
ventricular stroke volume and dynamically tracked changes in right ventricular function
during vasodilator infusion. Strain rates and strain quantitate regional right ventricular
systolic function in various pathologies
