الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 140 |  |  |
| | | from | 140 | | |
Abstract
The term ischemic cardiomyopathy has been used to
describe significantly impaired left ventricular function
(left ventricular ejection fraction ≤35 to 40 percent) that
results from coronary artery disease. Ischemic
cardiomyopathy can result from irreversible loss of
myocardium due to prior myocardial infarction or from
reversible loss of contractility due to chronically ischemic
but still viable myocardium.
Revascularization remains an important treatment
option for patients with ongoing anginal symptoms despite
optimal medical therapy.
So, here comes the importance of differentiating
dilated cardiomyopathy due to chronically ischemic viable
myocardium causing increased left ventricular dimensions,
with subsequent heart failure, from dilated cardiomyopathy
due to other non-ischemic causes.
To verify this, current study included 100 patients,
aged above 40 years, with known cardiomyopathy, with left
ventricular ejection fraction less than 40 %, excluding those
of hypertrophic or restrictive types, or marked limitation of
physical activity.
90
All patients included in the study were subjected to the
following:
1. Careful medical history analysis.
2. Physical examination.
3. Twelve-leads surface ECG for any signs of ischemia.
4. Echocardiographic Study, measuring left ventricular
dimensions and volumes in both systole and diastole.
The degree of mitral valve regurgitation was assessed,
and the Wall Motion Score Index was calculated, along
with left ventricular ejection fraction.
5. Nuclear imaging of the heart was performed using
Technetium 99m to assess myocardial viability. Left
ventricular ejection fraction, and volumes were
measured.
6. Left sided cardiac catheterization with coronary
angiography assessed the coronary blood flow, to pick
up ischemic cases.
7. Statistical analysis
The patients were divided according to the coronary
angiographic findings into two groups:
Group A: Dilated Cardiomyopathy
Group B: Ischemic Cardiomyopathy
91
Statistical analysis of the collected data showed the
following:
• Medical history could not differentiate the two groups of
patients.
• ECG could identify 100% of patients of Group B by
utilizing ischemic patterns. Otherwise, the ECG was of
no value. ECG as a diagnostic tool showed a sensitivity
of 100% and specificity of 47%.
• Although Global hypokinesia was found in all subjects
of Group A, none of the data collected by
echocardiography could successfully differentiate the
two groups with reliable accuracy. A specificity of
100% and a sensitivity of 82% were exhibited by
echocardiography as a tool.
• Nuclear testing for myocardial viability is a very good
diagnostic tool in differentiating the two groups of the
study, with a very high sensitivity (100%) and
specificity (97%) values.
In Conclusion
Current study proved that when comparing the
assessment of myocardial viability using nuclear imaging,
to segmental wall motion abnormality, nuclear imaging
carries better predictive values, as per the gold standard
modality (coronary angiography).
92
It was obvious also that during the assessment,
individual tools were not sufficient in differentiating dilated
from ischemic cardiomyopathy. Where, combing history
with ECG and more advanced tools, as echocardiography
and nuclear imaging, had a very good diagnostic capability.