This is a free website for Nuclear Medicine Technologists and Students who wish to broaden their understanding of Nuclear Cardiology Practices and Principles.

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Syllabus
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1a: History
1b: Guidelines
1c: Epidemiology
1d: Structure
1e: Circulation
Lesson 1 REVIEW

2a: Anomalies
2b: Dextrocardia
2c: Coronary Arteries
2d: Indicators of Function
Lesson 2 REVIEW

3a: Electrophysiology
3b: Conduction
3c: Action Potential
3d: Autonomic System
Lesson 3 REVIEW

4a: Electrocardiography
4b: EKG Slideshow
4c: EKG Interpretation
4d: Myocardial Damage
Lesson 4 REVIEW

5a: Cardiovascular Disease
5b: Coronary Syndromes
5c: Atherosclerosis
5d: Myocardial Infarction
5e: Cardiac Stress Testing
5f: Cardiac Medications
5g: Revascularization
Lesson 5 REVIEW

6a: Diagnostic Imaging
6b: Radiopharmaceuticals
6c: Thallium Scintigraphy
6d: Tc99m MPI Agents
6e: PET Imaging
6f: Blood Pool Imaging
6g: Cardiac Function
Lesson 6 REVIEW

7a: Planar Cardiac Imaging
7b: Cardiac SPECT Imaging
7c: Cardiac SPECT Anatomy
7d: Interpretation
7e: Attenuation Correction

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Ejection Fraction

Probably the most widely accepted measure of LV function is the ejection fraction (EF). This volume represents the percentage of blood in the ventricle that is ejected per beat. A reduced EF indicates a lower survival rate in medically treated patients with CAD, valvular heart disease and primary cardiomyopathy, and patients undergoing CABG, aneurysm or valve replacement.

Ejection fraction (%) = [ED (net) – ES (net)] ÷ ED x 100

Counts detected in the LV are proportional to volume, and the change from end-systolic counts (ESC) to end-diastolic counts (EDC) of the LV can be used for the calculation of left ventricular ejection fraction.

The normal range for the left ventricle is 50-75%, the right side is about 45%.

Cardiac Output

Cardiac output (CO) is the volume of blood pumped out to the body by the LV. It is a measurement of unit of blood per unit of time, usually expressed in liters per minute. Because body mass can cause this value to vary significantly, clinicians sometimes use the Cardiac Index (CI) to measure function. The cardiac index is defined as the cardiac output divided by the body surface area measured in square meters.

In the normal adult male, the average CO is 5.6 liters/minute and the average body surface area is 1.7 square meters; thus the average CI is about 3 liters/min per square meter. In normal resting subjects, 25 percent of the total cardiac output goes to the splanchnic bed (liver and gut) and 20 per cent goes to the renal circulation; the brain receives 12%, while the coronary flow accounts for about 4%. During exercise, vasodilation in muscle beds permits flow to the involved muscles to increase from about 20% to 50%, while flow to the splanchnic and renal bed drops proportionally.

Exercise Response

There is a significant difference in ventricular volume responses to the exercise of patients with and without CAD. In normal patients, the increased stroke volume and cardiac output that accompany exercise are met by a reduction in the end-systolic volume without much change in end-diastolic volume. As a result, EF increases.

Exercise induced ischemia increases End Diastolic and End Systolic Volumes, maintaining the stroke volume. STROKE VOLUME is the difference between the end diastolic volume (EDV) and end systolic volume (ESV). By exercise radionuclide techniques, patients with CAD fail to increase EF by at least 5% and/or the presence of one or more exercise-induced wall motion abnormalities. Patients with an ischemic response will demonstrate either no change or a decrease in EF value due to impaired contractility.