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The EF of the right heart, or right ventricular ejection fraction (RVEF), is a measure of the efficiency of pumping into the pulmonary circulation. A heart which cannot pump sufficient blood to meet the body's requirements (i.e., heart failure) will often, but not invariably, have a reduced ventricular ejection fraction. [6]
Electrical waves track a systole (a contraction) of the heart. The end-point of the P wave depolarization is the start-point of the atrial stage of systole. The ventricular stage of systole begins at the R peak of the QRS wave complex; the T wave indicates the end of ventricular contraction, after which ventricular relaxation (ventricular diastole) begins.
Ventricular systole is the contractions, following electrical stimulations, of the ventricular syncytium of cardiac muscle cells in the left and right ventricles. Contractions in the right ventricle provide pulmonary circulation by pulsing oxygen-depleted blood through the pulmonary valve then through the pulmonary arteries to the lungs.
Stroke volume will normally be in the range of 70–80 mL. Since ventricular systole began with an EDV of approximately 130 mL of blood, this means that there is still 50–60 mL of blood remaining in the ventricle following contraction. This volume of blood is known as the end systolic volume (ESV). [1]
In normal subjects, the left ventricular ejection fraction (LVEF) should be about 50% [9] (range, 50-80%). There should be no area of abnormal wall motion (hypokinesis, akinesis or dyskinesis). Abnormalities in cardiac function may be manifested as a decrease in LVEF and/or the presence of abnormalities in global and regional wall motion.
R-peak time for right ventricle is measured from leads V1 or V2, where upper range of normal is 35 ms. R wave peak time for left ventricle is measured from lead V5 or V6 and 45 ms is the upper range of normal. [7] R wave peak time is considered to be prolonged if it's more than 45 ms.
Premature ventricular contractions (PVCs), sometimes called ventricular extra beats (VEBs) Premature ventricular beats occurring after every normal beat are termed ventricular bigeminy; PVCs that occur at intervals of 2 normal beats to 1 PVC, or 1 normal beat to 2 PVCs, are termed "PVCs in trigeminy" [13]
An uncoordinated apex beat involving a larger area than normal indicates ventricular dysfunction; such as an aneurysm following myocardial infarction; A pulse deficit between the PMI and periphery may occur in some arrhythmias, such as premature ventricular contraction or atrial fibrillation.