-30 to -90 degree axis detion indicates

Ans. is 'a' i.e., Left Axis Detion Cardiac axis The electrical signal recorded on the electrocardiogram (ECG) contains information relative to direction and magnitude of the various complexes. The average direction of any of the complexes can be determined. Normal Cardiac Axis The normal QRS electrical axis, as established in the frontal plane, is between -30 and 90deg (directed downward or inferior and to the left) in adults. Left Axis Detion An axis between -30deg and -90deg (directed superior and to the left) is termed left axis detion. Right Axis Detion If the axis is between 90deg and 180deg (directed inferior and to the right), then right axis detion is present. Extreme Right Axis Detion An axis between -90' and -180deg (directed superior and to the right) is referred to as extreme right or left axis. Indeterminate If the QRS is equiphasic in all leads with no dominant QRS deflection, it is indeterminate axis. Causes of axis detion include Right axis detion Left axis detion Normal variation (veical hea with an axis of 90deg) Normal variation (physiologic, often with age) Mechanical shifts, such as inspiration and emphysema Mechanical shifts, such as expiration, high diaphragm (pregnancy, ascites, abdominal tumor) Right ventricular hyperophy Left ventricular hyperophy Left posterior fascicular block Left bundle branch block Dextrocardia Left anterior fascicular block Ventricular ectopic rhythms Congenital hea disease (prim um atrial septal Hefect, endocardial cushion defect) Ventricular ectopic rhythms Emphysema Pre-excitation syndrome (Wolff-Parkinson-White Hyperkalemia Lateral wall myocardial infarction Ventricular ectopic rhythms Secundum atrial septal defect Pre-excitation syndromes (Wolff-Parkinson-White Inferior wall myocardial infarction