Anatomy & Physiology第 79 / 100 题
Long-standing untreated hypertension most commonly produces which EKG-related change?
a.Left ventricular hypertrophy with increased QRS voltage in the left-sided leads
b.Absent P waves in every lead
c.A shortened QT interval below 0.20 second
d.Pacemaker spikes before each QRS
解析
Chronic high blood pressure forces the left ventricle to work against increased resistance, so the muscle thickens and generates larger voltage, appearing as tall R waves in the left-sided leads and deep S waves in V1 and V2. Absent P waves indicate atrial fibrillation or a junctional rhythm. A QT under 0.20 second is not a hypertension finding, and pacemaker spikes come from an implanted device.
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