Abnormalities of Q wave in lead III of ECG limb leads are related to physiologic factors such as obesity and pathological factors such as cardiac diseases.
1. Physiological factors: obese patients, it is possible that there will be Q wave abnormalities in lead III, but the cardiac ultrasound or biochemical examination did not find any abnormality, as long as this situation is closely observed, no special treatment is needed.
2. Pathologic factors
(1) Cardiac disease: Abnormal Q wave in lead III on ECG usually indicates myocardial injury or necrosis. The most common causes of myocardial injury and necrosis are acute myocardial infarction, old myocardial infarction, right heart hypertrophy, etc., especially in patients with a history of coronary heart disease.
(2) Pulmonary embolism: Patients with acute pulmonary embolism will also have lead III Q-wave abnormalities. It is necessary to improve D-dimer, pulmonary artery CTA, angiography, cardiac ultrasound and other examinations to clarify the diagnosis.
If physiological factors are excluded, patients with abnormal Q wave in lead III need to be taken seriously, and should go to a regular hospital specialist in time to avoid deterioration of the condition.