Electrocardiographic low-frequency QRS notching and ventilatory impairment in patients with pulmonary tuberculosis.

The occurrence of notching in the initial and terminal parts of the QRS complex of the ECG was studied in a series of 1072 patients with active or healed pulmonary tuberculosis. Terminal notchings were associated with ventilatory impairment: in the male group the percentage of patients with terminal notching increased from 5 to 20% as the FEV1.0% decreased from larger than or equal to 80 to below 40. Initial notchings were not associated with ventilatory impairment. The relationships were similar when studied separately in groups with and without left heart disease.