Systolic Time Intervals in Chronic Obstructive Pulmonary Disease
In an attempt to clarify the relationship between left ventricular function and chronic obstructive pulmonary disease (COPD), systolic time intervals (STI) were measured in 12 control subjects and 28 patients with COPD who had only moderate arterial blood gas abnormalities and who had no cardiac symptomatology or clinical evidence of organic heart disease. The patients with COPD were divided into three groups of increasingly severe airway obstruction based on the percent predicted forced expired volume in one second.
Significant differences in pre-ejection period index (PEP1) and left ventricular ejection time index (LVET1) existed between the control subjects and the patients with the most severe lung disease (Group III). A highly significant difference in PEP/LVET existed between these two groups. The abnormalities of STI demonstrated in these patients are characteristic of left ventricular dysfunction and indicate that subclinical left ventricular dysfunction is frequently present in patients with moderate obstructive lung disease.
- Received June 4, 1974.
- Accepted August 12, 1974.
- © 1974 American Heart Association, Inc.