The presence or absence of left ventricular dysfunction in chronic obstructive pulmonary disease has been debated for decades. I have reviewed the following evidence pertaining to this topic: (1) left ventricular pathologic abnormalities; (2) the methods used to determine left ventricular performance; (3) specific abnormalities of left ventricular function as revealed by systolic time intervals, left ventricular end-diastolic pressure, ejection fraction, isovolumic indices, and left ventricular function curves; and (4) pertinent experimental data. The bulk of the evidence indicates that the clinical symtoms of left-sided failure are unreliable in those with obstructive disease of the airways and that the great majority of patients have normal left ventricular function, once other causes are excluded. A small group of patients have some abnormalities in left ventricular performance, but these have not been clinically significant. The ultimate importance of such abnormalities awaits future investigation.