Twenty five patients who had undergone conventional coronary arteriography and left ventriculography for suspected coronary artery disease had left ventriculography performed by digital subtraction angiography as outpatients; there were no complications requiring admission to hospital. A catheter was introduced percutaneously and positioned in the superior vena cava; 40-50 ml of contrast medium was injected at 16-18 ml/s. Left ventriculograms were recorded in the 30 degrees right anterior oblique projection. Diagnostic images were recorded in each case. Left ventricular wall movement was assessed as normal in nine patients, globally hypokinetic in 10, and aneurysmal in six. In each case there was agreement between the two methods. Ejection fraction varied between 17% and 78%. It is concluded that digital subtraction angiography provides a reliable assessment of overall left ventricular function and distinguishes between those patients with a potentially resectable lesion and those with global impairment of function.