Long-term follow-up of global and regional left ventricular function by two-dimensional echocardiography after thrombolytic therapy in acute myocardial infarction.
In order to evaluate changes in left ventricular volumes and regional left ventricular function after thrombolytic therapy in acute myocardial infarction serial two-dimensional echocardiography was performed during a follow-up of 2 years in 206 consecutive patients treated with streptokinase and adjunctive angioplasty in a randomized group of patients. Unexpected progressive left ventricular enlargement was detected both with and without angioplasty. In anterior wall infarction, end-diastolic volume index increased from 55 +/- 14 to 91 +/- 28 ml/m2 (+65%, P < 0.01) and end-systolic volume index increased from 31 +/- 11 to 55 +/- 23 ml/m2 (+79%, P < 0.01), whereas ejection fraction decreased from 45 +/- 9 to 41 +/- 7% (-9%, P = NS). Averaged regional anterior wall motion improved during the first 4 weeks (11 +/- 10 to 16 +/- 12%), but subsequently deteriorated (16 +/- 12 to 10 +/- 6, P < 0.05). The number of segments with pathological wall motion increased. Similar volumetric and regional wall motion data were demonstrated in inferior wall infarction. We believe this reflects a chronic ventricular remodelling phenomenon. This process takes place predominantly during the first 3 months, but continues over the whole follow-up period. Forty percent of the patients suffered symptoms of heart failure on long-term follow-up. Attenuation of progressive ventricular enlargement remains a therapeutic challenge in the long-term care of these patients. Angiotensin-converting enzyme inhibitors are promising agents in this regard.