Patterns of left ventricular dilation during the six months after myocardial infarction.
Changes in left ventricular volume after a first myocardial infarction were studied in 50 patients. Serial radionuclide angiograms were obtained 48 h, 10 days and 1 and 6 months after infarction and left ventricular volume measured by a nongeometric method. Left ventricular dilation (greater than or equal to 20% increase in end-diastolic volume) occurred within 10 days of infarction in 11 patients, who had a mean volume increase of 34 +/- 15% (p = 0.002 versus 48 h) at 10 days and 61 +/- 43% (p = 0.01 versus 10 days) at 6 months. Ten other patients manifested left ventricular dilation between 10 days and 6 months with a lesser volume increase of 42 +/- 18% by 6 months. Among the 21 patients with ventricular dilation, progressive dilation (serial volume increases greater than or equal to 20% on two or more occasions) occurred in 8 patients, who all had a large anterior infarct. Mean volume increases at 10 days and 1 and 6 months were 27 +/- 20%, 49 +/- 40% (p = 0.03 versus 10 days) and 79 +/- 37% (p = 0.006 versus 1 month), respectively, in this group. In patients with progressive dilation, left ventricular ejection fraction decreased from 35 +/- 6% at 48 h to 24 +/- 10% at 1 month (p less than 0.001) and 27 +/- 10% (p = 0.006) at 6 months. Between 1 month and 2 years after infarction six patients died, of whom four had progressive dilation.(ABSTRACT TRUNCATED AT 250 WORDS)
Jeremy
R W
RW
Hallstrom Institute of Cardiology, Department of Nuclear Medicine, Royal Prince Alfred Hospital, Camperdown, New South Wales, Australia.
Allman
K C
KC
Bautovitch
G
G
Harris
P J
PJ
D000368:Aged; D002306:Cardiac Volume; D006332:Cardiomegaly / Q000000981:diagnostic imaging / Q000503:physiopathology*; D003971:Diastole; D005260:Female; D005500:Follow-Up Studies; D006339:Heart Rate; D006352:Heart Ventricles / Q000000981:diagnostic imaging / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction; D009203:Myocardial Infarction / Q000000981:diagnostic imaging / Q000503:physiopathology*; D011446:Prospective Studies; D011877:Radionuclide Imaging