Charlotte Ebeling Barbier MD, Presenter: Nothing to Disclose

Lars Johansson PhD, Abstract Co-Author: Nothing to Disclose

Lars Lind MD, PhD, Abstract Co-Author: Nothing to Disclose

Håkan Ahlström MD,PhD, Abstract Co-Author: Nothing to Disclose

Tomas Bjerner MD, PhD, Abstract Co-Author: Nothing to Disclose

Clinically unrecognized myocardial infarction (MI) signifies a considerable health risk. Available prevalence estimates are based primarily on Q wave infarctions detected with ECG. Late enhancement magnetic resonance imaging (MRI) can detect acute and healed myocardial infarction and other myocardial scars as hyper-intense areas. This technique also detects non-Q-wave and subendocardial infarctions, which may reveal the prevalence of unrecognized MI to be even greater than available estimates. The aim of this study was to investigate the prevalence of areas of nonviable, hyper-intense myocardium in seventy-year-olds, assessed with MRI.

MRI was performed on 177 subjects in the Uppsala region (86 males, 91 females), who were recruited at seventy years of age. These subjects constitute a subpopulation of an unselected study population of 1016 subjects where 7.1% reported having suffered a MI. Late enhancement images were acquired after injection of 40 ml Gd-DTPA-BMA, using a 3D inversion recovery sequence covering the left ventricular myocardium in short axis view (n=177), and multiple long axis views (n=151). The inversion time was individually adjusted to null viable myocardium for every subject. Areas of hyper-intense myocardium were visually assessed, and classified as transmural or not. The reliability of the assessment was in some cases impaired by technical factors and the assessment was hence rated as reliable or unreliable.

Areas of hyper-intense myocardium were found in 50 subjects (28.2%) and were transmural in 28 cases (15.8%). Twenty of the hyper-intensity assessments were rated as unreliable as were 46 of the remaining assessments. The data from one subject were not assessable due to technical factors.

Areas of nonviable, hyper-intense myocardium were found in more subjects (28.2%) than could be expected from anamnestic data (7.1% reported MI). These areas can represent different abnormalities, one being clinically unrecognized MI.

Ebeling Barbier, C, Johansson, L, Lind, L, Ahlström, H, Bjerner, T, Prevalence of Nonviable Myocardium Assessed with MRI: A Population Study.  Radiological Society of North America 2005 Scientific Assembly and Annual Meeting, November 27 - December 2, 2005 ,Chicago IL. http://archive.rsna.org/2005/4409962.html