Indium-111 monoclonal antimyosin cardiac scintigraphy in men with idiopathic dilated cardiomyopathy

Am J Cardiol. 2000 Jan 15;85(2):214-20. doi: 10.1016/s0002-9149(99)00641-4.

Abstract

This study examined the prognostic value and the evolution of the heart-to-lung ratio of monoclonal antimyosin antibody (MAA) uptake in patients with a diagnosis of idiopathic dilated cardiomyopathy (IDC). Uptake of indium-111-labeled MAA occurs when the myocytes become irreversibly damaged. The study included 29 men with IDC followed up for 3 years. The diagnosis was verified by endomyocardial biopsy in all patients. Patients who survived beyond 1 year were restudied. Baseline heart-to-lung ratio of MAA was 1.74+/-0.22. Multivariate Cox regression analysis revealed that MAA and New York Heart Association class were independent predictors of late mortality, with a hazard ratio of 4.4 (95% confidence interval 1.1 to 17.9, p = 0.036) and 7.5 (95% confidence interval 2.0 to 28.4, p = 0.003), respectively, when heart-to-lung ratio of MAA uptake was > 1.74 and New York Heart Association class was >11. When these patients were divided into those with chronic IDC (group I [n = 19]) and those with subacute IDC (group II [n = 10]), baseline heart-to-lung ratio was 1.7+/-0.2 and 1.86+/-0.25, respectively (p = NS). In the surviving patients, on restudy, the heart-to-lung ratio of MAA uptake was unchanged in group I (1.64+/-0.20, p = NS), but had decreased to the level of group I (1.66+/-0.21 [p = 0.008]) in group II. Thus, men with IDC and a high heart-to-lung ratio of MAA uptake have a worse long-term prognosis than patients with a lower ratio. The heart-to-lung ratio of MAA decreases comparably over time in subacute IDC and remains stable in chronic IDC.

MeSH terms

  • Adult
  • Antibodies, Monoclonal / blood
  • Cardiomyopathy, Dilated / diagnostic imaging*
  • Cardiomyopathy, Dilated / immunology
  • Cardiomyopathy, Dilated / physiopathology
  • Follow-Up Studies
  • Humans
  • Indium Radioisotopes*
  • Male
  • Middle Aged
  • Myosins / immunology
  • Prognosis
  • Radionuclide Imaging
  • Risk Factors
  • Severity of Illness Index
  • Ventricular Function, Left

Substances

  • Antibodies, Monoclonal
  • Indium Radioisotopes
  • Myosins