Myocardial beta-adrenoceptor down-regulation early after infarction is associated with long-term incidence of congestive heart failure.
OBJECTIVE
Adverse left ventricular (LV) remodelling after myocardial infarction (MI) frequently leads to congestive heart failure (CHF). We have previously shown that myocardial beta-adrenoceptor density (beta-ARD) is reduced soon after acute MI and correlates with LV dilatation in the short term. The aim of the present study was to determine whether myocardial beta-ARD measured early after MI was associated with progression to CHF in the long term.


RESULTS
We prospectively included 61 consecutive patients (mean age, 52 +/- 11 years, 10 female) in whom MI was the first manifestation of coronary artery disease. Two to 4 weeks after MI, patients underwent positron emission tomography with S-[(11)C]CGP 12177 to measure beta-ARD and (15)O-labelled water to measure myocardial blood flow and coronary flow reserve. Patients were followed-up for a median of 12.7 years (interquartile range, 6.5-13.7 years) and incidence of CHF was recorded. Eleven patients (18%) developed CHF during follow-up. They had lower beta-ARD compared with those who did not (5.35 vs. 6.49 pmol/g, P < 0.001). In patients with myocardial beta-ARD < or =5.57 pmol/g, 10-year CHF incidence rates were higher than in patients with beta-ARD >5.57 pmol/g (57% vs. 9%, P < 0.001). In a Cox regression model, only whole-heart beta-ARD [hazard ratio (HR) 0.29; 95% confidence interval (CI), 0.15-0.58, P < 0.001] and beta-ARD in remote myocardium (HR 0.32; 95% CI, 0.16-0.61, P = 0.001) were significantly associated with the incidence of CHF at follow-up.


CONCLUSIONS
Reduced myocardial beta-ARD early after MI is associated with the incidence of CHF on long-term follow-up.
Gaemperli
Oliver
O
MRC Clinical Sciences Centre, Imperial College and Imperial College NHS Trust, Hammersmith Campus, Du Cane Road, London W12 0NN, UK.
Liga
Riccardo
R
Spyrou
Nicos
N
Rosen
Stuart D
SD
Foale
Rodney
R
Kooner
Jaspal S
JS
Rimoldi
Ornella E
OE
Camici
Paolo G
PG
D000319:Adrenergic beta-Antagonists; D000328:Adult; D003326:Coronary Circulation / Q000502:physiology; D015536:Down-Regulation; D005260:Female; D006321:Heart / Q000000981:diagnostic imaging; D006333:Heart Failure / Q000209:etiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000150:complications* / Q000378:metabolism; D009206:Myocardium / Q000378:metabolism*; D049268:Positron-Emission Tomography / Q000379:methods; D011412:Propanolamines; D011446:Prospective Studies; D011943:Receptors, Adrenergic, beta / Q000378:metabolism*; D020257:Ventricular Remodeling / Q000502:physiology*
D000319:Adrenergic beta-Antagonists; D011412:Propanolamines; D011943:Receptors, Adrenergic, beta; C033394:CGP 12177