Serum amyloid type A may be a predictor of restenosis.
BACKGROUND
Elevation of acute phase proteins [C-reactive protein (CRP) and serum amyloid type A (SAA)] has been demonstrated in unstable angina with an adverse clinical prognosis.


OBJECTIVE
The study was undertaken to determine the effect of angioplasty on the levels of SAA and the correlation with postangioplasty restenosis.


METHODS
In a university-affiliated tertiary medical center, a prospective case study was undertaken in 55 patients who underwent successful percutaneous transluminal coronary angioplasty (PTCA) of a single coronary lesion for angina pectoris. Three groups of patients were clinically characterized according to Braunwald's classification of anginal syndrome: Group A: class III; Group B: class I; Group C: stable angina. Serum amyloid type A was measured by an ELISA method before PTCA and after 24 h, 1, and 3 months. Patients were followed clinically for 12 months. A thallium stress perfusion scan was performed 3 months after PTCA and coronary angiography was repeated in patients with an abnormal thallium perfusion scan.


RESULTS
Serum amyloid type A levels > 100 micrograms/ml could identify Group A patients with a high sensitivity and specificity (r = 0.85 and 0.86, respectively). Of the patients studied, 75% increased their SAA level 24 h after angioplasty. An increase of SAA by > 100% was associated with an increased risk of restenosis, with a relative risk of 6.4 (p < 0.05).


CONCLUSIONS
Increased levels of SAA characterize patients with unstable angina pectoris with a high specificity and sensitivity. Levels of SAA that increase > 100% 24 h after angioplasty may serve as a marker of restenosis.
Blum
A
A
Department of Cardiology, Tel-Aviv Medical Center, Israel.
Kaplan
G
G
Vardinon
N
N
Yust
I
I
Burke
M
M
Laniado
S
S
Miller
H
H
D000328:Adult; D000368:Aged; D000787:Angina Pectoris / Q000097:blood* / Q000145:classification*; D000789:Angina, Unstable / Q000097:blood / Q000145:classification; D015906:Angioplasty, Balloon, Coronary / Q000379:methods; D015415:Biomarkers / Q000097:blood; D016022:Case-Control Studies; D017023:Coronary Angiography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012008:Recurrence; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D000685:Serum Amyloid A Protein / Q000032:analysis*; D018709:Statistics, Nonparametric; D013794:Thallium Radioisotopes
D015415:Biomarkers; D000685:Serum Amyloid A Protein; D013794:Thallium Radioisotopes