Contribution of ischemic mitral regurgitation to congestive heart failure after myocardial infarction.
OBJECTIVE
The purpose of this study was to define the contribution of ischemic mitral regurgitation (IMR) to the occurrence of congestive heart failure (CHF) after myocardial infarction (MI).


BACKGROUND
After MI, CHF is a frequent and serious complication, but its determinants and, particularly, the role of IMR are poorly defined.


METHODS
We analyzed 173 asymptomatic patients with previous Q-wave MI (>16 days) with echocardiographic quantitation of IMR (measuring effective regurgitant orifice [ERO] and regurgitant volume). The 102 patients with IMR were matched to 71 patients without IMR for age (71 +/- 11 years vs. 68 +/- 9 years; p = 0.11), gender (76% vs. 82% males; p = 0.41), and left ventricular ejection fraction (EF) (37 +/- 14% vs. 36 +/- 11%; p = 0.92).


RESULTS
Five-year rates of CHF and of CHF or cardiac death (CD) were 36 +/- 5% and 52 +/- 5%, respectively. Independent determinants of CHF were EF, sodium plasma level, and presence and degree of IMR (p < 0.0001). Five-year CHF rates were 18 +/- 5% without mitral regurgitation (MR), 53 +/- 7% with IMR, 46 +/- 9% with ERO 1 to 19 mm(2) and 68 +/- 12% with ERO > or =20 mm(2) (all p < 0.0001). The adjusted relative risk of CHF was 3.65 (95% confidence interval [CI] 1.86 to 7.75) for IMR presence and 4.42 (95% CI 1.9 to 10.5) for ERO > or =20 mm(2). The adjusted relative risk of CHF/CD was 2.97 (95% CI 1.77 to 5.16) for IMR presence and 4.4 (95% CI 2.4 to 8.2) for ERO > or =20 mm(2).


CONCLUSIONS
After MI, incidence of CHF and of CHF/CD are high even in patients with no or minimal symptoms at baseline and are higher in patients with IMR. Congestive heart failure is independently determined by larger ERO of IMR. These data suggest that detecting and quantifying IMR is essential for risk stratification after MI. Value of IMR treatment in improving post-MI outcome should be investigated.
Grigioni
Francesco
F
Division of Cardiovascular Diseases and Internal Medicine, Mayo Clinic and Mayo Foundation, 200 First Street SW, Rochester, MN 55905, USA.
Detaint
Delphine
D
Avierinos
Jean-François
JF
Scott
Christopher
C
Tajik
Jamil
J
Enriquez-Sarano
Maurice
M
D000368:Aged; D000369:Aged, 80 and over; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D006333:Heart Failure / Q000175:diagnosis / Q000209:etiology* / Q000401:mortality; D006801:Humans; D008297:Male; D008875:Middle Aged; D008944:Mitral Valve Insufficiency / Q000150:complications* / Q000000981:diagnostic imaging; D009203:Myocardial Infarction / Q000150:complications* / Q000000981:diagnostic imaging / Q000401:mortality; D012307:Risk Factors; D012720:Severity of Illness Index; D014463:Ultrasonography