Grigioni, Francesco

Background —Myocardial infarction (MI) can directly cause ischemic mitral regurgitation (IMR), which has been touted as an indicator of poor prognosis in acute and early phases after MI. However, in the chronic post-MI phase, prognostic implications of IMR presence and degree are poorly defined. Methods and Results —We analyzed 303 patients with previous (>16 days) Q-wave MI by ECG who underwent transthoracic echocardiography: 194 with IMR quantitatively assessed in routine practice and 109 without IMR matched for baseline age (71±11 versus 70±9 years, P =0.20), sex, and ejection fraction (EF, 33±14% versus 34±11%, P =0.14). In IMR patients, regurgitant volume (RVol) and effective regurgitant orifice (ERO) area were 36±24 mL/beat and 21±12 mm 2 , respectively. After 5 years, total mortality and cardiac mortality for patients with IMR (62±5% and 50±6%, respectively) were higher than for those without IMR (39±6% and 30±5%, respectively) (both P <0.001). In multivariate analysis, independently of all baseline characteristics, particularly age and EF, the adjusted relative risks of total and cardiac mortality associated with the presence of IMR (1.88, P =0.003 and 1.83, P =0.014, respectively) and quantified degree of IMR defined by RVol ≥30 mL (2.05, P =0.002 and 2.01, P =0.009) and by ERO ≥20 mm 2 (2.23, P =0.003 and 2.38, P =0.004) were high. Conclusions —In the chronic phase after MI, IMR presence is associated with excess mortality independently of baseline characteristics and degree of ventricular dysfunction. The mortality risk is related directly to the degree of IMR as defined by ERO and RVol. Therefore, IMR detection and quantification provide major information for risk stratification and clinical decision making in the chronic post-MI phase.

Background— Left atrium (LA) enlargement is common in organic mitral regurgitation (MR) and is an emerging prognostic indicator. However, outcome implications of LA enlargement have not been analyzed in the context of routine clinical practice and in a multicenter study. Methods and Results— The Mitral Regurgitation International DAtabase (MIDA) registry enrolls patients with organic MR due to flail leaflets, diagnosed in routine clinical practice, in 5 US and European centers. We investigated the relation between LA diameter and mortality under medical treatment and after mitral surgery in 788 patients in sinus rhythm (64±12 years; median LA, 48 [43 to 52] mm). LA diameter was independently associated with survival after diagnosis (hazard ratio, 1.08 [1.04 to 1.12] per 1 mm increment). Compared with patients with LA <55 mm, those with LA ≥55 mm had lower 8-year overall survival ( P <0.001). LA ≥55 mm independently predicted overall mortality (hazard ratio, 3.67 [1.95 to 6.88]) and cardiac mortality (hazard ratio, 3.74 [1.72 to 8.13]) under medical treatment. The association of LA ≥55 mm and mortality was consistent in subgroups. Similar excess mortality associated with LA ≥55 mm was observed in asymptomatic and symptomatic patients ( P for interaction, 0.77). In patients who underwent mitral surgery, LA ≥55 mm had no impact on postoperative outcome ( P >0.20). Mitral surgery was associated with greater survival benefit in patients with LA ≥55 mm compared with LA <55 mm ( P for interaction, 0.008). Conclusions— In MR caused by flail leaflets, LA diameter ≥55 mm is associated with increased mortality under medical treatment, independent of the presence of symptoms or left ventricular dysfunction.

Background— Papillary muscle rupture (PMR) is an infrequent but catastrophic complication of acute myocardial infarction (MI). Although always considered, surgical treatment is often denied because of high operative mortality. Moreover, the effects of surgery for PMR on long-term outcome, particularly compared with expected outcome after MI, are undefined. Methods and Results— Fifty-four consecutive patients (age, 70±8 years; 74% male) underwent mitral surgery for post-MI PMR from January 1980 through December 2000. Severe presentation (cardiogenic shock, pulmonary edema, or cardiac arrest) was noted in 91% preoperatively. Performance of coronary artery bypass graft was associated with lower operative mortality (odds ratio, 0.18; 95% CI, 0.04 to 0.83; P =0.011), whereas there was a trend for lower mortality after surgery after 1990 (odds ratio, 0.28; 95% CI, 0.06 to 1.3). Thus, operative mortality (overall, 18.5%) decreased from 67% up to 1990 without coronary artery bypass graft to 8.7% after 1990 with coronary artery bypass graft. Overall 5-year survival was 65±7%, and survival free of congestive heart failure was 52±7%. Five-year survival of 30-day operative survivors was 79±4%, identical ( P =0.24) to that of matched controls with MI (similar age, sex, ejection fraction, MI location, and MI year). Survival free of congestive heart failure was similar in PMR cases and MI controls (10-year survival, 28±8% versus 36±6%; P =0.46). Conclusions— Surgery for post-MI PMR involves a notable operative mortality, but there are recent trends for lower operative risk, particularly with associated coronary artery bypass graft. Long term after surgery, outcome is restored to that of similar MI without PMR. These encouraging observations emphasize the importance of prompt diagnosis and aggressive therapeutic approach for patients incurring PMR after MI.