Enriquez-Sarano, Maurice

Background and Purpose— Association of mitral valve prolapse (MVP) with ischemic neurological events (INEs) is uncertain. Methods— In the community of Olmsted County (Minn), we identified all MVP diagnosed (1989 to 1998) in patients in sinus rhythm with no prior history of INE. We measured INE rates and compared them with expected rates in our community to define the excess risk of INE. Results— Among 777 eligible subjects (age, 49±20 years; 66% female; follow-up, 5.5±3.0 years), 30 patients had at least 1 INE during follow-up (at 10 years, 7±1%). Compared with expected INEs in the same community, subjects with MVP showed excess risk of lifetime INE (relative risk [RR], 2.2; 95% CI, 1.5 to 3.2; P <0.001) and during follow-up under purely medical management (RR, 1.8; 95% CI, 1.1 to 2.8; P =0.009). Independent determinants of INE were older age (RR, 1.08 per year; 95% CI, 1.04 to 1.11; P <0.001), mitral thickening (RR, 3.2; 95% CI, 1.4 to 7.4; P =0.008), atrial fibrillation (AFib) during follow-up (RR, 4.3; 95% CI, 1.9 to 10.0; P <0.001), and need for cardiac surgery (RR, 2.5; 95% CI, 1.1 to 5.8; P =0.03). INE 10-year rates were low in patients <50 years of age (0.4±0.4%, P =0.60 versus expected) but were excessive in patients >50 years of age (16±3%, P <0.001 versus expected) or with thickened leaflets (7±2%, P <0.001 versus expected). Predictors of follow-up AFib were age, mitral regurgitation, and left atrium diameter (all P <0.01). Conclusions— In the community, subjects with MVP display a lifetime excess rate of INE compared with expected. Clinical (older age) and echocardiographic (leaflets thickening) characteristics define patients with MVP at high risk for INE, and subsequent AFib or need for cardiac surgery, both related to the degree of mitral regurgitation, increase the risk of INE.

Objective— This study was undertaken to examine the association between bicuspid aortic valve (BAV) and aortic dilatation in the community. The association between BAV and aortic dilatation has been reported predominantly in retrospective studies in patients mostly with valvular dysfunction or selected surgical patients from tertiary referral centers. An independent association of BAV and aortic dilatation in a community-based study has not been demonstrated. Methods and Results— In a geographically defined population of Olmsted County, Minnesota, residents with BAV (n=44, age 35±13 years) without hemodynamically significant obstruction or regurgitation and matched controls with normal tricuspid aortic valves were identified by transthoracic echocardiography. The two groups were compared with respect to measurements of the aorta. The BAV and control groups differed with respect to size of the aortic anulus (23.2±2.4 versus 21.6±2.4 mm; P =0.002), aortic sinus (33.5±4.6 versus 30.3±4.1 mm; P =0.0001), and proximal ascending aorta (33.3±6.5 versus 27.9±3.6 mm; P =0.0001). There was no difference in the size of the aortic arch (24.2±3.6 versus 25.3±3.4 mm; P =0.16). These differences were maintained when the groups were stratified by sex and blood pressure. The relationship between bicuspid aortic valve and aortic dilatation was maintained when adjusting for factors related to fluid mechanics and hemodynamics such as systolic blood pressure, diastolic blood pressure, left ventricular ejection time, and peak aortic valve velocity. Conclusions— In a community-based study, BAV is associated with an alteration of aortic dimensions even in the absence of hemodynamically significant aortic valve stenosis or regurgitation.

Background— Left ventricular dysfunction is an indication for aortic valve replacement (AVR) in patients with severe aortic regurgitation (AR). However, the postoperative outcome of patients with severe AR and a markedly low ejection fraction (EF) is not known. Methods and Results— The study group consisted of a total of 450 patients who had AVR for isolated AR between 1980 and 1995. Patients with markedly reduced left ventricular function (EF <35%, LoEF, n=43) were compared with those with moderate reduction in left ventricular function (EF 35% to 50%, MedEF, n=134) and those with normal left ventricular function (EF ≥50%, Nl EF, n=273). The operative mortality rate was higher with LoEF (14%) than with MedEF and Nl EF (6.7% and 3.7%, respectively, P =0.02). At 10 years, 41%±9% of LoEF patients had survived compared with 56%±5% and 70%±3% of MedEF and Nl EF patients, respectively ( P <0.0001). Congestive heart failure occurred at 10 years in 25%±9% with LoEF compared with 17%±4% and 9%±2% with MedEF and NL EF, respectively ( P <0.003). Postoperative EF improved by 4.9%±13.8% in the LoEF group and by 4%±11.9% in the MedEF group compared with −2.3%±10.9% in the Nl EF group ( P <0.002 and P <0.0001, respectively). Conclusions— Patients with severe AR and markedly low EF incur excess operative mortality rates, postoperative mortality rates, and congestive heart failure after AVR. However, postoperative EF improves markedly, and most patients enjoy a long postoperative survival without recurrence of heart failure after AVR; thus they should not be denied the benefits of AVR.

Background— The outcome of mitral valve prolapse (MVP) is controversial, with marked discrepancies in reported complication rates. Methods and Results— We conducted a community study of all Olmsted County, Minn, residents first diagnosed with asymptomatic MVP between 1989 and 1998 (N=833). Diagnosis, motivated by auscultatory findings (n=557) or incidental (n=276), was always confirmed by echocardiography with the use of current criteria. End points analyzed during 4581 person-years of follow-up were mortality (n=96, 19±2% at 10 years), cardiovascular morbidity (n=171), and MVP-related events (n=109, 20±2% at 10 years). The most frequent primary risk factors for cardiovascular mortality were mitral regurgitation from moderate to severe ( P =0.002, n=131) and, less frequently, ejection fraction <50% ( P =0.003, n=31). Secondary risk factors independently predictive of cardiovascular morbidity were slight mitral regurgitation, left atrium ≥40 mm, flail leaflet, atrial fibrillation, and age ≥50 years (all P <0.01). Patients with only 0 or 1 secondary risk factor (n=430) had excellent outcome, with 10-year mortality of 5±2% ( P =0.17 versus expected), cardiovascular morbidity of 0.5%/y, and MVP-related events of 0.2%/y. Patients with ≥2 secondary risk factors (n=250) had mortality similar to expected ( P =0.20) but high cardiovascular morbidity (6.2%/y, P <0.01) and notable MVP-related events (1.7%/y, P <0.01). Patients with primary risk factors (n=153) showed excess 10-year mortality (45±9%, P =0.01 versus expected), high morbidity (18.5%/y, P <0.01), and high MVP-related events (15%/y, P <0.01). Conclusions— Natural history of asymptomatic MVP in the community is widely heterogeneous and may be severe. Clinical and echocardiographic characteristics allow separation of the majority of patients with excellent prognosis from subsets of patients displaying, during follow-up, high morbidity or even excess mortality as direct a consequence of MVP.