Abstract 13766: The Use of Echocardiography to Assess Regional Strain Abnormalities in Patients With Chronic Mitral Regurgitation

Abstract

Background: Patients with primary mitral regurgitation (MR) secondary to mitral valve prolapse (MVP) have regional LV fibrosis in myocardial segments adjacent to the posterior papillary muscle detected by MRI not seen in other patients with MR.. Echocardiographically determined strain is associated with LV fibrosis. Patients with chronic MR are generally followed by echocardiography, however no study has utilized echocardiography to examine regional strain variations in these patients. The object of this study was to examine regional myocardial strain in patients with chronic MR with and without MVP. Methods: Patients undergoing routine transthoracic echocardiography for the assessment of chronic severe MR were included. Patients with secondary MR, ejection fraction < 50%, other significant primary valve disease, history of cardiomyopathy, ischemic heart disease, previous cardiac surgery or pacemaker implantation were excluded. The primary MR subjects were be divided into MVP or non-MVP cohorts. MVP was defined as displacement of 1 or both mitral leaflets by at least 2 mm below the mitral annulus in parasternal long-axis view. Global and segmental strain analysis in 17 left ventricular segments was performed offline and results of the MVP and non-MVP groups compared. Results: 28 patients (mean age 63 ±14 yrs ; 23F/5M) of whom 11 had MVP and 17 had non-MVP disease were included in the study. Patients in the MVP group were significantly younger (59.2 ± 16 vs 69 ± 11 p = 0.05) then in the non-MVP group. Standard echocardiographic measurements including ejection fraction were similar except for estimated PA pressure which was lower in the MVP group, (31.3 ± 6.9 vs 42.6 ± 11.9 mmHg p-value = 0.008).Global strain was normal and similar in the two groups (-21.3 ± 4.4% vs -19.9 ± 2.9%; p = 0.30). (Patients with MVP had significantly reduced segmental strain in the inferior basal segment ( -11.2 ± 9.7 in the MVP group, -18 ± 2.6 in the non-MVP group, p-value 0.037). No other segments showed significant differences between the MVP and non-MVP groups Conclusions: Our findings suggest that patients with chronic MR and MVP have significantly reduced echocardiographic strain in the inferior base when compared to patients with MR secondary to other causes.