AUTHOR=Berrill Max , Beeton Ian , Fluck David , John Isaac , Lazariashvili Otar , Stewart Jack , Ashcroft Eshan , Belsey Jonathan , Sharma Pankaj , Baltabaeva Aigul 

TITLE=Disproportionate Mitral Regurgitation Determines Survival in Acute Heart Failure

JOURNAL=Frontiers in Cardiovascular Medicine

VOLUME=Volume 8 - 2021

YEAR=2021

URL=https://www.frontiersin.org/journals/cardiovascular-medicine/articles/10.3389/fcvm.2021.742224

DOI=10.3389/fcvm.2021.742224

ISSN=2297-055X

ABSTRACT=Objectives: To assess the prevalence and impact of MR on survival in patients presenting to hospital in AHF using traditional echocardiographic assessment alongside more novel indices of proportionality.

Background It remains unclear if the severity of mitral regurgitation (MR) plays a significant role in determining outcomes in acute heart failure (AHF). There is also uncertainty as to the clinical relevance of indexing MR to left ventricular volumes. This concept of disproportionality has not been assessed in AHF.

Methods 418 consecutive patients presenting in AHF over 12 months were recruited and followed up for 2 years. MR was quantitatively assessed within 24 hours of recruitment. Standard proximal isovelocity surface area (PISA) and a novel proportionality index of effective regurgitant orifice/left ventricular end-diastolic volume (ERO/LVEDV) >0.14mm2/ml were used to identify severe and disproportionate MR.  

Results: Every patient had MR. 331/418 (78.9%) were quantifiable by PISA. 165/418 (39.5%) displayed significant MR. A larger cohort displayed disproportionate MR defined by either a proportionality index using ERO/LVEDV >0.14 mm2/ml or regurgitant volumes/LVEDV >0.2 (217/331 (65.6%) and 222/345 (64.3%) respectively). The LVEDV was enlarged in significant MR - 129.5±58.95ml vs. 100.0±49.91ml in mild, [p<0.0001], but remained within the normal range. Significant MR was associated with a greater mortality at 2 years (44.2% vs. 34.8% in mild MR [HR 1.39; 95% CI: 1.01-1.92,p=0.04]), which persisted with adjustment for comorbid conditions (HR; 1.43; 95% CI: 1.04-1.97, p=0.03).  Disproportionate MR defined by ERO/LVEDV >0.14 mm2/ml was also associated with worse outcome (42.4% vs. 28.3% [HR 1.62; 95% CI 1.12-2.34, p=0.01]).

Conclusions MR was a universal feature in AHF and determines outcome in significant cases. Furthermore, disproportionate MR, defined either by EROA or volumetrically, is associated with worse prognosis despite the absence of adverse LV remodelling. These findings outline the importance of adjusting acute volume overload to LV volumes and calls for a review of the current standards of MR assessment.

Trial registration number: NCT02728739. https://clinicaltrials.gov/ct2/show/NCT02728739