Outcome reporting for surgical treatment of degenerative mitral valve disease: A systematic review and critical appraisal

OBJECTIVES: Standardized outcome reporting is of critical importance for performance monitoring, improvement of existing techniques and introduction of novel technologies. Whether outcome reporting for surgical treatment of degenerative mitral valve disease complies with the guidelines has not been assessed to date. METHODS: A systematic review of PubMed, EMBASE, Web of Science and the Cochrane Library was conducted for articles published between 1 January 2009 and 7 March 2016. Inclusion criteria were adult patient population (n >- 200) and surgical intervention for degenerative mitral valve disease. The quality of reported outcome was compared with the standard recommended by the guidelines on reporting morbidity and mortality after cardiac valve interventions. RESULTS: Forty-two non-randomized clinical studies were included: 4 provided early and 38 provided early and late outcome data. Early echocardiographic outcome was reported in 49% of studies. Freedom from reintervention, the indication for reintervention and the follow-up echocardiographic outcome were reported in 97%, 59% and 79% of studies providing late outcome data, respectively. The KaplanMeier method was used to assess the freedom from recurrent mitral regurgitation in 60% (18/30) of studies, whereas 7% (2/30) of studies applied a longitudinal data analysis. Recurrent mitral regurgitation was most commonly defined as moderate (Grade 2+; 60%) or severe (Grade 4+; 37%) regurgitation. CONCLUSIONS: There is a significant discordance between the guidelines-based recommendations and actual reporting of outcome for surgical treatment of degenerative mitral valve disease. Better adherence to the guidelines would raise the quality and generalizability of clinical data reporting.