Critical Questions About Left-Sided Infective Endocarditis.

Research in different topics in cardiovascular medicine is evolving rapidly. However, this is not the case for endocarditis, despite its being the cardiovascular disease with the highest mortality and, at the same time, the entity with relatively less scientific evidence supporting its treatment. Many problems are delaying research: it is an uncommon disease, few multicenter registries are ongoing, financing for research in this topic is lacking, randomization is costly, difficult, and considered unethical by some, and conclusions coming from propensity score analysis are taken as if they came from randomized trials. In this review, we put forward the main issues in need of evidence and propose a different approach to advance the understanding of left-sided infective endocarditis. We summarize the limited evidence available, the questions that are pending, and how we should proceed to answer them.