Right Side of the Heart Pulmonary Circulation Unit Involvement in Left-Sided Heart Failure

Though long-neglected, the right heart (RH) is now widely accepted as a pivotal player in heart failure (HF) either with reduced (HFrEF) or preserved (HFpEF) ejection fraction. The chronic overload of the pulmonary microcirculation results in an initial phase characterized by right ventricular (RV) hypertrophy, right atrial (RA) dilation, and diastolic dysfunction. This progresses to overt right heart failure (RHF) when RV dilation and systolic dysfunction lead to RV-pulmonary arterial uncoupling with low RV output. In the context of its established relevance to progression of HF, clinicians should consider assessment of the right heart with information from clinical assessment, biomarkers, and imaging. Notably, no single parameter can predict prognosis alone in HF. Assessments should simultaneously encompass RV systolic function, pulmonary pressures, an estimation of RV-PA coupling, and right heart morphology. Despite a large volume of evidence indicating the relevance of right heart function to the clinical syndrome of HF, evidence-based management strategies are lacking. Targeting RH dysfunction in HF should be an objective of future investigations, being an unmet need in the current management of HF.