Acute Effects of Positive Airway Pressure on Functional Mitral Regurgitation in Patients with Systolic Heart Failure

Interventional management of mitral regurgitation and sleep disordered breathing: "Catching two birds with one stone"

Sleep disordered breathing (SDB), mostly constituting of obstructive and central sleep apnea (OSA and CSA, respectively), is highly prevalent in the general population, and even more among patients with cardiovascular disease, heart failure (HF) and valvular heart disease, such as mitral regurgitation (MR). The coexistence of HF, MR and SDB is associated with worse cardiovascular outcomes and increased morbidity and mortality. Pulmonary congestion, as a result of MR, can exaggerate and worsen the clinical status and symptoms of SDB, while OSA and CSA, through various mechanisms that impair left ventricular dynamics, can promote left ventricular remodelling, mitral annulus dilatation and consequently MR. Regarding treatment, positive airway pressure devices used to ameliorate symptoms in SDB also seem to result in a reduction of MR severity, MR jet fraction and an improvement of left ventricular ejection fraction. However, surgical and transcatheter interventions for MR, and especially transcatheter edge to edge mitral valve repair (TEER), seem to also have a positive effect on SDB, by reducing OSA and CSA-related severity indexes and improving symptom control. The purpose of this review is to provide a comprehensive analysis of the common pathophysiology between SDB and MR, as well as to discuss the available evidence regarding the effect of SDB treatment on MR and the effect of mitral valve surgery or transcatheter repair on both OSA and CSA.

What the anaesthesiologist needs to know about heart-lung interactions

The impact of positive pressure ventilation extends the effect on lungs and gas exchange because the altered intra-thoracic pressure conditions influence determinants of cardiovascular function. These mechanisms are called heart-lung interactions, which conceptually can be divided into two components (1) The effect of positive airway pressure on the cardiovascular system, which may be more or less pronounced under various pathologic cardiac conditions, and (2) The effect of cyclic airway pressure swing on the cardiovascular system, which can be useful in the interpretation of the individual patient's current haemodynamic state. It is imperative for the anaesthesiologist to understand the fundamental mechanisms of heart-lung interactions, as they are a foundation for the understanding of optimal, personalised cardiovascular treatment of patients undergoing surgery in general anaesthesia. The aim of this review is thus to describe what the anaesthesiologist needs to know about heart-lung interactions.