A tragedy of modern cardiology: using ejection fraction to gauge left ventricular function in mitral regurgitation

Cardiac Remodeling after Surgical Mitral Valvuloplasty for Barlow's Disease: Is it the Time to Look to the Load?

We present the case of a 48-year-old man referred for a reduced exercise tolerance in whom a bileaflet mitral prolapse (Barlow's disease), associated with flail motion of posterior mitral leaflet and ruptured chordae tendineae and complicated by eccentric severe regurgitation, was incidentally diagnosed. Albeit paucisymptomatic, at echocardiography he showed the signs of LV dysfunction and, accordingly, was underwent surgical mitral valvuloplasty with implantation of the Memo 3D ReChord Ring without complications. We analyzed the changes of echocardiographic parameters of cardiac remodeling from baseline to post operative setting, highlighting the utility of modern imaging tools (strain and myocardial work) in grade to gauge with more sensitivity LV deformation and function in different conditions of pre and afterload and to overcome the limits of ancient ejection fraction. In conclusion, especially LV myocardial work may be a promising and accurate non load dipendent tool to quantify subclinical LV dysfunction, to guide therapeutic decisions and in post-surgical follow up.

Impact of abrupt versus gradual correction of mitral and tricuspid regurgitation: a modelling study

AIMS

Correction of mitral and/or tricuspid regurgitation (MR, TR) frequently leads to poor outcomes in the days following intervention. We sought to understand how abrupt correction of MR and TR affects ventricular load and to investigate if gradual correction is beneficial.

METHODS AND RESULTS

MR and TR were simulated using the CircAdapt cardiovascular system model with effective regurgitant orifice (ERO) areas of 0.5 cm2 and 0.7 cm2. Ventricular and atrial contractility reductions to 40% of normal and pulmonary hypertension were simulated. Abrupt and gradual ERO closure were simulated with homeostatic regulation of blood pressure and volume. Abrupt correction of MR increased left and right ventricular fibre stress by 40% and 15%, respectively, whereas TR correction increased left and right ventricular fibre stress by 26% and 19%, respectively. This spike was followed by a rapid drop in fibre stress. Myocardial dysfunction prolonged the spike but reduced its amplitude. Right ventricular fibre stress increased more with pulmonary hypertension and TR. Gradual correction demonstrated no spike in tissue load.

CONCLUSIONS

Simulations demonstrated that abrupt ERO closure creates a transient increase in ventricular load that is prolonged by worsened myocardial condition and exacerbated by pulmonary hypertension. Gradual closure of the ERO abolishes this spike and merits clinical investigation.

Mitral valve interventions in heart failure

Secondary mitral regurgitation (MR) results from left ventricular dilatation and dysfunction. Quantification of secondary MR is challenging because of the underlying myocardial disease. Clinical and echocardiographic evaluation requires a multi‐parametric approach. Severe secondary MR occurs in up to one‐fourth of patients with heart failure with reduced ejection fraction, which is associated with a mortality rate of 40% to 50% in 3 years. Percutaneous edge‐to‐edge mitral valve repair (MitraClip) has emerged as an alternative to surgical valve repair to improve symptoms, functional capacity, heart failure hospitalizations, and cardiac haemodynamics. Further new transcatheter strategies addressing MR are evolving. The Carillion, Cardioband, and Mitralign devices were designed to reduce the annulus dilatation, which is a frequent and important determinant of secondary MR. Several transcatheter mitral valve replacement systems (Tendyne, CardiAQ‐Edwards, Neovasc, Tiara, Intrepid, Caisson, HighLife, MValve System, and NCSI NaviGate Mitral) are emerging because valve replacement might be more durable compared with valve repair. In small studies, these interventional therapies demonstrated feasibility and efficiency to reduce MR and to improve heart failure symptoms. However, neither transcatheter nor surgical mitral valve repair or replacement has been proven to impact on the prognosis of heart failure patients with severe MR, which remains high with a mortality rate of 14–20% at 1 year. To date, the primary indication for treatment of secondary severe MR is the amelioration of symptoms, reinforcing the value of a Heart Team discussion. Randomized studies to investigate the treatment effect and long‐term outcome for any transcatheter or surgical mitral valve intervention compared with optimized medical treatment are urgently needed and underway.