Exercise Testing and Stress Imaging in Mitral Valve Disease

Abstract

Opinion statementMitral valve disease represented by mitral stenosis and mitral regurgitation is the second most frequent valvulopathy. Mitral stenosis leads to an increased left atrial pressure whereas mitral regurgitation leads to an increased left atrial pressure associated with a volume overload. Secondary to an upstream transmission of this overpressure, both mitral stenosis and regurgitation lead to pulmonary hypertension and right heart failure. In addition, mitral regurgitation also leads to left ventricular dilatation and dysfunction with left heart failure. Depending on the anatomy of the valvular and subvalvular apparatus, valve repair (percutaneous mitral commissurotomy for mitral stenosis and valvuloplasty for mitral regurgitation) might be possible. If the anatomy is not favorable, valve replacement by mechanical or biological prosthesis is indicated. Most of the intervention indications are based on clinical symptoms and resting transthoracic echocardiography. Outcomes of patients operated based upon resting echo abnormalities might however not be optimal. Therefore early intervention might be beneficial based upon abnormal exercise testing, which has been demonstrated to more sensitive to identify high-risk patients. In this last decade, especially exercise echocardiography has been found to be a crucial tool in the management of patients with mitral valve disease.

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“…However, both transmitral mean PG and the increase in PASP during exercise depend on atrioventricular compliance. Patients with low atrioventricular compliance (<4 mL/mm Hg) have more frequently dyspnea, lower functional capacity, and greater rise in PASP during exertion …”

“…2 Because PASP is age-dependent, some investigators suggest the increase in relative PASP>90% at 60 W workload as a more sensitive marker. 10 However, both transmitral mean PG and the increase in PASP during exercise depend on atrioventricular compliance. Patients with low atrioventricular compliance (<4 mL/mm Hg) have more frequently dyspnea, lower functional capacity, and greater rise in PASP during exertion.…”

“…MS is characterized as severe after stress testing with the occurrence of symptoms, increase in transmitral mean PG >15 mm Hg on exertion or > 18 mm Hg with dobutamine infusion and an increase in PASP>60 mm Hg . Because PASP is age‐dependent, some investigators suggest the increase in relative PASP>90% at 60 W workload as a more sensitive marker . However, both transmitral mean PG and the increase in PASP during exercise depend on atrioventricular compliance.…”

“…Asymptomatic patients with severe degenerative MR and symptomatic patients with moderate MR, should undergo exercise SE for the assessment of symptoms, severity of MR, LV‐CR, and for risk stratification . SE may identify patients at higher risk who may benefit from early surgery, before the occurrence of symptoms …”

“…Parameters that should be evaluated are CR estimated with Δ in LVEF or GLS during stress, LV end‐systolic and end‐diastolic dimensions, TAPSE for evaluation of RV‐CR, early diastolic transmitral flow velocity/early diastolic mitral annular tissue Doppler velocity (E/e′), estimation of proximal isovelocity surface area (PISA) and vena contracta (VC), MR jet with continuous wave (CW) Doppler, for the quantification of regurgitant volume and regurgitant orifice area (ROA), and TR jet with CW Doppler for estimation of PASP and EIPH . These parameters should be assessed at a heart rate of ~95 to 105/min.…”