Relation between left atrial strain and exercise tolerance in patients with mild mitral stenosis: An insight from 2D speckle‐tracking echocardiography

Abstract

Background Mild mitral stenosis (MS) is a progressive disease but unfortunately, its clinical course is still unclearly studied. We aimed to study the left atrial (LA) deformation in such patients and how it is related to exercise intolerance. Methods Seventy‐five patients with mitral valve area of 1.81 ± 0.13 cm2 and 40 healthy control subjects were enrolled. All participants had sinus rhythm, and they underwent conventional echocardiography and LA strain analysis with speckle‐tracking study. The following parameters were obtained: left atrial reservoir strain (LAS‐s), LA conduit strain (LAS‐e), and LA contraction strain (LAS‐a). All participants underwent symptoms limited stress ECG using modified Bruce protocol. Results Comparing with control subjects, patients with mild MS had significant lower LAS‐s value (P < .01) and LAS‐e (<0.03). Patients with exercise intolerance (METs < 8) had lower LAS‐s (P < .001), LAS‐e (P < .01), and LAS‐a (P < .05) values compared to those with METs ≥ 8. We found that METs was significantly related to LAS‐s (P < .001), brain natriuretic peptide (P < .001), and Δ TAPSE (P < .03). Multivariate analysis showed that LAS‐s was an independent predictor of reduced exercise capacity. With ROC analysis, LAS‐s ≤ 26.5% was the optimal value for prediction of exercise intolerance in patients with mild MS. Conclusion A significant percentage of patients with mild mitral stenosis had exercise intolerance. We found that LAS‐s was significantly associated with exercise capacity in patients with mild MS. Hence, we thought that LA deformation could be of great value in the follow‐up of patients with mild MS.

Cardiac Imaging for the Assessment of Left Atrial Mechanics Across Heart Failure Stages

“…Mahfouz et al performed stress echocardiography to assess exercise intolerance in 75 patients with MV area of 1.81 ± 0.13 cm 2 and compared them with 40 healthy control subjects. Interestingly, 44% of asymptomatic patients with mild MS had exercise intolerance, and reservoir strain was significantly associated with exercise capacity in patients with mild MS (cut-off value: reservoir strain ≤ 26.5%) ( 46 ). Similarly, Chien et al investigated the relationship between LA deformation as measured by 2DSTE derived LA strain and HF symptoms in 69 subjects with rheumatic MS, and found that NYHA class independently correlated with LA reservoir strain and reservoir strain rate ( 149 ).…”

Left Atrial Function by Two-Dimensional Speckle Tracking Echocardiography in Patients with Severe Rheumatic Mitral Stenosis and Pulmonary Hypertension

“…reservoir, conduit and contractile strain suggestive of severe LA dysfunction in patients with severe rheumatic MS when compared to healthy controls. It has been shown in a previous study by Mahfouz et al 17 on 75 patients that the conduit and reservoir function are affected in mild MS while LA contractile strain is well preserved. The increased LA contractile function appears as a compensatory mechanism to counterbalance reduced LA reservoir and conduit function in mild MS as LV filling predominantly occurs in LA contractile phase in MS in contrast to normal filling pattern where LA filling predominantly occurs in the early conduit phase.…”

Left atrial function by two-dimensional speckle tracking echocardiography in patients with severe rheumatic mitral stenosis and pulmonary hypertension

“…Our study demonstrates a significant decrease in all three left atrial strain parameters i.e. reservoir, conduit and contractile strain signifying severe LA dysfunction in patients with severe rheumatic MS. Mahfouz et al 5 reported that in mild MS, LA conduit and reservoir strain were decreased but the contractile strain was well preserved. Another study by Demirkol et al 6 on 52 asymptomatic MS patients with MVA 1.38 ± 0.36 cm 2 and mean diastolic transmitral gradient 7.9 ± 2.8 mm Hg also reported reduced LA reservoir and conduit strain but increased contractile strain.…”

“…two-dimensional (2D) speckle tracking echocardiography (STE). 4 , 5 , 6 Most previous studies have either assessed global LA strain, reservoir or conduit strain with contractile strain being reported only in mild to moderate MS. 5 , 6 We aimed to assess LA function (reservoir, conduit strain and contractile strain) by STE and its correlation with NYHA functional class and echocardiography parameters in patients with isolated severe MS with pulmonary hypertension and healthy controls.…”