Effect of mitral inflow pattern on diagnosis of severe mitral regurgitation in patients with chronic organic mitral regurgitation

Abstract

Background: To determine sensitivity and specificity of E wave velocity in patients with severe chronic organic mitral regurgitation (MR) and normal left ventricular ejection fraction (EF) and to evaluate prevalence of A wave dominance in patients with severe MR.

Methods: We compared 35 patients with quantified severe, chronic, quantified, organic MR due to flail/prolapsed leaflets who had reparative surgery with 35 age-matched control subjects.

Exclusion criteria: EF < 60%, atrial fibrillation, and more than mild aortic regurgitation.

Results: Mean [standard deviation (SD)] age [70 (8) years vs. 69 (8) years; p = 0.94] and mean (SD) EF [66% (6%) vs. 65% (4%); p = 0.43] were not different between the two groups. Mean (SD) E wave velocity was greater in case patients than control subjects [1.2 (0.3) m/sec vs. 0.7 (0.15) m/sec; p < 0.001]. However, E wave velocity of 1.2 m/sec had a sensitivity of only 57% [95% confidence interval (CI), 41-7 and a specificity of 100% (95% CI, 90-100%) in identifying severe MR. E wave velocity of 0.9 m/sec had a more optimal combined sensitivity (89%; 95% CI, 74-95%) and specificity (86%; 95% CI, 71-94%). A wave dominance was seen in 18% of case patients and 66% of control subjects (p < 0.001).

Conclusion: E wave velocity of 1.2 m/sec is specific not sensitive for severe organic MR; E wave velocity of 0.9 m/sec has better sensitivity and specificity. A wave dominance pattern alone cannot exclude patients with severe organic MR. Our findings highlight the importance of a comprehensive echocardiographic exam rather than relying on a few Doppler parameters in diagnosing MR.

Keywords: A wave velocity; Diastolic function; E wave velocity; Severe mitral regurgitation.

Fig. 1

E wave velocity between patients with no or mild mitral regurgitation (MR) compared with those who have severe MR. Those with no or mild MR were more likely to have an E wave velocity less than 1.2 m/sec. However, those with severe MR were noted to have wide variations in the E wave velocity. In fact, E wave velocity greater than 1.2 m/sec was specific in eliminating severe MR, yet it was not sensitive enough because some patients with severe MR still had E wave velocities less than 1.2 m/sec. Error bars indicate the range of E wave velocities in the control group and the case group. The boxed area shows the E wave velocities of the majority of subjects.

Fig. 2

Illustrative case of a patient with ruptured chords by transthoracic (A) and transesophageal echocardiogram (B)demonstrated by the white arrows. Quantitation of mitral regurgitation by proximal isovelocity surface area method (C) showed the regurgitant volume to be 67 mL [mitral regurgitation (MR) peak velocity Doppler profile not shown]. Even though this patient had severe MR, the mitral inflow pattern did not demonstrate an E wave > 1.2 m/sec (D).

Fig. 3

Receiver operator curve. The receiver operator curve demonstrates that an E wave velocity (E) of 1.2 m/sec had good specificity but low sensitivity in identifying patients with severe mitral regurgitation. However, an E of 0.9 m/sec had better sensitivity and better specificity. AUC: area under the curve.

Fig. 4

A-wave dominant pattern between case patients and control patients. Patients with no or mild mitral regurgitation (MR) are more than likely to have an A wave-dominant pattern than those with severe MR. However, 18% of the patients with severe MR also showed an A wave dominance.