Eclipsed mitral regurgitation and the role of multimodality imaging: a case report

Abstract

Background: Eclipsed mitral regurgitation (MR) is a rare, reversible condition that leads to transient severe MR and acute heart failure in patients with preserved left ventricular (LV) ejection fraction. Its diagnosis is challenging due to its intermittent presentation, necessitating advanced imaging techniques to reveal the underlying pathology.

Case summary: We present a case of a 74-year-old female with recurrent severe MR associated with a non-obstructive lesion in the proximal left anterior descending (LAD) artery. Multimodality imaging played a pivotal role in diagnosing this condition, as conventional vasodilator stress tests failed to uncover the ischaemic mechanism. Exercise stress echocardiography and myocardial perfusion scintigraphy successfully demonstrated a small ischaemic region affecting the mitral valve apparatus, which triggered severe MR during physical exertion. This dynamic ischaemia, undetected by routine tests, was essential in diagnosing the pathophysiology behind the patient's recurrent MR. Following percutaneous coronary intervention (PCI) to the LAD, her symptoms resolved, confirming the ischaemic origin of the MR.

Discussion: This case underscores the critical role of multimodality imaging in revealing the pathophysiology of recurrent MR. Advanced imaging techniques, particularly under physiologic stress, are crucial for diagnosing dynamic ischaemia and its impact on valvular function. By identifying the ischaemic cause of MR, individualized treatment strategies, such as PCI, can be implemented, avoiding unnecessary valve surgery and improving patient outcomes.

Keywords: Acute pulmonary oedema; Coronary vasospasm; Eclipsed MR; Exercise imaging tests; Multimodality imaging; Transient mitral valve regurgitation.

Figure 1

Initial transoesophageal echo and diagnostic coronary angiogram revealing severe mitral valve regurgitation. (A) 0–30 degrees four-chamber view in end-systole revealing coaptation gap of mitral valve leaflets. (B) Same image with colour revealing severe mitral regurgitation. (C) Diagnostic coronary angiogram right anterior oblique cranial view demonstrating 60–70% disease on proximal left anterior descending artery and 70% on ramus intermedius branch (small vessel).

Figure 2

Recurrence of severe mitral regurgitation with validated quantification in transthoracic echocardiogram. (A) Pisa mitral regurgitation 1.1 cm indicating severe regurgitation. (B) Effective regurgitant orifice area and regurgitant volume measured with continuity method. Note that the triangular shaped envelope of mitral regurgitation indicates acute severe mitral regurgitation and that the effective regurgitant orifice area and regurgitant volume could be underestimated since the continuity equation assumes a more uniform flow.

Figure 3

Left ventricular longitudinal strain at baseline and at peak exercise. Mid-apical antero-septal post-systolic shortening at peak stress compared to baseline is demonstrated with arrows. Strain curves normalized after the administration of sublingual nitrates.

Figure 4

Single-photon emission computed tomography with exercise on treadmill. Three per cent area of ischaemia on the apical anterior wall.

Figure 5

Single-photon emission computed tomography with exercise on treadmill post-revascularization.