Discussion
IE is a commonly encountered clinical problem, especially in the
patients with predisposing heart disease (1). Most often, the mitral
valve regurgitation in IE is due to the destruction of the valvular
leaflets themselves. The isolated rupture of the antero-lateral
papillary muscle is much rarer and has only been described to the best
of our knowledge in four previous cases (3 - 6). There are many possible
causes of ruptures of papillary muscle in IE that include ischemic
necrosis due to coronary embolism (7), deposition of bacteria due to
aortic regurgitation (8), or direct invasion along the sub-valvular
apparatus by virulent germ like staphylococcus (9). In our case, the
cause of mitral regurgitation was due to direct germ invasion of the
papillary muscle. The transesophageal echocardiography (TEE), with the
trans-gastric view is essential to determine the mechanism of mitral
regurgitation in such cases (10). The ruptured anterolateral papillary
muscle is well-defined as a separate mass attached to the chordae (10).
Although we were unable to show any bacteria on histological examination
and culture of the papillary muscle, active inflammation was a strong
criterion for the IE diagnosis. The absence of isolated germ may be
explained by the use of empiric antibiotics in our patient at admission.
In conclusion, if a huge mass is observed attached to the
mitral apparatus on echocardiography in the case of sepsis, the
diagnosis of IE should be made even in the absence of valvular disease
and the rupture of the papillary muscle in the setting mitral
regurgitation should be considered.
Acknowledgments: None
Conflict of interest: None