Left ventricular pseudoaneurysm after mitral valve surgery is a type of rare and lethal condition derived from rupture of LV. It can take place after both mitral valve repair [1] and replacement. The incidence of this complication was 0.56% and the mortality rate was 57.4% [1]. Reoperation, endocarditis, severe annular calcification, poor visualization of the operating field, low-sized LV and oversizing of prosthetic valves are known to be risk factors. Other causes of rupture of the LV free wall include the untethering of the fibrous structures of the LV during resection of mitral leaflets, an increase in LV contractility after aortic crossclamping, enhanced LV wall stress with the support of inotropic agents, and other mechanical trauma between the free wall and the papillary muscles, such as rubber catheter wedging or metal pump suction during valve replacement [2].
Left ventricular pseudoaneurysm develops only when LV rupture is barely contained by adherent pericardium or scar tissue. Left ventricular rupture was classified according to the timing of rupture [3]. Early rupture is defined as occurring in the operating room any time after discontinuation of cardiopulmonary bypass. Delayed rupture manifests in the recovery room usually hours to days postoperatively. Late rupture occurs days to years after the valve replacement and presents as pseudoaneurysm. In consideration of massive bleeding in the operating room and uneventful recovery after surgery in this case, LV rupture was believed to take place in the operating room. Therefore, this case had an early LV rupture which was encapsulated by an LVPA. The early rupture comprises the majority of LV ruptures following MVR. The mortality rate in these patients is extremely high despite early treatment. The majority of LVPA cases that were reported in the literature presented as a late complication after MVR [4,5,6]. This case is exceptionally rare because LVPA developed as a kind of early LV rupture.
Although prompt surgical repair have been recommended as the method of first choice to prevent LVPA rupture, surgical repair may be hesitant because of the high mortality rate. In consideration of her extremely low body mass index and advanced comorbidity in our case, immediate surgery of this LVPA was believed to have an exceedingly high mortality rate. However, the aneurysmal neck and dimension of the LVPA was fortunately small, which made a conservative management feasible and successful despite continuation of warfarin therapy. During the long-term follow-up, the patient showed stable clinical and hemodynamic conditions. This interesting case suggests that conservative treatment can be an alternative in appropriate patients.
Although 30–40% of untreated pseudoaneurysms rupture in the first year [7], the treatment strategy remains controversial [1, 8,9,10]. Surgery is suggested for patients with large or expanding false aneurysms. Conservative strategies yielded positive results in several cases [1, 8,9,10]. Sakai et al. reported that 7 out of 8 patients with a LVPA after mitral valve repair were managed conservatively, and indicated that conservative management may be possible if the pseudoaneurysm is small and its neck is very narrow [9]. Factors that favor a conservative management include high surgical risks, no clinical symptom, small pseudoaneurysm less than 3 cm, small aneurysmal neck and stable echocardiographic and clinical manifestations [10, 11]. Percutaneous approaches to closure of LVPA have recently been described [12, 13]. For a population of elderly, fragile patients with severe comorbidities, percutaneous closure of the LVPA seems to be a viable minimally invasive option. Anatomy, the size and the width of the neck of the LVPA should be considered when an optimal approach is planned. The disadvantage of these devices is the possibility of mechanical compression of adjacent epicardial coronary vessels.
We presented a rare case of conservatively managed LVPA after early LV rupture. This case suggests that medical treatment LVPA patients has a limited but acceptable role in selected and unusual circumstances.
