INTRODUCTION:Migration of IVC filters to the heart or the pulmonary artery has been rarely reported. We present a case report of migartion to the pulmonary artery and we review the literature.
CASE PRESENTATION:A 53-year-old male presented to an outside hospital with a complaint of progressive shortness of breath beginning 4 days earlier. He had a history of PE Three years previously, and had been diagnosed with protein S deficiency and was subsequently treated with warfarin. Medical therapy had been stopped and an (IVC) filter was placed 6 months prior to the current presentation due to an orthopedic procedure. A chest XRay and chest CT demonstrated an IVC filter wedged in the proximal right PA. He was subsequently transferred to our tertiary care facility. A trans-thoracic echocardiogram showed severe tricuspid regurgitation with an estimated PA systolic pressure of 50 mmHg, a mildly dilated right atrium and a significant right to left interatrial shunt. Non-contrast chest CT demonstrated an IVC filter wedged in the proximal right PA. Cardiac catheterization was performed in anticipation of filter retrieval. The angiogram showed a large clot within and encasing the filter with minimal flow distally. Due to the size and presence of the clot, the attempted percutanoeus filter retrieval was aborted .The next day; the patient underwent open thoracotomy and cardio-pulmonary bypass with successful surgical removal of the IVC filter and intra-operative atrial septal defect correction. The patient tolerated the procedure well and was extubated the following day.
DISCUSSIONS:In 1972, the Greenfield filter was introduced to replace the Mobin-Uddin umbrella that was associated with high venal caval occlusion rates and serious complications from migration. More recently, filter migration (change in position > 1 cm), either cranially or caudally, has been reported to occur in 5% of filters. A review of the literature revealed a total of 37 cases of intracardiac or intrapulmonary migration with the currently available filters. Sixteen were inadvertently deployed in the heart at the time of insertion, 14 migrated to the heart after IVC placement, and seven migrated to the PA. Twelve patients were asymptomatic, 15 presented with manifestations related to the IVC migration or misplacement, and in 9 cases there was no mention of symptomatology. Scurr et al reported one death in the but this was reportedly of causes not related to the intracardiac filter misplacement. Over the years a variety of techniques to remove or reposition filters have been employed. In 1977, Greenfield et al were the first to report the surgical removal of an IVC filter. Since then operative filter removal has been reported in 14 patients, 13 from the heart and one from the pulmonary artery. Our case represents only the second one we are aware of reporting attempted operative removal of an IVC filter from the PA. The indications for removal most commonly are cardiac (cardiac arrhythmias, hypotension, valvular dysfunction and myocardial infarction) followed by respiratory complications (hypoxemia and dyspnea). The presence of large emboli embedded in the filter and obstructing the PA is also an important indication for removal.
CONCLUSION:Migration of newer design filters is associated with less serious sequelae. This may support the adoption of a more conservative approach such as observation since about half of the patients with reported IVC filter migration do not have any clinical manifestations related to this phenomenon. In the event that filter removal is felt to be warranted, various percutanoeus techniques are available for use before surgical removal becomes necessary.
DISCLOSURE:Wissam Abouzgheib, None.