Massive SVC Thrombus in a Woman With Heterozygous Methyl-Tetrahydrofolate Reductase A1298C Genetic Mutation

Abstract

Some genetic mutations are known to be thrombophilic. Methyltetrahydrofolate reductase (MTHFR) mutations are among the most recently described. Further, large Superior Vena Cava thrombi are a rare occurrence. They are usually discovered in the setting of invasive venous procedures or in patients afflicted with malignancies. Their presentation can be dramatic in the form of Superior Vena Cava Syndrome requiring urgent therapeutic intervention. We present a unique case of a covert large Superior Vena Cava thrombus in a woman diagnosed with heterozygous Methyl-tetrahydrofolate reductase A1298C genetic mutation. She presented with symptoms of bilateral pulmonary embolism requiring urgent thrombolytic intervention. A discussion about the prevalence of Superior Vena Cava thrombi, their risk factors, their possible presentations, diagnostic modalities and therapeutic options follows the presentation.