Supraventricular tachycardia (SVT) may be associated with pulmonary embolism (PE) and if the underlying diagnosis of PE is missed, the arrhythmia may tend to recur. We present a case of refractory SVT which was due to PE in a patient with ovarian malignancy in the postoperative period. Malignancy is a risk factor for deep vein thrombosis (DVT) and the risk is increased in the postoperative period after prolonged oncological surgeries. This report highlights the need for a high index of suspicion when we encounter refractory cardiac arrhythmias in the perioperative period in patients with increased risk for DVT.