A 66 year old lady who underwent an uncomplicated hemicolectomy for colo-rectal carcinoma last week is brought in complaining of sudden onset dyspnea of 2 hours duration. There is no associated fever, cough, chest pain, nausea, vomiting, faintishness or calf pain. She has no comorbidities and this is her first such episode. She does not smoke and is only on acetaminophen (paracetamol), for analgesia.
Serial ECGs are only positive for sinus tachycardia.
The Troponin T assay comes as negative.
D-Dimers are elevated.
CT pulmonary angiography shows a filling defect involving the arterial tree of the left lower lobe.