Non-Contrast MR Pulmonary Angiogram in the diagnosis of Acute Pulmonary Thromboembolism in Chronic Kidney Disease - Preventing Insult to Injury.

Computed tomography pulmonary angiography (CTPA) remains the imaging modality of choice for diagnosing acute pulmonary thrombo-embolism (PTE). However, the evaluation of kidney function should be a mandatory step prior to the administration of any contrast media, as iodinated contrast requires careful risk stratification in patients with pre-existing kidney impairment. We present a 72-year-old male with stage G4 chronic kidney disease (CKD), obesity, diabetes and hypertension with history of acute worsening of dyspnoea. Clinical findings, which included tachycardia, hypoxia and a new diagnosis of femoral deep vein thrombosis (DVT), strongly suggested acute pulmonary thrombo-embolism (PTE). Given an estimated glomerular filtration rate (eGFR) of 16 mL/min/1.73 m2, standard CTPA was precluded to avoid risk of contrast-induced acute kidney injury. Non-contrast magnetic resonance pulmonary angiography (MRPA) using a balanced turbo field echo (BTFE) sequence successfully identified bilateral main pulmonary artery thrombi. Following thrombolysis and serial MRPA monitoring, the patient achieved hemodynamic stability without renal deterioration. This case report serves to highlight the utility of non-contrast MRPA, as an effective imaging modality for evaluating the pulmonary arteries in patients with kidney disease.