Discrepancy in blood pressure between the left and right arms - importance of clinical diagnosis and role of radiological imaging

ABSTRACT

Introduction: Differences in systolic blood pressure reading between arms are common but could signal trouble if the discrepancy is significant. Early detection of aortic dissection could invariably determine patient’s survivability. Hence, a high index of suspicion with prompt diagnostic imaging is vital for accurate diagnosis. Case Presentation: A previously healthy 35-year-old lady was referred from district hospital for hypertensive cardiomyopathy complicated by acute pulmonary oedema. After being admitted to the Intensive Care Unit, the mean arterial pressure on the left arm was noted to be significant higher. On physical examination, both lower limbs were dusky in appearance because of poor perfusion. Investigations: Computed Tomography Angiography showed extensive arch and abdominal aorta dissection extending to the proximal common carotid artery. There was distal abdominal aorta thrombosis with partial left renal infarction. Echocardiogram showed global hypokinesia, presence of intimal flap, aortic regurgitation and mild pericardial effusion. Supine chest X-ray showed apparent cardiomegaly. Treatment: Repair of the ascending aortic dissection and suspension of the aortic valve by the cardiothoracic team on Day 2 of admission. The vascular team did bilateral high above knee amputation on Day 9 of admission. Outcome: Patient passed away on Day 10 of admission. Discussion: With the absence of classical features of aortic dissection, establishing the diagnosis can be challenging and requires both good clinical judgment and prompt radiological imaging, such that early treatment can be initiated. Conclusion: A high index of suspicion and good clinical judgment is needed in cases of significant blood pressure discrepancy between arms.