Pulsus paradoxus: an underused tool.

A 69-year-old man was brought to the emergency unit at 3 a.m. because of severe chest pain. He had no history of heart disease, chest pain, shortness of breath, palpitations, diabetes, hypertension or hyperlipidaemia, and there was no family history of heart disease. Chest pain was still present on admission. There were no electrocardiographic (ECG) changes diagnostic of acute cardiac ischaemia. Blood pressure (BP) was 170/100 mmHg in both arms, pulse 72 bpm and regular, no fever, and the respiratory rate was 16 breaths/min. Arterial blood gas analysis was not suggestive of pulmonary embolism, and the chest Xray study was normal. While the patient was in the emergency unit, he had a transient loss of consciousness with BP 80/50 mmHg; the ECG morphology remained unchanged with a sinus rhythm at 74 bpm. Within 3 min the patient’s BP spontaneously rose to 140/70 mmHg, and he became fully alert. The peripheral pulses were 2+ in the upper and lower extremities bilaterally. At cardiac examination, the heart tones were distant with no murmur, rubs or gallups. At echocardiography, the left ventricular chamber size was normal with an adequate left ventricular performance. Another possible explanation for the chest pain was aortic dissection; however, the aortic root was normal (36 mm) although an anterior and posterior slight pericardial effusion was present. The patient was then sent to the medical ward for further assessment.