Seventy-six-year-old man with progressive dyspnoea.

CLINICAL INTRODUCTION: A 76-year-old man with 50 years of smoking history was diagnosed in 2012 with diffuse interstitial lung disease, with radiological data of usual interstitial pneumonia. He came to the emergency room presenting with progression of dyspnoea for 1 week, concomitant with loss of 5 kg of weight, anorexia and poor general condition. He had tachypnoea at rest (30 breaths/min), peripheral cyanosis, speech interfered by cough and breathlessness, baseline oxygen saturation 90%, heart rate 40 beats/min and blood pressure 130/70 mm Hg. Chest X-ray was performed and there was basal atelectasia of the right lung. ECG and urgent echocardiogram (transthoracic echocardiogram, TTE) were also performed (figure 1).

QUESTION: Which of the following best explains the patient's situation?heartjnl;105/1/74/F1F1F1Figure 1(A) ECG. (B) Long-axis parasternal view from the transthoracic echocardiogram (TTE). (C) Four-chamber view from the TTE.Acute pulmonary embolismNon-ST elevation myocardial infarctionCardiac lymphomaCardiac myxomaMobitz type II AV block.