Dyspnoea after dual-chamber pacemaker implantation

A man in his 90s presented to the emergency department after a fall due to a transient loss of consciousness. He had a background of ischaemic heart disease and congestive cardiac failure, but no previous history of falls or syncope. On admission, his heart rate was 98 bpm with a blood pressure of 147/92 mm Hg. An electrocardiogram (ECG) on admission showed trifascicular block.

Given the patient’s presentation and ECG findings, 24-hour ECG monitoring was performed, which demonstrated episodes of bradyarrythmias. A dual-chamber pacemaker was inserted with left subclavian venous access. A chest radiograph five hours after the procedure showed an adequate lead position with no pneumothorax.

Sixteen hours after the procedure, the patient became acutely dyspnoeic with oxygen saturations of 92% on 35% fractional inspired oxygen (FiO₂) and a respiratory rate of 23 breaths per minute. Clinical examination revealed …