74-Year-old female with hemoptysis and left upper lobe infiltrate caused by aortopulmonary fistula

Introduction: The causes of hemoptysis are myriad and include both pulmonary and vascular disorders. The most common etiologies are tuberculosis, bronchiectasis, lung abscess, malignancy and, with increasing frequency, chronic bronchitis. Aorto-pulmonary fistula is a rare complication of aortic aneurysm and aneurysm repair and thus rarely causes hemoptysis. However, if undiagnosed it is a uniformly fatal cause of massive hemoptysis. Case Presentation: A 74-year-old woman was admitted to the hospital after cardiopulmonary resuscitation and endotracheal intubation for massive hemoptysis. On examination, she had a systolic blood pressure of 80 mm Hg, rapid atrial fibrillation, no cardiac murmurs, bilateral inspiratory crackles, and a benign abdomen. Plain chest x-ray (CXR) showed diffuse infiltrates in the left lung and no evidence of aortic aneurysm. Emergent bronchoscopy disclosed a totally obstructing thrombus at the origin of the left main stem bronchus that, when cleared, revealed no active sites of bleeding. Aortogram and bronchial arteriogram revealed only severe atherosclerosis. Other than iron deficiency anemia, the laboratory studies were unremarkable. Arterial blood gases, on 2L O₂ via nasal cannula, were pO₂ - 48, pCO₂ - 34, pH - 7.39, HCO₃ - 20. Before admission, the hemoptysis had been intermittent for two months, with at most, 1 cup of blood-streaked sputum at any time. Prior evaluation including bronchoscopy failed to reveal a bleeding site and computerized tomography (CT) of the chest showed a new infiltrate in the left upper lobe. Past medical history was significant for 100 pack years smoking, proximal descending aortic aneurysm repair (teflon graft, 12 years previously), and chronic obstructive pulmonary disease. There was no history of tuberculosis or bronchiectasis, and she was taking no medications. After cardiorespiratory stabilization, repeat bronchoscopy was again unable to identify a bleeding site. Cultures for bacteria, fungi and mycobacteria and cytology, from bronchial washings, were all negative. Thoracic Surgery was consulted; CT of the chest prior to surgery showed non-specific adherent soft tissue on the superior aspect of the aortic arch. At surgery, the medial portion of the left upper lobe was adherent to the descending aorta distal to the left subclavian artery with no evidence of aortic aneurysm. Near the previous aneurysm repair site, an aorto-pulmonary fistula 1.2X1.0X0.6 cm was isolated and repaired. The adherent lung tissue was resected and friable tissue at the repair site was reinforced with a serratus anterior muscle flap. Ten days postoperatively the patient was dismissed home without complications. Repeat CXR at one month showed complete resolution of lung infiltrates. Discussion: The diagnosis of aorto-pulmonary fistula is difficult to make and requires a high index of suspicion. Less than 50% of cases are diagnosed correctly pre-mortem. If diagnosed, survival is better than 80% but if not, it is uniformly fatal.¹ Patients are usually male, mean age 59 years, and most commonly present with massive hemoptysis. Presentation with chest pain, dyspnea, or cough is seen less commonly (30%-45% of cases).¹ Aneurysmal dilatation of the aorta (secondary to atherosclerosis, grafts, syphilis, and tuberculosis) is the most common cause, but traumatic rupture and acute dissection can also cause fistula formation. Aorto-pulmonary fistulae present 2-15 years after successful thoracic aortic aneurysm graft repair, caused by infection or pulsatile erosion of suture line leaks.² Intermittent hemoptysis of varying quantities of blood commonly heralds the final presentation of massive hemoptysis. This may happen from 2 days to one year, but commonly a few months, before diagnosis.³ A high clinical diagnostic suspicion is supported by CXR, aortogram, CT, or bronchoscopy. Normal radiographic studies do not rule out the diagnosis. Bronchoscopy should proceed with caution so as not to dislodge a clot covering the fistula. Surgery is essential for cure and should be performed immediately after diagnosis. A replacement aortic graft with protection of the suture line by a living tissue flap⁴ and resection of the adherent lung tissue is the most common procedure. Immediate survival is better than 80%; recurrence of the fistula 1-2 years after repair can occur, although this is rare. Conclusion: This case report highlights a number of important diagnostic and management essentials in the approach to massive hemoptysis. Aorto-pulmonary fistula is a rare but significantly treatable cause for hemoptysis. Fistulae occur many years after aortic surgery and a high clinical suspicion must be maintained when a history of intermittent hemoptysis is obtained in patients with prior aortic surgery. The diagnosis of aorto-pulmonary fistula is difficult and many diagnostic tools must be utilized, in conjunction with a high clinical suspicion, to establish the diagnosis and thus enable timely surgical treatment. With early diagnosis and prompt surgical repair, certain death can be prevented.