Occult Cardiac Amyloidosis: A Rare Contributor of Postoperative Demise Following Cardiac Surgery
TA Flood, JP Veinot. The Ottawa Hospital, Ottawa, ON, Canada
Background: Cardiac amyloidosis is an uncommon disorder that occurs when fibrillar proteins are deposited in the myocardium and/or coronary artery walls and leads to abnormalities in contraction and conduction. Patients with cardiac amyloidosis can present with angina, symptoms of myocardial infarction, or sudden death. We present two patients who underwent cardiac surgery whose postoperative courses were complicated by poor cardiac output and eventual death. Autopsies showed previously undiagnosed severe cardiac amyloidosis.
Design: Patient#1: 52 year old man admitted for triple CABG following coronary in-stent restenosis. Postoperative course was complicated by low cardiac output requiring inotropes and an intra-aortic balloon pump. Further complications included atrial fibrillation, sepsis, and hepatic and renal insufficiency. On postoperative day 26 the patient suffered a fatal cardiac arrest. Patient#2: 86 year old man admitted for aortic valve replacement and CABG. His post-operative course was complicated by right ventricular failure, sinus ventricular tachycardia and left ventricular dysfunction for which he required prolonged inotropic support. He developed bilateral pleural effusions and a mediastinal soft tissue abscess. On postoperative day 32 the patient went into asystole and died.
Results: Patient#1: Heart weight was 575g and all coronary artery bypass grafts were intact and uncomplicated. There was extensive myocardial involvement by amyloid. Amyloid depostis were also observed within the walls of epicardial arterioles and in the vein grafts. Moderate deposition of amyloid was detected systemically. The amyloid was AL type and an underlying plasma cell dyscrasia was identified. Patient#2: Heart weight was 550g and the aortic valve prosthesis was uncomplicated. Coronary artery bypass grafts were intact and patent. There was moderate to severe amyloid involvement in the myocardium of all chambers. Amyloid also involved the visceral vessels (pulmonary arteries and veins) and was the senile type.
Conclusions: Occult cardiac amyloidosis is an infrequently described entity that can contribute significantly to postoperative morbidity and mortality. There are no specific clinical signs or symptoms that are associated with this disorder. Prior cardiac surgery can cloud the clinical picture because many of the observed signs and symptoms can be attributed to postoperative sequelae. These cases demonstrate a rare but potentially fatal condition that can be considered in postoperative cardiac surgery patients who are doing poorly.
Monday, March 22, 2010 9:30 AM
Poster Session I Stowell-Orbison/Surgical Pathology/Autopsy Awards Poster Session # 2, Monday Morning