ATRIAL FLUTTER WITH CARDIAC TAMPONADE AS THE INITIAL MANIFESTATION OF LUNG CANCER

TOPIC: Lung Cancer TYPE: Medical Student/Resident Case Reports INTRODUCTION: Metastases to the heart and pericardium are uncommon with an incidence of 11% [1]. Symptoms include dyspnea, palpitations, arrhythmias, lower-extremity edema, and chest pain. We present a rare case of metastatic adenocarcinoma of lung presenting as new-onset atrial flutter and cardiac tamponade. CASE PRESENTATION: A 70-year-old man with a history of COPD and tobacco abuse presented with worsening shortness of breath for 2 weeks. On exam, he had heart rate 173 beats/min, blood pressure 88/58 mmHg, and respiratory rate 40/min. He had decreased breath sounds and expiratory wheezes bilaterally. ECG showed atrial flutter with rapid ventricular rate and 2:1 block. He received intravenous digoxin and intravenous amiodarone bolus followed by infusion with failure of improvement of heart rate. He was placed on BiPAP for worsening respiratory distress and admitted to the cardiac care unit. CT chest showed diffuse bilateral ground-glass opacities with scattered areas of nodular consolidation and bilateral pleural effusions concerning for malignancy. Patient underwent transesophageal echocardiography (TEE)-guided cardioversion with 100 J with restoration to normal sinus rhythm. TEE revealed large pericardial effusion with cardiac tamponade. Pericardial window was done with rapid improvement of symptoms. Cytology from pericardial effusion revealed adenocarcinoma of lung origin. After 2 weeks, he was weaned to 3 L oxygen and discharged home with a plan to initiate cancer treatment. DISCUSSION: Lung cancer is the leading cause of cancer-related deaths in the United States accounting for 23% of all cancer deaths [2]. It is the most common cause of metastases to the heart and pericardium due to the proximity to the heart. Malignant pericardial effusion may occur due to occlusion of the cardiac lymphatic or venous drainage by tumor, overproduction of pericardial fluid by tumor, hypoalbuminemia from malignancy-associated cachexia, and complication of treatment including chemotherapy and radiation [3]. Cytologic analysis of pericardial fluid and pericardial biopsy can confirm the diagnosis. Rapid fluid accumulation in the pericardium can cause cardiac tamponade. Treatment options include emergent pericardiocentesis or pericardial window. Arrhythmias are a rare manifestation of malignant pericardial effusion with only one reported case of atrial flutter to our best knowledge [3]. The compression of the heart by the pericardial effusion creating a focus for macro-reentry likely explains the mechanism of action of atrial flutter in our case. CONCLUSIONS: Arrhythmias are a rare complication of malignant pericardial effusion which in the setting of tamponade can cause rapid hemodynamic instability. Clinicians should be alert to look for lung tumors invading the pericardium when a patient with significant cancer risk factors presents with new-onset atrial flutter. REFERENCE #1: Chiles C, Woodard PK, Gutierrez FR, Link KM. Metastatic involvement of the heart and pericardium: CT and MR imaging. Radiographics. 2001;21(2):439-449. REFERENCE #2: CDCBreastCancer. An update on cancer deaths in the United States. Cdc.gov. Published February 24, 2021. Accessed April 30, 2021. https://www.cdc.gov/cancer/dcpc/research/update-on-cancer-deaths/index.htm REFERENCE #3: Suwanwongse K, Shabarek N. Atrial flutter as an initial presentation of malignant pericardial effusion caused by lung cancer. Cureus. 2020;12(11):e11712. DISCLOSURES: No relevant relationships by jehann abdallah, source=Web Response No relevant relationships by jacky duong, source=Web Response No relevant relationships by Qasim Jehangir, source=Web Response No relevant relationships by Cormack Lazarus, source=Web Response No relevant relationships by Yi Lee, source=Web Response No relevant relationships by heather wynne, source=Web Response