Stanford Type A Aortic Dissection in COVID-19 Patient — Do the Risks of Surgery Outweigh the Benefits?

Abstract

Stanford Type A aortic dissections are a surgical emergency. When a patient with an acute ascending aortic dissection preoperatively tests positive for COVID-19, operative planning becomes more complex. We present a case of a 76-year-old female with a history of hypertension, hyperlipidemia, COPD, and known COVID- exposure who presented to outside hospital with dyspnea and equivocal chest pain. The patient was found to have a Stanford Type A/DeBakey Type II aortic dissection and transferred to our institution for management. After learning of her positive COVID-19 test, we elected to continue with surgical repair due to the high mortality associated with the disease. The procedure was successful and she recovered well postoperatively. In conclusion, a careful risk-benefit analysis must be performed when deciding operative management of a COVID-positive patient. We believe that surgical repair of a Type A aortic dissection in a COVID-positive patient should and can be safely performed.

Introduction

As of August 20th 2020, there have been over 5 million reported cases of and 170,000 deaths from the COVID-19 pandemic.¹ An early study conducted in New York, the first American epicenter of the outbreak, found a significant decline in the number of surgical cases due to acute type A aortic dissection as compared to the prior year.² This trend is widely thought to be secondary to public avoidance of health care facilities in an effort to limit possible COVID-19 exposure. However, type A aortic dissections remain an operative emergency and should be treated as such, even in the setting of a COVID-positive patient. Therefore, we present a case of a COVID-positive patient transferred to our institution for operative management of a Stanford type A aortic dissection.

Case Report

A 76-year-old female with a history of poorly controlled hypertension, hyperlipidemia, COPD and current tobacco use of 20 pack-years presented to our hospital as an emergency transfer for operative management of aortic dissection. She presented at outside hospital (OSH) with dyspnea and an equivocal history of chest pain after known COVID-19 exposure. Computed tomography (CT) was performed due to clinical suspicion of pulmonary embolism, and this revealed a Stanford Type A/ DeBakey Type II aortic dissection (Figure 1). The patient was transferred to our hospital, directly to the operating room. She was awake and alert on arrival. During surgical evaluation, our team received a call that the patient had tested positive for COVID-19 at OSH. This brought about the question of whether or not to intervene with shared decision-making between the patient and surgical team. Because of the emergent nature and high mortality of the disease process, we elected to proceed with operation. The heart was exposed via median sternotomy per usual. The ascending aorta and proximal aortic arch were dilated, with grossly normal coronary anatomy. Intraoperative transesophageal echocardiography (TEE) demonstrated left ventricular ejection fraction (LVEF) > 55% without significant valvular abnormalities. Aortic repair was performed under deep hypothermic circulatory arrest (DHCA) using a 24x8 mm Gelweave graft (Terumo Aortic). A large dissection flap was noted on the anterolateral surface of the ascending aorta (Figure 2). Also, chronic thrombotic formation was noted above the non-coronary sinus just above the sinotubular junction. The diseased segment and thrombus were removed. The times for cardiopulmonary bypass, aortic cross clamp, and DHCA were 71, 46 and 13 minutes, respectively. Post- procedure TEE demonstrated LVEF > 55% with no significant valvular abnormalities. The patient tolerated the procedure well and was transported to the intensive care unit (ICU).

The patient was extubated on post-operative day (POD) 0. No further COVID-19 testing was performed at our institution. She remained hemodynamically stable for her hospital stay. Given her COVID-19 infection and history of COPD, she was treated with a 10-day course of Dexamethasone. Chest tube and pacemaker wires were discontinued on POD4. She was discharged on POD5 in good condition.

Discussion

Stanford type A aortic dissection remains a highly lethal pathology with mortality historically described as 1-3% per hour in the first 48 hours.³ Recent guidelines in light of the COVID-19 pandemic define an ascending aortic dissection as an emergency which should be treated as such.⁴ However, several considerations must be made when the patient is COVID-positive. These include the presence of subclinical or clinical pulmonary manifestations, increased operative risk, personal protective equipment availability, and risk of exposure. Further, reports continue to emerge regarding the broad cardiac manifestations of COVID-19 which range from heart failure and cardiogenic and vasoplegic shock to myocarditis and coronary disease.⁵

Therefore, the choice to proceed with operative management is difficult – it requires shared decision making and a careful analysis of patient comorbidities and of the surgical risks versus potential benefits. If surgery poses less risk than the natural history of the disease process, the team should elect to proceed with definitive operative management. In our opinion, there are seldom any situations in which case a COVID-related illness would warrant the delay of surgical intervention for acute ascending aortic dissection.

While safety and infection control are the principal concern during aerosolizing procedures such as tracheal intubation in COVID-19 patients, cardiovascular manifestations of the disease require consideration during surgical planning. A broad range of cardiac manifestations can result from COVID-19 infection. These may be caused by an excessive inflammatory response which leads to hypercoagulation, the release of proinflammatory cytokines and direct virus- mediated myocardial injury.^6-7 Anesthesia itself may induce an inflammatory response in surgical patients, and this response is exaggerated in cardiac surgery which necessitates cardiopulmonary bypass.⁶ Further, because COVID-19 can cause severe and sudden cardiopulmonary collapse, the team must be prepared to engage in ECMO services when appropriate.⁸

There have been few case reports detailing operative management of type A aortic dissections in COVID-positive patients.^9-12 An early case was described in which a patient underwent successful aortic repair but was found to have worsening respiratory status in the ICU and subsequently diagnosed with COVID-19; this patient passed away within one week of positive testing.⁶ Other reports have described successful management in acute ascending aortic dissections, though these patients did not necessarily have positive testing prior to procedure. Our case describes a successfully managed cardiovascular surgical emergency in a known COVID-19 patient without major morbidity and mortality. Further, no one exposed from this case/patient has developed symptoms.

Therefore, we conclude that surgical repair of a type A aortic dissection in a COVID-positive patient can be safe and should be performed in certain instances emergently due to the high mortality associated with non-operative treatment.