ABC | Volume 115, Nº1, July 2020

Review Article Costa et al. Cardiovascular Imaging and Interventional Procedures Arq Bras Cardiol. 2020; 115(1):111-126 should be dedicated to patients with COVID-19, and it should remain in the contaminated areas. Additional protective measures can be adopted, such as plastic film wrapping of the device and/or interposition of an acrylic (or plastic) barrier between the examiner and the patient. Portable or pocket ultrasound devices can be easily covered, transported, and disinfected; however, their diagnostic resources are limited (point-of-care). Echocardiographic contrast agents might be useful, and their use should be anticipated to prevent additional circulation in the exam room. 26 It is worth noting that contrast agents should not be used for critical patients with circulatory instability and severe pulmonary impairment. 3.4.2. Focused (point-of-care) echocardiography: may be important for the care of critical patients during the COVID-19 pandemic. Although not equivalent to complete TTE, focused echocardiography can confirm or exclude a specific diagnosis, supporting therapeutic decisions. 27 It can be performed by properly trained physicians already providing direct care to the patient in the intensive care unit, thus contributing to reduce the exposure of the echocardiographer. Portable or pocket ultrasound devices should be preferably used to facilitate access to bed and further disinfection. 3.4.3. Transesophageal echocardiography: there is special concern regarding TEE, because of the high risk of equipment and healthcare personnel contamination with droplets and aerosols. Thus the incremental value of TEE over TTE should be carefully assessed, and TEE should be avoided in most cases. 16 Whenever possible, other alternatives should be considered, such as repeating TTE or using another imaging technique with less contact between examiner and patient, such as CT and CMRI. To perform urgent TEE in hospitalized patients, the examiner should use complete PPE for respiratory protection, in addition to protective cover for the transducer. 3.4.4. Stress echocardiography: exercise stress echocardiography can increase the risk of contamination via droplets and should, thus, be deferred (patients at low risk of COVID-19) or not performed (patients with suspected or confirmed COVID-19). When there is proper indication and deferral is not possible or recommended, pharmacological stress echocardiography should be preferred for patients at low risk of COVID-19 (patient with cancer waiting for surgery and with high pretest probability of obstructive CAD). In addition, during the pandemic, selected cases of chronic CAD could be investigated by use of CCTA. 3.4.5. Fetal echocardiography: proper indication for FE remains the same during the pandemic, which is pregnancy with high risk of fetal heart disease; 16 the exam should be performed outside the hospital setting. At the moment, there is no indication for routine FE in mothers with suspected or confirmed COVID-19. 3.4.6. Lung ultrasonography: is an agile tool to assess lung involvement and to follow up the result of bedside therapeutic interventions. The following findings have been reported in COVID-19: thickening and irregularity of the pleural line with loss of continuity; several patterns of B lines (focal, multifocal, confluent); and lung consolidations (frequently subpleural). 28 Although those abnormalities are unspecific and found in other types of pneumonia, they are valuable to track the evolution of COVID-19 pneumonia. Pleural effusions are not frequent, and A lines appear during the recovery phase. 4. X-ray, Computed Tomography and Cardiac Magnetic Resonance Imaging Pulmonary and cardiovascular imaging tests play an important role in the accurate diagnosis of COVID-19 complications. Chest X-ray is the most used exam, but CT might be necessary. 16 The CMRI might be required in patients with suspected myocarditis and/or Takotsubo syndrome. 16 However, before indicating CT and CMRI, some considerations should be made. Such tests pose a significant risk of contamination for patients and health professionals, not only those related to patient’s transportation but also to direct contamination during the exam. The CMRI and CT should only be performed if the information resulting from the tests could help the patient’s clinical management. Those exams should be indicated for stable patients with a minimum transportation risk, if performed at a safe environment, with strict adherence to local safety rules, and with the use of PPE by the professionals involved in patient’s transportation and image acquisition. 16 4.1. Chest X-ray Chest X-ray is usually the first imaging test performed in patients with COVID-19 because of its low cost and ease of access, mainly in hospitalized patients who cannot be safely transported. 29 Chest X-ray has low sensitivity. In addition, X-ray findings are not specific to COVID-19, because they can also be associated with the flu syndrome, such as consolidations (47%), low-density opacities (33%), and pleural effusion (3%). 30 The imaging findings are predominantly peripheral, occurring most often within 10 to 12 days. 30 Figure 1 summarizes the major chest X-ray findings. 4.2. Chest Computed Tomography Chest CT is a tool to support the diagnosis, while COVID-19 confirmation is based on viral reverse transcriptase polymerase chain reaction (RT-PCR) or serological tests. Performing screening CT for the identification of COVID-19 should not be encouraged. 29 Asymptomatic or mildly symptomatic patients should not undergo CT; however, for mildly symptomatic patients with access to neither RT-PCR nor serological tests, the benefit of performing CT is uncertain. For severely symptomatic, hospitalized patients, who can be transported safely, such as using a mask, CT should be considered when complications are suspected (pulmonary thromboembolism, pleural effusion, and superimposed bacterial infection). 29 Figure 1 summarizes CT findings and recommendations for performing CT. The protocol recommends the use of low radiation doses, preferably with no contrast medium administration, which should be reserved for specific indications, such as to discard pulmonary thromboembolism. 29 In the first days after symptom onset, CT can be normal, which does not exclude COVID-19. The CT sensitivity and specificity reported for COVID-19 vary widely (60% to 98%, and 25% to 53%, respectively), probably 114