Case Reports We included four cases in this series. All were evaluated between March and April 2020 at the “Dr. Jose Eleuterio Gonzalez”, University Hospital in Monterrey, Mexico. Here, subjects with a suspicion of infection were evaluated by an infectiologist and those deemed at risk were tested using a real-time reverse transcription-polymerase chain reaction (RT-PCR). Subjects with positive results were then admitted to a special ward designated for management of these subjects. To ensure subjects’ safety, we followed the Ethical Guidelines of the 1975 Declaration of Helsinki and obtained verbal consent from patients’ next of kin. The cases were classified as severe (n = 1) or critical (n = 3) [10]. A certified echocardiographer performed the TTEs wearing personal protective equipment (PPE) and using the current American Society of Echocardiography (ASE) guidelines for image acquisition and interpretation. We also used the current ASE guidelines to obtain normal reference values [11, 12]. Case 1 A 76-year-old man presented to the emergency room (ER) with a 10-day history of shortness of breath, fever and dry cough. He had a previous diagnosis of prostate cancer, currently in remittance. His baseline characteristics are shown in Table 1. He had leukopenia, elevated cardiac markers including creatine kinase (CK), creatine kinase myocardial band (CK-MB) and lactate dehydrogenase (LDH) and a severe acute respiratory distress syndrome (ARDS) with a PaO2/FiO2 ratio of 59, which was initially treated with a high-flow nasal cannula (HFNC) and supportive treatment. A TTE was performed during day 8 of his hospital stay. This revealed abnormal LV function with an LVEF of 35% and a GLS of -14%. Echocardiographic characteristics are shown in Table 2. He was intubated the next day and developed barotrauma with a right pneumothorax that required a pleural catheter for evacuation. Afterward, on his 10th day, he developed an acute kidney injury (AKI) with anuria, multiorgan failure and acidosis. He passed away on his 11th day. Table 1 Baseline Clinical and Laboratory Characteristics Variable Case 1 Case 2 Case 3 Case 4 Gender Male Male Male Male Age (years) 76 64 66 26 Comorbidities Prostate cancer HIV None None White blood cell count, /µL 11.2 8.6 14.3 8.1 Lymphocytes, /µL 0.306 0.483 0.563 1.4 Serum creatinine, mg/dL 0.9 0.9 5.3 0.8 Aminotransferase   Aspartate, U/L 44 96 99 68   Alanine, U/L 40 108 43 85   Albumin, g/dL 2.1 2 2.7 3.4   hs-CRP, mg/dL 27 20.6 23.1 11.3   ARDS Yes Yes Yes Yes   PaO2/FiO2 ratio 59 66 180 258 Cardiac injury markers   hs-TpnI, ng/L 2.8 5.4 5.6 1.4   CK, U/L 721 868 517 50   CK-MB, U/L 29 35.3 26.5 n/a   LDH, U/L 312 259 424 317 hs-CRP: high-sensitivity C-reactive protein; ARDS: acute respiratory distress syndrome; hs-TpnI: high-sensitivity troponin I; CK: creatine kinase; CK-MB: creatine kinase myocardial band; LDH: lactate dehydrogenase. Table 2 Echocardiographic characteristics and Recommended Reference Values Variable Case 1 Case 2 Case 3 Case 4 Reference value LV septal thickness, cm 0.8 1.2 1.1 0.7 0.6 - 1 Posterior wall thickness, cm 0.8 1.1 0.8 0.9 0.6 - 1 LV indexed mass, g/m2 80.7 56.5 81.4 73.6 49 - 115 Relative wall thickness 0.31 0.47 0.32 0.37 0.24 - 0.42 VfdVI MOD BP 38 76 n/a 83 62 - 150 VfsVI MOD BP 25 26 n/a 56 21 - 61 LVEF, % 35 66 65 33 52 - 72 Left atrial indexed volume, mL/m2 21.8 15.4 11.1 < 34 Average GLS, % -14 -18 n/a -14 < -18.5% Aplax GLS, % -12 -18 n/a -14 < -18.5% a4C GLS, % -13 -18 n/a -13 < -18.5% a2C GLS, % -15 -19 n/a -14 < -18.5% TAPSE, mm 25 26 20 20 > 18 S wave, cm/s 0.18 0.7 0.18 0.12 > 0.095 RV basal diameter, mm 33 34 47 39 25 - 41 RV mid-cavity diameter, mm 29 22 45 34 19 - 35 MV E wave velocity, m/s 0.5 0.83 0.54 0.38 > 50 MV deceleration time, ms 210 218 185 147 > 200 E/A ratio 0.63 1.03 0.69 0.44 ≥ 0.8 Septal e′ velocity, m/s 0.05 0.08 0.07 0.1 > 7 Lateral e′ velocity, m/s 0.1 0.09 0.1 0.1 > 10 E/e′ ratio 6.6 9.66 6.27 3.78 < 10 Data are shown as frequencies (%) and median (min. - max.) or mean ± SD. LV: left ventricular; LVEF: LV ejection fraction; GLS: global longitudinal strain; a4C: apical four-chamber view; APLAX: apical long axis view; a2C: apical two-chamber view; TAPSE: tricuspid annulus plane systolic excursion; RV: right ventricular; MV: mitral valve; n/a: not available. Case 2 A 64-year-old man who was human immunodeficiency virus (HIV)-positive presented to the ER with a 4-day history of headache and malaise. On interrogation, he referred traveling to the United States during the previous 2 weeks. Baseline characteristics are shown in Table 1. On admittance, he had a temperature of 38.3 °C. On his seventh day of hospital stay, he developed respiratory insufficiency and was intubated. Septic shock was diagnosed on the eighth day and vasopressor support was initiated. A TTE was done to evaluate shock etiology, which showed an abnormal ventricular geometry with concentric remodeling and a GLS of -18% with an LVEF of 66% (Table 2). During his time in the ICU, on day 14, the subject developed new infiltrates on his chest X-ray, so a diagnosis of ventilator-associated pneumonia was entertained, and broad-spectrum antibiotics were started. This was eventually found to be caused by Klebsiella spp, according to an endotracheal aspiration culture. On his 21st day, he presented massive hemoptysis and expired. Case 3 A 66-year-old man presented with a 5-day history of shortness of breath, fever and dry cough. His previous medical history was unremarkable. He reported having a family member that had traveled to the United States during the previous month. He presented to the ER with respiratory insufficiency syndrome. During his first day in the ICU, he was classified as a moderate ARDS with a PaO2/FiO2 ratio of 180 (Table 1). He was initially managed with HFNC and, due to an altered mental state, was then intubated using video laryngoscopy. On his third day, he developed an AKI with anuria and septic shock that was treated with vasopressors. On his fourth day, prolonged intermittent renal replacement therapy was started using a non-tunneled dialysis catheter. A TTE was done on his eighth day, showing an LVEF of 65% (Table 2), a mobile vegetation with a size of 12 × 10 mm that was attached to the septal leaflet of the tricuspid valve, and severe tricuspid regurgitation (Fig. 1a). Four consecutive blood cultures were performed and all were negative. No other of Duke’s criteria for infectious endocarditis were present. On his 14th day in the ICU, fever was again identified, accompanied by a new infiltrate on his chest X-ray. A diagnosis of ventilator-associated pneumonia was established and broad-spectrum antibiotics were started. At this time, a new RT-PCR for SARS-CoV-2 was performed, which was still positive. During his 22nd day in the ICU, the patient was still intubated, dependent of renal replacement therapy (RRT) and vasopressor support, with altered mentation (unarousable) during his unsuccessful ventilation weaning trials. He was being considered for an electroencephalogram to evaluate his mental status and a tracheostomy because of his prolonged intubation. Figure 1 (a) Modified a4c view showing the tricuspid vegetation of case 3. (b) Peak GLS showing decreased values in the inferolateral and inferoseptal territories of case 4. a4C: apical four-chamber view; GLS: global longitudinal strain. Case 4 A 26-year-old man presented to our institution with a 5-day history of malaise, fever, arthralgias, myalgias and shortness of breath. His medical background was unremarkable. On arrival, he had tachypnea and a temperature of 39.6 °C. On his second day, he required supplementary oxygen through a standard nasal cannula. His laboratory results showed hypoalbuminemia and elevated LDH (Table 1). On his third day, a TTE was performed, which showed abnormal regional function with hypokinetic segments in the basal and medial inferior and inferolateral territories, an LVEF of 33% and a GLS of -14% (Table 2). We present the GLS pattern of this patient in Figure 1b. This subject was managed with supportive treatment and supplementary oxygen, which has finally removed during his ninth day in the hospital. He was discharged on day 13.