Clinical characteristics during admission
NOAF was found in 16 patients (14.6%) within this cohort which also includes one post cardiac surgical patient. Clinical characteristics between patients developed NOAF were further studied with comparison to the group of patients without AF. Majority (70 [64%]) had acute kidney injury and of which 36% patients required renal replacement therapy. Major laboratory markers were traced during course of illness and cardiac troponin T was raised in 91% of the study group above the 99th percentile upper reference limit (URL). Nevertheless, median Left ventricular systolic function on echocardiography was within normal range (60%; IQR 55-65) (Table 2). Echocardiography was performed based on clinical grounds in patients (83%) with suspected acute cardiac injury evidenced by serial troponin rise, electrocardiographic changes, arrhythmia or haemodynamic instability/shock. Deterioration in left ventricular systolic function from baseline was observed only in three patients of which two admitted following acute myocardial infarction (AMI) and one developed AMI during COVID-19 illness due to an acute thrombus evident on coronary angiogram.
12% of our study population required ECMO for severe respiratory failure. Locally adopted guidelines were followed for management of venous thromboprophylaxis in COVID-19 and a modified anticoagulation regime with increased dose was advocated for patients with D-Dimer more than 3mg/L (normal range 0-0.5 mg/L). However a small proportion of our study group (7 patients; 6%) received therapeutic dose of anticoagulation assessed by their thrombosis risk especially when the D-Dimer levels were extremely high (>80 mg/L). 65 % of patients had D-Dimer levels 10 fold above the upper limits of normal (median 17 mg/L; IQR 6-59). Venous and arterial thromboembolism was one of the commonly observed complications [24 patients (22%)] with 76% diagnosed with pulmonary embolism on CTPA. 7 patients (44%) received therapeutic anticoagulation amongst NOAF group for AF, venous and arterial embolism and unusually elevated level of d-dimer.
One-third of patients (33%) did not survive the illness and the median time from admission to ICU discharge was 35 days (IQR 22-42) (Table 2).