Discussion
We present a case of a successful CABG surgery in a patient with
asymptomatic SARS-CoV-2 infection presenting with acute coronary
syndrome and with multi-vessel severe CAD requiring urgent surgery. We
thoroughly evaluated the patient to identify active COVID-19 infection
by assessing for common inflammatory markers and CT findings associated
with COVID-19. After confirming the absence of subclinical COVID-19, we
proceeded with the CABG operation with a favorable outcome and without
post-operative COVID-19 manifestations.
To the best of our knowledge, there are no published reports of CABG
operation in patients with pre-operatively confirmed SARS-CoV-2
infection. In a report of post-operatively diagnosed COVID-19 after CABG
for an acute coronary syndrome, the patient succumbed to severe
pneumonia.1 In accordance with the United Kingdom
National Health Service recommendations, the patient was not initially
tested for the SARS-CoV-2 at presentation (15 days prior to surgery) as
he did not have COVID-19 symptoms and had normal inflammatory
markers.1 A chest CT scan at presentation showed mild
chronic obstructive pulmonary disease. The patient developed pneumonia
on postoperative day 1 with severe hypoxia and fever. Chest radiography
showed bilateral consolidation and bronchial-alveolar lavage was
positive for SARS-CoV-2. The authors recognized that undiagnosed or
potentially concomitant COVID-19 infection might precipitate a
catastrophic pathologic response refractory to standard treatments after
cardiac surgery which might pose a challenge to
clinicians.1 In a case series if eleven patients with
COVID-19 infection diagnosed after lung cancer surgery, three patients
expired in the immediate post-operative period.3 In
two other reports of emergency thoracic surgery (embolectomy for
pulmonary embolism and acute type A aortic dissection repair) and
post-operatively diagnosed COVID-19 , the patients had a complicated
post-operative course and eventually died from multiorgan
dysfunction.2,4 A review of a pre-operative CT chest
in one of these patients showed signs consistent with COVID-19 lung
lesions.2
The key takeaway points from our case presentation are: 1) Routine
testing for the SARS-CoV-2 in all patients who require cardiac surgery
to identify asymptomatic/subclinical infection. 2) In asymptomatic
SARS-CoV-2 infection, assessing for subclinical active infection (with
inflammatory markers and CT chest) helps to identify patients at higher
risk of developing post-operative complications. This is especially
important for patients requiring cardiopulmonary bypass as subclinical
pneumonia can result in severe hypoxia and complicate weaning from
cardiopulmonary bypass. 3) Careful monitoring of all SARS-COV-2 positive
patients postoperatively for development of COVID-19. Nasal swab testing
with reverse transcriptase-polymerase chain reaction to detect the
SARS-CoV-2 RNA has only 70% sensitivity. Any clinical change to suggest
active COVID-19 in the pre- or post-operative period should prompt
repeat swab testing or chest CT imaging to improve risk stratification.
Chest CT screening has a higher sensitivity (98%) than nasal swab for
SARS-CoV-2 infection as CT findings occur earlier.5Post-intubation bronchoalveolar lavage can be considered.
As we move forward in this pandemic, we need to continue to provide
appropriate medical care for patients with asymptomatic or subclinical
SARS-COV-2 infection who require cardiac surgery. Careful screening
strategies, standard guideline recommendations and hospital level
protocols are required to identify higher risk patients who are at
greater risk of post-surgical morbidity and mortality.