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The relationship between severe acute respiratory syndrome coronavirus 2
(SARS-CoV-2/COVID-19) infection and cardiovascular disease is complex.
SARS-CoV-2 has cardiovascular sequelae and patients with established
cardiovascular disease are at risk of higher rates of infective
morbidity and mortality.1 In an attempt to preserve
scarce healthcare resources for COVID-19 patients, several international
healthcare systems adopted a strategy of deferring non-emergent cardiac
surgeries during the pandemic, and particularly during times of higher
case burdens.2, 3 Specific recommendations advising
against performing non-emergent cardiac operations amongst patients with
acute viral infections have also been made.2 As a
result, an international survey of global cardiac surgical centres in
2020 showed a median reduction in case volume of 50-75%, with 5% of
centres cancelling even emergency cases.4 Missing from
current available data to help inform policy development and
implementation, however, has been a robust understanding of the exact
impact of SARS-CoV-2 infection on cardiac surgical outcomes.
Bonalumi and colleagues probed rates of in-hospital mortality amongst
adult cardiac surgical patients at 22 Italian centres from February to
May of 2020.5 Of the 1354 patients analyzed, a total
of 48 (3.5%) were documented to be positive for COVID-19 in the
perioperative period. Unsurprisingly, the authors identified a
significantly higher in-hospital mortality amongst COVID-19 positive
patients compared to their COVID-negative counterparts (20.8% vs.
0.9%, p<0.001). Importantly, despite a trend towards higher
rates of emergent surgery amongst the COVID-19 positive group (6.3% vs.
0.3%, p=0.11), an independent association of COVID-19 infection and
in-hospital mortality was maintained in multivariable analysis. The
authors also identified low oxygen saturation and increasing age as
independent risk factors for in-hospital mortality within the COVID-19
positive subgroup. Finally, the authors reported an inpatient COVID-19
positivity rate almost 10 times higher than that of the general
population of Italy at the time. Given that 77% of these positive tests
were uncovered postoperatively, this raises the possibility that either
preoperatively infected patients were tested before becoming
PCR-positive, or that healthcare facilities acted a vehicle for
transmission. The results presented by Bonalumi and colleagues are
similar to those reported in other surgical services amongst COVID-19
patients in Italy6, as well as analyses of cardiac
surgical patients with COVID-19 at other centres.7-9The summation of the available evidence points towards the serious
consideration clinicians must give to deferring non-emergent cardiac
surgery of COVID-19 patients, particularly amongst those with advanced
age or sub-optimal pulmonary function.
While necessary for achieving both the broader public health priorities
and protecting patients with operable cardiovascular disease, it is
important to recognize that decisions to defer cardiac surgery may have
unintended negative consequences. Literature published prior to the
SARS-CoV-2 pandemic demonstrated that mortality rates may increase by
11% every month amongst patients waiting for coronary artery bypass
grafting.10 This figure becomes far more salient when
it is understood that a potential range of 1-8 months may be required to
clear the cardiac surgical backlog created by the COVID-19
pandemic.11
Clinicians today must choose between expending valuable healthcare
resources, as well as exposing patients to potential SARS-CoV-2
infection, or allowing for an increasing burden of cardiovascular
disease to continue to afflict already high-risk patients. A number of
solutions have been offered to address this, including the development
of clinical models to aid in triaging the patients most likely to suffer
adverse events while on the cardiac surgery
waitlist,12 as well as the implementation of
meticulous public health measures including infection control and
isolation.13 Perhaps no solution has been more
promising, however, than COVID-19 vaccination. A recent analysis of over
10,000 surgical patients demonstrated a significant reduction in
postoperative COVID-19 infections, as well as pulmonary and thrombotic
complications, amongst those vaccinated against COVID-19 compared with
those unvaccinated.14
In summary, Bonalumi and colleagues have provided further evidence that
confirms the significant additional risk perioperative COVID-19
infection confers to patients undergoing cardiac surgery. While
balancing the risk of COVID-19 infection with the risk of deferring
major cardiovascular surgery remains a dilemma for surgeons
internationally, emerging evidence suggests that the solution may lie in
continuing advocacy and education surrounding COVID-19 vaccination.