A new normal
The pandemic affects our daily routine as cardiac surgeons in multiple
ways: limited intensive care unit (ICU) beds and ventilators, necessity
to postpone elective and/or complex cardiac surgeries, shortage of
healthcare workers, sickness of healthcare staff and/or risk of
infection of our Teams, risk of developing COVID-19 after cardiac
surgery, and patients with COVID-19 needing urgent cardiac operations
without having a properly organized operating room and ICU. The pandemic
has hit every health system and the first bailout strategy was to
maximize available ICU resources by discontinuing elective surgical
activity. As Cardiac Surgeons, treating potentially life-threatening
conditions on a daily basis, we seek direction from the National Cardiac
Surgery Societies: nothing has been clearly stated about the triage
process in severe valvular diseases. We believe that a comprehensive
reorganization of our activities should be considered. Indeed, the
system should aim to keep as much as ICU resources available for
COVID-19 patients and at the same time, segregate the positive COVID-19
cases.
Should we consider a “regional” reorganization as well as a“hospital” reorganization? For example, consider the “hub
center” system established in Lombardy (Italy) in the beginning of
March by the Regional Government. They identified 18 hub Centers that
would address the urgent and emergent pathologies, leaving the other
hospitals available for COVID-19 patients. This setting may have some
drawback: Hospital chains may be able to reorganize and distribute
patients to specific centers, only if both expenses and profits can be
equally shared. Moreover, this may not be sustainable with individual
stand alone institutions. As far as “hospital” reorganization, every
Institution has been allowed to determine the proper pathway upon which
to open their operating schedules as long as the procedure is not
deferrable for more than 1 month.
We are heading to a new normal , working through the SARS-CoV-2
era, adjusting our daily practices with various safety measures. This
also means being ready to face future waves of the pandemic and to
working amongst a population with a small but still present portion of
positives. We have to be prepared to preserve the safety of health care
workers and hospital admitted patients, while having dedicated OR, ICU
and ward beds to treat COVID-19 patients: indeed, the access to a proper
and timely treatment cannot depend on the outcome of a swab.
To reach those goals, it is necessary to screen and segregate the
positives with dedicated pathways for further diagnostic testing and
treatment, regardless of the admitting diagnosis. A committed health
care team would be ideal: chosen among the immunes (if this coronavirus
generates a consistent and persistent immune response) or among those
with less risk factors to develop a severe COVID-19. To stress this
idea, the foundation of a SARS-CoV-2 Hub Center seems to be an option to
eradicate the risk of in-hospital infection in non-COVID-19 patients,
who are the most at risk. Regarding pathologies that merit priority for
urgent treatment, it’s reasonable to focus on those valvular diseases
that directly may have an associated degree of pulmonary hypertension
(PH). PH associated with left heart disease (Nice group 2) is by far the
most common cause of PH and accounts for 50–85% of the cases.
Left-sided valvular heart disease can cause an elevation of the left
atrial pressure which usually leads to post-capillary PH, which is
passively transmitted backward toward the pulmonary venous system. Based
on the pathological findings and on the suspected mechanism of lung
damage, an increased pressure in the pulmonary artery may further
compromise the effective oxygen/carbon dioxide exchange in the alveoli.
Then, severe mitral regurgitation (MR), severe mitral stenosis (MS) and
severe aortic stenosis (AS) are the main pathologies to focus upon. In
severe primary MR about 20-30% of patients have systolic pulmonary
artery pressure (sPAPS) >50 mmHg; secondary MR sees an
slightly higher prevalence of severe PH(12). Approximately 65% of
patients with symptomatic severe AS develop some degree of PHT, with the
prevalence increasing to 80% in octogenarians because of chronic
elevation of left ventricular end diastolic pressure; a more severe
degree of PHT is present in about 15% of AS patients. Rest
echocardiography is essential to assess the presence of pulmonary
hypertension in the symptomatic patient. On the other hand, in order to
correctly identify and stratify asymptomatic patients with a degree of
pulmonary hypertension, exercise echocardiography is crucial. The
prevalence of PH almost doubles under effort in patients with mitral
regurgitation and increases almost 10 fold in asymptomatic patients with
severe aortic stenosis(12).