Roger writes,
> .. Guesses might be that:
>
> (1) there are multiple models, and they paint quite different pictures
> (2) the model(s) deliver very different pictures ..
> (3) the model(s) deliver pictures that aren't consistent with what's
been portrayed to the public .. This is all really, really challenging.
And now, how about this?
One in five patients may have zero respiratory distress .. but die from heart
failure .. from the virus directly infecting the heart muscle.
“Mysterious Heart Damage Hitting COVID-19 Patients”
WebMD News from Kaiser Health News
By Markian Hawryluk
https://www.webmd.com/news/20200406/mysterious-heart-damage-not-just-lung-troubles-befalling-covid-19-patients
Monday, April 06, 2020 (Kaiser News) -- While the focus of the COVID-19
pandemic has been on respiratory problems and securing enough ventilators,
doctors on the front lines are grappling with a new medical mystery.
In addition to lung damage, many COVID-19 patients are also developing heart
problems — and dying of cardiac arrest.
s more data comes in from China and Italy, as well as Washington state and New
York, more cardiac experts are coming to believe the COVID-19 virus can infect
the heart muscle.
An initial study found cardiac damage in as many as 1 in 5 patients, leading to
heart failure and death even among those who show no signs of respiratory
distress.
That could change the way doctors and hospitals need to think about patients,
particularly in the early stages of illness.
It also could open up a second front in the battle against the COVID-19
pandemic, with a need for new precautions in people with preexisting heart
problems, new demands for equipment and, ultimately, new treatment plans for
damaged hearts among those who survive.
“It’s extremely important to answer the question: Is their heart being affected
by the virus and can we do something about it?” said Dr. Ulrich Jorde, the head
of heart failure, cardiac transplantation and mechanical circulatory support
for the Montefiore Health System in New York City.
“This may save many lives in the end.”
Virus Or Illness?
The question of whether the emerging heart problems are caused by the virus
itself or are a byproduct of the body’s reaction to it has become one of the
critical unknowns facing doctors as they race to understand the novel illness.
Determining how the virus affects the heart is difficult, in part, because
severe illness alone can influence heart health.
“Someone who’s dying from a bad pneumonia will ultimately die because the heart
stops,” said Dr. Robert Bonow, a professor of cardiology at the Northwestern
University Feinberg School of Medicine and editor of the medical journal JAMA
Cardiology. “You can’t get enough oxygen into your system and things go
haywire.”
But Bonow and many other cardiac specialists believe a COVID-19 infection could
lead to damage to the heart in four or five ways. Some patients, they say,
might be affected by more than one of those pathways at once.
Doctors have long known that any serious medical event, even something as
straightforward as hip surgery, can create enough stress to damage the heart.
Moreover, a condition like pneumonia can cause widespread inflammation in the
body. That, in turn, can lead to plaque in arteries becoming unstable, causing
heart attacks. Inflammation can also cause a condition known as myocarditis,
which can lead to the weakening of the heart muscle and, ultimately, heart
failure.
But Bonow said the damage observed in COVID-19 patients could be from the virus
directly infecting the heart muscle.
Initial research suggests the coronavirus attaches to certain receptors in the
lungs, and those same receptors are found in heart muscle as well.
Initial Data From China
In March, doctors from China published two studies that gave the first glimpse
at how prevalent cardiac problems were among patients with COVID-19 illness.
The larger of the two studies looked at 416 hospitalized patients. The
researchers found that 19% showed signs of heart damage. And those who did were
significantly more likely to die: 51% of those with heart damage died versus
4.5% who did not have it.
Patients who had heart disease before their coronavirus infections were much
more likely to show heart damage afterward. But some patients with no previous
heart disease also showed signs of cardiac damage. In fact, patients with no
preexisting heart conditions who incurred heart damage during their infection
were more likely to die than patients with previous heart disease but no
COVID-19-induced cardiac damage.
It’s unclear why some patients experience more cardiac effects than others.
Bonow said that could be due to a genetic predisposition or it could be because
they’re exposed to higher viral loads.
Those uncertainties underscore the need for closer monitoring of cardiac
markers in COVID-19 patients, Jorde said. If doctors in New York, Washington
state and other hot spots can start to tease out how the virus is affecting the
heart, they may be able to provide a risk score or other guidance to help
clinicians manage COVID-19 patients in other parts of the country.
“We have to assume, maybe, that the virus affects the heart directly,” Jorde
said. “But it’s essential to find out.”
Facing Obstacles
Gathering the data to do so amid the crisis, however, can be difficult.
Ideally, doctors would take biopsies of the heart to determine whether the
heart muscle is infected with the virus.
But COVID-19 patients are often so sick it’s difficult for them to undergo
invasive procedures. And more testing could expose additional health care
workers to the virus. Many hospitals aren’t using electrocardiograms on
patients in isolation to avoid bringing additional staff into the room and
using up limited masks or other protective equipment.
Still, Dr. Sahil Parikh, an interventional cardiologist at Columbia University
Irving Medical Center in New York City, said hospitals are making a concerted
effort to order the tests needed and to enter findings in medical records so
they can sort out what’s going on with the heart.
“We all recognize that because we’re at the leading edge, for better or for
worse, we need to try to compile information and use it to help advance the
field,” he said.
Indeed, despite the surge in patients, doctors continue to gather data, compile
trends and publish their findings in near real time. Parikh and several
colleagues recently penned a compilation of what’s known about cardiac
complications of COVID-19, making the article available online immediately and
adding new findings before the article comes out in print.
Cardiologists in New York, New Jersey and Connecticut are sharing the latest
COVID-19 information through a WhatsApp group that has at least 150 members.
And even as New York hospitals are operating under crisis conditions, doctors
are testing new drugs and treatments in clinical trials to ensure that what
they have learned about the coronavirus can be shared elsewhere with scientific
validity.
That work has already resulted in changes in the way hospitals deal with the
cardiac implications of COVID-19. Doctors have found that the infection can
mimic a heart attack. They have taken patients to the cardiac catheterization
lab to clear a suspected blockage, only to find the patient wasn’t really
experiencing a heart attack but had COVID-19.
For years, hospitals have rushed suspected heart attack patients directly to
the catheterization lab, bypassing the emergency room, in an effort to shorten
the time from when the patient enters the door to when doctors can clear the
blockage with a balloon. Door-to-balloon time had become an important measure
of how well hospitals treat heart attacks.
“We’re taking a step back from that now and thinking about having patients
brought to the emergency department so they can get evaluated briefly, so that
we could determine: Is this somebody who’s really at high risk for COVID-19?”
Parikh said. “And is this manifestation that we’re calling a heart attack
really a heart attack?”
New protocols now include bringing in a cardiologist and getting an EKG or an
ultrasound to confirm a blockage.
“We’re doing that in large measure to protect the patient from what would be an
otherwise unnecessary procedure,” Parikh said, “But also to help us decide
which sort of level of personal protective equipment we would employ in the
cath lab.”
Sorting out how the virus affects the heart should help doctors determine which
therapies to pursue to keep patients alive.
Jorde said that after COVID-19 patients recover, they could have long-term
effects from such heart damage. But, he said, treatments exist for various
forms of heart damage that should be effective once the viral infection has
cleared.
Still, that could require another wave of widespread health care demands after
the pandemic has calmed.
--
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