Soon after he repurposed his 60-bed cardiac unit to accommodate covid-19 patients, Mount Sinai cardiovascular surgeon John Puskas was stumped: With nearly all the beds now occupied by victims of the novel coronavirus, where had all the heart patients gone? Even those left almost speechless by crushing chest pain weren’t coming through the ER.

Variations on that question have puzzled clinicians not only in New York, the epicenter of the coronavirus outbreak, but across the country and in Spain, the United Kingdom and China. Five weeks into a nationwide coronavirus lockdown, many doctors believe the pandemic has produced a silent sub-epidemic of people who need care at hospitals but dare not come in. They include people with inflamed appendixes, infected gall bladders and bowel obstructions, and more ominously, chest pains and stroke symptoms, according to these physicians and early research.

“Everybody is frightened to come to the ER,” Puskas said.

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Some doctors worry that illness and mortality from unaddressed health issues may rival the carnage produced by the virus in regions less affected by covid-19. And some expect they will soon see patients who have dangerously delayed seeking care as ongoing symptoms force them to overcome their fear.

Evert Eriksson, trauma medical director at the Medical University of South Carolina, described a man in his 20s who tried to ignore the growing pain in his belly, toughing it out at home with the aid of over-the-counter painkillers. By the time he showed up at the hospital, perhaps 10 days after he should have, he had developed a large abscess, one that was gnawing through the muscle in his abdominal wall.

A fairly routine surgery and a night in the hospital had become a lengthy and difficult inpatient stay, with doctors operating and using antibiotics to control the widespread infection, according to Eriksson. Only after they succeed in vanquishing the infection can they address the appendix itself.

“That’s going to be a real wound-care challenge for him moving forward,” said Eriksson, who is caring for the patient. “He said to me he could [imagine] the virus crawling on the hospital. He was just scared to come.”

At MUSC, Eriksson’s general surgery floor, which has 20 beds, housed as few as three people for two to three weeks, he said. Now the census is back over 20.

“What we’re seeing is late presentation,” he said. “I would say 70 percent of the appendicitis on my service right now are late presentations. What happens when you present late with appendicitis is we can’t operate on you safely.”

Yet the 700-bed hospital in Charleston is only about 60 percent full, because like most facilities, MUSC discharged everyone it could to make room for the expected coronavirus surge. So far that hasn’t materialized. The hospital has not had more than 10 covid-19 patients admitted at any time, he said.

“We have five covid patients in the hospital right now, and we have five appendicitis cases” with complications from waiting too long to come in for care, Eriksson said.

Much of the reporting about missing patients is anecdotal — in medical chat rooms and on doctors’ social media accounts. Doctors say it’s unlikely there has been a decline in most of these conditions, which suggests that at least a few people may be dying at home, although there is no data yet to corroborate that.

In the case of severe heart attacks, the evidence is mounting that a large percentage of patients with symptoms that typically prompt urgent interventions are simply not showing up.

A report to be published in the Journal of the American College of Cardiology on nine high-volume cardiac catheterization labs across the country found a 38 percent drop in patients being treated for a life-threatening event known as a STEMI — the blockage of one of the major arteries that supplies oxygen-rich blood to the heart. The study compared what happened this past March, when covid-19 cases were climbing, with the treatments delivered from Jan. 1, 2019, through February 2020.

Those results — from hospitals across the country — are counterintuitive, physicians say. The stress caused by the pandemic would lead them to anticipate an increase in heart attacks. Covid-19 is also an inflammatory disease that can damage the heart muscle.

“We should have higher incidences of these events, but we are seeing dramatically fewer in the hospital system,” Puskas said. “That has to mean they are at home or in the morgue.”

A Gallup online poll taken March 28 to April 2 asked people with different conditions how concerned they would be about exposure to coronavirus if they needed “medical treatment right now” at a hospital or doctor’s office. Eighty-six percent of people with heart disease said they would be either “very concerned” or “moderately concerned.” Among people with high blood pressure, the figure was 83 percent.

With elective surgeries on hold, many hospitals such as Brigham and Women’s in Boston have found themselves trading treatment of traditional heart attacks for the complex assaults the novel coronavirus is making on the organ and the body’s ability to clot blood.

“People with smaller heart attacks, they may say, ‘Well I hope this is just indigestion.’ ” said, Gregory Piazza, one of the hospital’s cardiovascular specialists.

At MUSC, another doctor worried that mild stroke patients are enduring symptoms such as numbness, loss of sensation or weakness on one side of their body at home. Symptoms of small strokes can be transient, but they also can be warnings of larger strokes to come.

MUSC, a major stroke center, averaged 550 calls per month over the past four months about possible stroke patients from the 45 to 50 emergency rooms that refer patients. But it has seen just 100 in the first half of April, said Alex Spiotta, director of neurovascular surgery. Phone calls from patients to MUSC’s telestroke program dropped from as many as 20 daily to about nine in mid-April.

“That’s literally patients and their families who fear that it’s dangerous” to go to the hospital, he said. “We are worried that there might be a higher death toll from neglect of other diseases” than from covid-19.

At the University of Miami-Jackson Memorial Comprehensive Stroke Center, the March census of stroke patients is down almost 30 percent from February’s, said Ralph Sacco, chairman of neurology and former president of the American Academy of Neurology.

“What we would surmise is that more mild to moderate cases are not calling 911, or are afraid to come into the hospitals,” Sacco said.

The hospitals are beginning to reach out to the public through social media and public service announcements to ease fears about hospital safety.

“We’ve changed what we do,” to keep patients safe from the virus, Sacco said. “But we’re still able to care for people.”

The possibility that patients may be suffering — and even dying — at home rather than going to the hospital led the American College of Cardiology to launch a “Cardiosmart” campaign last week, attempting to reassure a wary population and encourage those with symptoms to call 911 for urgent care and to continue routine appointments, when practical through telemedicine: “Hospitals have safety measures to protect you from infection,” it reads.

“The emphasis here is safety,” said Harlan Krumholz, a cardiologist and health care researcher at Yale University and Yale New Haven Hospital, who advised on the campaign. “We want to make sure preventable deaths aren’t happening.”

There is no pill, no action, no behavior, he said, that could account for the almost 40 percent drop in STEMI patients. “We don’t have a means to cut your risk in half,” he said. “Not even primary angioplasty or stopping smoking.”

Still the shift has many doctors looking for other explanations, including the massive behavioral overhaul caused by the lockdown.

MUSC has seen a steep drop in trauma from car accidents, for example, because fewer people are driving, but no reduction in domestic violence or assaults among people who don’t live together, Eriksson said.

Many people who suffer from exertional angina are now sitting at home rather than climbing the subway stairs every day, and the threshold of discomfort that would drive them to seek care is likely far higher.

Joseph Puma, an interventional cardiologist at Mount Sinai, believes multiple changes created by the lockdown may be playing a role, including a decrease in air pollution and fewer high-fat restaurant meals after work.

“The plaques in arteries have not gone away,” he said. “You can argue that forced behavioral modifications may have taken away the triggers” that release them into the bloodstream.

And these days, some people who suffer cardiac arrests never make it to the hospital in New York, where EMTs and paramedics transport patients only if their pulse returns after CPR or defibrillation.

Puskas, the Mount Sinai cardiovascular surgeon, whose unit is now occupied entirely by covid-19 patients, suspects a few of the heart patients may not be missing but right there among the most seriously ill people in his new unit.

The virus strikes most harshly among people suffering from diabetes, obesity and high blood pressure — the very same conditions that predispose people to strokes and heart attacks and that are most prevalent among blacks and Hispanics.

“Some of them may be under our noses,” he said.

The role those factors may be playing will emerge over time from studies and shoe-leather epidemiology. But for now, Krumholz said, the key is to make sure people with symptoms overcome their fears and get prompt treatment that may save their lives or avoid long-term complications.

“Don’t delay,” he said.

Scott Clement and Emily Guskin contributed to this report.

Leonard.Bernstein@washpost.com

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