Cardiac Arrests Have Soared Worldwide: How Was COVID-19 to Blame?

There are more reports from around the world documenting a stark rise in cardiac arrests occurring outside the hospital during the COVID-19 pandemic. Still unsettled, however, is how much the virus is to blame for triggering lethal arrhythmias, or whether they are mostly a tragic consequence of hospital avoidance and the so-called missing STEMIs.

Cardiologists around the globe who first warned of the precipitous drop in acute MI seen in the first few months of the pandemic also predicted an inevitable rise in the number of serious, late presentations of delayed care—an increase in cardiac arrest among them.

Swiftly thereafter, an Italian research team published a report on the spike in cardiac arrests in the Lombardy region. In that paper, Simone Savastano, MD (Fondazione IRCCS Policlinico San Matteo, Pavia, Italy), and colleagues identified a 58% increase in the number of out-of-hospital cardiac arrests (OHCAs) between February 20 and March 31, 2020, as compared with the same period last year.

Last week, Savastano’s group followed that up with another paper published in the European Heart Journal, that expanded their window of observation to April 20, and demonstrated a 52% increase in OHCA over this extended period. They further document a “strong and statistically significant correlation” between the cumulative incidence of OHCA per 100,000 residents of the region in 2020 and the cumulative incidence per 100,000 inhabitants of COVID-19 in the same four provinces.

Italy, France, and the United States

Since the Lombardy data were published, additional papers have emerged from other hot spots, including Paris, France, and New York City, showing the same dreaded spikes in OHCA.

Writing in the Lancet Public Health late last month, Eloi Marijon, MD, PhD (European Georges Pompidou Hospital, Paris), and colleagues describe the rise in OHCA during the peak pandemic period there: March 16 to April 26, 2020. Compared with the maximum weekly incidence of 13.42 per million for the same period averaged over the prior 8 years, the maximum weekly incidence during the pandemic period doubled to 26.64 per million. Mirroring what other reports are seeing, the patient demographics were similar in both groups, but patients during the pandemic were suffering more arrests at home, receiving less bystander CPR, facing longer delays to intervention, and experiencing a lower likelihood of survival to hospital admission.

Pamela Lai, MD (Office of Medical Affairs, Fire Department of the City of New York, Brooklyn), and colleagues report in JAMA Cardiology that the number of patients undergoing emergency medical service (EMS) resuscitation for OHCA during the height of the pandemic in New York was three times higher than during the same period in 2019 (47.5 vs 15.9 per 100,000 patients). Odds of pulseless electrical activity were nearly doubled, fewer patients returned to spontaneous circulation, and mortality exceeded 90%.

Much of the discussion around OHCA in recent weeks has centered around COVID-19’s complicity: is it causal at a biological level or is it hospital avoidance? The New York investigators did not have information on COVID-19 positivity, but the authors of the Paris paper report that approximately one-third of their cohort had confirmed or suspected SARS-CoV-2 infection. In these cases, Marijon explained to TCTMD in an email, they concluded that COVID-19 was “potentially causal, due to acute respiratory failure, direct cardiac toxicity, and myocarditis, but also an increase of thromboembolism events, including pulmonary embolism.” They also believe that some arrests could “potentially” be cardiac adverse events caused by investigational therapies such as hydroxychloroquine.

In the remaining two-thirds of patients, however, arrests likely stemmed from the delay in EMS arrival, difficulties reaching an EMS call center, and recommendations to the public to not go to emergency departments during this period, Marijon said. “Overall, we have seen much less myocardial infarction than usual, but much more severe ones—in other words, it is people with no COVID-19 diagnosis afraid to go to hospitals with STEMI.”

In Lombardy, investigators report a rate of confirmed or suspected COVID-19 of 25.5%, a proportion that they believe accounts for nearly three-quarters of the increase in OHCA cases in 2020 compared with prior years. But as Savastano told TCTMD, it will be very difficult to establish the true number of patients who arrested as a result of COVID-19 infection in Lombardy, particularly since autopsies were not possible on the patients who died at home.

“Based on our data, more than 70% of the excess of OHCA in 2020 had a suspected or confirmed diagnosis of COVID-19 so it’s quite reasonable to think that the greater part of the OHCA that occurred in 2020 was related to the infection—respiratory distress, myocardial injury, pulmonary embolism, [or] drug-induced or inflammatory [system]-mediated QT prolongation,” Salvatore said in an email to TCTMD. “Supporting this hypothesis is the strong, statistically significant correlation between the trend of COVID and the excess of OHCA.” But this also covers the indirect effects of the viral outbreak, he added: “The remaining part of OHCA is probably depending on complications of time-dependent cardiovascular diseases such as STEMI, which have been shown to be decreased as compared to 2019.”

Lessons for the Future

Timothy Henry, MD (The Christ Hospital, Cincinnati, OH), who early on raised alarm bells about the drop in hospital admissions for MI around the globe, says he believes a mix of COVID-19 and non-COVID-19 triggers are responsible for the cardiac arrest numbers now emerging. “Yes,” he said, “some of it is COVID-19, but the general feeling among cardiologists is that a significant share of the increased OHCA is related to the ‘missing STEMIs’ and we all obviously have individual cases where we know people waited and waited [to head to the hospital], then they had an arrest.”

The general feeling among cardiologists is that a significant share of the increase OHCA is related to the ‘missing STEMIs.’ Timothy Henry

Henry is optimistic that the message has gotten out to the public that they can’t postpone a heart attack until COVID-19 disappears and that hospitals can safely handle emergencies. The parts of the world still facing mounting numbers of infections will also benefit from the lessons learned at hard-hit regions earlier in the pandemic so that there’s less likelihood of hospitals being so overwhelmed that acute cardiac cases can’t be managed appropriately, he predicted. Fewer patients are getting intubated and put on ventilators, and therapies like convalescent plasma and remdesivir (Gilead Sciences) seem to be helping patients who are moderately sick from progressing to very severe disease that leaves them hospitalized for weeks or months.

This is also helping hospitals get back to elective procedures and cardiac surgeries cancelled when the focus was on saving beds for incoming COVID-19 patients. Getting back to the patients languishing on these waiting lists, said Henry, may also bring down the number of patients who progress to the point of needing emergency cardiac care.

Everyone who spoke with TCTMD agreed that keeping in touch with patients across the spectrum of cardiac care even in the midst of a pandemic is a lasting lesson to be learned from the sobering numbers of at-home cardiac arrests worldwide. “Do not neglect COVID-negative patients and organize hospitals to assure follow-up of patients,” Marijon advised. And for patients where face-to-face consultations are not an option, “optimization of remote consultations is the priority.”

COVID-19 at the PCR e-Course

Those messages were repeated by physicians from France, the United States, South Africa, and Italy who spoke last week at a special PCR e-Course 2020 session devoted to caring for the people “left behind” during COVID-19. Public campaigns, said Isabelle Durand-Zaleski, MD (Université de Paris, France), need to remind the public to seek care when they need it, to reassure them that risk of infection at hospitals is low, and “to explain to them that the mortality for AMI is higher than the combined risk of being infected and dying from COVID-19.”

Other priorities include physician payments for teleconsultation, optimization of patient transport, “special fees” to permit pharmacists and other health professionals to help with patient care, and compensation for increased expenditures related to enhanced hygiene measures, she said.

David Holmes Jr, MD (Mayo Clinic, Rochester, MN), also speaking in the PCR virtual session, made the point that a second surge is expected, even as many places are still dealing with the first. “We need to remember that the future is just around the corner, there are going to be more opportunities to address the issues that we failed to address the first time around. We need to make sure we have in place those approaches and strategies that we have found to work [so that] we can simultaneously take care of acute pandemic patients as well as the people left behind.”