Four years after the COVID-19 pandemic began, heart-related deaths in the United States remain higher than normal, showing that the crisis has had lasting effects on the nation’s health system.
A new study from Harvard Medical School reveals that cardiac deaths in Massachusetts rose sharply in 2020 and have stayed elevated through 2023, well beyond the height of the pandemic. Despite the return to normal routines and reopened hospitals, people are still dying from heart conditions at much higher rates than before—and more of them are dying at home.
The study, published in JAMA Network Open, reviewed over 127,000 death certificates from Massachusetts between 2014 and mid-2024. Researchers found a clear shift beginning in March 2020.
Cardiac death rates, which once followed seasonal patterns with predictable winter peaks, broke from that rhythm and began spiking more dramatically year-round. In 2020 alone, cardiac deaths were 16% above expected levels. That number climbed to 17% in both 2021 and 2022, and remained 6% higher in 2023. Even this year, in 2024, some months have already come in well above historical averages.
What concerns researchers most isn’t just the overall increase—it’s where these deaths are occurring. More people are dying of heart-related causes in their own homes than ever before.
The sharpest increase in home deaths was seen between 2020 and 2022, a period when emergency departments were overwhelmed, elective procedures were postponed, and Americans were urged to stay home to avoid infection. Hospitals reported a drop in heart attack and stroke patients, not because these events became rarer, but because people stopped seeking help.
Dr. Jason Wasfy, a cardiologist at Massachusetts General Hospital and lead author of the study, said the findings reflect deep disruptions in how Americans access emergency care. According to Wasfy, these deaths likely represent missed opportunities to intervene with highly time-sensitive treatments, such as clot-busting medications, artery-clearing procedures, or defibrillators that require hospital care. The fact that hospital deaths also remained elevated suggests that even when patients did seek help, the system wasn’t always prepared to deliver timely care.
This trend isn’t limited to Massachusetts. The United Kingdom experienced a similar rise in heart-related deaths at home in 2020, but the new Harvard analysis stands out because the elevated numbers in the U.S. have persisted for years. Massachusetts is considered one of the best-prepared states, with high vaccination rates and a strong healthcare network. If the situation is this severe there, it raises serious questions about outcomes in rural or under-resourced areas across the country.
Researchers used statistical models to estimate what cardiac death rates should have looked like between 2020 and 2024 based on pre-pandemic patterns. The deviations were stark. The average age of the deceased was 77, and women accounted for nearly half of all deaths. Every excess death signals a moment when care may have come too late—or not at all.
While the direct impact of the virus on the heart is still being studied, the broader effects of disrupted care are undeniable. During the worst of the pandemic, many Americans simply avoided hospitals out of fear or confusion. That behavior appears to have changed the way people respond to cardiac symptoms even now, with deadly consequences.
The report calls for renewed attention to how people access emergency care, especially in cases where minutes can mean the difference between life and death. Relying solely on hospital admission data no longer provides a full picture. As the authors note, a decline in hospital cases does not necessarily mean fewer heart attacks are happening—it may just mean more people are dying in places where help never arrives.
This troubling pattern suggests that the nation is still living with the hidden costs of COVID-19, especially when it comes to the most common cause of death in the United States: heart disease. And it’s happening quietly, behind closed doors, where fewer ambulances are called and fewer lives are saved.