The heart’s ability to contract and relax with each breath determines if it is functioning normally. Doctors can measure this ability — also known as left ventricular global longitudinal strain — after conducting an echocardiography test. A healthy heart is supposed to have a value of -20% to demonstrate that the muscles are supplying sufficient oxygen by contracting and relaxing lengthwise.
In a recent study that included 60 long Covid patients, researchers observed that close to half of them or 48% had lower values that averaged at around -17.8% — proving that their cardiac function was impaired even three months after getting infected with the SARS-CoV-2 virus.
Long Covid is characterized by symptoms like chronic fatigue syndrome/myalgic encephalitis, breathing difficulties, brain fog, mental health conditions like depression and anxiety, loss of smell and/or taste, persistent coughing, and body aches. In an attempt to address these issues, Israel-based researchers offered hyperbaric oxygen therapy to 60 long Covid patients in a randomized trial. This therapy involves being inside a pressurized environment while breathing 100% pure oxygen. That way, most of the body’s tissues get rejuvenated with sufficient oxygen supply. Following an infection that causes inflammation or an injury, tissues tend to receive insufficient or extremely low levels of oxygen which delays the body’s healing process.
The treatment is usually prescribed to those who experience decompression sickness after scuba diving. Hyperbaric oxygen therapy is also used for getting rid of bubbles of air in blood vessels and treating open wounds.
Out of the 29 patients who had impaired heart function, 16 underwent hyperbaric oxygen therapy. The other 13 were in the “sham group” where they were only given 21% pure oxygen through a mask during their treatment.
The team found that the 16 long Covid patients experienced an improvement in their heart function. Each one of them received 40 sessions of hyperbaric oxygen therapy spread over a span of eight weeks. Through a mask, they were exposed to 100% pure oxygen for 90 minutes. That included five-minute breaks following every 20 minutes of oxygen therapy.
After hyperbaric oxygen therapy, their left ventricular global longitudinal strain levels, which was previously 17.8%, shot up to -20.2 percent. Whereas those who were in the sham group reported an increase only up to -19.1 percent.
The findings suggest that hyperbaric oxygen therapy promotes recovery of cardiac function in patients with post-COVID syndrome. More research is needed to collect long-term results and determine the optimal number of sessions for maximum therapeutic effect,” said Marina Leitman from the Sackler School of Medicine in Tel Aviv University, Israel, in a press release.
The team presented their findings at the European Society of Cardiology’s 2023 conference called EACVI Congress in Barcelona on May 12.
“We used a sensitive measure of cardiac function which is not routinely performed in all centers. More studies are needed to determine which patients will benefit the most, but it may be that all long COVID patients should have an assessment of global longitudinal strain and be offered hyperbaric oxygen therapy if heart function is reduced,” added Leitman.