Pacemakers that temporarily disrupt the heart's rhythm can contribute to his health/Jessica Wepner
The article was published with the approval of Scientific American Israel and the Ort Israel network
Sometimes it's better to get out of the rhythm. A new study shows that a calculated deviation from the normal rhythm of heart contractions can effectively treat heart failure.
About five million Americans are defined as having heart failure. In a quarter of them, the chambers of the heart fail to contract in perfect synchronization. Implantation of a pacemaker to restore the desired timing, a treatment known as biventricular pacing (CRT), often causes the heart to become stronger than the hearts of heart failure patients who have never experienced a heart rhythm disturbance. In essence, it seems that moving from asynchronization to synchronization is an efficient thing. This distinction led David Kass, director of the Center for Molecular Cardiology at Johns Hopkins University, to an intriguing question: Would heart failure patients with regular contractions benefit from mild desynchronization?
To answer the question, Cass and his colleagues implanted pacemakers in 23 dogs and induced heart failure in 17 of them. Then, in eight of them, the pacemakers forced the right side of the ventricle to contract too early compared to the left side of the heart for six hours a day. For the rest of the day, the device returned to a synchronized rhythm between the rooms.
After four weeks, the main measures of heart health showed a marked benefit in the condition of the dogs whose pacemakers were programmed for periods of irregular contractions. Their hearts pumped blood more strongly and the concentration of the proteins responsible for contractions and muscle structure increased. The results, published in December 2015 in the Journal of Applied Medicine, "contradict the popular belief in cardiac resynchronization therapy," says George Thomas, a cardiologist at New York Presbyterian Hospital and Weill Cornell Medical School, who was not involved in the study.
This treatment can be compared to the body's reaction to a vaccine. Just as injecting a weakened virus, or parts of the virus, stimulates the immune system's response, exposing the heart to a "dose" of asynchrony strengthens its function. Kass plans to study the approach in humans in about a year, but other cardiologists have already noticed the initial results. "It's a thought-provoking original idea," says David Frankel, who treats heart failure at the University of Pennsylvania. He believes that many patients will benefit from the benefit of breaking the rhythm.
