Arrhythmia monitoring in HCM patients is used not only for determining risk of sudden death and potential need for an implantable defibrillator, but also for detecting atrial fibrillation (AFib) and implementing anti-coagulation for stroke prevention.
A recent paper provides an overview of the usefulness of arrhythmia monitoring in patients with HCM.
THERE ARE DIFFERENT TYPES OF EVENT MONITORS
There are several varieties of event monitor available: some are used for a day or two, some for a couple of weeks, and some implantable devices such as implantable loop recorders can be used to record rhythm abnormalities for several years.
WHEN IS MONITORING APPROPRIATE?
The 2020 AHA/ACC Guidelines recommend arrhythmia monitoring at initial evaluation and then every 1 or 2 years thereafter. Extended monitoring is also recommended for patients with palpitations or lightheaded episodes in order to ascertain and treat the cause.
MONITORING FOR ATRIAL FIBRILLATION
This paper highlights the fact that patients with HCM who have Afib risk factors should undergo an initial screening for AFib and then repeat arrhythmia monitoring every 1 to 2 years thereafter.
IMPORTANT NOTE -The prevalence of AFib in HCM is 4 to 6 times higher than in the general population. Documented AFib of more than 24 hours duration requires lifelong treatment with anti-coagulants in order to avoid a thromboembolic stroke.
MONITORING FOR NON-SUSTAINED VENTRICULAR TACHYCARDIA (NSVT)
Episodes of NSVT found during monitoring, especially when looked at in conjunction with other risk factors, may support the recommendation of an implantable defibrillator.
In a recent study, researchers examined whether cardiac MRI results might help predict which patients would would go on to develop atrial fibrillation (AFib) that was serious enough to require hospitalization, require electrical cardioversion or catheter ablation, or identify those patients who might go on to develop permanent AFib.
The study found that the major predictors of these serious AFib consequences in HCM were those who were of older age, those with an increased BMI (this was especially important in patients under age 33), increased left atrial volume index as seen on cardiac MRI (this was especially important in middle-aged patients), reduced left atrial contractile function (this was especially important in middle-age and older patients), and moderate or severe mitral valve regurgitation.
The researchers concluded that using cardiac MRI to measure left atrial volume and contractile function might help medical providers ability to intervene before major AFib develops in HCM patients, specifically by helping patients find ways to reduce their weight and by treating mitral regurgitation and left atrial function more aggressively.
The full paper can be found here and for a summary from Cardiac Rhythm News click here.
HCM specialists at Tufts Medical Center and Toronto General Hospital have devised a formula which they hope will help predict which HCM patients may go on to develop atrial fibrillation (“AFib”) over time. This tool can assist doctors in determining which patients are at highest risk so that these patients can be closely monitored and treated appropriately. AFib can be extremely dangerous for HCM patients since it can precipitate a stroke if not appropriately treated.
Because existing tools to predict atrial fibrillation have not proven to be accurate for HCM patients, the researchers studied 1900 HCM patients with the goal of devising a new tool to help HCM patients and their physicians learn their personal risk for AFib over a 2 and 5 year period.
Continue reading “Can This Formula Predict AFib in HCM Patients?”
If you are looking for a good survey of current practices in the treatment of HCM, a recent article published in the journal Structural Heart by Dr. Ahmad Masri and the team at Oregon Health and Sciences University (OHSU) provides an informative overview of thirty controversies and considerations in the treatment of HCM. This article explains in some detail how the doctors at this HCM Center approach these situations.
Continue reading “HCM Treatment: The View from OHSU”
A recent study published in Clinical Research in Cardiology found that atrial fibrillation is a frequent complication of HCM and can be an important predictor of negative outcomes.
These findings suggest that practitioners should aggressively screen for and treat atrial fibrillation in HCM patients to improve long term outcomes.
The software update which allows the Apple Watch 4 to take an EKG and to detect atrial fibrillation went live last week. In anticipation of the availability of these functions, I purchased an Apple Watch 4. As soon as the software was available, I downloaded it and have used it every day since. So far, I am quite pleased with my purchase. The technology works very well, even despite the fact that I have an implantable pacemaker/defibrillator.
The strip it takes looks like this:
You can send a strip via email to your doctor, and all are saved for posterity on your Iphone. (NOTE: YOU MUST HAVE AN IPHONE CAPABLE OF RUNNING THE SOFTWARE IN ORDER TO USE THE WATCH).
And, as long as you tell the software that you have never been diagnosed with atrial fibrillation, if it detects atrial fibrillation while you wearing the watch, it will send you an alert. I haven’t gotten such an alert yet and hope not to!
This article provides a pretty accurate history of handheld consumer EKG devices along with a description of what it is like to download and use the Apple software.
And here is a story about a man whose watch spotted his previously undiagnosed Afib. After a trip to the emergency room, he was able to receive proper treatment and avert a potential health crisis.
A recent paper published in the journal Circulation looked at the clinical course of approximately 4,600 HCM patients over the course of more than 24,000 clinical years, which the paper describes as the largest comprehensive cohort of HCM patients ever studied.
This study examined patients from eight high volume HCM centers which aggregated their institutional data into a database known as the Sarcomere Human Cardiomyopathy Registry (or the acronym the “SHaRe” for short). The results of the study showed that, in general, HCM patients are at substantially elevated risk for atrial fibrillation and heart failure, and have significantly higher mortality rates than that of the general U.S. population.
Continue reading “HCM Researchers Put their Heads Together to Improve Lives of HCM Patients”
A recent paper by doctors at Tufts University’s HCM Center found that transient episodes of atrial fibrillation (AF) are treatable and do not often progress to permanent AF.
This study found that AF was not a frequent cause of death by heart failure or sudden cardiac arrest. However, the researchers identified AF as an important cause of stroke in HCM patients. Therefore, they recommend a low threshold for starting HCM patients on anti-coagulants following an initial AF episode.
Researchers in this study analyzed statistics from 1558 HCM patients, 20% of whom experienced AF. 74% experienced only sporadic episodes, while 26% went on to develop permanent AF.
At the time of publication, 91% of the 277 of the patients included in the sample were still alive and between the ages 49 and 75 years old.
According to an accompanying editorial by Italian HCM expert Dr. Paolo Spirito, the outlook for HCM patients with atrial fibrillation has improved over the last twenty years due to significant advances in HCM treatment over that time period such as ICD implantation and myectomy, along with aggressive anti-coagulation for atrial fibrillation patients.
Spirito also noted that it is difficult to predict whether a given HCM patient will go on to develop permanent Afib after a single episode since many will not. Additionally, permanent afib can be well tolerated when there is contemporaneous control of heart rate. Therefore, anti-arrhythmic medications, which can cause unpleasant side effects, may not be necessary for HCM patients with afib as long as anti-coagulation measures are taken.
The same Fitbit you wear to count your steps may soon have an additional purpose: it could detect atrial fibrillation.
Atrial fibrillation is an irregular heartbeat which could cause a stroke if not properly treated. Yet, it often goes unnoticed by a person experiencing it.
According to this story in Time, Fitbit is developing software which would enable its existing trackers to detect afib, and thus allow time for appropriate action before it is too late.
This technology could be of great benefit to heart patients. Not only does the Fitbit encourage you to exercise, it might just save your life!