Since the early 1960s, surgical septal reduction, also known as septal myectomy, has been used as a therapy for the treatment of obstructive hypertrophic cardiomyopathy. Pioneered at the National Institute of Health by cardiac surgeon Dr. Glenn Morrow, himself a HCM patient, septal myectomy has become a mainstay of the HCM treatment arsenal.
An alternative to septal myectomy, alcohol septal ablation (ASA), was first performed by Ulrich Sigwart in the United Kingdom at the Royal Brompton Hospital in London in 1994.
For many years, the indications for ASA procedures has been limited to older patients with obstructive HCM who were not otherwise healthy enough to undergo open heart surgery. However, some doctors are now advocating to expand the indications for ASA to include symptomatic younger patients.
(For more information about myectomy and ASA, click here and scroll to bottom of page).
Continue reading “Should Alcohol Septal Ablation Be Considered for Younger Patients?”
According to an editorial published in yesterday’s issue of Circulation by Drs. Barry and Martin Maron together with Dr. Ethan Rowin, the outlook for most HCM patients is much rosier than previously thought.
According to current estimates, which take into account contemporary disease treatments and risk management strategies, the risk of death from HCM is only .5% per year or 2.5% over 5 years, which is similar to the degree of risk in the general non-HCM population.
Hence, according to the editorial, HCM patients should be reassured about their long term prognosis.
Researchers from around the globe have joined together to study an unlikely subject in order to understand the genetics of HCM according to a paper published today in the journal eLIFE.
Dr. Christine Seidman, a cardiologist from Harvard Medical School, Dr. James Ware a geneticist from the MRC London Institute of Medical Sciences at Imperial College London, and Dr. Raúl Padrón, a structural biologist at the Venezuelan Institute for Scientific Research, have joined forces in order to study the tarantula.
The reason for their focus on the tarantula is because the proteins comprising the muscles inside the furry spider are actually very similar to proteins inside the human heart.
Dr. Seidman, who had taken note of Dr. Padrón’s work with spiders, sought him out at a meeting to discuss the similarity of heart proteins to those in tarantula muscles and asked him whether they might collaborate.
By studying the way that the spider proteins interact with one another, the scientists hope that they will gain further insight into whether and how certain genes cause different types of hereditary cardiomyopathy, including hypertrophic and dilated.
I hope that they find the answers soon, before any tarantulas escape from their lab!
In this editorial by Lee Cooper published in today’s issue of Wired Magazine, a patient with Long QT Syndrome makes the case for the use of pre-implantation genetic diagnosis (PGD) used in tandem with in vitro fertilization (IVF) as a means to eliminate hereditary disease.
This technique has already been used in HCM; most successfully in cases caused by a single, identifiable genetic mutation. PGD combined with IVF is a potentially viable option for patients with HCM who are planning to grow their families.
Of course, there are many ethical issues raised with the use of this technology, and the use (or non-use) of these technologies is a very personal decision. Perhaps such moral uncertainty is what caused Cooper’s doctors to be “reticent to discuss IVF head on” and “bashful about the idea of removing [t]his disease from [his] lineage.”
As Cooper says in the editorial “…we can, and we must be able to speak clearly about the best ways to prevent disease if we are serious about eliminating it.” If every option were to be laid out on the table for consideration by the patient, then s/he would have the freedom to make a final decision in accordance with his/her own unique set of values.
What do you think?
Researchers in Norway have demonstrated that patients who carry a HCM gene show reduced cardiac volume when compared to healthy individuals. Patients with overt HCM show even further reduction to their cardiac volume than those who merely carry the gene.
Although the gene positive individuals lacked the characteristic left ventricular wall thickening of HCM, diastolic and systolic volumes were reduced when compared to healthy individuals. Hence, the researchers concluded that a person who is gene positive for the disease may show reduced volume before developing hypertrophy.
The study included 180 patients with left ventricular hypertrophy, 100 patients who carried the HCM gene but did not show signs of left ventricular hypertrophy, and 80 healthy individuals.
The researchers theorize that early changes in HCM result from the gradual stiffening of the left ventricle, which contributes to filling changes before anatomical thickening is apparent. These changes will likely worsen as the disease progresses.
The researchers suggest future long term studies of gene positive individuals with small cardiac volume who show signs of diastolic and systolic dysfunction. These patients, they suggest, are the most likely to go on to develop HCM.
A study published this week by HCM researchers in Canada found that double mutations in patients with hypertrophic cardiomyopathy are much less common than previously thought. In particular, researchers found that except for those with double mutations in the gene MYBPC3, there is not much data to support the finding that there is a worse clinical course for those patients who have double HCM mutations.
Hence, in the absence of extraordinary circumstances, such as two MYBPC3 mutations, the researchers caution that double mutations should not be the sole justification for the insertion of an implantable defibrillator.
The study looked at patients >18 years of age who underwent genetic testing at the Toronto General Hospital between January 2005 and June 2016. Out of a sample of 1411 patients, 9% of those who were gene-positive patients had 2 genes, but only in 1 case (0.4%) were both genes classified as those known to cause HCM.
In addition to looking at their own patients, the researchers also re-examined data from previously published studies. Similarly, they found when they re-analyzed the data that only 0.4% of the 8% of patients previously found to have double mutations in fact carried multiple pathogenic mutations.
When a patient is the only person in the family ever diagnosed with HCM, s/he will often wonder whether their disease is, in fact, genetic. S/he will also wonder whether it will be necessary for all first degree relatives to undergo serial screenings for the rest of their lives.
In answer to this concern, Australian researchers have recently identified a subset of HCM patients who appear to have a non-familial form of the disease and whose relatives may be candidates for less stringent screening protocols.
The study, just published in Circulation: Cardiovascular Genetics by Dr. Jodie Ingles and Dr. Chris Semsarian, found that this group, having neither genetic mutation associated with HCM nor family history of HCM, comprises approximately 40% of all HCM patients. Non-familial HCM patients are more likely to be older when diagnosed, and they often present with non-asymmetric hypertrophy and hypertension. And, these HCM patients appear to have a more favorable clinical course, with a better track record of survival from major cardiovascular events.
The researchers point out that by sorting patients into more distinct subgroups, doctors will be able to provide more personalized and evidence-based care to patients and their families. In particular, their recommendation is that first-degree relatives of non-familial HCM patients need only be screened one or more times in adulthood. Less frequent follow up surveillance is also suggested, in contrast with the more intensive screening guidelines recommended for family members of patients with familial HCM.
Editor’s note: This is our first interview feature on HCMBeat. In the future, we hope to feature more interviews with other HCM researchers who have published articles of interest to the HCM community.
By now, you have probably already heard the buzz about RESET- HCM – a study about the effects of exercise on HCM patients conducted by Dr. Sara Saberi and Dr. Sharlene Day at the Hypertrophic Cardiomyopathy Clinic of the University of Michigan’s Frankel Cardiovascular Center in collaboration with Dr. Matthew Wheeler and Dr. Euan Ashley of Stanford’s HCM Center. The findings were presented at the American College of Cardiology Conference on March 17, 2017 held in Washington D.C. and were the subject of this feature on HCMBeat.
Recently, Cynthia Waldman of HCMBeat had the opportunity to sit down with Drs. Saberi and Day for a detailed conversation (over Skype) about the study. What follows is a transcript of their conversation (which has been edited for readability).
Continue reading “RESET-HCM: Rethinking Exercise for HCM Patients – Interview with Dr. Sara Saberi and Dr. Sharlene Day”
Results from a recent study conducted at the University of Michigan and Stanford show that patients who participated in a moderate-intensity cardiovascular exercise program showed a small, but statistically significant increase (6%) in exercise capacity over those who did not participate in the program. Of note, no adverse events were reported in any of the 136 adults who participated in the RESET-HCM study over its four-month duration. These results were announced over the weekend at the American College of Cardiology meeting in Washington, D.C.
A companion editorial noted that this study is important for establishing the positive impact of exercise on HCM patients. Now, the need is for future research to establish safe exercise guidelines for HCM patients. Many remain reluctant to exercise due to fear of suffering an adverse event during exercise.
Here is a video interview with one of the authors of the study, Dr. Sara Saberi, discussing the findings at ACC.
Stay tuned to HCMBeat for more about this important work which will hopefully lead to improved quality of life for HCM patients.
A recent retrospective study of patients at Minneapolis Heart Institute and Tufts Medical Center published in the Journal of the American College of Cardiology found that HCM patients who also had left ventricular apical aneurysms were at increased risk of sudden cardiac death and stroke. However, with increased surveillance and appropriate treatment, including the implantation of a implantable defibrillator, radiofrequency ablation and/or anti-coagulation, as appropriate, the authors suggest that the increased risk can be neutralized.
A summary of this article can be found here.