Download Clinical and electrocardiographic features

Clinical and electrocardiographic features
The first presenter was Dr Kristina Haugaa from Oslo University Hospital in Norway,
who talked about clinical and electrocardiographic features and differences between
athletes.
HCM has a reported prevalence of 1:500 and is a substantial contributor to sudden
cardiac death in young athletes. Diagnosis of HCM is made by echocardiography and
defined as septal wall thickness > 15 mm in the absence of history of hypertension or
other explanatory etiologies, according to Dr. Haugaa. Hypertrophic cardiomyopathy
is caused by mutations in genes encoding sarcomeric proteins and has autosomal
dominant inheritance. She stressed that genetic testing is recommended in HCM
patients and the yield of genetic testing is approximately 50%. A positive test
facilitates family screening and follow-up, whereas a negative test does not exclude
the diagnosis of HCM.
Mild HCM can be challenging to differentiate from athletes’ hearts. Dr Haugaa
stressed that an even bigger challenge is to evaluate whether an athlete with left
ventricular (LV) hypertrophy may have underlying HCM. To discriminate the two
entities, evaluation includes family history, ECG, exercise testing, echocardiography
with stress test, cardiac magnetic resonance imaging (MRI) and genetic testing.
Examples of features are that septal thickness rarely exceeds 15 mm in athletes and
hypertrophy is symmetric. On ECG, HCM patients and athletes both show increased
QRS voltage, which is frequently accompanied by bizarre ST-T changes in HCM, but
not in athletes. Ethnic differences must also be considered in the evaluation of the
ECG, since black athletes have more ECG changes than Caucasians.
Different echocardiographic patterns of left ventricular hypertrophy
The second presenter was Dr Nico Van de Veire from Ghent in Belgium, who told us
that echocardiography has a central role in the detection and quantification of left
ventricular hypertrophy (LVH). LVH can be caused by several clinical conditions
including arterial hypertension, aortic stenosis, endurance training, hypertrophic
cardiomyopathy and some rare conditions. Echocardiography together with clinical
information, ECG and other imaging conditions will help the clinician in the
diagnostic workup. For this, a comprehensive echocardiographic examination is
necessary, focusing on left ventricular and right ventricular function and structure,
diastolic function and evaluation of the cardiac valves. Prof Van de Veire highlighted
the echocardiographic features of these conditions in his talk.
Additional value of contrast-enhanced cardiac magnetic resonance
Cardiac MRI is very helpful to distinguish athlete’s heart from CHM according to
Prof Berhard Gerber from Woluwe-St. Lambert in Belgium. He stressed that most
athletes present with eccentric hypertrophy, characterized by increased LV enddiastolic volume index (EDVi) and right ventricular EDVi, homogenous wall
thickening <13mm and maintained LV EDV/mass and wall-thickness/EDV. He
convinced us that young athletes never present with late enhancement. However, late
enhancement on cardiac MRI is a typical finding in HCM and other pathologies, and
predicts worse outcome in these diseases. Therefore, late gadolinium enhancement
can be an important factor to help distinguish athlete’s heart from HCM. Overlap of
pathologies may exist, however, and there may be questions about the effect of
performance-enhancing drugs (doping) on LV remodeling in athletes.
Detraining and reversal remodelling
The last presenter was Prof. François Carré from Rennes in France. He taught us that
detraining will mainly result in a decrease of LV wall thickness and has less effect on
LV dilatation. The detraining effect is in favor of athlete’s heart, but even an athlete’s
heart might not decrease in thickness during detraining.
Detraining must be completed without any significant physical training. Detraining
must have a duration of 6 weeks to 6 months before we can review the results and the
patients must be studied on a regular basis. He told us that cardiac MRI is probably
better than echocardiography to evaluate the results of detraining.
Conclusion The session was very informative about this difficult topic and the
audience was active and had many questions for the presenters.