Trine Synnøve Fink Håland has used modern cardiac ultrasound methods to increase our knowlegde about the genetic heart disesase hypertrophic cardiomyopathy.

MAIN RESULTS:

1. Mechanical dispersion is a strong and independent marker of ventricular arrhythmia in patients with hypertropic cardiomyopathy.
2. Echocardiography can distinguish hypertrophic from non-compaction cardiomyopathy.
3. Smaller cardiac volumes can explain why ejection fraction is preserved in hypertrophic cardiomyopathy.

THESIS DEFENCE:

Thesis: Hypertrophic cardiomyopathy – Systolic function, differential diagnosis and risk stratification
Candidate: Trine Synnøve Fink Håland
Time: October 18, 2018 at 14:15
Place: Oslo University Hospital, Rikshospitalet: Seminar room 1 (B2.U001)
Link to university website (in Norwegian)

SUMMARY:

(1) In hypertrophic cardiomyopathy, the left ventricular wall is thicker than normal. This genetic heart disease increases the risk of ventricular arrhythmias and sudden death. The echocardiographic parameters global longitudinal strain and mechanical dispersion are related to arrhytmia in this patient group, according to Håland’s results. Mechanical dispersion is a measure of dyssynchrony of the left ventricle, whereas global longitudinal strain is a sensitive measure of systolic heart function.

25 % of the 150 patients in the study had documented episodes with ventricular arrhytmia. Cardiac fibrosis assessed by late gadolinium enhancement on cardiac MR was also related to arrhythmia, and strongly associated with mechanical dispersion.

(2) Left ventricular non-compaction cardiomyopathy is a rare heart disease with high mortality from sudden cardiac death at a young age. The disease affects the heart somewhat similarly to hypertrophic cardiomyopathy, but the two diseases require different treatments. By using sensitive echocardiographic methods, Håland and co-workers have found a way to distinguish non-compaction from hypertrophic cardiomyopathy.

The study includes left ventricular assessment of 25 patients with non-compaction cardiomyopathy, 50 patients with hypertrophic cardiomyopathy, and 50 healthy control persons. Global longitudinal strain was similar in both diseases, but apical function was significantly worse in non-compaction compared to hypertrophic cardiomyopaty. Moreover, lower ejection fraction, lower maximum wall thickness and a higher number of trabeculations were present in non-compaction cardiomyopathy.

(3) Patients with hypertrophic cardiomyopathy generally have a well preserved ejection fraction, but reduced global longitudinal strain. According to Håland’s results, this paradox can be explained by smaller cardiac volumes in patients, compared to healthy persons.

180 patients with hypertrophic cardiomyopathy, 100 genotype-positive patients without the disease, and 80 healthy individuals contributed to the study. The genotype-positive individuals without increased wall thickness also had somewhat reduced cardiac volumes and subtle changes in systolic function compared to the healthy participants.

REFERENCES:

(1) Haland, T. F., Almaas, V. M., Hasselberg, N. E., Saberniak, J., Leren, I. S., Hopp, E., Edvardsen, T., & Haugaa, K. H. (2016). Strain echocardiography is related to fibrosis and ventricular arrhythmias in hypertrophic cardiomyopathy. European Heart Journal–Cardiovascular Imaging, 17(6), 613-621.

(2) Haland, T. F., Saberniak, J., Leren, I. S., Edvardsen, T., & Haugaa, K. H. (2017). Echocardiographic comparison between left ventricular non-compaction and hypertrophic cardiomyopathy. International journal of cardiology, 228, 900-905.

(3) Haland, T. F., Hasselberg, N. E., Almaas, V. M., Dejgaard, L. A., Saberniak, J., Leren, I. S., Berge, K. E., Haugaa, K. H., & Edvardsen, T. (2017). The systolic paradox in hypertrophic cardiomyopathy. Open heart, 4(1), e000571.