Spontaneous Oscillatory Contractions (SPOC): assessing the contractility of human familial cardiomyopathies

A. Li, D. King, E. Kable, F. Braet, T. Kagemoto, P. MacDonand, S. Ishiwata, C. dos Remedios

Research output: Contribution to journalMeeting abstractpeer-review


Familial cardiomyopathies are common causes of genetic heart failure. This study induced spontaneous oscillatory contractions (SPOC) in left ventricular fibre bundles isolated from familial dilated (FDCM) and hypertrophic cardiomyopathy (HCM). We aim to identify contractile parameters that functionally distinguish these myocardial disease states from age-matched non-failing donor hearts.

SPOC is a physiological state that auto-oscillates intermediate to muscle in full contraction and relaxation. It exhibits characteristic sawtooth oscillations with a rapid lengthening (relaxation) and slow shortening (contraction) phase equivalent to diastole and systole, respectively. This stable auto-oscillatory property of SPOC is ideal for repetitive measurements of contraction and relaxation of cardiac muscle in failure.

Preliminary evaluations reveal several interesting findings. These findings demonstrate that

1. SPOC can distinguish FDCM from HCM, and from age-matched non-failing donor hearts.
2. HCM patients tend to exhibit lower SPOC amplitude and shorter period of contraction compared to non-failing donors.
3. FDCM patients have a higher amplitude and faster relaxation rate than non-failing donors.
4. there is a progressive deterioration in amplitude, and relaxation rates and period in HCM patients separated by ejection fraction.
5. slower rate and shorter period of relaxation is evident in HCM with MYBPC3, mutation and is consistent with diastolic dysfunction characteristic of HCM.

We conclude that SPOC yields a range of functional parameters that can be used to evaluate the functional state of human heart muscle fibres. It may provide a valuable set of parameters that can objectively assess the state of human heart failure.
Original languageUnknown
Pages (from-to)S64
Number of pages1
JournalHeart, Lung and Circulation
Publication statusPublished - 2012
Externally publishedYes

Cite this