Premature ventricular contractions, a typical extra-systole arrhythmia, lowers the scaling exponent

摘要

We made our own DFA (detrended fluctuation analysis) program. We applied it to the heartbeat of various individuals. Healthy subjects showed a normal scaling exponent, which is near 1.0 (ranging 0.9 to 1.19 in our own temporary guideline). This is in agreement with the original report by Peng et al. long time ago. In the present study, we investigated a person who has an extra-systole heartbeat, called PVCs (premature ventricular contractions), and found that their arrhythmic heartbeat exhibited a low scaling exponent (around 0.7). Alternans, which is the heart beating in period-2 rhythms, exhibited a much low scaling exponent (around 0.6). We suggest that a device that employs a DFA program might be useful to check the heart condition, and would contribute not only in nonlinear physics but also in biomedical fields especially as a device to routinely check for predictors of heart disease in otherwise normal people.