Amiodarone inhibits arrhythmias in hypertensive rats by improving myocardial biomechanical properties

The prevalence of arrhythmia in patients with hypertension has gradually attracted widespread attention. However, the relationship between hypertension and arrhythmia still lacks more attention. Herein, we explore the biomechanical mechanism of arrhythmia in hypertensive rats and the effect of amiodarone on biomechanical properties. We applied micro-mechanics and amiodarone to stimulate single ventricular myocytes to compare changes of mechanical parameters and the mechanism was investigated in biomechanics. Then we verified the expression changes of genes and long non-coding RNAs (lncRNAs) related to myocardial mechanics to explore the effect of amiodarone on biomechanical properties. The results found that the stiffness of ventricular myocytes and calcium ion levels in hypertensive rats were significantly increased and amiodarone could alleviate the intracellular calcium response and biomechanical stimulation. In addition, experiments showed spontaneously hypertensive rats were more likely to induce arrhythmia and preoperative amiodarone intervention significantly reduced the occurrence of arrhythmias. Meanwhile, high-throughput sequencing showed the genes and lncRNAs related to myocardial mechanics changed significantly in the spontaneously hypertensive rats that amiodarone was injected. These results strengthen the evidence that hypertension rats are prone to arrhythmia with abnormal myocardial biomechanical properties. Amiodarone effectively inhibit arrhythmia by improving the myocardial biomechanical properties and weakening the sensitivity of mechanical stretch stimulation.