Optical mapping confirmed prolonged activation time and reduced conduction velocity in both sinus rhythm and pacing modes. Programmed electrical stimulation experiments demonstrated a high incidence of induced ventricular tachycardia (VT) in overexpression mice, while no VT was induced in the control group. Additionally, flecainide did not induce VT, and there were no spontaneous deaths or significant differences in cardiac function between the two groups over six months. In summary, USP10 overexpression leads to cardiac conduction block and induces VT in mice.

(A) Schematic diagram showing study design. (B and C) Representative tel emetry ECG recordings showed that the P-wave duration, PR interval, and QRS duration were prolonged in mice with USP10 overexpression. Ten mice were recorded for each group. (D) Representative telemetry ECG recordings for 48 h per mouse showed spontaneous cardiac conduction block and sinus pause in mice with USP10 overexpression. Nine mice were used for each group. (E and F) Contour map showing optical mapping results of ventricular activation in AAV9-USP10 mice. E: sinus mode, or F: pacing mode. Seven mice were used for each group. The data were shown as mean ± SE. Student’s t-tests were used to test significance *P < 0.05, **P < 0.01, ns, not significant.

Cardiovascular research (IF13.3)

DOI: 10.1093/cvr/cvaf214