sino-atrial block

例句：

1. 1. The patient's heart rate was significantly reduced during the procedure.
   在手术过程中，患者的心率显著降低。
2. 2. Sino-atrial block is a common complication of heart surgery.
   心房阻滞是心脏手术的常见并发症。
3. 3. The patient required an immediate pacemaker implantation due to severe sino-atrial block.
   由于严重的心房阻滞，患者需要立即植入起搏器。