| Comparative effects of three calcium antagonists, diltiazem, verapamil and nifedipine, on the sinoatrial and atrioventricular nodes. |
| The sinoatrial node is, however, unaffected. |
| When the sinoatrial node starts to malfunction it can cause dangerously slow or erratic rhythms to develop. |
| In some circumstances, paroxysmal supraventricular tachycardia will abruptly terminate, and the sinoatrial node will not take up normal sinus rhythm. |
| Sinoatrial reentrant tachycardia, a rare form of supraventricular tachycardia in children, involves reentrant in and around the sinoatrial node. |
| While the sinoatrial node pacemaker is dominant, occasional spontaneous premature beats may arise anywhere in the conduction system. |
