close
- Increased automaticity in AV node + decreased automaticity in sinus node.
- Causes of Accelerated Junctional Rhythm :
Digoxin toxicity (the classic cause of AJR)
Beta-agonists, e.g. isoprenaline, adrenaline
Myocardial ischaemia
Myocarditis
Cardiac surgery
- Junctional Escape Rhythm : 40-60 bpm
- Accelerated Junctional Rhythm : 60-100 bpm
- Junctional Tachycardia : > 100 bpm
- Narrow complex rhythm
- Retrograde P waves may be present
and can appear before, during or after the QRS.
- Retrograde P waves are usually
inverted in the inferior leads (II, III, aVF), upright in aVR + V1.
- Short PR interval (< 120 ms)
indicates a junctional rather than atrial focus.
- There may be associated ECG features of digoxin effect or digoxin toxicity.
- Rapid AJR may be difficult to distinguish from AVNRT or AVRT.
typically non-responsive to vagal manoeuvres
- AJR with aberrant conduction may be difficult to distinguish from AIVR
fusion or capture beats indicates a ventricular rather than junctional focus.
- ESRD 病人出現 junctional rhythm 要立即想到高血鉀的可能性！
- 透析病人發生有症狀的心搏過緩, 裝上 EKG monitor 與做 complete EKG 是第一要務
- 總是優先考慮是否為高血鉀造成的問題
- 詢問用藥病史 (beta-blocker, CCB or digoxin poisoning)
- 有無缺血性心臟病或傳導系統纖維化引起 AV block、SSS 與 VHD 的可能 ？
- 鉀離子稍微高的情況下發生的 junctional rhythm
透析治療會改善, 但不代表病人的問題單純是高血鉀所引起的, 轉介心臟科進一步評估
- 這些 ESRD 病人
有些也許本身就有竇房節功能有不良 ( SA node dysfunction)
會因為稍微高的鉀離子, 酸中毒, 或其他 uremic toxin 讓 SA node 的功能較易被抑制
而跳出 junctional rhythm
http://www.drroger.info/hd/bradycardia/
全站熱搜
留言列表
CV (7)
