Final answer:
Perioperative management of heart block involves using pacemakers for both bifascicular and third-degree AV blocks, with the third-degree block necessitating a pacemaker due to no correlation between atrial and ventricular activity on the ECG.
Step-by-step explanation:
Perioperative management of heart block involves addressing the different types of atrioventricular (AV) blocks that a patient may present with. The management typically focuses on ensuring stable cardiac rhythm and preventing bradycardia-related complications.
1) Bifascicular Block
A bifascicular block, which refers to the simultaneous blockage of two of the three fascicles of the heart's conduction system, may require a permanent pacemaker (PPM) if the patient is symptomatic or if the block is associated with an increased risk of progression to higher-degree block. Bifascicular blocks can be identified on an electrocardiogram (ECG).
2) Third-Degree AV Block
A third-degree AV block, also known as a complete heart block, is characterized by a complete disassociation between atrial and ventricular activity. The ECG would show no correlation between P waves and QRS complexes. In this case, an artificial pacemaker is typically implanted to deliver electrical impulses to the heart muscle, thus ensuring effective contraction and blood pumping. Some pacemakers also incorporate defibrillators to address potential life-threatening arrhythmias.
3) Cannot be Fixed
Heart blocks that cannot be fixed usually refer to situations where the condition is inoperable or irreversible with current medical technology. However, this is highly context-dependent, and pacemakers are often a solution for many types of heart block.