Third degree AV block surgery
|
Third degree AV block Microchapters | |
|
Diagnosis | |
|---|---|
|
Treatment | |
|
Case Studies | |
|
Third degree AV block surgery On the Web | |
|
American Roentgen Ray Society Images of Third degree AV block surgery | |
|
Risk calculators and risk factors for Third degree AV block surgery | |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Cafer Zorkun, M.D., Ph.D. [2]; Raviteja Guddeti, M.B.B.S. [3] Soroush Seifirad, M.D.[4]
Surgery
Implantation of permanent pacemakers in both asymptomatic and symptomatic patients is usually done. Asymptomatic Mobitz II are prone to be converted to symptomatic or third degree heart AV block. Thus, they should be considered for a pacemaker even if asymptomatic.
Pacemaker Indications
Permanent pacemaker implantation indications in complete heart block include:
- Patients with permanent atrial fibrillation and symptomatic bradycardia.
- Patients with acquired second-degree Mobitz type II heart block, third-degree atrioventricular block not attributable to reversible causes, require a permanent pacemaker regardless of symptoms.
- Patients with the following neuromuscular diseases with evidence of second-degree and third-degree atrioventricular block require permanent pacemaker regardless of the symptoms.
- Myotonic dystrophy type 1
- Kearns-Sayre Syndrome
- Patients with symptomatic atrioventricular block as a consequence of guideline-directed management for which there is no alternative treatment and continued treatment is clinically necessary; a permanent pacemaker is recommended to improve symptoms.
- Patients with infiltrative cardiomyopathies, such as cardiac sarcoidosis or amyloidosis, and second-degree Mobitz type II atrioventricular block, high-grade atrioventricular block, or third-degree atrioventricular block with a life expectancy of greater than one years; permanent pacemaker is reasonable.
- Symptomatic bradycardia (including heart failure)
- Ventricular arrhythmias presumed to be due to AV block
- Awake, symptom-free patients in sinus rhythm with documented periods of asystole 3 seconds or longer
- Any escape rate less than 40 beats/min
- Escape rhythm that is below the AVN
- Asymptomatic patients with atrial fibrillation and bradycardia with 1 or more pauses of at least 5 seconds or longer
- After catheter ablation of the AV junction
- Postoperative complete heart block
- Average resting heart rate of over 40 beats per minute while awake in an asymptomatic patient
- Certain neuromuscular diseases which have a high potential for unpredictable rapid progression of conduction blocks
High risk patients for pacemaker implantation after heart surgery include:
- Those with preexisting conduction disturbances, and
- Those undergoing aortic valve replacement (TAVI)[2]
In such patients implantation of pacemaker is recommended at 5 days after surgery.
Pacing Mode
VVI pacing mode was widely used in the past. But this mode has been shown to be associated with AV dyssynchrony leading to pacemaker syndrome. A dual chamber DDD pacemaker is preferred over a single chambered VVI pacemakers as it maintains physiologic AV synchrony. A dual-chamber artificial pacemaker is a type of device that typically listens for a pulse from the SA node and sends a pulse to the AV node at an appropriate interval, essentially completing the connection between the two nodes. Pacemakers in this role are usually programmed to enforce a minimum heart rate and to record instances of atrial flutter and atrial fibrillation , two common secondary conditions that can accompany third degree AV block.
References
- ↑ Facenda-Lorenzo M, Hernández-Afonso J, Rodríguez-Esteban M, de León-Hernández JC, Grillo-Pérez JJ (2012). "Cardiac Manifestations in Myotonic Dystrophy Type 1 Patients Followed Using a Standard Protocol in a Specialized Unit". Rev Esp Cardiol. doi:10.1016/j.recesp.2012.08.011. PMID 23194837. Unknown parameter
|month=ignored (help) - ↑ Merin O, Ilan M, Oren A; et al. (2009). "Permanent pacemaker implantation following cardiac surgery: indications and long-term follow-up". Pacing Clin Electrophysiol. 32 (1): 7–12. doi:10.1111/j.1540-8159.2009.02170.x. PMID 19140907. Unknown parameter
|month=ignored (help)