Prognosis
The prognosis is related to the degree of AV block and the severity of associated symptoms. In certain conditions, such as sarcoid or amyloid heart disease or acute anterior MI, the underlying condition strongly determines prognosis.
Non-randomised studies strongly suggest that permanent pacing improves survival in patients with third-degree AV block, especially if syncope has occurred. In patients with type II second degree AV block, especially when the block is infranodal or the QRS is wide, prognosis is compromised. Mortality remains high in patients with acute myocardial infarction in whom AV block occurs, as it reflects extensive myocardial damage. AV block occurring with inferior MI, rather than an anterior MI, is more likely to resolve. Registry data indicate that symptomatic cardiac sarcoidosis with heart block, ventricular arrhythmias, or LV dysfunction is associated with a poor prognosis.[9] Along with the presence of concurrent myeloma, presence and severity of cardiac involvement in primary amyloidosis determines prognosis.[48]
Asymptomatic first-degree or type I second-degree AV block
First-degree AV block has been associated with about a 2-fold increase in the probability of atrial fibrillation, a 3-fold increase in the probability of pacemaker implantation, and an increase in all-cause mortality.[2]
Asymptomatic advanced AV block (type II second-degree or third-degree)
In symptomatic patients with irreversible AV block, symptoms are likely to persist or potentially worsen. Patients with irreversible advanced AV block (type II second-degree or third-degree) are at high risk for progression to third-degree AV block or ventricular asystole.[39] As such, these patients should be strongly advised to undergo permanent pacemaker implantation.
Symptomatic AV block treated with a permanent pacemaker
These patients have an excellent prognosis, with a low rate of complications related to the pacemaker.
Use of this content is subject to our disclaimer