Targeting an electrotonic effect with ablation: Management of a symptomatic long PR interval

Pseudo‐pacemaker syndrome with prolonged PR interval: A narrative review

“…Apart from our case and the one published by Ogunlade et al 6 . where no clear association between the patient’s past medical history and the presence of PPMS could be found, four etiologies of PPMS were identified in the remaining cases (n. 15), as follows: (1) Idiopathic PPMS related to poor AV nodal conduction (20% of cases); 2,14,16 (2) reversible inflammatory causes (13%) such as acute myocarditis 15 or acute rheumatic fever; 13 (3) cardiac surgery, 20 interventional procedures 11 or chest radiation 17 leading to the permanent damage of the normal AV conduction system (20%), and, finally, (4) PPMS due to manifest dual AV nodal physiology (DAVNP) occurring as a primary finding (27%) 10,12,16,19 or post slow pathway ablation for treatment of AVNRT (20%) 10,18,21 . In fact, in this latter group, two patients (66%) had residual DAVNP due to damage to the fast pathway, either as a complication of slow pathway ablation 21 or deliberate ablation as a treatment option for AVNRT 10 .…”

“…However, the stress test was able to reproduce the presenting symptoms of PPMS in about five (70%) cases 2,14,16–18 . Prolongation of the PR interval during the stress test was reported in four cases 14,16,17,19 out of whom 50% had DAVNP. In these cases, the exercise stress test showed normal—or slightly shortened—PR interval during maximal exercise but with progressively prolonged PR interval during early recovery while still in sinus tachycardia.…”

“…Chronotropic insufficiency was witnessed in two patients, 2,20 compared to three patients which were able to achieve at least 79% of their maximal predicted heart rate 2,14,17 . None of the patients developed high‐degree AV block, and only one patient developed blocked premature atrial contractions 19 . However, the stress test was able to reproduce the presenting symptoms of PPMS in about five (70%) cases 2,14,16–18 .…”

“…The retrieved 17 cases of PPMS—including our case report—are outlined in Table 1 2,6,10,12–21 . Most (88.2%) were adults with an average age of 47 years ranging from 13 to 86 years old.…”

“…Out of these patients, three (25%) had echocardiographic signs of AV dissociation. As to invasive evaluation, none of the investigated cases (59%) exhibited a prolonged His bundle to ventricular myocardium (HV) interval even in cases of PPMS due to DAVNP with remarkably prolonged PR intervals 10,19 …”