Clinical Case.
The clinical case focuses on a 19-year-old women with a non-congenital third degree atrio-ventricular block (AVB), symptomatic for dyspnoea for mild efforts, with structurally normal heart, no other comorbidities and no medications taken. Both the exercise stress test and the atropine test documented a sinus tachycardia at 190 bpm with a 2:1 AVB and a narrow QRS, and 1:1 AV conduction until a sinus rate of 90 bpm.
She underwent CNA procedure, targeted the inferior paraseptal ganglionated plexus (IPSGP), both the right and left atrial sides, with gradual improvement of impulse conduction.
After the procedure, we observed a persistence of only first degree AVB (PQ interval 260 msec) and a complete regression of symptoms, persistent at 6-month follow-up.
Conclusions.
A strategy of modulation of ganglionated plexi by endocardial ablation is conceivable for the treatment of pathological conditions due to parasympathetic hyperactivity.
Patients with functional atrioventricular block (FAVB), even without organic damage to the conduction system, often present disabling symptoms with a significant reduction in quality of life. Treatment with drugs and/or pacemakers has given poor results; pacemaker implantation is not well accepted and is accompanied by significant psychological discomfort, as well as carrying a risk of infection and long-term ventricular desynchronization. The absence of an organic disease as well as a presumed benign course of the disease make the decision more difficult.
Current guidelines recommend the implantation of a definitive pacemaker in patients with paroxysmal or permanent third degree AVB, regardless of symptoms. Although not yet included in current guidelines, the CNA procedure could be used in the future to treat AV node dysfunctions in young subjects with a dominant functional component.
