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The DDDR closed loop stimulation for the prevention of vasovagal syncope: results from the INVASY prospective
E Occhetta1, M Bortnik, C Vassanelli
1Divisione Clinicizzata di Cardiologia, Facolta' di Medicina e Chirurgia di Novara, Universita' degli Studi del Piemonte Orientale, Novara, Italy. cardio l@maggioreosp.novara.it
Insights
Closed Loop Stimulation (CLS) pacing effectively prevented vasovagal syncope in most patients. This innovative pacemaker technology shows promise for managing recurrent fainting episodes.
Area of Science:
- Cardiology
- Biomedical Engineering
Background:
- Vasovagal syncope affects ventricular myocardium contraction dynamics.
- Closed Loop Stimulation (CLS) pacing offers novel heart rate modulation.
- The INOS(2) CLS pacemaker optimizes heart rate using myocardial contraction dynamics via intracardiac impedance.
Purpose of the Study:
- Evaluate long-term clinical outcomes of DDDR-CLS pacing in patients with recurrent vasovagal syncope.
- Assess the acute precipitation of vasovagal fainting using DDDR-CLS mode versus DDD mode during head-up tilt testing.
Main Methods:
- A prospective registry study involved 34 patients with recurrent vasovagal syncope.
- Patients were implanted with INOS(2) DDDR CLS pacemakers.
- Clinical outcomes and syncope recurrence were monitored over 12-50 months.
Main Results:
- 30 out of 34 patients remained syncope-free during follow-up.
- One patient experienced palpitations resolved by reprogramming.
- Two patients had presyncope, and one had recurrent syncope possibly due to atrial fibrillation.
Conclusions:
- DDDR-CLS pacing demonstrates a beneficial effect in preventing vasovagal syncope.
- Further research is needed to fully understand the preventive mechanisms.
- A new randomized trial (INVASY) is underway to confirm these findings in a larger cohort.
Background:
The contraction dynamics of the ventricular myocardium are affected before and during vasovagal fainting suggesting that the Closed Loop Stimulation (CLS) pacemaker could be useful for the treatment of these patients. CLS is a new concept of heart rate modulation in cardiac pacing. The pacemaker INOS(2) CLS (Biotronik, Germany) derives its information for heart rate optimization from myocardial contraction dynamics, by measuring right ventricular intracardiac impedance. The pacemaker becomes an integral part of the circulatory regulation and, therefore, reacts appropriately to different cardiovascular demands.
Methods:
In a prospective registry, 34 patients with a history of recurrent vasovagal syncopal events were implanted with INOS(2) DDDR CLS pacemakers. The aim of the study was to evaluate both long term clinical outcome, including the first recurrence of syncope, with DDDR-CLS pacing and acute precipitation of vasovagal fainting with DDDR-CLS mode compared with DDD during head up tilt testing.
Results:
During a follow up period of 12-50 months, 30 patients experienced no further syncopal events in daily life; 1 patient had no syncope but night palpitations, which were eliminated by pacemaker reprogramming; 2 patients had presyncopal episodes but not syncopes; 3 syncopal recurrences occurred in one patient in chronic atrial fibrillation, possibly not an ideal candidate for implantation.
Conclusions:
Further studies for detailed understanding of the preventive mechanism of DDDR-CLS pacing in vasovagal syncope are warranted. A randomized multicentre prospective new study (INotropy controlled pacing in VAsovagal SYncope: INVASY) is now in progress to confirm the beneficial effect of DDDR-CLS pacing in a larger group of patients with recurrent vasovagal syncope.
