https://doi.org/10.1007/s00392-024-02526-y
1Herz- und Diabeteszentrum NRW Klinik für Elektrophysiologie/ Rhythmologie Bad Oeynhausen, Deutschland; 2Herz- und Diabeteszentrum NRW Allgemeine und Interventionelle Kardiologie/Angiologie Bad Oeynhausen, Deutschland; 3Herz- und Diabeteszentrum NRW Klinik für Thorax- und Kardiovaskularchirurgie Bad Oeynhausen, Deutschland
Background
Ventricular fibrillation (VF) is a life-threatening complication in ST-elevation myocardial infarction (STEMI) patients. Being the most frequent reason for out-of-hospital mortality in STEMI, even for in-hospital patients recurrent VF is associated with poor outcome. Novel radiofrequency-guided catheter ablation (RFCA) strategies combining myocardial substrate characterization, Purkinje and ventricular fibrillation (VF) mapping have emerged. Real-world data on the efficacy and safety of RFCA for VF following PCI in STEMI patients are scarce.
Objective
The aim of this prospective observational study was to analyze the acute and long-term procedural success, complications and mortality in STEMI-patients that underwent rescue RFCA due to recurrent VF following successful PCI of the culprit lesion.
Methods
A total of ten consecutive STEMI patients who underwent RFCA for reperfusion- associated VF between 2020-2024 were included in our study. Data on procedural parameters, acute and long-term success, complications and mortality were analyzed.
Results
A total of 10 patients (mean age 63.9±10.3 years, 80% male) presented with therapy-refractory VF 15.8±9.4 days after STEMI. Target vessel for primary PCI was the left ascending coronary artery (LAD) in all patients (n=10, 100%). Left ventricular ejection fraction (LVEF) was 28.8±10.2%. Due to recurrent VF-episodes cardiopulmonary resuscitation (CPR), multiple external defibrillations, sedation, use of antiarrhythmic drugs, mechanical respiration as well as temporary overdrive stimulation was applied in all patients and led to reduction but not suppression of VF episodes. Hemodynamic support (HS) was necessary in six patients (60%; Impella, n=1, 10%; ECMO, n=6, 60%). Restenosis or progression of the underlying coronary artery disease was ruled out by means of control coronary angiography. As a last therapeutic option, a rescue endocardial RFCA was performed. Procedure time was 123.1±22.7min; fluoroscopy time 3.9±1.5min; ablation time 35.3±8.8min. In all patients, VF originated from areas associated with the underlying septal substrate of the left ventricle (LV) including damaged Purkinje-network (Figure 1). Septal substrate modification targeting Purkinje-network from both anterior and posterior fascicle of the left bundle branch (LBB) resulted in acute elimination of VF in all patients (n=10, 100%). Concerning complication rates two patients (n=20%) developed a third-degree atrioventricular block. Implantable cardioverter defibrillator (ICD) (n=5, 50%) or cardiac resynchronization therapy device (CRT-D) (n=5, 50%) implantation was required in all patients. Two patients (20%) died in hospital due to stroke and sepsis. During a mean follow up of 12 months one patient developed VF-recurrence (n=1, 10%).
Conclusion
Targeting the Purkinje-network during septal substrate modification of LV in a high-risk-cohort of VF following LAD-STEMI seems to be an effective therapeutic option in these selected patient cohort. Procedure associated complication rates and recurrence rates in midterm follow up were low. Further studies are needed to validate these initial observations.