Acute Hemodynamic Decompensation During Catheter Ablation of Scar-Related Ventricular Tachycardia

Abstract

R adiofrequency catheter ablation (RFCA) has an established therapeutic role in managing recurrent drug-refractory scar-related ventricular tachycardia (VT). 1 Owing to the complex substrate, concomitant heart failure, and associated comorbidities, patients undergoing catheter ablation of scarrelated VT experience significant morbidity and mortality rates. 2,3 In these patients, use of anesthesia, sustained hypotension as a result of spontaneous or induced VT, and fluid overload might contribute to periprocedural acute hemodynamic decompensation (AHD) requiring advanced hemodynamic support or procedure discontinuation. 4,5 Thus far, no data are available on the prevalence, predictors, and clinical significance of periprocedural AHD during catheter ablation of scarrelated VT. The proper identification of patients at high risk of periprocedural AHD would also have important implications for procedural planning because it would allow anticipation of the need for mechanical hemodynamic support. In this study, we evaluated the incidence and clinical predictors of periprocedural AHD during RFCA of scar-related VT and assessed its effect on mortality. MethodsThe study cohort consisted of consecutive patients who underwent RFCA of scar-related VT in the setting of ischemic or nonischemic cardiomyopathy at the Hospital of the University of Pennsylvania between January 2010 and December 2011. Patients with idiopathic VT and those with congenital heart disease were excluded. Whenever possible, antiarrhythmic drugs were discontinued for ≥4 half-lives before the procedure. Patients who were on chronic therapy with β-blockers or inhibitors of the renin-angiotensin-aldosterone system routinely held the medications the morning of the procedure (last dose administered the night before). Before the procedure, all patients © 2014 American Heart Association, Inc. P=0.004). At 21±7 months follow-up, the mortality rate was higher in the AHD group compared with the rest of the population (50% versus 11%, log-rank P<0.001). Conclusions-AHD occurs in 11% of patients undergoing radiofrequency catheter ablation of scar-related VT and is associated with increased risk of mortality over follow-up. AHD may be predicted by clinical factors, including advanced age, ischemic cardiomyopathy, more severe heart failure status (New York Heart Association class III/IV, lower ejection fraction), associated comorbidities (diabetes mellitus and chronic obstructive pulmonary disease), presentation with VT storm, and use of general anesthesia. (Circ Arrhythm Electrophysiol. 2015;8:68-75.

Prophylactic mechanical hemodynamic support for catheter ablation of VT: locking the barn door before the horse has bolted

“…1). The PAINESD risk score has been developed by the University of Pennsylvania group in an observational study including 193 consecutive patients undergoing catheter ablation of VT in the setting of structural heart disease [4]. Similar to the findings by Mathuria et al, periprocedural AHD requiring emergent placement of mechanical support devices and/or premature procedure discontinuation was found to have a strong negative prognostic impact, with an up to 50% mortality after an average follow-up of 21 ± 7 months.…”

“…The study endpoint was maintenance of a target mean arterial pressure (MAP) of 70-80 mmHg. With ventricular pacing at 200 bpm, no difference in mean arterial pressure was observed between the three MHS systems; however, with ventricular pacing at [4] 300 bpm and during sustained VF, only ECMO support was able to maintain the target MAP, with the lowest efficacy being observed with the Impella TM device [8]. Therefore, whether the results reported by Mathuria et al can be generalized also to patients undergoing VA-ECMO support warrant further investigation.…”

“…In these subjects, the competing risks associated with the concomitant presence of advanced heart failure syndromes and high burden of associated comorbidities pose substantial periprocedural and post-procedural management challenges [2,3]. In particular, the occurrence of periprocedural acute hemodynamic decompensation (AHD) is a major concern due to its significant association with post-procedural mortality [4]. Each aspect of a VT ablation procedure including induction of anesthesia, programmed ventricular stimulation, presence of spontaneous, and/or mechanically induced VT attempts at pace termination or needs for electrical cardioversions, and fluid overload during mapping and ablation incurs in a potential risk of precipitating AHD resulting in severe end-organ (e.g.…”

“…The predictors of AHD that were incorporated in the PAINESD risk score included age, diabetes, ischemic cardiomyopathy, reduced left ventricular ejection fraction, chronic obstructive pulmonary disease (COPD), presentation with VT storm, and NYHA functional class III/IV. An additional variable that was also found to be associated with increased risk of AHD was the use of general anesthesia [4]. …”

“…The ventricular unloading effect with P-LVAD may play a crucial role also in patients with large substrates undergoing a purely substrate-based ablation approach. In these patients, prolonged procedural (and anesthesia) times due to the necessity for complete substrate ablation and the resulting periprocedural fluid overload may precipitate AHD [4].…”