Impact of sedation vs. general anaesthesia on percutaneous epicardial access safety and procedural outcomes

Dexmedetomidine for sedation during epicardial ablation for ventricular tachycardia: a single-center experience

BACKGROUND

Epicardial approach to ventricular tachycardia (VT) ablation is mainly performed under general anesthesia (GA). Although catheter manipulation and ablation in the epicardial space could be painful, GA lowers blood pressure and may interfere with arrhythmia induction and mapping, and the use of muscle relaxants precludes identification of the phrenic nerve (PN). Moreover, an anesthesiologist's presence is required during GA for the whole procedure, which may not always be possible. Therefore, we evaluated the feasibility and safety of epicardial VT ablations performed under conscious sedation using dexmedetomidine in our center.

METHODS

Between January 2018 and January 2022, all patients who underwent epicardial VT ablation under continuous dexmedetomidine infusion were prospectively included in the study. All patients received premedication 30 min before the epicardial puncture with paracetamol (acetaminophen 10 mg/ml) 1000 mg and ketorolac 30 mg. Sedation protocol included an intravenous bolus of midazolam hydrochloride (0.03-0.05 mg/kg) followed by continuous infusion of dexmedetomidine (0.2-0.7 mcg/kg/h). In addition, an intravenous fentanyl citrate bolus (0.7-1.4 mcg/kg) was given for short-term analgesia, followed by a second dose repeated after 30 to 45 min. Sedation-related complications were defined in case of respiratory failure, severe hypotension, and bradycardia requiring treatment.

RESULTS

Sixty-nine patients underwent epicardial or endo-epi VT ablation under conscious sedation and were included in the analysis. The mean age was 65.4 ± 12.1 years; forty-six patients were males (66.6%). All patients had drug-refractory recurrent VT. Forty-seven patients (68.1%) had non-ischemic cardiomyopathy (NICM), 13 patients (18.9%) had ischemic-cardiomyopathy (ICM), and 9 patients (13%) had myocarditis. Standard percutaneous sub-xiphoid access was attempted in all patients. Non-inducibility of any VT was achieved in 82.6% (9/9 myocarditis, 10/13 ICM, 38/47 NICM, n = 57/69 patients), inducibility of non-clinical VT in 13% (3/13 ICM, 6/38 NICM, n = 9/69 patients), and failure in 4.3% (3/38 NICM, n = 3/69 patients). Although we observed procedural-related complications in five patients (7.2%), one transient PN palsy, two pericarditis, and two vascular complications, those were not related to the conscious sedation protocol. No respiratory failure, severe hypotension, or bradycardia requiring treatment has been observed among the patients.

CONCLUSIONS

Prompt availability of anesthesiology support remains crucial for complex procedures such as epicardial VT ablation. Continuous infusion of dexmedetomidine and administration of midazolam and fentanyl seem to be a safe and effective sedation protocol in patients undergoing epicardial VT ablation.

The effect of anesthesia depth on radiofrequency catheter ablation of ventricular tachycardia: a retrospective study

BACKGROUND

Radiofrequency catheter ablation (RFCA) as a safe and effective method has been widely used in ventricular tachycardia (VT) patients, and with which anesthesiologists frequently manage their perioperative care. The aim of this study was to investigate the effects of different anesthetic depths on perioperative RFCA and recurrence in patients who with intractable VT and could not tolerate an awake procedure.

METHODS

We reviewed electronic medical records of patients with VT who underwent RFCA by general anesthesia from January 2014 to March 2019. According to intraoperative VT induction, they were divided into two groups: non-inducible group (group N) and inducible group (group I). We constructed several multivariable regression models, in which covariates included patient characteristics, comorbidities, protopathy and bispectral index (BIS) value.

RESULTS

One hundred one patients were analyzed. Twenty-nine patients (28.7%) experienced VT no induction, and 26 patients (25.7%) relapsed within 1 year. Compared with group I, the proportion of patients with arrhythmogenic right ventricular cardiomyopathy in group N were higher (P < 0.05), and the recurrence rate of VT was significantly higher (51.7% vs 15.3%) (P < 0.05). The BIS value in group N was significantly lower (P < 0.01), in addition, the BIS < 40 was associated with elevated odds of VT no induction compared with a BIS > 50 (odds ratio, 6.92; 95% confidence interval, 1.47-32.56; P = 0.01). VT no induction was an independent predictor of recurrence after RFCA (odds ratio, 5.01; 95% confidence interval, 1.88-13.83; P < 0.01).

CONCLUSION

Lower BIS value during VT induction in RFCA operation was associated with high risk of VT no induction, which affects postoperative outcomes. We proposed that appropriate depth of anesthesia should be maintained during the process of VT induction.

Applicability of the PAINESD risk score for 30-day mortality prediction post ventricular tachycardia catheter ablation in Chagas disease

PURPOSE

The PAINESD risk score was developed in 2015 as a tool to stratify the risk of acute hemodynamic decompensation during ventricular tachycardia (VT) ablation in structural heart disease patients and further then used for post procedure 30-day mortality prediction. The original cohort however did not include Chagas disease (ChD) patients. We aim to evaluate the relevance of the score in a ChD population.

METHODS

The PAINESD risk score gives weighted values for specific characteristics (chronic obstructive pulmonary disease, age > 60 years, ischemic cardiomyopathy, New York Heart Association [NYHA] functional class 3 or 4, ejection fraction less than 25%, VT storm, and diabetes). The score was applied in a retrospective cohort of ChD VT ablations in a single tertiary center in Brazil. Data were collected by VT study reports and patient record analysis at baseline and on follow-up.

RESULTS

Between January 2013 and December 2018, 157 VT catheter ablation procedures in 121 ChD patients were analyzed. Overall, 30-day mortality was 9.0%. Multivariate analysis correlated NYHA functional class (HR 1.78, 95% CI 1.03-3.08, P 0.038) and the need for urgent surgery (HR 31.5, 95% CI 5.38-184.98, P < 0.001), as well as a tendency for VT storm at presentation (HR 2.72, 95% CI 0.87-8.50, P 0.084) as risk factors for the primary endpoint. The median PAINESD risk score in this population was 3 (3-8). The area under the receiver operating characteristic (ROC) curve was 0.64 (95% CI 0.479-0.814).

CONCLUSIONS

The PAINESD risk score did not perform well in predicting 30-day mortality in ChD patients. Pre-procedure NYHA functional class and the need for urgent surgery due to refractory pericardial bleeding were independently associated with increased 30-day mortality. Prospective studies are needed to take final conclusions in Chagas disease when using PAINESD score.

Hybrid Subxiphoid Perventricular Approach as an Alternative Access in Neonates and Small Children Undergoing Complex Congenital Heart Interventions

The hybrid subxiphoid perventricular approach provides direct access through the heart and may alleviate the technical limitations of complex percutaneous interventions particularly in infants with low body weight. We present the outcomes from a tertiary cardiology center using this approach. We performed a retrospective review of all patients less than 15 kg who underwent a hybrid perventricular approach via a small subxiphoid incision. Medical records were reviewed to obtain clinical, demographic and outcome data. Seventeen patients underwent 18 hybrid perventricular procedures using a subxiphoid approach. Median age at time of procedure was 4.6 months (IQR = 1.6 to 18 months) and median weight was 6.2 kgs (IQR = 3.4 to 8.6 kgs). Six patients underwent hybrid pulmonary valve replacement (PVR), 5 patients underwent pulmonary outflow stenting, and 5 infants underwent hybrid ventricular septal defect (VSD) device closure. One patient with a single ventricle who did not tolerate a percutaneous approach underwent left pulmonary artery (LPA) stenting for severe LPA coarctation with subsequent right ventricular outflow tract (RVOT) stenting. One further patient underwent implantation of a larger diameter stent for pulmonary artery bifurcation stenosis. Procedure success rate was 89% with two of the VSD cases reverted to open surgical repair. There were no intra-procedural complications; however, one patient died within 72 h. Minor adverse events occurred in 2 patients including a wound infection in one patient with an immunodeficiency syndrome. Hybrid subxiphoid perventricular approach provides an excellent alternative access to the heart especially in low birth weight infants to prevent hemodynamic instability or in small children requiring large delivery sheaths.

Epicardial Ablation Complications

The percutaneous epicardial approach has become an adjunctive tool for electrophysiologists to treat disparate cardiac arrhythmias, including accessory pathways, atrial tachycardia, and particularly ventricular tachycardia. This novel technique prompted a strong impulse to perform epicardial access as an alternative strategy for pacing and defibrillation, left atrial appendage exclusion, heart failure with preserved ejection fraction, and genetically engineered tissue delivery. However, because of the incremental risk of major complications compared with stand-alone endocardial ablation, it is still practiced in a limited number of highly experienced centers across the world.