Fernando M. Contreras-Valdes

Severity of esophageal injury predicts time to healing after radiofrequency catheter ablation for atrial fibrillation

BACKGROUND The delivery of radiofrequency (RF) energy to the posterior left atrium creates a risk of injury to the adjacent esophagus. Esophageal endoscopy (EGD) is used to screen patients at risk for esophageal thermal injury after RF ablation. OBJECTIVE The purpose of this study was to analyze the macroscopic features of the severity of esophageal injuries induced by RF ablation to the left atrium as seen by EGD and evaluate the association of these descriptions with the time elapsed until complete healing. METHODS This study analyzed 219 patients undergoing RF ablation for atrial fibrillation. Esophageal temperature probes were used during each ablation, and EGD was performed in cases with intraesophageal temperature ≥39°C. Repeat EGD was obtained at 10 days to evaluate for healing in all cases demonstrating esophageal injury. Serial endoscopies were repeated every 2 weeks until complete healing was documented. Lesions were classified according to severity as superficial or deep ulceration; size and shape were also noted. RESULTS We found 37.4% of patients (82 of 219) with esophageal intraluminal temperatures ≥39°C. Of these, 22 patients (27%) were identified with esophageal injury, with 68% being superficial ulcerations and 32% deep. On repeat EGD at 10 days, only 29% of deep ulcerations were healed, as compared with 87% of the superficial injuries (P = .0136). No difference in healing was found when analyzed for size or shape. CONCLUSIONS The macroscopic severity of esophageal lesions detected on endoscopy the day after RF ablation can predict the time to resolution, with severe, deep ulcerations requiring a longer time to heal.

Radiofrequency ablation annotation algorithm reduces the incidence of linear gaps and reconnection after pulmonary vein isolation

BACKGROUND A common mechanism of atrial fibrillation recurrence after catheter ablation is resumption of pulmonary vein (PV) conduction due to gaps in the ablation line. These gaps may go unrecognized owing to inadequate ablation lesion annotation. OBJECTIVE To examine the utility of an automated radiofrequency (RF) ablation annotation algorithm for the detection and treatment of ablation gaps during pulmonary vein isolation (PVI). METHODS Eighty-four patients with paroxysmal atrial fibrillation underwent PVI. In 42 patients (group A), RF ablation was guided by an automated algorithm with predefined criteria of catheter stability range of motion ≤2 mm and impedance decrease ≥5% for individual ablation applications. In 42 control patients (group B), ablation was guided by the operator. Successful PVI, conduction recovery, and dormant conduction with adenosine were compared between the groups. RESULTS Ipsilateral PVI at the completion of the initial anatomical line was obtained in 90.5% of group A patients (76 of 84 ipsilateral pairs of PVs) but only in 66.7% of group B patients (56 of 84 ipsilateral pairs of PVs) (P = .0001). Ineffective energy delivery was detected in 23% (1005 of 4362) of group A applications but only in 9% (368 of 4071) of group B applications (P = .0001). The frequency of conduction recovery was lower in group A than in group B (5.9% vs 25%; P = .001). Arrhythmia-free survival at 6 months trended higher in group A (38 of 42 [90%]) than in group B (32 of 42 [76%]; P = .07). CONCLUSION Automated ablation lesion annotation provides real-time feedback of RF ablation that may improve effective energy delivery.

Atrial fibrillation ablation in patients with hypertrophic cardiomyopathy: long-term outcomes and clinical predictors.

Atrial fibrillation (AF) is common in patients with hypertrophic cardiomyopathy (HCM), present in 20% to 25% [(1)][1]. Radiofrequency (RF) ablation is a safe and effective option for selected patients with symptomatic AF. However, its efficacy in patients with HCM has been less studied. AF in this

Incidence and risk factors for symptomatic heart failure after catheter ablation of atrial fibrillation and atrial flutter

AIMS To determine the incidence and risk factors for development of symptomatic heart failure (HF) following catheter ablation for atrial fibrillation (AF) and atrial flutter. METHODS AND RESULTS We prospectively enrolled consecutive patients undergoing pulmonary vein isolation (PVI) or cavotricuspid isthmus (CTI) ablation between November 2013 and June 2014. Post-discharge symptoms were assessed via telephone follow-up and clinic visits. The primary outcome was symptomatic HF requiring treatment with new/increased diuretic dosing. Secondary outcomes were prolonged index hospitalization and readmission for HF ≤30 days. Univariate and multivariable logistic regressions were used to assess the relationship between patient/procedural characteristic and post-ablation HF. Among 111 PVI patients [median age 62.0 years; left ventricular ejection fraction (LVEF) 55%], 29 patients (26.1%) developed symptomatic HF, 6 patients (5.4%) required prolonged index hospitalization, and 8 patients (7.2%) were readmitted for HF. In univariate analyses, persistent AF [odds ratio (OR) 2.97, P = 0.02], AF at start of the procedure (OR 2.99, P = 0.01), additional ablation lines (OR 11.07, P < 0.0001), and final left atrial pressure (OR 1.10 per 1 mmHg increase, P = 0.02) were associated with HF development. Peri-procedural diuresis, net fluid balance, and LVEF were not correlated. In multivariable analyses, only additional ablation lines (ORadj 9.17, P = 0.007) were independently associated with post-ablation HF. Six patients (16.7%) developed HF after CTI ablation. CONCLUSION A 26.1% of patients undergoing PVI and 16.7% of patients undergoing CTI ablation developed symptomatic HF when prospectively and uniformly assessed. 12.6% of patients experienced prolonged index hospitalizations or readmission for management of HF within 1 week after PVI. Improved understanding of risk factors for post-ablation HF may be critical in developing strategies to address during AF ablation.

How we implemented a resident-led medical simulation curriculum in a large internal medicine residency program

Abstract Mannequin-based simulation in graduate medical education has gained widespread acceptance. Its use in non-procedural training within internal medicine (IM) remains scant, possibly due to the logistical barriers to implementation of simulation curricula in large residency programs. We report the Massachusetts General Hospital Department of Medicine’s scale-up of a voluntary pilot program to a mandatory longitudinal simulation curriculum in a large IM residency program (n = 54). We utilized an eight-case curriculum implemented over the first four months of the academic year. An intensive care unit curriculum was piloted in the spring. In order to administer a comprehensive curriculum in a large residency program where faculty resources are limited, thirty second-year and third-year residents served as session facilitators and two senior residents served as chairpersons of the program. Post-session anonymous survey revealed high learner satisfaction scores for the mandatory program, similar to those of the voluntary pilot program. Most interns believed the sessions should continue to be mandatory. Utilizing residents as volunteer facilitators and program leaders allowed the implementation of a well-received mandatory simulation program in a large IM residency program and facilitated program sustainability.

High-power and short-duration ablation for pulmonary vein isolation: Safety, efficacy, and long-term durability

PV reconnection is often the result of catheter instability and tissue edema. High‐power short‐duration (HP‐SD) ablation strategies have been shown to improve atrial linear continuity in acute pre‐clinical models. This study compares the safety, efficacy, and long‐term durability of HP‐SD ablation with conventional ablation.

“Frog Sign” in Atrioventricular Nodal Reentrant Tachycardia

An 83-year-old man was evaluated for frequent palpitations. During an episode, examination of the neck revealed rapid and regular pulsations with bulging of the internal jugular veins, shown in a video. A 12-lead electrocardiogram showed a regular, narrow-complex tachycardia.

Should Adenosine Test Be Performed Systematically At The End Of Atrial Fibrillation Ablation Procedure

Pulmonary vein (PV) reconnection is a major limitation of atrial fibrillation (AF) ablation and is a significant contributor for arrhythmia recurrence, particularly in patients with paroxysmal AF. Recent technological advances, including the use of steerable sheaths and force sensing catheters resulted in reduced incidence of PV reconnection; however its incidence remains unacceptably high. Additional efforts to reduce pulmonary vein reconnection include the use adenosine to detect dormant PV to left atrial (LA) electrical conduction as well as identification of non-PV triggers. While this strategy is associated with an increased detection rate of reconnection that can be further targeted with ablation, its effect on long-term arrhythmia control is controversial. Still, adenosine-induced PV reconnection appears to be an independent predictor of arrhythmia recurrence despite additional ablation. We favor its use in patients with paroxysmal AF as an additional step for risk stratification and prediction of arrhythmia recurrence.

Esophageal temperature monitoring during AF ablation: multi-sensor or single-sensor probe? Response to letter to the editor.

Thank you for giving us the opportunity to respond to Dr. Feld’s valid concerns.1 As stated in the article, the ablation strategy was altered when heating was encountered along the posterior wall.2 Specifically, in addition to limiting power to 25 Watts and duration to 30 seconds, the catheter was moved away from the esophagus along with a further decrease in power and/or duration of ablation lesions. We believe the need to move further away from the esophagus given the increased temperature rises may have contributed the increased ablation time in the multisensor probe group. Although it is reasonable to assume that increased ablation time would lead to more injury, this was not found in 2 prior studies investigating patient and procedural characteristics between those with esophageal injury and those without.3,4 Furthermore, as shown in Table 3 of our article, there was no significant difference in total energy applied in those with injury and those without injury among those who had an esophageal endoscopy (EGD) performed in either temperature probe cohort. Feld et al. also raise concerns regarding the introduction of selection bias because EGDs were only performed on patients with a temperature rise ≥39 ◦C. We too raised this as a limitation of our study in the article. This critique is based on the belief that the multisensor probe has greater sensitivity; however, that assumes the multisensor probe itself did not play any role in the development of increased temperature rises within the esophagus and potential injury. Our study did not evaluate the sensitivity of the temperature probes to detect injury as EGDs were not performed in all patients; therefore, it cannot be assumed the multisensor probe is more sensitive. In our article, we compared the percentage of esophageal injury in only those with EGDs performed rather than comparing the percentage of injury within the respective cohorts as a whole. There is the potential that some injury was missed; however, it is impossible to know if a higher percentage of lesions would have been found in those without a temperature rise in the single-sensor group versus the multisensor group. We agree with Feld et al. that the multisensor probe is usually enface fluoroscopically rather than in an anteroposterior configuration. However, we disagree that only an anteroposterior configuration is necessary to affect the relationship between the esophagus and the left atrium (LA). The multisensor probe is of much greater width (18 mm vs 3 mm). The esophagus is mobile and can change configuration throughout the procedure, which may be a protective mechanism.5 We hypothesize that the greater width of the multisensor probe may create a more persistent increase in contact surface area of LA to esophagus. We did not study the difference in material or design of the probes themselves, as was studied by Deneke et al. with a different catheter