Real-world evidence demonstrates an appropriate atrial fibrillation population for hybrid convergent approach versus stand-alone cryoballoon ablation: A long-term safety and efficacy study.

INTRODUCTION: A hybrid convergent approach (endocardial and epicardial ablation) demonstrated superior effectiveness in a recent randomized study for long-standing persistent atrial fibrillation (LSPAF). Yet, there is a lack of real-world, long-term evidence as to which patients are best candidates for a hybrid convergent approach compared to standard endocardial cryoballoon pulmonary vein isolation (CB PVI). METHODS AND RESULTS: This single-center, retrospective analysis spanning from 2010 to 2015 compared two distinctly different atrial fibrillation (AF) cohorts; one treated with stand-alone cryoablation and one treated with a hybrid convergent approach. Baseline characteristics described candidates for each approach. The following criteria were utilized to determine CB PVI candidacy: (1) paroxysmal AF (PAF) (stage 3A) with failed class I/III antiarrhythmic drug (AAD) or (2) persistent/LSPAF (stage 3B/3C/3D) with failed class I/III AAD unwilling to undergo hybrid procedure. Selection criteria for the hybrid procedure included: (1) PAF refractory to both class I/III AAD and prior CB PVI (stage 3D) or (2) persistent/LSPAF (stage 3B/3C/3D) with failed class I/III AAD agreeable to hybrid procedure. Prior sternotomy was excluded. Serial electrocardiograms and continuous monitoring evaluated primary efficacy outcome of time-to-first recurrence of atrial arrhythmia after a 90-day blanking period. Secondary outcomes were procedure-related complications and AAD use (at discharge, 12, and 36 months). Kaplan-Meier methods evaluated arrhythmia recurrence. Of 276 patients, 197 (64.2 ± 10.6 years old; 66.5% male; 74.1% 3A-PAF; 18.3% 3B/3D-persistent AF; 1.0% 3C-LSPAF; 6.6% undetermined) underwent CB PVI and 79 (61.4 ± 8.1 years old; 83.5% male; 41.8% 3D-PAF; 45.5% 3B/3D-persistent AF; 12.7% 3C/3D-LSPAF) underwent hybrid procedure. Arrhythmia freedom through 36 months was 55.2% for CB PVI and 50.4% for hybrid (p = .32). Class I AAD utilization at discharge occurred in 38 (19.3%) patients in the CB PVI group and 5 (6.3%) patients in the hybrid group (p = .01). CB PVI class I AAD utilization at 12 months occurred in 14 (9.0) patients versus 0 patients for hybrid convergent (p = .004). Patients with one or more adverse event were as follows: two (1.0%) in the CB PVI group (both transient phrenic nerve palsy) and three (3.7%) in the hybrid group (two with significant bleeding and one with wound infection) (p = .14). CONCLUSION: This study demonstrated that patients with more complex forms of AF (3D-PAF or 3B/3C/3D-persistent/LSPAF) could be well managed with a convergent approach. In a real-world evaluation, outcomes match safety and efficacy thresholds achieved for patients with earlier, less complex AF etiologies treated by CB PVI alone.

Feasibility and accuracy of using mobile phone images of electrocardiograms to initiate the cardiac catheterization process.

We assessed the feasibility of interpreting the presence of ST-segment elevation myocardial infarction (STEMI) using ECGs captured and transmitted by mobile phones. Transmitted ECGs were interpreted by four independent and blinded physicians, who classified them as STEMI, non-STEMI or indeterminate. After 2-4 weeks the same physicians were given the original paper ECGs for interpretation. In total, 87 ECGs were randomly selected for review. The overall agreement between the digital image readings and the printed copy readings was 94%. Of the 87 patients, 65 (75%) had cardiac catheterization following a STEMI ECG and 22 (25%) did not receive cardiac catheterization. The accuracy of digital ECGs and printed ECGs when compared to the findings from cardiac catheterization was similar. Agreement in ECG interpretations between printed images and mobile phone images was excellent, and both had similar accuracy in activating the cardiac catheterization laboratory. Mobile phone transmission is an inexpensive method of evaluating ECG images sent from pre-hospital settings to the emergency department.

Atrial overdrive pacing and incidence of heart failure-related adverse events in permanently paced patients.

BACKGROUND: Atrial overdrive pacing algorithms may be effective in preventing or suppressing atrial fibrillation (AF). However, the maintenance of a heart rate incessantly faster than spontaneous could induce left ventricular (LV) dysfunction and promote heart failure (HF) on the long term. OBJECTIVE: This post hoc analysis examined the effects of a new overdrive algorithm on the incidence of HF-related adverse events in 411 patients enrolled in the ADOPT-A trial. MATERIALS AND METHODS: The AF Suppression algorithm was randomly programmed ON in 209 patients (treatment group) versus OFF in 202 patients (control group). The incidence of HF-related adverse events and HF-related deaths over a 6-month follow-up was compared between the two groups. Patients with versus without HF-related clinical events were also compared to each other within each group. RESULTS: There were eight HF-related adverse clinical events (3.8%) in the treatment group and 11 (5.4%) in the control group, including four HF-related deaths (1.9 vs. 2.0%) in each group during follow-up. Baseline NYHA functional class in patients with versus without HF-related adverse events was 1.4 +/- 0.5 versus 1.5 +/- 0.7 in the control, and 1.5 +/- 0.8 versus 1.5 +/- 0.6 in the treatment group. LV ejection fraction (EF) was 49 +/- 7% in patients with, versus 57 +/- 12% in patients without HF-related adverse events, in the control group, and 43 +/- 14% in patients with, versus 56 +/- 13% in patients without HF-related adverse events, in the treatment group. LVEF was lowest and similar in both groups among patients who died from HF (35 +/- 10% in the control and 38 +/- 27% in the treatment group). CONCLUSIONS: In ADOPT-A, HF-related clinical events and deaths were related to LV dysfunction and not to atrial pacing overdriven by the AF suppression algorithm.

Left ventricular-based cardiac stimulation post AV nodal ablation evaluation (the PAVE study).

BACKGROUND: Chronic right ventricular pacing has been reported to promote cardiac dyssynchrony. The PAVE trial prospectively compared chronic biventricular pacing to right ventricular pacing in patients undergoing ablation of the AV node for management of atrial fibrillation with rapid ventricular rates. METHODS AND RESULTS: One hundred and eighty-four patients requiring AV node ablation were randomized to receive a biventricular pacing system (n = 103) or a right ventricular pacing system (n = 81). The study endpoints were change in the 6-minute hallway walk test, quality of life, and left ventricular ejection fraction. Patient characteristics were similar (64% male; age: 69 +/- 10 years, ejection fraction: 0.46 +/- 0.16; 83%, NYHA Class II or III). At 6 months postablation, patients treated with cardiac resynchronization had a significant improvement in 6-minute walk distance, (31%) above baseline (82.9 +/- 94.7 m), compared to patients receiving right ventricular pacing, (24%) above baseline (61.2 +/- 90.0 m) (P = 0.04). There were no significant differences in the quality-of-life parameters. At 6 months postablation, the ejection fraction in the biventricular group (0.46 +/- 0.13) was significantly greater in comparison to patients receiving right ventricular pacing (0.41 +/- 0.13, P = 0.03). Patients with an ejection fraction

A new pacemaker algorithm for the treatment of atrial fibrillation: results of the Atrial Dynamic Overdrive Pacing Trial (ADOPT).

OBJECTIVES: The Atrial Dynamic Overdrive Pacing Trial (ADOPT) was a single blind, randomized, controlled study to evaluate the efficacy and safety of the atrial fibrillation (AF) Suppression Algorithm (St. Jude Medical Cardiac Rhythm Management Division, Sylmar, California) in patients with sick sinus syndrome and AF. BACKGROUND: This algorithm increases the pacing rate when the native rhythm emerges and periodically reduces the rate to search for intrinsic atrial activity. METHODS: Symptomatic AF burden (percentage of days during which symptomatic AF occurred) was the primary end point. Patients underwent pacemaker implantation, were randomized to DDDR with the algorithm on (treatment) or off (control), and were followed for six months. RESULTS: Baseline characteristics and antiarrhythmic drugs used were similar in both groups. The percentage of atrial pacing was higher in the treatment group (92.9% vs. 67.9%, p < 0.0001). The AF Suppression Algorithm reduced symptomatic AF burden by 25% (2.50% control vs. 1.87% treatment). Atrial fibrillation burden decreased progressively in both groups but was lower in the treatment group at each follow-up visit (one, three, and six months) (p = 0.005). Quality of life scores improved in both groups. The mean number of AF episodes (4.3 +/- 11.5 control vs. 3.2 +/- 8.6 treatment); total hospitalizations (17 control vs. 15 treatment); and incidence of complications, adverse events, and deaths were not statistically different between groups. CONCLUSIONS: The ADOPT demonstrated that overdrive atrial pacing with the AF Suppression Algorithm decreased symptomatic AF burden significantly in patients with sick sinus syndrome and AF. The decrease in relative AF burden was substantial (25%), although the absolute difference was small (2.50% control vs. 1.87% treatment).