Safety of Same Day Discharge after Atrial Fibrillation Ablation.

INTRODUCTION: It is routine practice to observe patients (pts) overnight in the hospital after atrial fibrillation (AF) ablation. We report single center experience comparing the rate of complications prior to and after implementing a strategy of same day discharge (SDD) following AF ablation. OBJECTIVE: To assess the safety of SDD after AF ablation. METHODS: We reviewed the charts of consecutive pts who underwent AF ablation between Jan 2005 to Dec 2015. Patients who were electively admitted to undergo AF ablation or left atrial flutter ablation (AFL) were included. Patients undergoing only right atrial flutter ablation and in-patients were excluded. In Sept 2012 SDD strategy was implemented. Complication rates were collected up to 3 months post ablation. Major complications were defined as death, pericardial tamponade, CVA, hematoma requiring intervention, pulmonary vein stenosis, diaphragmatic paralysis or atrioesophageal fistula formation. Minor complications were defined as hematoma not requiring intervention and procedure related readmissions. Comparisons were made using an intention to treat analysis. RESULTS: Group A (between Jan 2005 to Feb 2010) included 145 patients (87 males; 60.2 yrs mean age; 103 paroxysmal AF) who were observed overnight. Group B (between Mar 2010 to Dec 2015) included 426 patients (298 males; 62.3 yrs mean age; 247 paroxysmal AF) undergoing ablation following implementation of the SDD strategy. Patients in Group B were contacted by phone next day. In Group B, 51/426 (12%) pts were not discharged same day due to non-ablation related medical care (15/50 pts), ablation related complications (17/50 pts), pt preference (14/50 pts) and late cases (5/50 pts). Rate of total complications was more frequent in Group A (Group A 11.7% vs Group B 4.4%; p 0.026). Major complications happened in 2 pts in Group A and 6 pts in Group B. None of the major complications in Group B happened within 24 hrs of discharge. Only one pt in Group B had pericardial effusion drained 10 days post procedure. Most common minor complication in Group A was hematoma not requiring intervention and Group B was procedure related readmissions. CONCLUSIONS: Our data suggest that SDD after AF or AFL ablation can be safely implemented in majority of pts with similar outcomes as pts observed overnight.

Therapy From a Novel Substernal Lead: The ASD2 Study.

OBJECTIVES: The ASD2 (Acute Extravascular Defibrillation, Pacing, and Electrogram) study evaluated the ability to adequately sense, pace, and defibrillate patients with a novel implantable cardioverter-defibrillator (ICD) lead implanted in the substernal space. BACKGROUND: Subcutaneous ICDs are an alternative to a transvenous defibrillator system when transvenous implantation is not possible or desired. An alternative extravascular system placing a lead under the sternum has the potential to reduce defibrillation energy and the ability to deliver pacing therapies. METHODS: An investigational lead was inserted into the substernal space via a minimally invasive subxiphoid access, and a cutaneous defibrillation patch or subcutaneous active can emulator was placed on the left mid-axillary line. Pacing thresholds and extracardiac stimulation were evaluated. Up to 2 episodes of ventricular fibrillation were induced to test defibrillation efficacy. RESULTS: The substernal lead was implanted in 79 patients, with a median implantation time of 12.0 ± 9.0 min. Ventricular pacing was successful in at least 1 vector in 76 of 78 patients (97.4%), and 72 of 78 (92.3%) patients had capture in ≥1 vector with no extracardiac stimulation. A 30-J shock successfully terminated 104 of 128 episodes (81.3%) of ventricular fibrillation in 69 patients. There were 7 adverse events in 6 patients causally (n = 5) or possibly (n = 2) related to the ASD2 procedure. CONCLUSIONS: The ASD2 study demonstrated the ability to pace, sense, and defibrillate using a lead designed specifically for the substernal space.

Feasibility of extravascular pacing with a novel substernal electrode configuration: The Substernal Pacing Acute Clinical Evaluation study.

BACKGROUND: Subcutaneous implantable cardioverter-defibrillators provide an alternative to transvenous defibrillation but require higher shock outputs and offer no antitachycardia pacing. The Substernal Pacing Acute Clinical Evaluation (SPACE) study evaluated the feasibility of pacing from an extravascular substernal location. OBJECTIVES: The primary purpose of the SPACE study was to characterize pacing from the substernal space. Secondary objectives included evaluating extracardiac stimulation and recording electrograms. METHODS: The SPACE study prospectively evaluated the feasibility of pacing with a commercially available electrophysiology catheter acutely implanted in the substernal space via minimally invasive subxiphoid access. Pacing data were collected in ≥7 vectors using constant current stimulation up to 20 mA and pulse width up to 10 ms. RESULTS: Catheter placement was successful in all 26 patients who underwent the procedure, with a mean placement time of 11.7 ± 10.1 minutes. Eighteen patients (69%) had successful ventricular capture in ≥1 tested vector. The mean pacing threshold at a pulse width of 10 ms was 7.3 ± 4.2 mA across all vectors (5.8 ± 4.4 V). Failed capture was generally associated with suboptimal catheter placement or presumed air ingression. A low level of extracardiac stimulation was observed in 1 patient. The mean R-wave amplitude ranged from 2.98 to 4.11 mV in the unipolar configuration and from 0.83 to 3.95 mV in the bipolar configuration. CONCLUSION: The data from the SPACE study demonstrate that pacing is feasible from the extravascular substernal location. A substernal electrode configuration has the potential to provide pacing in a future extravascular device without need for intracardiac hardware placement.

Impact of emergency department management of atrial fibrillation on hospital charges.

INTRODUCTION: Emergency department (ED) cardioversion (EDCV) and discharge of patients with recent onset atrial fibrillation or atrial flutter (AF) has been shown to be a safe and effective management strategy. This study examines the impact of such aggressive ED management on hospital charges. METHODS: A random sample of 300 AF patients were identified from an ED electronic data base and screened for timing of onset of their symptoms. Patients were considered eligible for EDCV if either nursing or physician notes documented an onset of symptoms less than 48 hours prior to ED presentation and the patient was less than 85 years of age. An explicit chart review was then performed to determine patient management and disposition. Cardioversion attempts were defined as ED administration of procainamide, flecainide, propafenone, ibutilide, amiodarone or direct current cardioversion (DCCV). Total hospital charges for each patient were obtained from the hospital billing office. Differences across medians were analyzed utilizing through Wilcoxon rank sum tests and chi square. RESULTS: A total of 51 patients were included in the study. EDCV was attempted on 24 (47%) patients, 22 (92%) were successfully cardioverted to normal sinus rhythm (NSR). An additional 12 (23%) spontaneously converted to NSR. Twenty (91%) of those successfully cardioverted were discharged from the ED along with 4 (33%) of those spontaneously converting. Pharmacologic cardioverson was attempted in six patients and was successful in three (50%), one after failed DCCV attempt. Direct current cardioversion was attempted in 21 (88%) and was successful in 19 (90%), two after failed pharmacologic attempts. Median charges for patients cardioverted and discharged from the ED were $5,460 (IQR $4,677-$6,190). Median charges for admitted patients with no attempt at cardioversion were $23,202 (IQR $19,663-$46,877). Median charges for patients whose final ED rhythm was NSR were $5,641 (IQR $4,638-$12,339) while for those remaining inAF median charges were $30,299 (IQR $20,655 - $69,759). CONCLUSION: ED cardioversion of recent onset AF patients results in significant hospital savings.

Late angiographic follow-up in adults with initial angiographic normal or minimally narrowed coronary arteries.

We identified 46 patients with angiographically normal coronary arteries and 16 patients with minor irregularities (luminal narrowing < or =30%) who had repeat coronary angiograms obtained at our institution during the subsequent 15-year period. On follow-up angiograms, 19 of 46 (41%) in the normal coronary group and 13 of 16 (81%) in the minor lesion group showed progression of coronary artery disease (CAD). Five patients (11%) with no angiographic luminal CAD at the time of their baseline angiogram developed an acute myocardial infarction during the follow-up period. Patients in group 1 progressed from no vessels with angiographic lesions to a mean of 0.70 +/- 0.90 vessels diseased and a mean angiographic narrowing of 24 +/- 34% at the time of their follow-up angiograms, yielding a CAD progression rate of 2.6% luminal narrowing per year. Patients in group 2 had a mean progression of 0.69 +/- 0.79% of their vessels and a mean progression in their narrowing of 34 +/- 21%, yielding a CAD progression rate of 6.0% luminal narrowing per year. In conclusion, CAD can manifest late, or more likely, many patients with apparently normal coronary arteries have intimal CAD undetectable by angiography.