[Show abstract][Hide abstract] ABSTRACT: Nonsurgical subxiphoid pericardial access may be useful in ventricular tachycardia ablation and other electrophysiologic procedures but has a risk of right ventricular puncture.
The purpose of this study was to identify a signature pressure frequency that would help identify the pericardial space and guide access.
The study consisted of 20 patients (8 women and 12 men; mean age 59.1 +/- 14.2 years; left ventricular ejection fraction 25.2% +/- 12.2%; failed 1.8 +/- 0.5 endocardial ablations; unresponsive to 2.0 +/- 1.0 antiarrhythmic drugs; 6 ischemic cardiomyopathy, 12 nonischemic cardiomyopathy, 2 normal heart; 4 previous sternotomy) undergoing epicardial ventricular tachycardia ablation. After pericardial access was obtained, a 10Fr long sheath was used to record pressure inside the pericardium and pleural space. Pressures were analyzed using a fast Fourier transform to identify dominant frequencies in each chamber.
Mean pressures in the pleural space and the pericardium were not different (7.7 +/- 1.9 mmHg vs 7.8 +/- 0.9 mmHg, respectively). However, the pericardial space in each patient demonstrated two frequency peaks that correlated with heart rate (1.16 +/- 0.21 Hz) and respiratory rate (0.20 +/- 0.01 Hz), whereas the pleural space in each patient had a single peak correlating with respiratory rate (0.20 +/- 0.01 Hz).
The pericardial space demonstrates a signature pressure frequency that is significantly different from the surrounding space. This difference may make minimally invasive subxiphoid pericardial access safer for nonsurgeons and may have important implications for electrophysiologic procedures.
Heart rhythm: the official journal of the Heart Rhythm Society 05/2010; 7(5):604-9. DOI:10.1016/j.hrthm.2010.01.011 · 5.08 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Catheter ablation of atrial fibrillation is currently guided by x-ray fluoroscopy. The associated radiation risk to patients and medical staff may be significant. We report an atrial fibrillation ablation technique using intracardiac echocardiography (ICE) and electroanatomic mapping without fluoroscopy.
Twenty-one patients with atrial fibrillation (age, 42 to 73 years; 14 male; 14 paroxysmal, 7 persistent; body mass index, 26 to 38) underwent ablation. A decapolar catheter was advanced through the left subclavian vein until stable coronary sinus electrograms appeared on all electrodes. Two 9F sheaths were advanced transfemorally over a guide wire to the right atrium. A rotational ICE catheter was advanced through a deflectable sheath. Double transseptal puncture was performed with ICE guidance and facilitated by electrocautery. A 3D MRI left atrial image was registered to the ostia of the pulmonary veins using ICE. Catheter ablation was performed using ICE and electroanatomic mapping navigation. In 19 cases, no fluoroscopy was used and the staff did not wear protective lead. In 2 cases, 2 to 16 minutes of fluoroscopy was used to assist transseptal puncture. Median procedure time was 208 (188 to 221) minutes; coronary sinus cannulation took 5 (2 to 26) minutes; double transseptal took 26 (17 to 40) minutes; left atrial ablation time was 103 (90 to 127) minutes. All patients underwent circumferential pulmonary vein ablation and 8 patients underwent additional left atrial ablation. There were no procedure-related complications.
Catheter ablation of atrial fibrillation without fluoroscopy is feasible and merits further attention. This technique may be especially helpful in preventing x-ray exposure in children, pregnant women, and obese patients undergoing left atrial ablation.