Left atrial appendage isolation during ablation in the interatrial septum: Rapid recognition by continuous monitoring of appendage electrograms.

Extensive atrial ablation in the setting of atrial fibrillation (AF) and atrial tachycardia (AT) can affect interatrial connections. A 76-year-old man with a history of tachycardia-induced cardiomyopathy and nine ablation procedures for AF/AT over 15 years presented with highly symptomatic recurrent AT. Previous ablation lesions included pulmonary vein isolation, left atrial posterior wall isolation, mitral isthmus line, cavotricuspid isthmus line, and the ablation of areas of fractionated electrograms. Electroanatomical mapping found the pulmonary veins and the left atrial posterior wall to be silent, as was the posterior interatrial septum and the mitral isthmus area. Activation mapping showed progression of electrograms in the left atrial appendage (LAA) from the septal aspect posteriorly, and in the coronary sinus from proximal to distal; implying the existence of a septal circuit, where extensive fractionation was noted. This was targeted, while monitoring conduction into the LAA using a multielectrode catheter. Ablation led to prompt termination of tachycardia and simultaneous LAA isolation. Immediate cessation of ablation led to recovery of conduction into LAA. Additional lesions in the interatrial septum were required to render the tachycardia noninducible, accompanied by temporary isolation of LAA. The ablation lesion sets employed while ablating AF and left AT can block many interatrial pathways, rendering conduction dependent on muscle bundles in the interatrial septum and, therefore, vulnerable to block by lesions in this area. LAA isolation has been associated with high incidence of LAA thrombus formation and stroke despite oral anticoagulation. Continuous observation of LAA electrograms during ablation can help to avoid this complication.

Femoral implantation and pull through as an adjunct to traditional methods in cardiac resynchronization therapy.

BACKGROUND: We have described the use of femoral access followed by pull through of the lead to a pectoral position to circumvent difficulty in implanting a left ventricular (LV) lead by standard methods. OBJECTIVE: The purpose of this study was to establish the effect of femoral implantation and pull through on the overall rate of success in percutaneous implantation of LV leads. METHODS: We collected data prospectively in all attempts at LV lead implantation from the time that we envisioned the femoral pull-through approach. RESULTS: In the 6 years to September 30, 2014, our group attempted to implant a new LV lead in 736 patients, including 16 who previously had failed attempts by other groups. A standard superior approach was successful in 726 of 731 patients (99.3%) in whom it was attempted. In 5 patients (0.7%), we failed to deliver a lead from a superior approach; in 5 of 16 patients, with previous failed attemtps (31%), we judged that those attempts had been exhaustive. In all 10 cases, LV lead placement was achieved from a femoral approach, with the procedure time being 186 ± 65 minutes. In the first case attempted, the pull through failed; the lead was tunneled to the pectoral generator. In 1 case, the coronary sinus was found to be occluded at the ostium: a transseptal approach was used with the subsequent pull through. No complication occurred. At 22.3 ± 18.5 months after the implantation, all systems implanted by a femoral approach continued to function. CONCLUSION: Used as an adjunct to standard methods, the femoral access and pull through method allows percutaneous LV lead placement in virtually all cases.

Survival of a highly toxic dose of caffeine.

A 27-year-old woman with a history of depression and previous overdose presented within 60 min of ingestion of 50 g of caffeine powder. Initially alert but hypotensive and tachycardic, the patient developed a broad complex tachycardia followed by a seizure and multiple ventricular fibrillation (VF) arrests. Following multiple defibrillations for VF, eight cycles of cardiopulmonary resuscitation and treatment with amiodarone, lidocaine, magnesium and potassium supplementation, the patient went to the intensive care unit (ICU). While there, the patient had further VF and required haemofiltration for a profound metabolic acidaemia with cardiac rhythm instability. She developed a postcardiac arrest systemic inflammatory response syndrome with episodes of acute pulmonary oedema, profound vasoplegia, hypothermia and coagulopathy. After 5 days in the ICU, the patient was stable enough to be transferred to the ward, with a persistent sinus tachycardia, and was discharged 3 days later with cardiology and psychiatry follow-up.

Successful ablation for atrioventricular nodal reentrant tachycardia in a patient with left atrial isomerism.

Left atrial isomerism (LAI) is characterized by the presence of two morphologically identical atria. It is commonly associated with conduction defects. We report a case of LAI presenting with highly symptomatic atrioventricular nodal reentrant tachycardia, which was cured by ablation.