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Discussion In the electrophysiology setting, increased pericardial effusion or tamponade risk is associated with left-sided arrhythmia ablations, biventricular pacemaker placements, and implantable cardioverter defibrillators. Incisional ATs occur frequently in patients with previous corrective surgeries for congenital heart defects and mitral valve disease, and often necessitate transseptal catheterization. Reported complication rates of 1% relate to aortic puncture or left/right atrial free wall perforation [3]. Puncture into the NCC can be recognized by contrast medium injection and changes in the pressure waveform. If this complication goes unrecognized and the sheath advances into the aortic root, surgical repair is usually mandated. However, in this case, we managed the patient conservatively without the need of surgical or percutaneous closure. We used a structured approach with pre-procedural identification of challenging anatomical substrates, and all diagnostic tools available to minimize complications. Fluoroscopic views of the catheter position should be at approximately 45° on the left anterior oblique (LAO) view and inferior and posterior to the pigtail catheter in the aortic root on the right anterior oblique (ROA) view. However, no specific angle in the RAO or LAO projections will be anatomically consistent in all patients, particularly those with prior heart surgery. This case highlights a rare catheter ablation complication with which all interventionists should be familiar. Our interesting finding was that there was no aorta–right atrial shunt after sheath removal from the NCC. It may relate to a “flap” that closed the connection between the from source and right atrium due to higher aortic pressure. Among patients who experience inadvertent aortic puncture as an acute complication of transeptal procedure, as well as experience surgical or percutaneous closure, those who do not have echocardiographic evidence of a large effusion respond well to initial stabilizing measures including fluids and vasopressors and thus, there appears to be a role for conservative management in such patients [4].
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Introduction Several studies have described an association between age or atrial size and atrial fibrosis [1,2], which may play a role in sinus node dysfunction. Although catheter ablation (CA) is a standard treatment for patients with atrial fibrillation (AF) [3], some patients, who are difficult to identify pre-procedurally, develop sinus node dysfunction after CA.
Case report A 39-year-old man underwent cardioversion for drug-refractory, symptomatic AF that had persisted for six months. The patient was scheduled for CA due to persistent AF burden, despite anti-arrhythmia therapy. Preoperative echocardiography revealed no structural heart disease, but revealed a small left atrium (LA; 33mm) and a sharp left atrial appendage peak flow velocity (92.8cm/s), without spontaneous echo contrast. AF was determined during initial CA to originate from multiple foci including the pulmonary veins, superior vena cava (SVC), posterior LA, and right atrium (RA) crista terminalis. Therefore, the SVC was electrically isolated, the other foci were focally ablated, and extensive circumferential pulmonary vein isolation was performed without any obvious complications. Linear ablation was not performed. The patient׳s clinical course following cardioversion is described in Table 1.
Discussion The specific reasons for the patient׳s sinus arrest are unknown. However, we speculate that the potential sinus node dysfunction might have progressed after the initial CA as a natural course in this patient׳s morphologically small heart, which is generally considered to be less remodeled. Masuda et al. [4] reported that PMI was required in five (5.0%) of 102 patients (mean age, 68 years) due to sick sinus syndrome following CA for chronic AF; in these patients, AF had persisted for approximately five years. Three of the patients underwent PMI for brady–tachycardia syndrome with recurrent AF, but two required PMI for sinus bradycardia following sinus rhythm restoration and CA [4]. Sinus node injury due to SVC isolation has been reported in 4.5% of cases, usually immediately after the procedure [5].