A 72-year-old woman with a mechanical bileaflet MV (St. Jude Medical, St. Paul, MN; 29 mm) underwent catheter ablation for AT. The patient had undergone MV replacement for mitral stenosis and regurgitation at the age of 43. During the operation, the maze procedure and left atrial appendage resection were added because of her previous history of AF. Ten years after surgery, several types of ATs appeared. Antiarrhythmic drugs failed to maintain her sinus rhythm, and repeated electrical cardioversions were required owing to worsening heart failure caused by ATs. Preoperative echocardiography showed that the bileaflet prosthetic function remained normal.
After intracardiac clots were excluded by transesophageal echocardiography, the procedure was performed under intravenous anesthesia. Three-dimensional electroanatomical mapping (CARTO 3, version 7; Biosense Webster, Diamond Bar, CA) using a multipolar catheter (PentaRay; Biosense Webster) and radiofrequency application using an ablation catheter (ThermoCool SmartTouch SF; Biosense Webster) were performed. PentaRay mapping demonstrated that induced ATs were macroreentry-associated, with the incision line in the right atrium, and radiofrequency applications were applied to create a complete conduction block across the critical isthmuses. Because we could not completely rule out the possibility that the clinical AT was originated from the left atrium (LA), transseptal access was achieved using a radiofrequency needle, a nonsteerable sheath (8.5F, SL0; St. Jude Medical, St. Paul, MN) was introduced, and LA mapping was performed using PentaRay. Despite careful mapping around the mechanical MV, 1 of the PentaRay spines suddenly became entrapped in the mechanical MV. Fluoroscopic images revealed that 1 of the PentaRay spines was entrapped between the disc and the orifice ring, and the cover of the spine was torn and connected to the catheter body only by the metal wire (Figure 1
A ). The ipsilateral disc was fixed in a closed position, and the patient’s vital signs were stable. An additional transseptal puncture was performed cephalad of the first puncture site, and the steerable sheath (Agilis Nxt; Abbott Laboratories, Abbott Park, IL) was inserted into the LA. We attempted to release the entrapped spine by advancing the ablation catheter toward the stuck disc with the support of the steerable sheath and pushing on the hinge portion of the disc with the catheter tip (Figure 1
B, Supplemental Video 1
). Although the stuck and closed disc was considerably opened, the deeply entrapped spine between the disc and the orifice ring was not released. Next, we advanced the shaft of the PentaRay catheter toward the left ventricle (Figure 1
C). Immediately thereafter, the entrapped catheter was extracted, but the wire was sheared off and the spine floated through the Valsalva sinus and strayed into the coronary artery (Figure 1
D, Supplemental Videos 2
). We promptly requested the cooperation of coronary intervention specialists. Coronary angiography via the right femoral artery showed that the spine was at the proximal segment of the left circumflex artery (LCx) (Figure 2
A and 2
B ). Activated clotting time was maintained at more than 300 seconds to prevent intracoronary thrombus formation owing to the torn spine. A guide catheter (LAUNCHER 8F, JL 4.0 SH; Medtronic, Tokyo, Japan) was engaged in the left coronary artery, and a guidewire for percutaneous coronary intervention (PCI; SION blue; ASAHI-INTECC, Seto, Japan) was crossed into the LCx segment with the spine. Although the guidewire was carefully manipulated, the spine moved easily into the peripheral LCx. We attempted to grasp the spine with a snare (ONE Snare 4 mm; MERITMEDICAL, Tokyo, Japan), but the originally attached microcatheter with the snare pushed the spine further into the distal LCx because it was difficult to advance the original snare system into the peripheral LCx on the PCI guidewire. Next, a 4.0 mm snare with a 1.8F PCI micro-guide catheter (Finecross MG; Terumo Corporation, Tokyo, Japan) was employed instead of the originally attached micro-catheter to advance the distal LCx on the guidewire smoothly and grasp the spine, which was successfully retrieved into the guide catheter (Figure 2
C and 2
D and Figure 3
). Final coronary angiography confirmed that there were no remnants in the coronary arteries. Fluoroscopic images showed no restriction of mechanical valve mobility.
A computerized tomography scan of the head and trunk was performed immediately postoperatively to determine whether any segment of the catheter or wires remained in the body. The scan showed no residual foreign material throughout the body and no findings suggestive of acute cerebral infarction or systemic embolism. A detailed physical examination confirmed the absence of obvious paralysis or other neurological abnormalities. Postoperatively, troponin T was mildly elevated from 0.007 ng/mL to 0.321 ng/mL, but serum creatine kinase remained in the normal range. Transthoracic echocardiography after the procedure revealed that there was no significant change from the preoperative period, including mechanical valve function. Fortunately, the patient remained free of AT/AF at the 3-month postprocedure outpatient visit.