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Catheter-Induced Left Main Coronary Artery Dissection Resulting in Abrupt Closure and Cardiac Arrest: Successful Stenting during
J INVASIVE CARDIOL 2007;19:E93-E95 Left main coronary artery (LMCA) dissection is a rare but potentially life-threatening complication of percutaneous coronary intervention (PCI). LMCA dissection is the harbinger of catastrophic vessel closure. It can be precipitated by the manipulation of interventional hardware in the LMCA ostium. Sharp angulation at the LMCA-LAD (left anterior descending artery) junction appears to be a risk factor for LMCA dissections.1 The usual management of LMCA injury is coronary artery bypass grafting surgery (CABG); however, bailout stenting has also been shown to be safe and feasible, and may be life-saving in cases of acute LMCA occlusion.2 We present here a case of a guide catheter-induced LMCA dissection that resulted in abrupt closure and cardiac arrest and subsequent successful stent implantation during cardiopulmonary resuscitation (CPR). Case Report. A 70-year-old female with hypertension, diabetes mellitus, and a 2-month history of exertional angina presented to the emergency department with long-lasting, severe retrosternal chest pain. Electrocardiography demonstrated ST-segment elevation in the anterior leads consistent with acute anterior myocardial infarction (MI). Thus, t-PA (tissue plasminogen activator) was administered 5 hours after the patient first experienced the pain. On the third day of her admission, coronary angiography was performed due to post-MI angina. Coronary angiography showed a mild stenosis at the mid-portion of a nondominant right coronary artery. There was severe stenosis at the proximal LAD (Figure 1). The decision was made to proceed with an intervention on the LAD. First, a 6 Fr left Judkins guide catheter (JL4) (Medtronic, Inc., Minneapolis, Minnesota) was used in an attempt to cannulate the LMCA, but due to high takeoff, the catheter could not be engaged coaxially. Consequently, a 6 Fr left Amplatz (AL2) guide catheter (Medtronic) was used, and after engaging, angiography revealed staining in the body of the LMCA with TIMI (thrombosis in myocardial infarction) 0 flow distally. The patient developed cardiopulmonary arrest within seconds and CPR was initiated with endotracheal intubation and manual chest compression. While resuscitating the patient, the AL2 guide catheter was removed and a 6 Fr FL5 guide catheter (Medtronic) was engaged in the LMCA. A floppy guidewire (Asahi Intecc, Japan) was crossed to the LMCA and the circumflex (Cx) artery (Figure 2), and a 22 x 4 mm bare-metal stent (Gendyl, Blue Medical, The Netherlands) was implanted in the LMCA and proximal Cx. Angiography demonstrated visualization of the Cx artery, but TIMI 0 flow to the LAD (Figure 3). Multiple episodes of ventricular fibrillation requiring repeated defibrillation (total of 18) occurred, which reverted to asystole again after shocks were administered. Amiodarone was administered. We attempted to cross to the LAD with an intermediate guidewire (Asahi Intecc, Japan) through the stent struts while manual cardiac massage was ongoing. After successfully crossing the guidewire to the LAD, the angiogram revealed TIMI 1–2 flow to the LAD, and subsequent defibrillation reverted to sinus rhythm after 45 minutes of CPR. An intra-aortic balloon pump (IABP) was immediately placed. Stent struts were dilated with a 3 x 15 mm balloon (Troya, Nemed, Turkey) at 8 atm, and a 2.75 x 25 mm stent (Aachen Flex Force, Germany) was implanted in the proximal LAD (Figure 4). Final injection revealed brisk TIMI 3 flow (Figure 5) and the patient was transferred to the coronary care unit. She was extubated and had the IABP removed within 24 hours. She developed nonoliguric renal failure with a maximum creatinine level of 4.6 mg/dl, which completely resolved with intravenous hydration. She was discharged on postoperative day-14. At her 6-month follow up she was free of angina. Discussion. Catheter-induced LMCA dissection is an uncommon but devastating complication of coronary angiography and percutaneous coronary intervention.3 The incidence of iatrogenic LMCA dissections is 0.02–0.035%.7,8 Risk factors associated with this complication are calcification of the LMCA, atherosclerotic disease of the left main stem, and anatomical distortion such as sharp angulation at the LMCA-LAD junction.1,9 The etiology of LMCA dissections can be classified as: (1) iatrogenic;4 (2) spontaneous;5 and (3) a complication of aortic root dissection.6 Extensive dissection of the coronary artery induced by a mechanical device may precipitate abrupt vessel closure. The management of left main dissections can be conservative, percutaneous intervention, or bypass surgery.2,10–12 Since the natural history of left main dissections are not well documented and largely unknown, treatment should be individualized on a case-by-case basis. Alfonso et al10 suggested watchful waiting for hemodynamically stable patients with a low-grade dissection. The presence of hemodynamic instability is a clear indication for intervention. Aortic involvement of 40 mm or more from the coronary ostium was considered a clear indication for surgical intervention.13 Lee at al2 reported that in a small number of patients with catheter-induced LMCA dissections, bailout stenting was safe and feasible. In our case, an acute coronary occlusion developed at the LMCA after engaging an Amplatz (AL2) guide catheter, which resulted in cardiopulmonary arrest. The unique features of this report are the successful bailout stenting of the LMCA during the 45-minute long CPR period, and the patient’s complete recovery. In conclusion, catheter-induced LMCA dissections are rare, but do occur. Emergency bailout stenting could be life-saving.
