title: Life-threatening ventricular arrhythmia due to silent coronary artery spasm: usefulness of I-123 metaiodobenzylguanidine scintigraphy for detecting coronary artery spasm in the era of automated external defibrillators: a case report.
abstract: BACKGROUND
  Cardiac arrhythmia is sometimes life-threatening, and automated external defibrillators are presently used in some countries. Coronary artery spasm is one of the primary causes of life-threatening arrhythmia. In general, chest symptoms are key indicators of possible coronary artery spasm; however, if chest symptoms are not present, clinicians may not suspect this disease. We encountered a patient who had recovered from ventricular fibrillation treated by using an automated external defibrillator, and silent coronary artery spasm was considered to be the cause of this life-threatening arrhythmia. In this case, I-123 metaiodobenzylguanidine scintigraphy was a useful screening tool for a silent coronary artery spasm.
  
  
  METHODS
  A 72-year-old Japanese man was transferred to our hospital after recovering from ventricular fibrillation treated by using an automated external defibrillator. He had never complained of chest symptoms previously. Decreased uptake of I-123 metaiodobenzylguanidine was observed in the inferolateral and anteroseptal walls of the left ventricle. A spasm provocation test of the coronary artery was performed, and silent coronary artery spasm was diagnosed as the underlying disease.
  
  
  CONCLUSIONS
  Non-invasive I-123 metaiodobenzylguanidine scintigraphy was a useful screening tool for silent coronary artery spasm as a possible cause of cardiopulmonary arrest in a patient with no chest symptoms.
authors: Division of Cardiovascular Medicine, Toyama Red Cross Hospital, 2-1-58 Ushijima-honmachi, Toyama, 930-0859, Japan. 3kaku@nyc.odn.ne.jp.
authors: Bunji
authors: B
authors: Kaku
authors: Division of Cardiovascular Medicine, Toyama Red Cross Hospital, 2-1-58 Ushijima-honmachi, Toyama, 930-0859, Japan. katuda@toyama-med.jrc.or.jp.
authors: Shoji
authors: S
authors: Katsuda
authors: Division of Cardiovascular Medicine, Toyama Red Cross Hospital, 2-1-58 Ushijima-honmachi, Toyama, 930-0859, Japan. taguti@toyama-med.jrc.or.jp.
authors: Tomio
authors: T
authors: Taguchi
mesh_terms: D019797:3-Iodobenzylguanidine; D017023:Coronary Angiography; D003329:Coronary Vasospasm / Q000150:complications / Q000000981:diagnostic imaging*; D003331:Coronary Vessels; D047548:Defibrillators; D004874:Ergonovine; D006323:Heart Arrest / Q000209:etiology; D006801:Humans; D008297:Male; D010120:Oxytocics / Q000627:therapeutic use; D011877:Radionuclide Imaging; D014693:Ventricular Fibrillation / Q000209:etiology*
chemical_list: D010120:Oxytocics; D019797:3-Iodobenzylguanidine; D004874:Ergonovine
references: J Nucl Med. 2002 Nov;43(11):1476-81
references: 12411551
references: Circ J. 2013;77(3):673-8
references: 23207956
references: Eur Heart J. 2004 Apr;25(7):551-7
references: 15120051
references: Circulation. 1987 Apr;75(4):877-87
references: 3829345
references: Circulation. 1990 Aug;82(2 Suppl):I103-13
references: 1973640
references: N Engl J Med. 1992 May 28;326(22):1451-5
references: 1574091
references: N Engl J Med. 1992 Sep 24;327(13):956; author reply 957
references: 1513355
references: J Nucl Med. 1995 Nov;36(11):2050-2
references: 7472596
references: J Am Coll Cardiol. 1997 Aug;30(2):370-6
references: 9247507
references: J Am Coll Cardiol. 1998 Jan;31(1):57-61
references: 9426018
references: Eur J Nucl Med. 1998 Mar;25(3):229-34
references: 9580854
references: Circ J. 2005 Feb;69(2):171-6
references: 15671608
references: J Interv Card Electrophysiol. 2008 Apr;21(3):223-6
references: 18297382
references: J Am Coll Cardiol. 2010 Apr 20;55(16):1713-20
references: 20394876
references: J Am Coll Cardiol. 2010 Jun 15;55(24):2769-77
references: 20538172
references: Circ Arrhythm Electrophysiol. 2011 Jun;4(3):295-302
references: 21406685
references: Intern Med. 2004 Mar;43(3):199-203
references: 15098600