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The Flat Electrocardiogram Systole Or Asystole?

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The Flat Electrocardiogram Systole Or Asystole? _JAccid Emerg Med 1998;15:185-189 185 SHORT REPORT J Accid Emerg Med: first published as 10.1136/emj.15.3.185 on 1 May 1998. Downloaded from The flat electrocardiogram systole or asystole? Robert Anthony Cocks, Mary Thompson, Yiu Wa Kwan Abstract lapse, she had suffered a syncopal episode and A case of stone heart syndrome is re- had fallen on the stairs at home. She quickly ported in a pregnant 27 year old West recovered from this initial episode and had not African patient, who suffered syncopal apparently suffered serious injury from the fall symptoms shortly before cardiac arrest. according to her husband. The electrocardiographic features were On examination she had no cardiac output those of asystole, but direct examination and no spontaneous respirations. There were of the heart at emergency thoracotomy in no external signs of injury. The cardiac arrest the A&E department revealed tetanic was managed according to contemporary contracture of the organ. At necropsy, the Resuscitation Council (UK) guidelines.' Fol- heart was of normal weight but showed lowing endotracheal intubation and the inser- areas offibrosis surrounding the bundle of tion of a right external jugular vein cannula, the His. The discrepancy between the ECG initial electrocardiogram rhythm was noted to features and the physiological state of the be asystole. This was treated with adrenaline heart raises the possibility that other cases and atropine. Following a second dose of of apparent asystole may not be what they adrenaline 1 mg, fine ventricular fibrillation seem. could not be ruled out, and two 200 J shocks (JAccid Emerg Med 1998;15:185-189) were delivered, after which the ECG trace was again isoelectric and certainly characteristic of Keywords: cardiac arrest; stone heart; asystole; myocar- asystole. dial fibrosis After 15 minutes of resuscitation, there was still no spontaneous return of circulation, and Case history external cardiac massage was not producing an A 27 year old West African patient was admit- impulse in either the carotid or the femoral http://emj.bmj.com/ ted to the accident and emergency department arteries. Left anterolateral thoracotomy was in cardiac arrest. One hour before her final col- performed for this indication,2 and to investi- Royal Postgraduate gate the possibility of cardiac tamponade: a Medical School, hard, cricket ball sized mass was found in the Hammersmith mediastinum, which appeared to represent the Hospital, Du Cane Road, London entire heart. Internal cardiac massage was also W12 OHS, UK ineffective, and resuscitation was discontinued on September 26, 2021 by guest. Protected copyright. Accident and after a further five minutes. Emergency Department NECROPSY EXAMINATION R A Cocks Necropsy findings were unremarkable apart for Department of the cardiovascular system. The heart weight Histopathology was 305 g. Histology of the myocardium M Thompson showed patchy myocardial fibrosis involving the bundle of His (fig 1). Both carotid arteries Faculty of Medicine, had intact 0.5 cm aneurysmal swellings at their The Chinese University of Hong bifurcation. Kong, Shatin, New The uterus contained a gestational sac of Territories, Hong Kong around 12 week size. Department of Pharmacology Discussion Y W Kwan Examination findings in this case were those of Correspondence to: stone heart syndrome, first described by Wu- Prof R A Cocks, Accident & kasch et al in 1972.' The original paper Emergency Medicine described 13 patients who developed a tetanic Academic Unit, Room G05/06, Cancer Centre, contracture or myocardial rigidity during cardi- Prince of Wales Hospital, opulmonary bypass. Attempts to resuscitate Shatin, New Territories, Figure 1 High power photomicrograph of the heart, these hearts using pharmacological and physical Hong Kong. showing cell degeneration andfibrosis in the bundle ofHis means were unsuccessful. At (large arrow). Compare with the underlying myocardium uniformly Accepted for publication (small arrow) which is normal. Haematoxylin and eosin necropsy, all of the patients were found to have 15 December 1997 stain, x215. left ventricular hypertrophy, and 12 of 13 had 186 Short report myocardial fibrosis. Heart weights were available trophy. However, in common with the patients for 10 of the patients, and all were increased. originally described, this woman had myocar- J Accid Emerg Med: first published as 10.1136/emj.15.3.185 on 1 May 1998. Downloaded from The mechanism of the development of stone dial fibrosis. No past medical history was avail- heart syndrome is thought to be one if irrevers- able to suggest an aetiology, but it is probable ible contracture of ischaemic heart muscle, that the fibrosis, which involved the bundle of with exhaustion of adenosine triphosphate His, precipitated a cardiac arrhythmia and car- (ATP) supplies. There is some evidence that diac arrest, resulting in irreversible ischaemic the use of calcium salts in resuscitation may change in the heart. While the flat ECG precipitate this condition,4 and catecholamines trace are known to aggravate cardiac damage in would normally be diagnosed as asystole, the ischaemia.5 Both endogenous and exogenous heart was in fact in the directly opposite state, levels of adrenaline are raised to very high lev- that of tetanic contracture. els in myocardial infarction and cardiac arrest, It is possible that many other cases of appar- because of stress and treatment.6 A recent ent asystole are not what they seem. paper from Japan reported the phenomenon of 1 A Statement by the Advanced Life Support Working Party firm myocardium during open chest resuscita- of the European Resuscitation Council. Resuscitation tion, but the significance of the presenting 1992;24:111-21. rhythm was not explored.7 2 Safar P, Bircher NG. Cardiopulmonary cerebral resuscitation, 3rd ed. London: W B Saunders Co, 1988. It is not clear whether pregnancy might have 3 Wukasch DC, Reul GJ, Milan D, Hallman GL, Cooley DA. compromised heart function in this patient, The "stone heart" syndrome. Surgery 1972;72:1071-80. 12 4 Meuret GM, Schindler MF, Scholler KL. Is calcium but at weeks gestation cardiac output is indicated in resuscitation? Experimental studies in dogs. increased by 1-1.5 litres/min, requiring extra Anaesthetist 1984;33:108-14. cardiac work. Additionally, a digoxin-like 5 Prichard BNC, Owens CWI, Smith CCT, Walden RJ. Heart and catecholamines. Acta Cardiol 199 1;3:309-22. immunoreactive substance (endoxin) is pro- 6 Little RA, Frayn PE, Randall P. Plasma catecholamines in duced during normal pregnancy,8 which would patients with acute myocardial infarction and in cardiac tend to interfere with normal ion flux in the arrest. Q J Med 1985;54:133-40. 7 Takino M, Okada Y Firm myocardium in cardiopulmonary cardiac muscle cells and produce an increase in resuscitation. Resuscitation 1996;33:101-6. intracellular sodium. 8 Gilson GJ, Graves SW, Qualls CR, Curet LB. Digoxin-like immunoreactive substance and sodium-potassium- The heart was of normal size and weight, adenosine triphosphate inhibition in normal pregnancy: a with no evidence of left ventricular hyper- longitudinal study. Obstet Gynecol 1997;89:743-6. http://emj.bmj.com/ on September 26, 2021 by guest. Protected copyright..
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