Successful resuscitation from two cardiac arrests in a female patient with critical aortic stenosis , severe mitral regurgitation and coronary artery disease

Introduction. The incidence of sudden cardiac death in patients with severe symptomatic aortic stenosis is up to 34% and resuscitation is described as highly unsuccessful. Case report. A 72-year-old female patient with severe aortic stenosis combined with severe mitral regurgitation and three-vessel coronary artery disease was successfully resuscitated following two in-hospital cardiac arrests. The first cardiac arrest occurred immediately after intraarterial injection of low osmolar iodinated agent during coronary angiography. Angiography revealed 90% occlusion of the proximal left main coronary artery and circumflex branch. The second arrest followed induction of anesthesia. Following successful open-chest resuscitation, aortic valve replacement, mitral valvuloplasty and three-vessel aortocoronary bypass were performed. Postoperative pericardial tamponade required surgical revision. The patient recovered completely. Conclusion. Decision to start resuscitation may be justified in selected patients with critical aortic stenosis, even though cardiopulmonary resuscitation in such cases is generally considered futile.


Introduction
Severe aortic stenosis (AS) is defined as aortic valve area < 0.8 cm 2 (normal 2.5-3.5 cm 2 ) 1 whereas critical AS is defined as aortic valve index < 0.5 cm 2 /m 2 2 .Sudden death occurs in up to 34% of symptomatic AS patients 3 and car-diopulmonary resuscitation (CPR) is highly unsuccessful 1 .We presented a 72 year-old-female with critical AS, severe mitral regurgitation (MR) and three-vessel coronary artery disease with critical left main (LM) stenosis who, after successful resuscitation from two cardiac arrests, had emergency coronary artery bypass grafting (CABG), aortic valve re-Strana 715 Mijuškovi D, et al.Vojnosanit Pregl 2012; 69 (8): 714-716 placement (AVR) and mitral valve replacement (MVR), survived and went home in good condition.

Case report
A 72-year-old Caucasian female experienced dyspnea on exertion and retrosternal pain at the age of 70, and developed dyspnea at rest at the age of 72.The patient had no other medical problems.Administered medications included oral aspirin, atorvastatin, enalapril, metoprolol, furosemide and nitrates.Examination revealed 4/6 holosystolic murmur propagating to the axilla and neck.Electrocardiogram showed sinus rhythm, without Q waves or acute ST-T abnormalities.Echocardiography revealed aortic valve calcification, aortic value area 0.6 cm 2 , peak pressure gradient 111 mmHg by Doppler, mild aortic regurgitation, severe MR and preserved left ventricular function (Table 1).Clinically, the patient was at the New York Heart Association (NYHA) III functional status.During catheterization, immediately after contrast iohexol 4 (Omnipaque 350, GE Healthcare, Norway) was injected into the LM, the patient developed bradycardia and hypotension, rapidly deteriorating to severe dyspnea and asystolic cardiac arrest.Resuscitation started promptly, according to the American Heart Association guidelines.Twenty minutes following resuscitation, circulation was restored and spontaneous breathing returned.In the Intensive Care Unit (ICU), the patient regained consciousness, responded to instruction and was able to move all extremities after thirty minutes.Catheterization showed 90% LM, 60% left anterior descending and 90% circumflex stenosis.Left ventriculogram and right coronary artery angiogram were aborted.
Then, 95 minutes after the first arrest, the patient came to the operating room for emergency CABG-AVR-MVR.
General anesthesia was induced with diazepam 15 mg, sufentanil 25 g and pancuronium 10 mg, and maintained with sevoflurane 0.7-1.0ET MAC.Ten minutes after induction, the patient acutely developed hypotension and bradycardia unresponsive to iv epinephrine, and rapidly progressed to asystole.Resuscitation included emergency sternotomy, internal cardiac compressions and heparinization (400 units/kg).Heart exposure revealed 3 cm right ventricular wall laceration, likely from open heart massage.Following aortic and bi-caval cannulation, cardiopulmonary bypass (CPB) started.Myocardial protection included antegrade and retrograde cold blood cardioplegia.The patient had AVR (mechanical St. Jude 19, St. Jude Medical, Minnesota, USA), MVR (Duran Ancore ring 27, Medtronic, Minnesota, USA), three-vessel CABG (venous grafts to left anterior descending, circumflex and right coronary artery) and right ventricular (RV) wall laceration repair.
Cardiopulmonary bypass time was 230 min, aortic clamp time was 160 min, and the operation lasted 290 min.Intravenous epinephrine (0.067 g/kg/min) and dobutamine (maximum 15 g/kg/min) infusions were used, and the patient was stable after cardiopulmonary bypass (sinus rhythm, blood pressure 105/60 mmHg, central venous pressure 15 mmHg, hemoglobin 11.6 g/L, normal arterial blood gases).Postoperatively, a pulmonary artery catheter was inserted in the ICU (Table 2).Two hours after surgery, the patient developed atrial fibrillation and received three synchronized cardioversions and iv amiodarone loading, followed by oral amiodarone 1,200 mg/day.Despite postoperative troponin elevation (1.60 ng/mL), there were no wall motion abnormalities on echocardiography.
Four hours after surgery, chest tube drainage increased (1,000 mL/2 hours), central venous pressure increased to 22, urine output decreased, and hemoglobin dropped to 8.1 g/L.The patient received red blood cells 645 mL, fresh frozen plasma 610 mL, platelets 6 units, epinephrine increased to 16 g/kg/min, dobutamine to 20 g /kg/min and norepinephrine to 12 g/min for hypotension.Emergency echocardiography revealed large (18 mm thick) pericardial effusion, diastolic RV collapse, but no vena cava collapse.Emergency reexploration revealed bleeding from the right atrial cannulation site.After bleeding stopped and tamponade was relieved, epinephrine infusion decreased to 0.05 g/kg/min, norepinephrine stopped and urine output increased.
Approximately 8 h after the 2nd operation, the patient woke up and responded to commands.Despite postoperative liver dysfunction and non-oliguric renal insufficiency, the patient gradually improved, left the ICU on the day 27 and went home on the day 33.Two weeks after discharge, the patient was neurologically intact, and walked 5 km/day.

Discussion
This is probably the first report on successful resuscitation from two distinct cardiac arrests in a patient with a combined critical AS, severe MR and severe coronary artery disease.A predicted perioperative mortality for patients with NYHA III functional status, the same as the presented patient initially had, is 4.81% (logistic Euroscore).The first arrest occurred after iohexol injection for coronary angiography.Non-ionic contrasts are considered safer than ionic media 5 , and low-osmolar contrast is probably safe in patients with severe AS 6 .However, serious hemodynamic and electrophysiologic adverse events, including hypotension, myocardial dysfunction, arrhythmias, and cardiac arrest can occur after intraarterial or intracoronary iohexol injection 7 , and the reported risk of death was 6.6-100/ million during angiography with iohexol 4 .Although disastrous anaphylactic reactions to contrast are rare (0.03%) 5 , acute anaphylaxis cannot be excluded in this case.A predicted perioperative mortality (Logistic Euroscore) was at that moment 20.33%.
Emergency surgery was indicated in this case, due to symptomatic LM stenosis.As the second arrest occurred shortly after general anesthesia induction, myocardial ischemia, intraoperative myocardial infarction and arrhythmias 3 are all plausible etiologies.This particular patient had four reasons why resuscitation was unlikely to succeed: resuscitation from asystole has poor prognosis; external cardiac compressions are ineffective in severe AS, because overcoming the pressure gradient across the aortic valve is difficult 1 ; creating adequate cardiac output with CPR is problematic due to MR; and achieving adequate coronary perfusion is difficult due to severe LM stenosis.However, this patient was revived twice.Immediate sternotomy and internal cardiac compressions may explain CPR effectiveness after the 2nd arrest 8 .Prompt CPB initiation likely contributed to good outcome 9 , hypothermia during CBP probably provided some brain protection 10 .
Limitations of this report include not measuring serum triptase to exclude anaphylaxis to contrast, and not using a pulmonary artery catheter or transesophageal echocardiography for perioperative hemodynamic monitoring.

Conclusion
This report suggests that despite a low likelihood of survival, full resuscitation is worth pursuing in otherwise healthy patients with severe AS.