Failure to diagnose myocardial infarction 2
Presentation
A 57-year-old man came to the emergency department (ED) by ambulance after developing chest tightness and shortness of breath followed by an unwitnessed syncopal episode.
The defendant emergency medicine physician saw the patient 11 minutes after his arrival. The patient reported that he used alcohol and tobacco. His medications included simvastatin, aspirin, quinapril, and metoprolol. He reported that he had a history of hypertension and a prior heart attack treated by placement of a coronary stent. The patient indicated that his episodes of chest tightness had been ongoing for several weeks and were worse upon exertion.
Physician action
The emergency medicine physician examined the patient and noted that he was bradycardic with diaphoresis and “pale skin color.” The patient’s lungs were “clear to auscultation bilaterally without wheezes, rales, rubs, rhonchi, or stridor.” Evaluation included a 12-lead EKG, cardiac enzymes, B-natriuretic peptide, CBC with differential, chemistry panel, and chest x-ray.
The emergency medicine physician interpreted the EKG as “normal sinus rhythm without ectopy or ST segment changes.” The computer interpretation recorded the findings as “sinus bradycardia (heart rate 53), inferior infarct — age undetermined.” The chest x-ray revealed congestive heart failure. Cardiac enzymes were interpreted as normal, with the exception of the B-natriuretic peptide, which was slightly elevated at 128 (normal range 0-100). In addition, the patient’s CO2 was slightly low at 21 (normal range 22-30).
The physician’s diagnosis was chest pain, stable angina, congestive heart failure, coronary artery disease, and hypertension. The patient was discharged 1 hour and 20 minutes after his arrival in what was noted to be stable condition. He was given a prescription for nitroglycerin and was advised to follow up with his cardiologist in two days or to return to the ED if he developed chest pain again.
The patient was found unconscious in his vehicle the next morning. EMS was notified and CPR was immediately instituted. The patient was intubated and an IV started. He was immediately transported by helicopter and arrived in the ED in full arrest. He was intubated and continued on appropriate CPR protocol with the use of epinephrine, atropine, bicarbonate, and lidocaine, but the patient died.
An autopsy was not performed. The death certificate was signed by the patient’s cardiologist listed the cause of death as sudden cardiac death secondary to ventricular tachycardia resulting from ischemic cardiomyopathy.
Allegations
Lawsuits were filed against the emergency medicine physician and the hospital. It was alleged that when the patient initially presented to the ED, he showed classic symptoms of coronary artery disease, unstable angina, and/or myocardial infarction. It was further alleged that the defendant physician knew that the EKG was abnormal and demonstrated ischemia and sinus bradycardia. Plaintiffs alleged that the emergency physician breached the standard of care by his failure to order more than one blood test to determine the levels of the cardiac enzymes; his failure to order more than one EKG; his failure to order an exercise electrocardiography test and cardiac perfusion scan; and his failure to obtain a cardiology consult prior to discharge.
Legal implications
Physicians who reviewed this case for the defense were critical, suggesting that this patient’s presentation required admission to the hospital and urgent cardiac consultation. It was noted that a single set of cardiac serum markers — particularly those obtained in the first 4 hours after the onset of chest pain — is unreliable in establishing or excluding a diagnosis of MI. The finding of congestive heart failure suggests acute decompensation of a stable status that should be evaluated. Additionally, syncope in a patient with structural heart disease requires evaluation.
Disposition
The case was settled on behalf of the emergency medicine physician and the hospital.
Risk management considerations
In this case, consultants felt that the emergency medicine physician should have been alerted to the possibility of acute myocardial infarction due to the patient’s reported syncope. The patient was not evaluated for the syncope, and this may have been significant. They stated that the patient’s combination of history, symptoms, and the computer-interpreted abnormal EKG, should have prompted further action on the part of the defendant. They felt that current literature indicated that a single set of cardiac serum markers, particularly ordered within the first 4 hours after onset of chest pain, is unreliable in ruling out a diagnosis of myocardial infarction.
Consultants felt that the physician should have considered and documented coordination of care with a cardiologist, ordered serial EKGs or cardiac enzymes, or admitted the patient.
Missed diagnosis of acute myocardial infarction is a common allegation against emergency medicine physicians. Emergency departments do physicians a service by implementing detailed, time-sensitive chest pain protocols. Protocols, however, have their limits and may not be able to address every possible patient scenario.
In addition, physicians are encouraged to consider the “big picture” and evaluate not only the patient’s medical history, but review all the patient’s reported symptoms. It is important that physicians recognize the limitations of diagnostic tests and consider the possibility of ordering further studies. Considering the “worst case scenario” in a chest pain case may prompt a physician to order serial EKGs or cardiac enzymes, to consult cardiology, or to admit the patient to the hospital.