Leanna R. Miller, RN, MN, CCRN-CSC, PCCN-CMC, CEN, CNRN, CMSRN, NP Education Specialist LRM Consulting Nashville, TN Objectives Evaluate common abnormalities that mimic myocardial infarction. Identify the criteria for pericarditis and evidence based interventions. Differentiate between pulmonary embolus and myocardial infarction using diagnostic criteria. Acute Coronary Syndromes Unstable Angina Non ST segment Elevation MI (NSTEMI) ST segment Elevation MI (STEMI) 1
Acute Coronary Syndromes Clinical Symptoms typical atypical Acute Coronary Syndromes Diagnostics Echocardiography Lab ABGs H & H enzymes 2
Acute Coronary Syndromes Diagnostics ECG (12 or 15 lead) T wave inversion ST segment elevation Q wave reciprocal ST segment depression SITE INDICATIVE RECIPROCAL Septal V 1, V 2 None Anterior V 2, V 3, V 4 None Anteroseptal V 1, V 2, V 3, V 4 None Lateral I, avl, V 5, V 6 II, III, avf Anterolateral I, avl, V 3, V 4, V 5, V 6 II, III, avf Inferior II, III, avf I, avl, V 2, V 3 Posterior None V 1, V 2 3
Variation to ST Segment Elevation 4
High acute risk factors for progression to myocardial infarction or death recurrent chest pain at rest dynamic ST-segment changes: ST-segment depression > 0.1 mv or transient (<30 min) STsegment elevation >0.1 mv elevated Troponin-I, Troponin-T, or CK-MB levels High acute risk factors for progression to myocardial infarction or death hemodynamic instability within the observation period major arrhythmias (ventricular tachycardia, ventricular fibrillation) early post-infarction unstable angina diabetes mellitus 5
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AMI LVH BBB Vpace BER Pericarditis LV Aneurysm Other Acute Pericarditis Introduction causes physical discomfort predisposition to tachydysrhythmias 7
Acute Pericarditis ECG Criteria ST segment elevation PR segment depression T wave flattening or inversion atrial dysrhythmias Acute Pericarditis ST segment elevation not isolated or discrete segments upward concavity may be notching at the junction of QRS and ST segment no reciprocal ST segment depression Acute Pericarditis PR interval interval between end of P wave and beginning of QRS may be depressed most often seen in lead II and V leads may be only ECG finding 8
Acute Pericarditis T wave flattening or inversion no T wave inversion during acute phase uncomplicated pericarditis: negative T waves only occur in leads which usually have negative T waves (avr & V 1 ) Acute Pericarditis Atrial dysrhythmias SVT in postoperative open heart patient treat with low dose steroids 9
Acute Pericarditis Complications (pericardial effusion) dampening of electrical output low voltage in all leads ST segment & T wave changes Acute Pericarditis Complications (pericardial effusion) freely rotating heart produces electrical alternans Dressler s Syndrome Introduction postmyocardial infarction syndrome autoimmune process 10
Dressler s Syndrome Clinical Presentation low grade fever chest pain (worsens with deep breath; lessens with sitting up and leaning forward) pericardial friction rub Dressler s Syndrome 12 lead ECG diffuse ST segment elevation across the precordial leads Dressler s Syndrome Treatment corticosteroid administration monitor for complications (effusion) 11
Pulmonary Embolus Introduction sudden massive PE produces ECG changes must get 12 lead to rule out MI Pulmonary Embolus ECG Findings RVH with strain RBBB pattern in V 1 large S wave in Lead I; large Q wave in Lead III (S 1 Q 3 pattern) 12
Ventricular Aneurysm Introduction (etiology) myocardial infarction congenital cardiomyopathy inflammatory idiopathic Ventricular Aneurysm Introduction infereolateral wall of LV symptoms include CHF & exercise induced syncope (VT) 13
Ventricular Aneurysm ECG Findings persistent ST segment elevation small q wave in II, III, & avf sustained VT with RBBB morphology 14
Ventricular Aneurysm Treatment surgical resection antidysrhythmics anticoagulants treat heart failure ablation therapy 15
Left Bundle Branch Block (LBBB) QRS duration > 0.12 second absence of septal q waves and S wave in I, avl, & V 5 6 (+ complex usually notched) broad QS or rs in V 1 3 (- complex) Left Bundle Branch Block (LBBB) S T, T wave changes in leads I, avl & V 5 6 (T wave opposite QRS) delayed intrinsicoid deflection over left ventricle (V 6 ); normal over V 1 Left Bundle Branch Block (LBBB) hypertensive heart disease aortic stenosis degenerative changes of the conduction system coronary artery disease 16
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LBBB with Acute Myocardial Infarction 18
Left Ventricular Hypertrophy Left Ventricular Hypertrophy 19
Brugada Syndrome autosomal dominant inheritance (SCN5A) gene sodium channel involvement in 25% of the patients Asian populations (58%) high incidence of polymorphic ventricular tachycardias Brugada Syndrome found in right precordial leads prominent J wave ST segment elevation in the absence of structural heart disease three types Brugada Syndrome Type I: ST segment elevation is triangular and T waves may be inverted in V 1 V 3 Type II: downward displacement of ST segment (does not reach baseline) Type III: middle part of ST segment touches baseline 20
Brugada Syndrome LBBB Infarction Resemblance ST segment elevation in the negatively deflected leads, (V 1 V 3 ) QS complexes in the negatively deflected leads, (V 1 V 3 ) Recognition Wide QRS QS in V 1 21
Ventricular Rhythms Infarction Resemblance ST segment elevation in the negatively deflected leads, (V 1 V 3 ) QS complexes in the negatively deflected leads, (V 1 V 3 ) Recognition Wide QRS following pacer spike Negative V 1 (RV paced) LVH Infarction Resemblance ST segment elevation in the negatively deflected leads, (V 1 V 3 ) Recognition Choose deepest S wave from V 1 and V 2 Choose tallest R wave from V 5 and V 6 Add deflections of tallest R wave and deepest S wave Suspect LVH if total is > 35 Pericarditis Infarction Resemblance ST segment elements in multiple leads Recognition ST segment elevation not in anatomical grouping PR segment depression Notching of the J point 22
Acute Pulmonary Emboli Infarction Resemblance RVH with strain pattern RBBB pattern in V 1 S 1 Q 3 on frontal plane Recognition Patient is symptomatic with atypical cardiac pain Elevated BMP r/o with spiral CT/angiogram Ventricular Aneurysm Infarction Resemblance High risk for ventricular dysrhythmias (VT with RBBB pattern) Inferolateral MI Persistent ST segment elevation Small q wave in II, III, avl Recognition Structural abnormality on ECHO CHF & exercise induced syncope (VT) Brugada Syndrome Infarction Resemblance Ventricular dysrhythmias (polymorphic VT) ST segment elevation in right precordial leads Recognition Autosomal dominant Asian culture No structural abnormality noted on ECHO 23
Prominent J with ST segment elevations septal MI RV cardiomyopathy pericardial effusion hypercalcemia Prominent J with ST segment elevations hyperkalemia acute pulmonary embolism subarachnoid hemorrhage tricyclic antidepressant intoxication 24
In Conclusion is the patient having a MI? a variety of conditions can mimic infarction ST segment changes 25