Myocardial infraction Effects of ischemia injury and infarction

Myocardial infraction

Effects of ischemia, injury, and infarction on ECG Ischemia causes inversion of T wave because of altered repolarization. Cardiac muscle injury causes elevation of the ST segment and tall, symmetrical T waves. Q or QS waves develop because of the absence of depolarization current from the necrotic tissue. brunner & Suddarth’sxtbook of Medical-Surgical Nursing, 10 th edition. page 726.

brunner & Suddarth’sxtbook of Medical-Surgical Nursing, 10 th edition.

Note: ST segment before assessment of T waves, QT interval. the diagnosis of acute MI or ischemia is vital and depends on careful assessment of the ST segment. The ST segment holds the key to the diagnosis. Rapid ECG Interpretation. page 51 and 33

(1) …Page 108

Infarct Size - Small MI: ST elevation in two or three leads - Moderate MI: four or five leads - Large MI: six or seven leads - Extensive MI: eight or nine leads Rapid ECG Interpretation. Page 120

(2) Q WAVE MYOCARDIAL INFARCTION Q waves of acute infarction are always associated with abnormal ST elevation. (Pathologic Q waves are usually defined as duration >0. 04 s or >25% of R-wave amplitude) …Rapid ECG Interpretation. page 146

…page 53

(3) …Page 67 T WAVE

Rapid ECG Interpretation. Page 67

ﺍﻧﺰیﻢ : : : ﻫﺎ CK-MB The level starts to increase within a few hours and peaks within 24 hours of an MI. Myoglobin myoglobin level starts to increase within 1 to 3 hours and peaks within 12 hours after the onset of symptoms. Troponin increase in the level of troponin in the serum starts and peaks at approximately the same time as CK-MB. brunner & Suddarth’sxtbook of Medical-Surgical Nursing, 10 th edition. page 726

brunner & Suddarth’sxtbook of Medical-Surgical Nursing, 10 th edition. page 727

BRAUNWALD’S HEART DISEASE-A TEXTBOOK OFCARDIOVASCULAR MEDICINE. page 1069

: : : ﻋﻼﺋﻢ ﺍﻭﻟیﻪ Nausea and vomiting Pain Dizziness Palpitations cold perspiration Anxious skin pallor BRAUNWALD’S HEART DISEASE-A TEXTBOOK OFCARDIOVASCULAR MEDICINE. page 1085 …….

Signs and Symptoms Cardiovascular Chest pain Palpitations Heart sounds may include S 3, S 4 Increased jugular venous distention Pulse deficit brunner & Suddarth’sxtbook of Medical-Surgical Nursing, 10 th edition. page 725

Respiratory Shortness of breath dyspnea tachypnea crackles Pulmonary Gastrointestinal Nausea and vomiting. Genitourinary Decreased urinary output brunner & Suddarth’sxtbook of Medical-Surgical Nursing, 10 th edition. page 725

Neurologic Anxiety Restlessness Headache visual disturbances altered speech altered motor function changes in level of consciousness Psychological brunner & Suddarth’sxtbook of Medical-Surgical Nursing, 10 th edition. page 725

Acute Coronary Syndrome Decision Tree

MANAGEMENT OF ACUTE CORONARY SYNDROMES. Cardiac Care Network. 2013. page 31

NURSING DIAGNOSES -Ineffective cardiopulmonary tissue perfusion related to reduced coronary blood flow from coronary thrombus and atherosclerotic plaque. -Potential impaired gas exchange related to fluid overload from left ventricular dysfunction. brunner & Suddarth’sxtbook of Medical-Surgical Nursing, 10 th edition. page 729

-Anxiety related to fear of death -deficient knowledge about post-MI self-care -Potential altered peripheral tissue perfusion related to decreased cardiac output from left ventricular dysfunction. ……. . brunner & Suddarth’sxtbook of Medical-Surgical Nursing, 10 th edition. page 729

Nursing Interventions -RELIEVING PAIN AND OTHER SIGNS AND SYMPTOMS OF ISCHEMIA -IMPROVING RESPIRATORY FUNCTION -PROMOTING ADEQUATE TISSUE PERFUSION -REDUCING ANXIETY -MONITORING AND MANAGING POTENTIAL COMPLICATIONS brunner & Suddarth’sxtbook of Medical-Surgical Nursing, 10 th edition. page 730