• 90% develop some form of cardiac arrhythmia. • 25% of patients rhythm abnormalities manifest within the first 24 hours • Risk of VF is greatest in the first hour and declines thereafter. • The incidence increases with an STEMI and decreases with NSTEMI. • Reperfusion strategies used to avoid ischemia and subsequent hemodynamic compromise. • Most peri-infarct arrhythmias are benign however, they can lead to malignant ventricular arrhythmias. Medscape.com
Mechanical Complications 3 major mechanical complications which can cause cardiogenic shock are: • Ventricular free wall rupture ▫ Laceration or tearing of the ventricular wall, of the papillary muscles, of the chordae tendinae, or the valves. • Ventricular septal rupture ▫ Laceration or tearing of the septal wall • Papillary muscle rupture with severe mitral regurgitation ▫ Papillary muscle tears collapsing the chordae tendinae leading to valve prolapse/inversion. Medscape.com
Schoen FJ, Saunders, 1989 Cardiac Rupture Syndromes Complications of Myocardial Infarction Papillary Muscle Rupture Ventricular Aneurysm Dr. William D. Edwards, Mayo Clinic, Rochester, MN. USA
Left Ventricular Aneurysms • Defined as a localized area of myocardium with abnormal outward bulging . • Risk factors for these aneurysms after acute myocardial infarction include the following: ▫ Female ▫ Total occlusion of the LAD artery ▫ Single-vessel disease ▫ Absence of previous angina ▫ Ventricular aneurysms Medscape.com
Pseudoaneurysms • Bulging/Ballooning of the ventricles are seen. • Are confirmed by means of echocardiography, MRI, or contrast-enhanced CT scanning. • Imaging of a pseudoaneurysm typically shows a relatively narrow neck and a complete absence of muscle in the wall of the pseudoaneurysm . Medscape.com
Ventricular Septal Ruptures • Rare, but a lethal complication • Tearing of the interventricular septum • Occurs 2-8 days after an infarction • Concomitant coronary artery bypass may be required. • Mortality rate is greater than 90%. • Ventricular rupture is more common in women, patients receiving non steroidal anti- inflammatory drugs (NSAIDs) or steroids. • An echocardiogram is used to define the abnormality Medscape.com
Schoen FJ: Interventional & Surgical Cardiovascular Pathology: Clinical Correlations & Basic Principles. Philadelphia, Saunders, 1989 Cardiac Rupture Syndromes Complications of Myocardial Infarction Anterior Myocardial Rupture Interventricular Septum Rupture
Associated Right Ventricular Infarction • Approx 1/3 of patients with inferior myocardial infarction develop RV infarction . • A right-sided ECG with greater than 1 mm ST elevation in V 3 R or V 4 R leads describes an RV infarct. • PE signs of right heart failure are elevated jugular venous pulsation, right-sided S 3 , Kussmaul sign, or hypotension.
You've reached the end of your free preview.
Want to read all 91 pages?
- Fall '19