90 develop some form of cardiac arrhythmia 25 of

• 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.