Complications for Acute MI Flashcards
Electrical or mechanical (relate to dysfunction of heart muscle)
2 broad categories
Relate to electrical system of the heart and initially present as a dysrhythmia
Depend on electrical system deprived of O2 or compensatory mechanism
The type of electrical complication depends on the location of the myocardial infarction (MI).
Atrial dysrhythmias
Atrioventricular (AV) heart block
Ventricular dysrhythmias
Electrical complications of MI
Sinus Bradycardia (HR <60 beats/min)
Sinus Tachycardia (HR >100 beats/min)
The type of electrical complication depends on the location of the myocardial infarction (MI).
Seen early
48 hours after right coronary artery - RCA supplies blood to SA and AV node
Considered comp if symptomatic
Usually occurs early
Inferior wall MI (Right coronary artery)
If symptomatic: Atropine
0.5 to 1.0 mg by intravenous push, repeated every 3 to 5 minutes to a maximum dose of 0.03 mg/kg
Sinus Bradycardia (HR <60 beats/min)
Seen early with LCA MI that supplies blood to LV
Gen compensatory mechanism to maintain CO and compensatory mechanism increases myocardium oxygen demand causing greater ischemic or infarcted area - measures need to be implemented to decrease myocardial O2 consumption
Anterior wall MI (Left coronary artery)
Treat the underlying cause to decrease myocardial oxygen consumption.
Sinus Tachycardia (HR >100 beats/min)
Premature atrial contractions (PAC’s)
Atrial fibrillation
Atrial dysrhythmias
Benign of themself
Frequent PAC’s go into Afib
Premature atrial contractions (PAC’s)
Can decrease cardiac output up to 20%
Develop this after MI greater risk for adverse events - developing pulmonary edema or shock or bleeding or stroke - atria fibrillating - fills with clots rather than pumping blood through and pts can have a stroke
Goal of Treatment is rhythm & rate control
Atrial fibrillation
Usually occurs during an MI
Seen in Inferior wall MI’s - right coronary artery supplies blood to AV node
Developing AV block during or after MI associated with greater mortality rate
Treatment for symptomatic AV blocks: transcutaneous or transvenous pacemaker.
Atrioventricular (AV) heart block
Electrical impulse starts in ventricle
Premature ventricular contractions (PVC’s)
Ventricular fibrillation
Mediations: beta blockers
Ventricular dysrhythmias
Can occur anytime. Most like to occur within the first 24 hours of having a MI
After cardiac cath lab and stent placement, on tele unit to monitor HR and rhythm to watch for this
When LV deprived of O2, irritable - looks like PVCs
Can look diff
2 diff forms
Ectopic beat started in diff part of ventricle
To many of them then all of sudden see couplets then three or four then vfib
Rate controlled with beta blockers
Treatment: Pharmacologically treated if PVC’s are:
More than 6 per minute, Closely coupled, Multiform shapes, Occur in bursts or three or more.
Frequent PVC’s increases the risk of sustained ventricular tachycardia
Treatment: O2 to reduce myocardial hypoxia, correct acid base imbalance, correct electrolyte imbalance.
Premature ventricular contractions (PVC’s)
Ventricular aneurysm
Ventricular septal rupture
Mitral papillary muscle rupture
Cardiac wall rupture
Pericarditis
Acute HF
Mechanical complications of MI
Not seen as often
Pts to hospital faster
LV aneyrism - secondary to big anterior wall MI
Later complication - days/weeks after MI - As body WBC go in to clean up infarcted tissue, weakens that area; LV high pressure side of heart and weakened area thins out and becomes aneurysmol - does not contract
A non-contractile, thinned LV wall that results from an acute transmural infarction.
Most commonly seen with left anterior descending artery (LAD).
Usually a late complication.
Prevention
Early reperfusion
Complications
Symptoms – correlate with the complication
Ventricular aneurysm
Acute heart failure
Have HF sx
Systemic emboli
Outpouching - area not pump; blood stagnats and coags; high risk for systemic emboli and stroke
Angina
Aneurysmol segment not beat - affects CO causing angina and ventricular dysrhythmias - VT
VT
Complications - Ventricular aneurysm
An abnormal communication between the right & left ventricle. - result of having ventricular septal wall MI
Rare complication of ventricular septal wall MI
Usually a late complication - days/weeks after MI - As body WBC go in to clean up infarcted tissue, weakens that area; LV high pressure side of heart and weakened area thins out and becomes aneurysmol - does not contract
Prevention
Early reperfusion
Complications/Symptoms
Treatment
Ventricular septal rupture
Sudden severe sx - go from fine to not fine
Severe chest pain
Crushing chest pain suddenly
Syncope
Fine to passing out; no warning
Hypotension
Sudden hemodynamic deterioration
Hemodynamically unstable
New communication between RV and LV = shunt; everytime LV pumping - pumping blood out to systemic vasculature and into RV - suddenly decreased CO
New holosystolic murmur at the left sternal boarder
Because of new communication
Complications/Symptoms - Ventricular septal rupture
Decrease afterload
New shunt have to make it easier for LV to make it easier to get the blood out
IABP
Nitroprusside given - decrease SVR; have to get interventional cardiology and get intraaortic balloon pump or impella device to decrease the afterload
Vasodilators
Does cause hypotension
Every time LV - least amount resistance to get blood out into systemic sys
Surgery
Only way fix this; open heart surgery
Have surgeon fix abnormal communication
Treatment - Ventricular septal rupture
Result of MI in area of heart where mitral valve leaflets anchored into the myocardium
Results in one or all leaflets not functioning properly - not synchronous; flapping in the wind; not doing anything
The valve does not fully close.
One or all mitral valve leaflets can be involved.
Complications/Symptoms
Treatment
Mitral papillary muscle rupture
Everytime LV beats - blood ejected through aortic valve into systemic circ and back through mitral valve - causes sudden onset of severe HF sx
Sx
Cardiogenic shock
Mitral valve regurgitation
Heart failure - Mitral papillary muscle rupture
LV
Tachypnea
Tachycardia
Cough
Bibasilar crackles
Gallop rhythms (S3 and S4)
Increased PA pressure
Hemoptysis
Cyanosis
Pulmonary edema
Fatigue
Dyspnea
Orthopnea
Paroxysmal nocturnal dyspnea
Nocturia
RV
Peripheral edema
Hepatomegaly
Splenomegaly
Hepatojugular reflex
Ascites
JVD
Increased central venous pressure
Pulmonary HTN
Weakness
Anorexia
Indigestion
Weight gain
Mental changes
Sx
Rapidly fine to symptomatic cardiogenic shock
Cardiogenic shock
Everytime blood pumps, have regurgitation
New murmur: High-pitched, holosystolic, blowing murmur at the cardiac apex heralds mitral valve regurgitation resulting from papillary muscle dysfunction.
Mitral valve regurgitation
Vasodilators
IABP
Definitive treatment: surgery to fix the valve
Treatment - Mitral papillary muscle rupture
Decrease SVR - more blood ejected into systemic vasculature - goal perfusing organs/end organ perfusion
Vasodilators
Interventional cardiology - intraaortic balloon pump/impella device
IABP
Occurs later
Usually a late complication - days/weeks after MI - As body WBC go in to clean up infarcted tissue, weakens that area; LV high pressure side of heart and weakened area thins out and becomes aneurysmol - does not contract
Occurs either within the first 24 hours or at 3 to 5 days.
Sudden onset
Complications/Symptoms:
Cardiac wall rupture
Sx sudden and severe
Cardiac tamponade
Cardiogenic shock
PEA - pulseless electrical activity - nothing wrong with electrical activity at first; all mechanical; LV cannot expand to pump blood out; blood in pericardial sac - preventing it from expanding
True emergency and most pts not make to treatment
Death - imminent within mins
Blood ejected from LV into pericardial sac with each pump - each pump - squishing LV so no longer expand to fill with blood to eject into systemic vasculature causing CO of 0 - not pumping blood out into systemic sys (brain and other end organs) - death
Complications/Symptoms: - Cardiac wall rupture