Mechanical Complications of MI Flashcards
Major mechanical complications post MI:
Major mechanical complications post MI:
1. Left Ventricular Free wall rupture 2. Ventricular septal rupture 3. Papillary muscle rupture
- rupture of aspects of the heart in general
Complications post MI in general
- cardiogenic shock
- re-infarction
- arrhythmia
- embolic
- mechanical
__ and reperfusion with _____ and thrombolysis
have dramatically reduced incidence of
mechanical complication <1%
Aspirin and reperfusion with percutaneous
coronary intervention (PCI) and thrombolysis
have dramatically reduced incidence of
mechanical complication <1%
- o Left ventricular free wall rupture 0.52% o Papillary muscle rupture 0.26% o Ventricular septal rupture 0.17%
what is the most frequent mechanical MI complication
left ventricular free wall rupture
T/F tx time for thrombolytic herapy affects outcome
true. thrombolytic therapy is indicated after the first few hours. the earlier to treatment, the better.
left ventricular free wall rupture is the most frequent MI mechanical complication and is the most fatal. 20% of people with this end up dying. What are the risk factors?
a ____ is a Contained rupture of
the myocardial wall by
pericardial adhesions
pseudoanrusym.Typically have to-and-
fro blood flow into a
cavity contained by
pericardium, thrombus,
or adhesions
___ aneurysm: outer
wall contains all layers
of the myocardium
True aneurysm: outer
wall contains all layers
of the myocardium
an early pseudoaneursym is more likely to coincide with __ MI
anterior MI. in later PAs, there is a low incidence in reperfusion area and is not anterior MI associated
Clinical presentation of free wall rupture
- cardiogenic shock
- sudden cardiac tamponade
- sudden death
- PEA.
50% of FWR will happen by 5 days, 90% by 14 days.
Cardiogenic shock is a state of cellular and tissue ___ due to :
• State of cellular and tissue hypoxia due to reduced
oxygen delivery and/or increased oxygen
consumption or inadequate oxygen utilization.
• Cardiogenic shock is due to intracardiac causes of
cardiac pump failure that result in reduced cardiac
output and thus reduced O2.
diagnosis of free wall rupture: depedning on stability and presence of cardiogenic shock, pericardiocentesis, echo, or cardiac MRI can help diagnose free wall rupture
management of free wall rupture
a mechanical problem requires mechanical solution
- Surgery (should not be delayed)
- Pericardial patch reinforced by surgical glue
there can be other things that will help:
intra-atrial BP, casopressors, inotropic support, fluids, pericardiocentesis to help tamponade (relieve fluid pressure build up)– this may extend a small tear though.
a ventricular septal rupture often happens because of necrosis _____. where in the septum dose the rupture occur?
a ventricular septal rupture often happens because of necrosis WITHIN the interventricular septum.
90% of ventricular septal rupture happens on the anteroapical side, adn 10% happens on the inferobasal side. this sucks. its harder to repair than anteroapical.
risk factors for Ventricular Septal Rupture
Anterior MIs are most likely to coincide with ventricular septal rupture (think location). Therefore, the LAD and posterior descending artery is more likely to be associated with VSR
The lateral collateral ligament infarct is very rarely associated with VSR because it’s too lateral
two types of ventricular septal defect/rupture
- LAD occlusion wiht anterior MI
- Inferior MI with PDA occlusion.
overall, both of htose arteries run down the middle of the front and back side of the heart.
VSR management
it’s easier to repair an antero-lateral VSR than inferobasal(PDA occlusion)
Pathology of ventricular septal defect can be due to a ____ ____ of blood. This is what causes all the symptoms
a left to ride intracardiac SHUNT.
in ventricular septal rupture, you’d see cardiogenic shock, ____ sided heart failure, a mumur on left sternal angle, and a ___ ____ on ECG.
How do you confirm diagnosis?
in ventricular septal defect, you’d see cardiogenic shock, RIGHT sided heart failure, a mumur on left sternal angle, and a AV NODAL (because septum is affected) on ECG.
Diagnosis confirmed with echocardiography.
ITS RIGHT HEART FAILURE BECAUSE OF THE LEFT TO RIGHT SHUNT. Ventricular septal rupture produces a usually large, left-to-right shunt (pulmonary-to-systemic flow >3:1) that places a volume load on the right ventricle, pulmonary circulation, left atrium, and left ventricle.
management of Ventricular Septal Rupture
it’s easier to repair anteroapical tear via PCI.
- it’s hard to repair an inferior tear.
in papillar muscle rupture, it Occurs 2-7 days post MI
• _____ side is 12X
more likely to rupture because of it’s _____
in papillar muscle rupture, it Occurs 2-7 days post MI
• POSTEROMEDIAL side is 12X
more likely to rupture because of it’s SINGLE BLOOD SUPPLY
risk factors of papillary muscle rupture
what causes the symptoms/pathology in papillary muscle rupture
papillary muscle rupture causes a regurgitation of blood into the left atrium from the venrical, which raises left atrial and pulmonary venous pressure and causing pulmonary edema.
- loss of stroke volume into the left atrium occurs at the expense of forward flow, and the systemic output of the heaert falls (thereofre low output state, low perfusion and thus cardiogenic shock)
diagnosing papillary muscle rupture
- on PA Catheter you see giant V waves
- on Echocardiography you see a flail MV leaflet, a severe MR or ruptured pieace of papillary muscle.
management of papillary muscle rupture
you need to have surgery to fix the muscle.
keypoints
