cardiac Flashcards

Question

Complications of MI

Answer 1

``` Sudden death 25% of cases Arrhythmia (v-fib arrest) Heart failure Cardiogenic shock Multisystem organ failure Weakening of the arterial wall- Aneurysm (localized dilatation) Valvular regurgitation ```

Answer 2

``` Death of myocardial cells due to obstruction of blood flow 80% result from a thrombus obstructed a narrowed artery Gross Necrosis (pale yellow) Microscopic Necrotic myocardial cells Hemorrhage Inflammation ```

Answer 3

lad lesion artery obstruction- artery of sudden death, anterior infraction, 50% of cases

Answer 4

Patients present to ER or family doc with a variety of histories, time of onset etc In some MIs, there is no associated pain Can happen in the relatively young ie mid 30s Can happen in patients without obvious risk factors

Answer 5

Risk factors, history, clinical presentation 12 lead ECG – by changes in electrical patterns of the heart (look at st segment- if it elevated then we know the heart has been comprimised) Biomarkers- by release of compounds by the ischemic or necrotic heart tissue -(certain protein released into the circulation- can be mesures (high troponin levels)) In most provinces, in the very old, sudden death will be assumed to be myocardial infarction, without autopsy evidence

Answer 6

During an acute coronary event, a coronary artery becomes completely occluded. This deprives cardiac muscle of bloodflow (ischemia) and oxygen (hypoxia) causing death of the muscle and destruction of the cell (necrosis) Products of this ischemic and necrotic process find their way into the bloodstream where they can be measured . These are called biomarkers and can be diagnostic for myo-cardial infarction and necrosis.

Answer 7

Troponin Part of the contractile apparatus of muscle Different in heart and skeletal muscle

Answer 8

Mol wt 16,000 daltons Found in all muscle Non-specific marker Released earlier than other larger markers ie in the 1st several hours after an infarct

Answer 9

``` Present as a dimer with mol wt of 86,000 daltons Skeletal muscle has MM dimer Heart has MM and MB dimers Brain has BB dimer MB!!!! useful for MI diagnosis ```

Answer 10

myoglobin is released early (less than 5 hours), ck mb is release is slower and peaks at 12 hours, but now troponin had a peak aroun 8 hours and is long lasting- even at 35 hours

Answer 11

``` Mural thrombus Ventricular aneurysm Myocardial rupture (death) Cardiac tamponade (pericardial effusion) ```

Answer 12

``` Labs, 12 lead ECG If symptomatic and labs and or ECG are conclusive Cardiac catheterization (Angiogram) (1) no lesions (2) lesions < 50% (3) lesions > amenable to PCI (4) multiple lesion in multiple vessels ```

Answer 13

PCI refers to a invasive procedure in which a high grade coronary stenosis is dilated with a balloon tipped catheter system and/ or supported by metal prosthetic stents (scaffolds) to increase lumen diameter, restore blood flow and prevent myocardial ischemia.

Answer 14

Medical – Clot busting drugs (tPA, urokinase, streptokinase) Medical – Percutaneous Coronary Intervention Surgical – CABG –Coronary artery bypass graft Secondary prevention ( Means prevention of another event after the first one has already occurred diet, exercise, anticoagulant drugs (aspirin) etc, cholesterol lowering drugs(statins) antihypertensive drugs (ACE Inhibitors), beta blockers Primary prevention - diet, exercise, anticoagulant drugs (aspirin) etc, cholesterol lowering drugs(statins

Answer 15

Pump failure -> failure to pump out all blood that enters heart Congestion=Back pressure to all organs behind failed chamber Left heart failure -> pulmonary congestion & edema Right heart failure -> peripheral congestion & edema in the periphery (legs (large jugular veins) ``` Pulmonary Edema results from LHF Alveolar sacs fill with fluid  Dyspnoea (shortness of breath) On exertion Nocturnal Constant ```

Answer 16

grafts anatomosed to the heart

Answer 17

Systemic immunologic disease related to streptococcal infections Occurs two weeks after “strep throat” Antibodies to Streptococcus cross-react with cardiac antigens Cell mediated immune reaction Supressor/cytotoxic T lymphocytes and macrophages damage tissue Pathology of Rheumatic Fever Pancarditis (Endocarditis, Myocarditis, Pericarditis) vegetative growths develops on left side (aortic valves..)- leads to endocarditis

Answer 18

Inflammation of valves on the left side of the heart (valvulitis and ulcer formation) deposition of inflammatory cells, fibrin and platelets: (VEGETATIONS) Healing by fibrous scarring causes valve deformation Contracture leads to valve stenosis or valve insufficiency aortic valve stenosis- stiff

Answer 19

``` Valve Insufficiency (regurgitation) Mitral valve regurgitation reflux of blood from ventricle to atrium during systole Aortic regurgitation causes back flow of blood into the left ventricle during diastole The ventricles become dilated or hypertrophic- allows back flow of blood= coingestion instead of the ventricle being able to fill with new blood. - mitral regurgitation= the left atrium ``` Valve Stenosis Mitral stenosis causes a stagnation of blood into the LA Result in LA, pulmonary and right ventricular hypertension Aortic Stenosis causes a stagnation of blood into the left ventricle Results in LV hypertrophy and can lead to LA and pulmonary hypertension