Cardiology 4 Flashcards
What is dilated cardiomyopathy?
Most common cardiomyopathy in young people, most of the time its idiopathic In some cases there's a history of myocarditis or chemotherapy agents Shortness of breath- murmur Enlarged ventricular shadow S3 gallop Caused by ischaemia and hypertension Other causes: Alcohol Beriberi (Vitamin B1 deficiency) Coxsackie Chagas disease Cocaine Doxorubicin Haemachromatosis Thiamine deficiency Causes biventricular heart failure, mitral and tricuspid regurgitation
What is restrictive cardiomyopathy?
Causes decreased ventricular compliance and diastolic dysfunction, it is most commonly caused by myocardial fibrosis after open heart surgery, and radiation
Caused by: amyloidosis, sarcoidosis, endocardial fibroelastosis
Low amplitude QRS
What is constrictive pericarditis?
A condition characterized by incomplete filling of the cardiac chambers due to thickening of the parietal pericardium.
Fatigue, hepatomegaly, dyspnea- pericardium can not accommodate changes in cardiac volume.
What is pulmonary insufficiency (regurgitation)?
Characterized by an incompetent pulmonary valve that leads to a backflow from the pulmonary artery to the right ventricle.
Pulmonary hypertension and a decrescendo diastolic murmur in the pulmonic area
Most common causes are pulmonary hypertension, IE, rheumatic heart disease
What is cardiac tamponade characterised by?
Sudden drop in blood pressure, altered mental status, jugular venous distention, pulsus paradoxus, and distant heart sounds
Results from pericardial effusion where blood or fluid accumulates in the pericardial space.
Cardiac tamponade is differentiated from other types of pericardial effusion by the accumulation of pericardial fluid under pressure, which compresses the heart chambers and decreases cardiac output.
What causes myocarditis?
Trypanosoma cruzi, a protozoan endemic to Central and South America.
Adenovirus, coxsackie B, parvovirus B19 (developed world)
Patients typically have a prodrome of fever, myalgia, and malaise several days prior to the onset of cardiac symptoms
S3 or S4 gallops
Respiratory distress
Shock (hypotension, hypoperfusion, altered mental status).
What is pericardial tamponade?
Often after trauma
Presents with jugular venous distension, hypotension and distant heart sounds (Becks triad)
This fluid exerts an increasing amount of pressure on the heart thus compromising its ability to fill and decreasing cardiac output
What is the TIMI score?
Age ≥65 years
At least three risk factors for coronary heart disease (these include hypertension, diabetes, dyslipidemia, smoking, or family history of early MI)
Prior coronary stenosis of ≥50%
ST-segment deviation on admission EKG
At least two anginal episodes in prior 24 hours
Elevated serum cardiac biomarkers
Use of aspirin over past seven days
What is a myocardial rupture?
Characterized by a laceration or tearing of the wall of the ventricles or atria of the heart.
Acute hemodynamic deterioration and sudden death
What are pulmonary embolisms?
Life threatening
A massive embolism obstructs the right ventricular outflow tract and therefore suddenly increases pulmonary vascular resistance, causing acute right heart failure
Rise in troponin due to ventricular ischaemia
How do PEs present?
Small/medium- breathlessness, pleuritic chest pain, haemoptysis, tachypnoeic, pleural rub
Massive- severe central chest pain, shocked, sweaty, pale, tachypnoea, tachycardia, syncope, raised JVP, right ventricular heave
Occurs more frequently in pregnancy, leading cause of maternal death
What is Kussmaul’s sign?
JVP rises paradoxically with inspiration
What are AAA?
Can be asymptomatic US offered to men 65-74 Epigastric or back pain Rupture- epigastric pain radiating to the back, hypovolaemic shock Surgery for symptomatic or >5.5cm
What is a thoracic aneurysm?
caused by cystic medial necrosis and atherosclerosis
Asymptomatic
Cause pressure on local structures- back pain, dysphagia, cough
Aortic regurgitation
What are the types of aneurysm (structurally)?
True- all layers bulge. fusiform: symmetrical. saccular (berry): asymmetrical
False (pseudoanerysm)- blood pools outside the vessel
Mycotic- infection
What causes aneurysms?
Hypertension (atrophy of tunica media) Male >60 Smoking Tertiary syphillis (inflammation of vasa vasorum) Bacteroides fragilis Pseudomonas aeruginosa Salmonella IE Aspergillus Candida Marfan's/Ehlers-danlos
What occurs when the papillary muscles are damaged?
Occurs commonly in the left ventricle and causes mitral regurgitation
What can hypovolaemia lead to?
Tachycardia, hypotension, sunken eyes and dry mucous membranes
Prerenal AKI- oliguria/anuria
What is the wells criteria for PE?
Symptoms of DVT, including leg swelling, redness, and tenderness to palpation (3 pts),
Tachycardia >100bpm (1.5 pts),
Recent surgery/immobilization >3 days (1.5 pts),
DVT/PE history (1.5 pts),
hemoptysis (1 pt), and
Malignancy (1 pt).
What murmur is heard in hypertrophic obstructive cardiomyopathy?
Crescendo-decrescendo murmur Softer if squats/handgrip Louder if stands/valsalva Bifid pulse S4 sound
What is seen in investigation of myocarditis?
Rise in troponin and creatine kinase
ECG- sinus tachycardia, T wave inversions, saddle shaped ST elevations
Enlarged heart on chest x-ray
Echo- inflamed heart muscle walls
Describe the different patterns of acute MI?
Regional MI (90%): infarct of 1 segment of ventricular wall (thrombus formation on an atheromatous plaque) Regional subendocardial infarction: lysis of thrombus/strong collateral supply limits infarct to subendocardial zone Circumferential subendocardial infarction (10%): general hypoperfusion of coronary arteries (hypotensive episode) in artherosclerotic arteries - no Q wave
Diagnosis of MI
Elevation in serum cardiac troponin levels
ST elevation/new LBBB = STEMI (generally full thickness myocardial infarct)
No ST elevation/LBBB, no Q waves = NSTEMI (partial thickness lesion)
Changes to a necrotic area post-MI
0-12h: loss of oxidative enzymes
12-24h: infarct pale & blotchy, intercellular oedema
24-72h: infarct area excites acute inflammatory response - soft and yellow with neutrophilic infiltration
3-10d: vascular granulation tissue organisation
10d-months: collagen deposition, infarct replaced by collagenous scar
