Cardio! Flashcards
What is Rivaroxaban?
-anticoagulant
-factor Xa inhibitor
-used to treat DVT and PE
-binds directly to factor Xa, blocking the amplification of the coagulation cascade, preventing the formation of thrombus
A PR interval > 200ms (five small squares) is …
first degree heart block
What ECG variants are considered normal in an athlete?
-sinus bradycardia
-junctional rhythm
-first degree heart block
-Mobitz type 1 (Wenckebach phenomenon)
What are the 3 classifications of acute coronary syndrome?
-STEMI
-NSTEMI
-unstable angina
Management guidance groups the patients into two groups: STEMI and NSTEMI/unstable angina
Describe the common management of all patients with acute coronary syndrome
Initial drug therapy:
-aspirin 300mg
-oxygen if <94%
-morphine for severe pain
-nitrates
-next step in management is to determine whether they meet the ECG criteria for STEMI
Once a STEMI has been confirmed the first step is to immediately assess eligibility for coronary reperfusion therapy. There are two types of coronary reperfusion therapy:
-percutaneous coronary intervention
-fibrinolysis
Describe management of STEMI
-STEMI identified
-aspirin 300mg
-PCI possible within 120 mins:
if yes-> give prasugrel (anti-platelet), radial access preferred, give unfractionated heparin + bailout glycoprotein IIb/IIIa inhibitor
-if PCI not possible within 120 mins -> fibrinolysis-> give an antithrombin at the same time and following procedure give ticagrelor
Describe the management for NSTEMI/unstable angina
-NSTEMI/unstable angina identified
-aspirin 300mg
-Fondaparinux if no immediate PCI planned
-estimate 6 month mortality (e.g. GRACE):
Low risk->conservative management- ticagrelor (anti-platelet)
Intermediate/high risk-> PCI- offer immediately if clinically instable (e.g. hypotensive), otherwise offer within 72 hours- give prasugrel or ticagrelor, give unfractionated heparin
What is the risk assessment tool used in acute coronary events?
The Global Registry of Acute Coronary Events (GRACE)
It takes into account:
-age, HR, BP, cardiac (Killip class) and renal function (serum creatinine), cardiac arrest on presentation, ECG findings, troponin levels
What is the first line treatment for hypertension in diabetes?
ACE inhibitors/ or A2RBs e.g. ramipril / or irbesartan
It also also important when assessing a patient with newly diagnosed hypertension to ensure they do not have any end-organ damage:
fundoscopy: to check for hypertensive retinopathy
urine dipstick: to check for renal disease, either as a cause or consequence of hypertension
ECG: to check for left ventricular hypertrophy or ischaemic heart disease
Name common drugs used to treat hypertension
-ACEi
-CCB
-thiazide type diuretic
-angiotensin II receptor blocker (A2RB)
What is the most common cause of secondary hypertension?
Primary hyperaldosteronism, including Conn’s syndrome
What is acute coronary syndrome?
Acute coronary syndrome is usually the result of a thrombus from an atherosclerotic plaque blocking a coronary artery.
When a thrombus forms in a fast-flowing artery, it is formed mainly of platelets.
This is why antiplatelet medications such as aspirin, clopidogrel and ticagrelor are the mainstay of treatment.
What is the root of the aorta and what are the branches from here?
The aortic root is where the aorta and the heart connect.
The right and left coronary arteries branch from the root of the aorta.
What does the right coronary artery supply?
right atrium, right ventricle, inferior aspect of the left ventricle and posterior septal area
What vessels come from the left coronary artery?
-circumflex artery- supplies the left atrium and the posterior aspect of the left ventricle
-left anterior descending-supplies the anterior aspect of left ventricle and anterior aspect of the septum
What is the presentation of acute coronary syndrome?
Central constricting chest pain often associated with:
-pain radiating to the jaw or arms
-nausea and vomiting
-sweating and clamminess
-a feeling of impending doom
-shortness of breath
-palpitations
-symptoms should continue at rest for more than 15 minutes
What are silent myocardial infarctions?
A silent myocardial infarction is when someone does not experience typical chest pain during acute coronary syndrome.
Patients with diabetes are at particular risk of silent MIs
What are the ECG changes in a STEMI
-ST-segment elevation
-new left bundle branch block
What are the ECG changes in NSTEMI?
-ST segment depression
-T wave inversion
What do pathological Q waves suggest in acute coronary syndrome?
a deep infarction involving the full thickness of the heart muscle (transmural) and typically appear 6 or more hours after the onset of symptoms
What are the corresponding ECG leads and heart area for the left coronary artery?
-anterolateral
-I, aVL, V3-6
What are the corresponding ECG leads and heart area for the left anterior descending?
-V1-4
-anterior
What are the corresponding ECG leads and heart area for the circumflex artery?
-I, aVL, V5-6
-lateral
What are the corresponding ECG leads and heart areas for the right coronary artery?
-II, III, aVF
-inferior
Describe troponin
-a protein in myocardium and skeletal muscle
-a rise in troponin is consistent with myocardial ischaemia, as they are released from the ischaemic muscle tissue
-troponin results are used to diagnose an NSTEMI- they are not required to diagnose a STEMI, as this is diagnosed based on the clinical presentation and ECG findings
-a high or rising troponin on repeat tests, in the context of suspected acute coronary syndrome, indicates a NSTEMI
Troponin is a non-specific marker, meaning that a raised troponin does not automatically imply acute coronary syndrome. The alternative causes of a raised troponin include:
-chronic kidney disease
-sepsis
-myocarditis
-aortic dissection
-pulmonary embolism
first-line interim anticoagulation in patients with suspected pulmonary embolism.
direct oral anticoagulants e.g. apixaban
Name examples of direct oral anticoagulants (DOAC)
Examples of direct oral anticoagulants include direct thrombin inhibitors (eg dabigatran) and direct factor Xa inhibitors (eg apixaban, rivaroxaban, edoxaban).
how does aspirin work?
Aspirin is a non-selective cyclooxygenase (COX) inhibitor that blocks the production of thromboxane A2 by platelets.
This impairs platelet aggregation.
The anti-platelet properties of aspirin make it useful in the prevention and treatment of arterial clots.
Aspirin is not used for suspected pulmonary embolism
How does glyceryl trinitrate work?
Glyceryl trinitrate produces nitric oxide which induces relaxation of the vascular smooth muscle cells to cause vasodilation.
It is commonly used to treat angina pectoris
How do statins work?
Statins inhibit the action of HMG-CoA reductase, the rate-limiting enzyme in hepatic cholesterol synthesis.
Statins lower cholesterol
