acute coronary systems Flashcards
cvs risk factors
hormones, family history, genetics, smoking, diet, lack of exercise, diabetes, obesity, socio-economic
primary prevention
stop the onset by giving advice/ treatment
secondary prevention
preventing consequences post early diagnosis
interconnected nature of cardiovascular disease lies within
there are vessels everywhere in the body
ischemia
blood flow & oxygen restricted to the certain part of the body
infarction
tissue death due to inadequate blood supply to the area
narrow vessels called
atheroma
exceeded oxygen in blood vessels
builds lactic acid
most common areas of infarction
- Heart - coronary artery atheroma
- Limb - femoral & popliteal arteries
- Brain - carotid arteries
main symptom of angina
tightness of the chest, exercise brought, relived by rest; dizziness, fatigue, nausea, shortness of breath
angina cause
atherosclerosis of coronary arteries supplying blood to the heart muscles
prevention of stable angina
low dose aspirin to reduce MI risk, diuretics, statins, ace inhibitors and beta blockers, lifestyle changes
coronary artery bypass
to improve blood flow
emergency angina treatment
GTN (glycerol trinitrate) under the tongue for first pass metabolism
GTN mode of action
GTN reduces the cardiac workload by relaxing the vessels, matching oxygen delivery to work and give relief to a patient
high venous contraction during angina increases the work so you need to reduce the preload or afterload
stemi symptoms
chest pain, often described as crushing or pressure-like feeling, radiating to the jaw and/or left arm, difficulty breathing, nausea
acute coronary syndromes
stemi, nstemi, stable and unstable angina
stemi treatment
PERCUTANEOUS CORONARY INTERVENTION (pci) = angioplasty within 3 hours and thrombolisers therapy
what is stemi
blockage of the coronal artery
reflected by ecg ST segment elevation and rise in troponin
what is nstemi
non-st-elevation - partial blockage of one of the coronary arteries, causing reduced flow of oxygen-rich blood to the heart muscle
management of unstable angina
asririn, nitrates, beta blockers, statins, calcium channel blockers
angina signs
hyperdynamic circulation, anaemia, hyperthyroidism
investigations for angina
ecg resting and after exercise, angiography
treatment for hypertension within angina
diuretics, Ca channel blockers, ace inhibitors, beta blockers
antiplatelet drugs
asprin and clopidogrel - inhibit platelet aggregation - decreases stroke and MI risk
aspirin risk dentistry
prolong the bleeding time following dental extraction
oral anticoagulants
warfarin and apixaban, taken to inhibit a clotting effect
warfarin is a vitamin k antagonist
warfarin dentistry
prolonged bleeding, INR has to be 2-4, avoid ID block, NSAIDs and fluconazole
apixaban
short half life and can be given as a short course for DVT, postpone extraction till after
statins are
lipid lowering drugs e.g. simvastatin, inhibit cholesterol synthesis in the liver so they reduce total cholesterol and LDL-cholesterol
do not prescribe statins with
antifungals
beta blockers
stop arrhythmias leading to cardiac arrest (Ventricular fibrillation – VF)
reduces heart muscle excitability, prevent increase in heart rate, reduce heart efficiency
- Atenolol – selective - β1 only
- Propranolol – non-selective – β1 and β2
diuretics
remove salt and water from body, can lead to Na+/K+ imbalance if not monitored carefully and can lead to dry mouth in the elderly
nitrates
Short acting – Glyceryl Trinitrate (GTN) - reduces chest pain through first pass metabolism
Long acting – Isosorbide Mononitrate - prevention of angina
calcium channel blockers
block calcium channels in smooth muscle - relaxation and vasodilation
e.g. Nifedipine, amlodipine (-pine)
ca channel blockers in dentistry
can lead to gingival hyperplasia in some, need to keep good OH
angiotensin converting enzyme (ACE) inhibitors
many on the market (-pril ending)
* Enalapril
* Ramapril
* Lisinopril
inhibit conversion of angiotensin I to angiotensin II
prevents aldosterone dependent reabsorption of salt and water.
reduce blood pressure
reduce excess salt and water retention
what are STEMI implications for his routine dental care of this diagnosis?
reduce anxiety and ensure right LA is given, be ready for BLS
dental treatment after stent placement
should be at least 6 weeks after the surgery, might consider antibiotic prophylaxis
patient 1 takes warfarin for atrial fibrillation.
patients on warfarin need to have an international
normalised ratio (INR) check done within 72 h of the extraction; if they have an unstable INR this time interval drops to 24 h. If the INR falls within the range 1—4, it is deemed safe to carry out the extraction. (Care should be taken at the upper end of this range, especially if multiple teeth or surgical procedures may be necessary.) Local measures should also be employed such as packing the socket with a haemostatic agent,
eg oxidised cellulose or collagen sponge, or resorbable gelatin sponge, and the socket should be sutured. Good postoperative instructions should be given and nonsteroidal anti-inflammatory drugs (NSAIDs) should not be prescribed
Postoperative tranexamic acid mouthwash may also be considered
patient 2 takes aspirin after a myocardial infarction
patient 2 takes aspirin and usually extractions can be carried out without any ill effect. If excessive bleeding occurs on removal of the tooth, it would be prudent to pack and suture the socket as in patient 1 and prescription of NSAIDs should be avoided
patient 3 takes aspirin and clopidrogrel after
placement of a cardiac stent.
clopidrogrel and aspirin may cause postoperative
bleeding, so it is good practice to pack and suture all sockets as in patient
The prescription of NSAIDs should be avoided, but postoperative tranexamic acid mouthwash may be considered. There is no preoperative blood test that is recommended
patient 4 takes aspirin and dipyridamole for stroke
prevention.
Dipyridamole and aspirin are a less potent combination than clopidrogrel and aspirin, and patients can be safely managed in the same manner as those on aspirin alone
patient 5 takes dabigatran etexilate (a thrombin
inhibitor) for atrial fibrillation.
Dabigatran etexilate is a new thrombin inhibitor. It
differs from warfarin in that vitamin K is not an effective reversal agent, and the drug’s action is not monitored by measuring the INR. It has a much shorter half-life of 12— 17 h, but this depends on renal activity. In patients
with poor renal function the half-life is increased
As there are no guidelines at present on how to
manage patients on these drugs who require surgical procedures in dentistry, it would be sensible to liaise with the patient’s haematologist about management. It would seem prudent to check the patient’s renal function if possible because this will give an indication
of the drug’s half-life. It is also suggested that the
patient should be treated as late as is feasibly possibly after administration of the drug, eg if the patient takes it at night, then treat the following afternoon. Local measures such as packing, suturing and postoperative administration of tranexamic acid mouthwash are also suggested
list three medical conditions for which patients
may be prescribed warfarin.
Atrial fibrillation
Prosthetic heart valves
Deep vein thrombosis
Pulmonary embolus
Cerebrovascular accident
Antiphospholipid syndrome
drugs that interact with warfarin
- Fluconazole — enhances anticoagulant effect
- Metronidazole — enhances anticoagulant effect
- Carbamazepine (epilepsy) — reduces anticoagulant effect
what type of drug is tranexamic acid?
how is it administered and when would it be used?
tranexamic acid is an ANTIFIBRINOLYTIC agent
used topically as a mouthwash or by soaking swabs in it and getting the patient to bite on them
can also be given orally or intravenously
used to prevent and control bleeding especially during and after the procedure.
What are the dental implications of the
following findings in a patient’s medical history:
(a) The patient is taking glyceryl trinitrate (GTN).
GTN is a vasodilator and also reduces left ventricular work by reducing venous return.
Reducing stress by providing good anaesthesia and not subjecting patients to long appointments will minimise the likelihood of the patient having an attack.
In addition,the patient should take GTN at the start of an appointment.
What are the dental implications of the
following findings in a patient’s medical history:
The patient is taking nifedipine.
Nifedipine is a calcium-channel blocker used to treat
hypertension.
Hypertensive patients are at increased risk of other cardiovascular disease.
Routine dental treatment may need to be postponed if the patient’s blood pressure is greater than 160/110 mmHg.
Hypertensive patients are more likely to have
EXCESSIVE BLEEDING following extractions.
Ca+ Channel Blockers can cause gingival hyperplasia.
You are carrying out a dental extraction on a 70-year-old man in your practice. He pushes your hand away and tells you to stop leaning on his chest (which you are not doing). What is the likely diagnosis?
Angina
What other symptoms may he be
experiencing?
The patient may also be experiencing:
* Central chest/retrosternal pain
* Band-like chest pain
* Pain radiating to the mandible/left arm
How would you proceed in this situation?
Management of ischaemic chest pain:
1 Stop the procedure
2 Make the patient sit up
3 Administer sublingual GTN
4 Administer oxygen
The pain continues and becomes more severe.
He becomes pale, clammy and feels nauseous.
What has happened?
The ischaemic chest pain has progressed from angina (reversible) to MYOCARDIAL INFARCTION (irreversible).
How would you proceed?
call for help from nursing staff
call 999
prepare for BLS
30 compressions to 2 rescue breaths
15 l of oxygen
use defibrillator if possible
