Cardiovascular Care Mark Curnow HASU UCH. AIMS OF SESSION Revision Cardiac Anatomy and physiology...
-
Upload
randell-holt -
Category
Documents
-
view
216 -
download
0
Transcript of Cardiovascular Care Mark Curnow HASU UCH. AIMS OF SESSION Revision Cardiac Anatomy and physiology...
Cardiovascular CareMark Curnow HASU UCH
AIMS OF SESSIONRevision Cardiac Anatomy and
physiologyElectrical Conduction relating to ECGAtrial Fibrillation and strokeManagement of Atrial FibrillationMonitoring on HASUBlood Pressure ManagementShock
Cardiac Anatomy and PhysiologyThe heart is essentially a sophisticated muscular
pump, propelling blood through the vascular system. It is fist sized & lies in the mediastinum between 2nd & 6th ribs.
The heart consists of 4 chambers – right & left atria and right & left vent. The chambers are separated by a fibro muscular septum.
A series of 4 valves lie between the chambers;between RA & RV - tricuspid valvebetween RV & pulmonary artery - pulmonary valvebetween LA & LV - mitral valvebetween LV & aorta - aortic valve.
HEART ANATOMY/BLOOD FLOW
HEART ANATOMY/ BLOOD FLOW
Cardiac Cycle
BLOOD FLOW AROUND THE BODY
ELECTRICAL SYSTEM OF THE HEART
Normal Cardiac Conduction
Cardiac Conduction- Cardiac Cycle
SINUS RHYTHM
Cardiac Conduction and the ECG
DEFINITION OF AF: Abnormal Conduction
Most commonly sustained cardiac arrhythmiaAtrial fibrillation is a type of arrhythmia in which the upper
chambers of the heart (the atria) beat erratically. This erratic beating can be extremely fast (in excess of 300 beats per minute), making it difficult for blood to circulate freely from the atria into the lower chambers of the heart, known as the ventricles.
AF is irregularly irregular, having no clear identifiable P waves.
Categories:First Episode.Paroxysmal: AF alternating with NSR, spontaneous reversionPersistent: AF alternates with NSR but requires treatment to
convert to NSRPermanent: Inability to convert to NSR with therapy
DEFINITION OF AF: Abnormal Conduction
AF: CAUSES Most cases of AF can be attributed to diseases
that affect the structure of the heart over many years.
Cardiomegaly: Chronic hypertension – causing enlargement of heart muscle, in particular enlarged atrium.
Diseases of the heart valvesPericarditis (swelling) Pericardial effusions (fluid around the heart )Myocardial Infarction (damage to heart muscle)SSS, (diseases of conduction system)Hyperthyroidism. Emotional stress, Nicotine, High etoh
consumption
AF AND STROKE: THE PROBLEMAF is very commonAt least 1.3 % UK population (600,000) have
known AFRising to over 4% in the over 65s and 10.2%
in patients over 75 yearsAF is a major predisposing factor to stroke16,000 strokes annually in patients with AF
in EnglandOf these approx 12,500 are thought to be
attributed to AF.
AF AND STROKE: THE PROBLEMIncidence of people with AF developing
stroke is: 4-6 times higher than a person with no AF.
Anticoagulants: Warfarin is superior in stroke prevention in AF.
AF strokes tend to be more severeWarfarin reduces stroke risk by 64%Aspirin reduces stroke risk by 22%NICE estimate that approximately 40% of
patients in whom warfarin is indicated are not receiving it, amounting to some 166,000 patients nationally
HOW AF CAN LEAD TO STROKE
HOW AF CAN LEAD TO STROKEConsequence of AF- Thrombus
AF: TREATMENTSDependant on type of AF and treatment aim. Look at history to identify any causes,
Echocardiography to look at heart structure. Pharmacological: Digoxin, amiodarone,
Flecanide, Beta blockers – Sotolol, Verapamil. Non Pharmacological: Cardioversion,
Ablation. Anticoagulation if no contraindication: For
prevention of AF related complications. INR 2.o-2.5
People with Disabling ischemic stroke in AF, aspirin 300mg for 2 weeks, then consider warfarin.
ATRIAL FLUTTER
Atrial flutter, another type of atrial arrythmia originating from a single focus within the atrium (usually the right) creating a rapid atrial rate from 250-400 beats per minute.
Due to the impulse being from a single focus, the atrial pattern on the ECG is consistent.
As with Atrial Fibrillation, there is an increased risk of stroke.
ATRIAL FLUTTER
MONITORING ON HASUHASU care provides the patient with 72 hours
of acute monitoring. Key element of care for people with acute
stroke is the maintenance of cerebral blood flow and oxygenation to prevent further brain damage after stroke (NICE)
Cardiac Rhythm (monitor for arrhythmia)Blood Pressure (maintain adequate CPP,
the blood pressure gradient across the brain)
Respiratory rate/ Oxygen Saturations (detect and treat hypoxia) sats>95% (NICE)
Arrhythmia Detection on HASUBed side monitoring
All patients on HASU monitored. All monitors linked to a central station with
continuous recording and recall facility.
Bedside Monitor vs 24hr Holter MonitorStudy (Germany) Sample of 136 patients, 29 were
newly diagnosed with PAF . 16 patients diagnosed PAF on bedside monitor prior to commencement of 24hr tape. Of the remaining 13 who were diagnosed PAF from bedside monitor, 24hr tape only picked up 3.
Therefore Continuous bedside ECG monitoring is more sensitive than 24-hour Holter ECG for PAF detection in acute stroke/TIA patients
Cerebrovasc Dis. 2010;30(4):410-7.
BLOOD PRESSURE MANAGEMENTBlood pressure monitoring is critical. Anti-hypertensive treatment in people with acute
stroke is recommended only if there is a hypertensive emergency with one of more of the following:
hypertensive encephalopathy , hypertensive nephropathy
hypertensive cardiac failure/myocardial infarction aortic dissection. Pre-eclampsia/eclampsia Intracerebral haemorrhage with systolic blood
pressure over 200 mmHg. (NICE) ESO (2009), Deem Hypertensive emergency as BP
> systolic 220 and diastolic >120.
BLOOD PRESSURE MANAGEMENTPatients suitable for thrombolysis should
have BP no higher than 185/110. (NICE)Avoid drops in blood pressure – maintain an
adequate cerebral perfusion pressure. Usually maintained by cerebral blood flow auto regulation.
An intracranial event can affect auto regulation, and an increased ICP and a decreased MAP can lower CPP which in turn cause secondary damage to brain.
BLOOD PRESSURE TREATMENTSHypertension: IV GTN: Mainly used in angina/ acute LVF. Causes dilation of smooth muscle within veins
and arteries. Leading to reduced myocardial workload and increased myocardial perfusion.
Causes hypotension. Can cause throbbing headache.
Labetolol Beta Blocker. Blocks beta adrenoreceptors
within the body. Reduces blood pressure by altering baroreceptors reflex sensitivity and block peripheral adrenoreceptors. They also cause reduction in heart rate. CHHIPS (2009)
SHOCKTypes: Cardiogenic: Pump Failure. Diminished
cardiac output which severely impairs tissue perfusion.
Causes: Myocardial Infarction / Ischemia End stage Cardiomyopathy Signs : Cold, pale clammy skin Hypotension. Tachycardia. Reduced urine output. Confusion. Treatment: Fluid challenge. Inotropes. IABP. Septic Shock Hypovoleamic.
CONCLUSION Remember: Close monitoring is essential on HASUFamiliarise yourself with the monitor (don't
be scared of it) Observe cardiac rhythm for changes,
especially irregularities. Monitor Hemodynamics, agree parameters
with team and manage changes early. Knowledge leads to empowerment. Always
aim to learn from your experiences by questioning, then tell someone else!!
THANK YOU