Cardiovascular assessment Flashcards
What is the CSEP-PATH procedure for blood pressure?
The CSEP-PATH procedure includes guidelines for when to proceed with appraisal based on systolic and diastolic blood pressure cutoffs.
* If systolic pressure is <160 mmHg AND diastolic pressure is <90 mmHg proceed with the appraisal
What should be done if a person’s blood pressure is elevated during a reading?
If either systolic pressure is ≥ 160 mmHg OR diastolic pressure is ≥ 90 mmHg, have the individual sit quietly for an additional 5 minutes. If the elevated reading persists after the second measure, physician clearance is recommended
What factors influence blood pressure?
Blood volume, vascular resistance (dilation vs. constriction), and cardiac output influence blood pressure
How does elevated blood pressure affect the heart?
Elevated blood pressure increases the “afterload” on the heart, which is the pressure the heart needs to overcome to eject blood during systole. It also can damage small vessels and capillaries in end-organs
What is the auscultation method for measuring blood pressure?
The auscultation method involves listening to bodily sounds using a stethoscope to identify systolic and diastolic pressures. It identifies the pressure at which blood is able to squeeze into the arm (systole) and the point at which the cuff no longer impedes blood flow (diastole)
What is the physiological principle behind blood pressure measurement with a cuff?
The cuff is inflated to stop blood flow, then deflated while listening for the turbulent flow of blood entering the arteries. The pressure in the arteries is higher than the cuff
What are Korotkoff sounds?
Korotkoff sounds are the tapping sounds heard through a stethoscope when taking blood pressure.
* Phase I is a clear “tapping” sound that indicates systolic pressure, and Phase V is when the “tapping” disappears, indicating diastolic pressure.
* There are also softer tapping sounds and muffled tapping sounds in Phases II, III, and IV, respectively
What are the proper conditions for taking blood pressure?
- The individual should be seated, relaxed, legs not crossed, and not talking.
- The cuff should be at the level of the heart with the arm supported.
- The cuff should be of appropriate size (L= 80% of arm circumference, W= 40% of arm circumference), and inflated to ~30 mmHg above systolic pressure
Where is blood pressure normally taken?
Blood pressure is normally taken from the brachial artery
What is the recommended rate of cuff deflation?
The cuff should be deflated at a rate of 2-3 mmHg/s
How does blood pressure measurement tend to be affected in terms of systolic and diastolic readings?
Systolic pressure tends to be underestimated, while diastolic pressure tends to be overestimated
How should repeated blood pressure measurements be timed?
Repeated blood pressure measures should be separated by 1+ minute
What is the effect of hydrostatic pressure on blood pressure measurements?
Hydrostatic pressure affects blood pressure due to the density of the blood, gravity, and height. There is an approximate ±0.8 mmHg change for every cm
What is the formula for hydrostatic pressure?
Pressure = ρ * g * h, where ρ is the density of liquid (blood), g is gravity (9.81 m/s^2), and h is height
What is the CSEP-PATH cutoff for heart rate?
If heart rate is 99 bpm or less (< 100 bpm), proceed with the appraisal. If >99 bpm, have the individual sit quietly for an additional 5 min. If the heart rate is still >99 bpm after a second reading, physician clearance is recommended
What is tachycardia?
Elevated HR is termed tachycardia
What is an electrocardiograph?
An electrocardiograph is the machine (oscilloscope/chart recorder) used to measure the electrical activity of the heart.
What is an electrocardiogram?
An electrocardiogram is the tracing of the electrical activity of the heart
What does an ECG measure?
An ECG measures the electrical activity of the heart along different vectors. It’s used to assess basic abnormalities in heart function
What is the scope of practice for a CSEP-CPT regarding ECG interpretation?
A CSEP-CPT is NOT sanctioned by CSEP to “Use an ECG for any purpose.”
What is the scope of practice for a CSEP-CEP regarding ECG and blood pressure?
A CSEP-CEP can measure and monitor heart rate, electric activity of the heart (using ECG), and blood pressure (by auscultation unless hearing impaired) at rest, during exercise, and post-exercise. These measures can be used to identify, but not diagnose, irregularities
What are the limitations for a CSEP-CEP regarding diagnosis?
A CSEP-CEP is not sanctioned to “Diagnose pathology based on any assessment or observation.”
How many electrodes and leads are required for a 12-lead ECG?
A 12-lead ECG requires 10 electrodes and provides 12 leads
What is a “lead” in ECG?
- A lead consists of two terminals (electrodes) that form an axis to provide a different view or tracing of the heart’s electrical activity.
- A lead is directional and aligned with a particular vector from the -ve electrode towards the +ve electrode.
What are the three orthogonal planes that a 12-lead ECG provides information about?
A 12-lead ECG provides spatial information about the heart’s electrical activity in the right-left, superior-inferior, and anterior-posterior planes.
What determines the ECG waveform?
The orientation of the lead (vector) in relation to the electrical current of the heart is what produces the ECG waveform.
How does the direction of the electrical current affect the ECG waveform?
If the direction of current is pointing in the same direction as the lead, it produces a positive deflection. If pointing in the opposite direction, it results in a negative deflection
What are limb leads?
Limb leads are 6 important vectors derived from the electrodes placed on the limbs
What are the bipolar limb leads?
Leads I, II, and III are referred to as bipolar leads
What are augmented limb leads?
Augmented (unipolar) limb leads use two electrodes to create a “null point” which is compared to the 3rd electrode. These are aVR, aVL, and aVF
What are precordial leads?
Precordial leads “look” at the heart in the horizontal plane and are located in close proximity to the heart. They measure the change in electrical potential along a vector from the heart towards the electrode and are “unipolar”
What are the standard deflections in an ECG?
P = Atria depolarization. QRS = Ventricle depolarization. T = Ventricle repolarization. U = repolarization of purkinje cells and/or papillary muscle of valves. R-R = 1 heart beat
What is the J point?
The J point is the transition point between the QRS complex and the ST segment
What are the normal ranges for the PR interval?
The normal PR interval is 0.12 - 0.20 seconds
What are the normal size ranges for the QRS complex?
The QRS complex should be <2.5 mm in size and the QRS interval is 0.07 - 0.11 seconds
What should be expected with the ST segment?
The ST segment should be smooth & gradual, which indicates the ventricular refractory period
What is the relationship between the QT interval and the R-R interval?
The QT interval should be < 1/2 the distance of the R-R interval.
What are the dimensions of a large and small box on an ECG grid?
One large box = 5 small boxes. On a standard chart recorder speed (25 mm/sec), one large box = 0.20 sec and one small box = 0.04 sec
How is heart rate calculated using the R-R interval?
Two methods for calculating heart rate are shown:
* Method 1: RR Interval (in seconds), Rate = 60 / RR Interval.
* Method 2: Rate = 1500 / # of small boxes between R-R intervals
What is the definition of tachycardia?
Tachycardia is a rapid beating greater than 100 bpm at rest in an untrained adult
What is bradycardia?
Bradycardia is a heart rate beating < 60 bpm at rest in an untrained adult (symptomatic < 50 bpm).
What is an arrhythmia?
Arrhythmia refers to an abnormal rate, rhythm, or conduction of electrical impulse in the heart
What can cause an arrhythmia?
Causes of arrhythmia are multifaceted and can be related to fever, dehydration, shock, hormonal imbalance, stress, various types of cardiac abnormalities, and heart failure
What is a premature ventricular contraction (PVC)?
A PVC is caused by depolarization of the ventricle before the atria can contract (absence of a P wave before another QRS complex). The QRS complex and T waves look abnormal compared to a normal ECG
When do PVCs need to be treated?
PVCs need to be treated when they occur at the rate of > 6 per minute
What is a Sinus Pause?
A sinus pause is a failure of the S-A node firing
What is Third Degree Heart Block?
Third degree heart block is where the atria and ventricles contract independently of each other. It can be identified by the presence of P waves that are not associated with QRS complexes. It is an emergency and often requires defibrillation
What are the characteristics of S-T depression and what may it indicate?
S-T segment depression/elevation of >1.0 mm 0.08 s after the J point may indicate Myocardial Ischemia
What is fibrillation and what is the treatment?
Fibrillation is uncoordinated atria or ventricle contractions caused by re-entry of electrical impulses, and it requires defibrillation
When is an ECG recommended in exercise testing centers?
An ECG is highly recommended in exercise testing centers, especially with untrained, older, or diseased individuals.
What should be done with an ECG during exercise testing?
A resting ECG should be established looking for abnormalities. A tracing should be recorded every workload during exercise
