CVSR Quiz and BOFs Flashcards
The correct answer is:
- The heart is enveloped by this fluid-filled structure → Pericardium,
- Contracts during ventricular systole to prevent regurgitation and leakage of blood back into the atria → Papillary muscle,
- Open during ventricular relaxation and filling → Mitral valve
The correct answer is:
- Slows conduction, ensuring atrial contraction is complete before ventricular contraction commences. → Atrioventricular node,
- Ensures rapid spread of electrical activity to the ventricular apex and into the cardiac muscle. → His – Purkinje system,
- By virtue of its intrinsic rate of depolarization, provides secondary back up of heart rate (junctional escape) if the primary pacemaker region is injured and inactivated. → Atrioventricular node
The correct answer is:
- The time between two consecutive instances of this component of the surface ECG is used to determine the heart rate → R wave,
- This component of the ECG represents the depolarisation of the atria. → P wave,
- This component of the ECG represents the plateau of the ventricular action potential. → S-T segment
The correct answer is:
- → Normal Sinus Rhythm,
- → Ventricular tachycardia,
- → Bundle branch block
The correct answers are: Foramen ovale, Ductus arteriosus, Ductus venosus, Umbilical vein, Foramen ovale, Atrioventricular canal
The correct answer is: Foramen ovale
The correct answer is: Pulmonary trunk, Aorta
The correct answer is: Low ductal response to O2
The correct answer is: Close during ventricular contraction to prevent the backflow of blood into the atrium
The correct answer is: Supraventricular crest
The correct answer is: Sinus venosus
The correct answer is: increased in females and decreased in males.
The correct answer is:
- A 73 year old man with a prior history of ischaemic heart disease is found dead in his flat. At autopsy there is evidence of scarring in the anterior 2/3 of the interventricular septum. → Left anterior descending artery,
- A 65 year old woman collapses in the mall and is unable to be resuscitated. At autopsy there is a cardiac tamponade with rupture of the lateral aspect of the left ventricular wall. → Left marginal artery,
- A 55 year old smoker collapses at the golf course. He had a history of episodes of angina. He could not be rescuscitated. At autopsy there were multiple areas of infarction in the right atrium and right ventricle. → Right coronary artery
- Endothelial damage provides the stimulus for the lipid deposition that is atherosclerosis.
- Cytokines and chemokines are the cellular attractants produced during inflammatory responses
- C-reactive protein is an inflammatory marker rises as an early sign of inflammation.
The correct answer is: 1. Atherosclerosis is initiated by: → Endothelial damage, 2. Cells are attracted to the atherosclerotic site due to: → Cytokines & chemokines, 3. Measurement of this parameter can be used in the assessment of risk of atherosclerosis: → C-reactive protein
Endothelial dysfunction or damage is the key initiating event in atherosclerosis and be triggered by: mechanical shear stress (e.g. hypertension), biochemical abnormalities (e.g. hyperlipidemia, diabetes), immunological factors, inflammation, toxic substances (e.g. cigarette smoke), free radicals or genetic factors (e.g. familial hypertension)
The correct answer is: Endothelial dysfunction/damage
Thrombi can form on the surface of a plaque or inside it. This usually results from plaque rupture or superficial injury, exposing the inside of the plaque which is highly thrombogenic (due to the presence of tissue factor). Thrombi can further obstruct the vessel by increasing the volume of the plaque & changing its shape (if internal) or leading to thromboembolism (if external).
The correct answer is: Thrombus formation
The correct answer is:
- Blood flow to individual organs is primarily determined by: → Vascular resistance, 2. Korotkoff sounds heard during auscultatory determination of blood pressure represent: → Blood turbulence,
- At the end of systole, retrograde blood flow to the left ventricle is prevented by → Aortic valve closure
The conus arteriosus is the smooth walled section in the right ventricle leading to the semilunar valves of the pulmonary trunk. It assists in directing blood flow through the pulmonary semilunar valves.
The correct answer is: is the vestibule leading to the pulmonary semilunar valves in the right ventricle.
The apex of the heart is at the level of the 5th intercostal space on the midclavicular line.
The correct answer is: 5th intercostal space on the midclavicular line
The papillary muscles contract during ventricular contraction to maintain tension in the chordae tendinae and prevent the cusps of the atrioventricular valves from protruding into the atria with the force of ventricular contraction. This prevents backflow of blood into the atria. Infarction would lead to failure of the valve leaflets to be properly held in place and hence sounds (murmur) associated with valve insufficiency (regurgitation of blood from ventricle to atrium) during systole.
The correct answer is: contract to prevent the atrioventricular valves from protruding into the atria.
- Air movement into and out of the lungs is dependent upon the pressure difference between atmosphere and lungs (alveoli). Neither the relative partial pressures of O2 (Po2) and CO2 (Pco2) nor cardiac output and muscle blood flow play any part in this. Air movement will not be influenced by how much oxygen is in the atmosphere or in the lungs or blood.
- For CO2 to leave the body, it must cross from the blood to the lungs. As muscle metabolism increases, the Pco2 in the blood will increase. Thus the pulmonary artery Pco2 will rise well above the alveolar Pco2, driving CO2 out.
- Oxygen will leave the blood and diffuse into the muscle if the Po2 in capillary blood is greater than the muscle Po2. A higher cardiac output and higher blood pressure will deliver more blood to the muscle; however it is the concentration of oxygen within the blood when it arrives at the muscle capillaries (Po2) the oxygen will not leave the capillary if the capillary Po2 is not greater than the muscle Po2. Capillary oncotic pressure will affect water movement.
The correct answer is: 1. What is the driving force for air entering the lungs? → Atmospheric pressure, 2. What is the driving force for removing CO2 from the body? → Pulmonary artery Pco2, 3. What is the driving force for O2 to enter the active muscle? → Capillary Po2
Atherosclerosis and Marfan’s syndrome are the most common causes of abdominal aneurysm. His stature likely excludes Marfan’s syndrome and his smoking history and presence of coronary artery disease (angina) suggest atherosclerosis. Cystic medial degeneration describes the lesion associated with Marfan’s syndrome. Extra-vascuilar haematoma is not a “true aneurysm”. There is no indication of infection andinfection only accounts for <1% of abdominal aneurysms
The correct answer is: Atherosclerosis
- A split R-wave is indicative of a slowed conduction in one branch of the His-Purkinje system such that the muscle cells of one ventricle are activated and depolarise earlier the other, rather than the usual simultaneous activation
- A prolonged P-R interval is indicative of slowed conduction through the AV node. If too slow, the AV node may take over pace-making and the QRS complex occur regularly but will no longer be synchronised with each P wave
- An absent P wave but a regular QRS complex indicates failure of the S-A node to depolarise. The A_V node takes over as secondary pacemaker but at a slower than normal rate
The correct answer is: 1. The ECG record shows a persistent double peak or “split” in the R-wave → His – Purkinje system, 2. The QRS complex is separated from the P wave by a larger than normal P-R interval → Atrioventricular node, 3. A regular QRS complex occurs but the P wave is absent and R-R interval is prolonged and the heart rate slowed at rest → Sinoatrial node
The correct answer is: Foramen ovale
The correct answer is: Glycolysis is increased and calcium ions are overloaded in the contractile cell
β1-adrenoceptors mediate sympathetic NS stimulation of myocardial contractility . Increasing the diastolic length of the myocytes will increase force of contraction but contractility is defined as increased force of contraction at a given length. Contractility represents greater Ca2+ release and an increased use of energy; increased length takes advantage of more crossbridges being made and does not require more Ca2+ or more energy. Parasymathetic NS does not innervate the myocytes and decreased PS acticity will increase heart rate but not contractility
The correct answer is: Stimulation β1-adrenoceptors on myocytes and increased calcium permeability
The tunica media consists of the many smooth muscle cells required to contract and dilate with collagen and elastin that hold the muscle cells together and against high pressures.
Arteries and arterioles have substantial elastic laminar (internal and external) to resist overstretching and provide rebound in response to pulse pressure; they have extensive vasa vasorum to deliver blood and nutrients into the thicker, more muscular tunica media; Endothelial cells play a significant role in resistance vessels in their response to sheer stress and vasoactive circulating substances, however it is not a thicker layer.
Refer Lecture: Blood vessel and endothelial structure and function.
The correct answer is: more substantial tunica media layer of cells.
Valve vegetative growth will often give rise to emboli and the consequences depend on the location of the valves. Mitral and aortic valves are on the arterial side, increasing risk of stroke (via carotid arteries). Emboli having this point of origin can never pass into the venous system or the pulmonary system. Emboli will cause localised increases in resistance but with little effect on total peripheral resistance. Valve dysfunction may ultimately lead to heart failure and low BP rather than hypertension.
Refer GOAL: Cardiovascular histopathology
The correct answer is: Arterial embolism causing ischaemic stroke
The correct answer is:
- Which of the ECG disorders is commonly observed in left ventricular hypertrophy? → Enlarged QRS complex,
- Which of the ECG disorders is commonly observed in bundle branch block? → Split R wave,
- Which of the ECG disorders is commonly observed in the early stages of a myocardial infarction? → ST segment depression
The correct answer is:
1. Name the vessel that supplies blood to the posterior wall of the left ventricle? → Circumflex artery,
- Name the vessel that lies in the anterior interventricular groove, starts near the apex and joins the coronary sinus at its left end? → Great cardiac vein,
- The coronary arteries originate from which vessel? → Ascending aorta,
- Deoxygenated blood returns from the upper body to the right atrium of the heart via which vessel? → Superior vena cava,
- Blockage leading to ischaemia most commonly occurs in which vessel? → Left anterior descending (LAD) artery,
- The posterior interventricular artery supplies oxygenated blood to the interventricular septum. What vessel returns deoxygenated blood from the same region? → Middle cardiac vein,
- Name the vessel that returns oxygenated blood from the lungs to the heart? → Pulmonary vein,
- Cardiac surgeons pass a finger through the transverse pericardial sinus to allow the application of a surgical clamp or ligature in order to stop or divert the circulation of blood in ascending aorta and which of the above vessels? → Pulmonary trunk
The correct answer is:
1. Further investigation showing elevated levels of which serum marker suggests that he has suffered ischaemic myocardial damage ? → Troponins,
- Echocardiogaphic investigation shows a region of ventricular free wall that does not fully relax, which might suggest reduced activity of which circulating or intracellular component in that region? → Sarcoplasmic reticulum ATPase,
- The extent of damage is quite severe and with time his condition progresses into heart failure. Drug treatment to reduce activity of what intracellular or circulating component will indirectly increase force of contraction through facilitation of intracellular Ca++ accumulation? → Na+/K+ ATPase
Coagulative necrosis only becomes visible 8-12 hours after the infarct
The correct answer is: Normal appearances
Dressler syndrome is a type of pericarditis, inflammation of the sac surrounding the heart (pericardium). The inflammation is believed to be an immune system response following damage to heart tissue or the pericardium, such as a myocardial infarction, surgery or traumatic injury. The fever is the give-away sign.
The correct answer is: Pericarditis - Dressler syndrome
Coronary blood flow increases in response to increased metabolic demand, via coronary artery vasodilatation. Oxygen extraction is already very high in coronary circulation. Breathing rate will increase, but this just serves to maintain oxygen saturation in the face of the the higher pulmonary blood flow. Cardiac output will increase to deliver more blood to skeletal muscle, but coronary flow will not increase unless the coronary arterioles dilate as well.
The correct answer is: Increased coronary blood flow
If an infarct includes the coronary blood supply to the papillary muscle(s) papillary valve rupture is likely to occur in the dead/damaged muscle. This would likely compromise cardiac output and blood pressure (afterload) would fall rather than rise.The jugular pulse would not be affected until congestive heart failure included the right heart.
The correct answer is: papillary muscle rupture.
The correct answer is: The musculature of the right ventricle
The correct answer is:
- A 73 year old man with a prior history of ischaemic heart disease is found dead in his flat. At autopsy there is evidence of scarring in the anterior 2/3 of the interventricular septum. → Left anterior descending artery,
- A 65 year old woman collapses in the mall and is unable to be resuscitated. At autopsy there is a cardiac tamponade with rupture of the lateral aspect of the left ventricular wall. → Left marginal artery,
- A 55 year old smoker collapses at the golf course. He had a history of episodes of angina. He could not be rescuscitated. At autopsy there were multiple areas of infarction in the right atrium and right ventricle. → Right coronary artery
A range of key observations: rate is normal and rhythm is stable (~60bpm) (no premature beats or other arrhythmias). Abnormal shape seen in all cycles, characteristic of established arterial disease and ischaemia. Inversion of the T-wave, no clear ST segment (ST elevation. Finally, the split of the R-wave in every cycle represents a conduction differences down right and left bundles of His and Purkinje systems. This implies some ischaemia in one side of the conduction system.
Note that the heart rate is ~1/sec = 60/min.
Fever- rheumatic or pericarditis (incorrect) causes tachycardia.
Hypothyroidism (incorrect) causes bradycardia.
The correct answer is: Coronary artery disease
Factor III (also known as Tissue Factor or Tissue thromboplastin) is a protein expressed in all cells except endothelial cells. When it is released in tissue damage, it combines with Factor VII and greatly accelerates coagulation by activating both Factor IX and Factor X.
The correct answer is: release of Factor III by the subendothelium.
- Individuals lacking Factor VIII are prone to excessive bleeding unless treated with concentrated solutions of recombinant Factor VIII. Genetic inheritance is X-linked recessive so affected individuals are males and the gene is carried by females.
- The cleavage of circulating fibrinogen to fibrin, catalysed by thrombin, allows for formation of the fibrin-rich secondary haemostatic plug. Thrombin also catalyses the activation of Factor XI, Factor VIII and Factor V as well as playing a role in platelet activation.
- The Vitamin K dependent clotting factors are those numbered II, VII, IX and X (2, 7, 9 & 10).
The correct answer is: 1. Inherited deficiency of this substance leads to a condition known as Haemophilia A → Factor VIII, 2. This substance plays an important role in the conversion of fibrinogen to fibrin and has positive feedback effects on several other stages of the coagulation cascade → Thrombin, 3. Oral anticoagulants which act as Vitamin K antagonists (e.g. warfarin) would reduce the amount of this substance → Factor X
The correct answer is: Myoglobin
The correct answer is:
- A 41 year man with a long history of alcohol abuse suffered prolonged bleeding after excision of a skin lesion. The bleeding last more than 30 minutes and was difficult to stop even with pressure. → Liver disease,
- A newborn premature baby who suffered an intracranial haemorrhage. → Vitamin K deficiency,
- A 55 year old woman with biliary obstruction due to a head of pancreas tumour → Vitamin K deficiency
The correct answer is:
- A 21 year woman presents complaining of a recent onset of easy bruising. On examination you find multiple petechial haemorrhages on her skin, especially on her lower legs and you notice some on the mucous membranes of her mouth. → Platelet count,
- A 65 year old man with atrial fibrillation (AF) who is on daily oral warfarin for stroke prevention attends the practice, as he was ‘a little slow’ to stop bleeding after he cut himself accidently in the kitchen. → Prothrombin time (PT),
- A two year old boy, with no family history of bleeding disorders, develops a painful, swollen right knee after a fall. No fracture is seen on X-ray and a diagnosis of haemarthrosis is given. In hospital he has a prolonged activated partial prothrombin time (APPT) but normal Prothrombin time (PT). → Factor VIII
- A split R-wave is indicative of a slowed conduction in one branch of the His-Purkinje system such that the muscle cells of one ventricle are activated and depolarise earlier the other, rather than the usual simultaneous activation
- A prolonged P-R interval is indicative of slowed conduction through the AV node. If too slow, the AV node may take over pace-making and the QRS complex occur regularly but will no longer be synchronised with each P wave
- An absent P wave but a regular QRS complex indicates failure of the S-A node to depolarise. The A_V node takes over as secondary pacemaker but at a slower than normal rate
The correct answer is: 1. The ECG record shows a persistent double peak or “split” in the R-wave → His – Purkinje system, 2. The QRS complex is separated from the P wave by a larger than normal P-R interval → Atrioventricular node, 3. A regular QRS complex occurs but the P wave is absent and R-R interval is prolonged and the heart rate slowed at rest → Sinoatrial node
The major controller of capillary exchange is vascular smooth muscle tone. Vascular smooth muscle will alter resistance, and therefore plasma hydrostatic pressure and velocity. Also contraction of the VSM can close some of the vessels and reduce surface area. a). altering capillary permeability; is not correct because permeability changes are most important in pathological states. b). altering lymphatic drainage; is not correct although this is a source of pathological variation in exchange.
The correct answer is: vascular smooth muscle contraction.
The correct answer is:
1. What is the cause of her sudden loss of consciousness? → Pooling of blood in the lower limbs
, 2. How does wiggling her toes or walking help? → Increased venous return to the heart,
3. What is the body’s normally response upon standing, that prevents light headedness? → Increased sympathetic nervous activity to the heart and blood vessels
- About 2/3 of all blood volume is in the systemic venous stimulation at rest
- Largest total cross sectional area and least total resistance due to so many parallel vessels results in lowest velocity of flow.
- Increased metabolic activity increases limb blood flow which might increase 8 fold or more during intense exercise. However, the pulmonary circulation takes the entire cardiac output and will always have greater blood flow than any other individual organ or organ system this will increase by a similar volume per minute as does the limb flow, this represents only a 2-3 fold increase in cardiac output, therefore, proportionally the pulmonary blood flow may not increase to the same extent as the limb blood flow. However, with a sudden unprepared response like this, the major contributor is the cardiac output. Metabolic takes some time to “catch up”.
The correct answer is:
1. In order to meet his increased metabolic requirements, a greater volume of blood must be directed to the heart to support increased cardiac output. Which part of the cardiovascular system contains the greatest proportion of the total blood volume at rest? → Systemic veins and venules,
- With an increase in cardiac output, mean velocity of blood flow will increase. Which part of the cardiovascular system has the lowest velocity of blood flow at rest? → Systemic capillaries,
- In association the sudden increase in cardiac output, which part of the cardiovascular system has the greatest proportional increase in volume of blood flow at this time? → Pulmonary arteries and veins
The correct answer is:
- Blood flow to individual organs is primarily determined by: → Vascular resistance, 2. Korotkoff sounds heard during auscultatory determination of blood pressure represent: → Blood turbulence,
- Coronary artery blood flow is largely driven by: → Diastolic blood pressure
The correct answer is:
- The resistance to blood flow is greatest in the → Arterioles,
- The velocity of blood flow is lowest in the: → Capillaries,
- The percent of volume of blood is highest in the: → Veins
The predominant adrenergic receptor type in the myocardium and pacemaker regions of the heart is the β1 adrenoceptor.
The correct answer is: Beta 1 adrenoreceptors
Cardio selective indicates it acts on heart (muscle and pacemaker) via the particular adrenergic receptors located in the heart. As the adrenergic receptors mediate positive inotropic and positive chronotropic actions of adrenaline and noradrenaline in the heart, a drug that blocks these receptors (competitive antagonist) will reduce the effectiveness of adrenaline and noradrenaline and therefore reduce force and rate of cardiac contraction. Note that a drug that reduces sympathetic neurotransmitter release would have a similar effect, however it can in no way be regarded as cardio selective as it would reduce sympathetic activity at all receptor types innervated by the sympathetic NS.
The correct answer is: Decreasing the rate and force of cardiac contractions
For patients without CVD we use a combination of CV event risk estimates and BP levels before deciding on treatment.
The correct answer is: Drug therapy for hypertension is based on a combination of: estimation of absolute cardiovascular risk; and BP thresholds for treatment
Look at the ambulatory BP monitoring result below for a patient whose BP was 152/106 in clinic and choose the statement that best describes the pattern of BP recorded.
A) mean daytime average 129/79 mmHg suggests good control so no need for extra treatment.
B) normal lower night-time BP “dipping” seen
C) not all BP readings are normal (e.g. max of 149/108)
D) no evidence of very low BP and would need patient diary for postural symptoms
E) correct answer … Clinic BP 152/106 and first reading at start of ABPM when patient at the hospital 149/108. BP then falls to average daytime of 123/79 mmHg.
The correct answer is: Possible white coat hypertension
The pericardium provides a restrictive sack that normally prevents over-distension of the ventricle.
The correct answer is: Fibrous pericardium
- Arteriolar resistance decreases under the influence of epinephrine (beta2 receptors) mediated vasodilatation in order to increase the delivery of oxygen and maintain oxygen concentration in the muscle. Arteriolar resistance may even decrease prior to exercise in preparation / anticipation of the increased oxygen demand.
- Coronary arteriolar resistance will also decrease during exercise leading to an increase in coronary vascular conductance. Lactic acid and CO2 production may increase but this will be found in the venous not the arteriolar circulation. Sympathetic NS activity increases with exercise but coronary arterioles are not innervated.
- Oxygen concentration drops in the central venous circulation due to extraction during passage through the exercising muscles.
The correct answer is: 1. Which of the following is most likely to decrease in her skeletal muscle vasculature during exercise? → Arteriolar resistance, 2. Which of the following is most likely to increase in the coronary arterial circulation during exercise? → Vascular conductance, 3. Which of the following is most likely to decrease in the central venous circulation during exercise? → Oxygen concentration
Atropine would block muscarinic receptors, inhibiting sweating and reducing skin blood flow and thus reduce heat-loss processes. Muscarinic block would also dry mouth secretions and inhibit vagal slowing of the heart.
A beta agonist would (like atropine) raise the heart rate but with little effect on the skin and would likely reduce blood pressure due to peripheral vasodilatation in muscle beds. It would stimulate metabolism (and therefore generate heat) but without inhibiting processes of heat loss. A beta blocker would tend to slow the heart and have little effect on the skin. It might slow metabolism and therefore reduce heat generation.
A non-steroidal anti-inflammatory (aspirin-like) drug will have no effect on cardiovascular parameters and unless Mr Wilson has an elevated body temperature due to fever, it will have no effect on skin blood flow or sweating.
The correct answer is: The patient has been given a drug to inhibit muscarinic receptors
In a case-control study design, investigators identify cases, patients who have already developed the outcome of interest (coronary artery disease) then choose controls, persons who do not have the outcome of interest, but who are otherwise similar to the cases with respect to important determinants of outcome such as age, sex and concurrent medical conditions. Investigators can then assess retrospectively the relative frequency of exposure to the putative harmful agent (high plasma cholesterol) among the cases and controls. The coronary artery disease patients represent cases and the disease free patients represent controls.
The correct answer is: Case-control study
In a randomised controlled trial, one can be most certain about what the subjects have done / taken that might have influenced their final outcome. It provides the best insurance that the result was due to the intervention.
The correct answer is: Randomised -controlled trial
Integrate your knowledge of basic principles of pressure and flow with causes of infarction. The presence of diabetes and vascular disease predicates poor circulation but localisation to the right leg suggests involvement of the knee brace restricting blood flow. Hypoxia or a low cardiac output would make this worse but the swelling in the limb indicates that blood is entering but not leaving the limb indicating external compression sufficient to block venous flow but not arterial flow (Venous infarction caused by venous compression). If arterial flow was blocked there would be no swelling (blood not entering or leaving). Tachycardia (fast heart rate) is unlikely if he has been sleeping all the time. Loss of creatine kinase from cells is a marker of muscle cell damage but not the cause.
The correct answer is: Venous infarction caused by venous compression
Coronary dominance refers to which coronary artery supplies the posterior interventricular artery, which in turn supplies the posterior 1/3 of the interventricular septum. In left-dominant coronary circulation, the circumflex artery supplies the posterior interventricular artery and the posterior 1/3 of the interventricular septum, whilst the left anterior descending artery still supplies the anterior 2/3. As these are both branches of the left coronary artery, this supplies the entire interventricular septum, which is important clinically given this is the most frequently blocked coronary artery.
The correct answer is: Entirely by his left coronary artery
Adrenaline and noradrenaline have similar potency and efficacy at vascular alpha-receptors (alpha1) and stimulate a similar vasoconstriction in the resistance vessels to increase total peripheral resistance and diastolic BP. However, Adrenaline has greater potency than noradrenaline at smooth muscle (vascular and bronchiolar) where it causes relaxation and this vascular relaxation (mainly in the large vessels supplying skeletal muscle will tend to reduce resistance and counteract the rise in diastolic BP (Answer c)). Answer a) A partial agonist could provide a similar contrasting effect (same potency but less maximum effect) but is not true for adrenaline. Answer b) is a correct statement but not the correct reason for effects on diastolic BP.
The correct answer is: Adrenaline has greater potency on vascular beta-receptors
The cyanosis (turned blue) reflects impaired oxygenation of the blood which is exacerbated by breath-hold (suckling, crying). Tetralogy of Fallot, is a congenital condition associated with ventricular septal defect, pulmonic valve stenosis, an overriding aorta, and right ventricular hypertrophy. The combination of pulmonary valve stenosis and ventricular septal defect, plus the overriding aorta will lead to right to left shunt and bypass of the pulmonary circulation. Initially asymptomatic because sufficient blood is oxygenated for basic (non-active) metabolism. Atrial septal defect, coarctation of the aorta and patent ductus arteriosus will all lead to left to right shunts and increased flow through the pulmonary circulation. This requires excess work by the heart and will lead to left ventricular hypertrophy. All conditions would be associated with dyspnoea (shortness of breath) as the child becomes more physically active.
See Lecture: Common congenital malformations of the heart.
The correct answer is: Tetralogy of Fallot
Beta-blocker (called antagonist on this occasion to check your understanding of agonism and antagonism), is the treatment of choice for angina and a suitable first-line drug for hypertension especially when angina is also present as it reduces cardiac work and oxygen consumption. A calcium channel blocker acting on the heart might have been a suitable alternative, but not one acting in the periphery.
The correct answer is: Beta adrenoceptor-antagonist
The correct answer is:
1. Richard is a 38 year old man who was found to be hypertensive on a routine medical. Whilst examining Richard you notice that he has very large hands, significant prognathism and prominent supraorbital ridge. → Acromegaly,
- Lily is a 34 year old woman who has been referred by the practice nurse as she has had three blood pressure readings all greater than 160/100. On examination you discover a bruit over the right side of her posterior chest wall / back around L1. → Renal artery stenosis,
- George is a 46 year old man who presented for a general ‘check up’. During the examination and on several occasions subsequently, he has been found to have high blood pressure. Examination reveals that he has dry skin, some pre-tibial oedema and slow relaxing reflexes. → Hypothyroidism
The correct answer is: Trachea
Blood flow (cardiac output) is equal for pulmonary and systemic circulation. However, the pulmonary circulation is a low pressure system with lower resistance.
The correct answer is: Lower resistance
With inadequate production of surfactant in the immature lung the alveoli have a greater surface tension and tend to decrease in size and collapse. Lung collapse would lead to a lower then normal PO2 and faster breathing rate. Pulmonary vascular resistance increases with low PO2 (unlike systemic resistance which decreases in response to low PO2).
The correct answer is: Collapse of the small alveoli
Ductus arteriosus connects pulmonary artery to aorta during foetal development to shunt blood past the high resistance of the unused pulmonary vasculature. It closes at birth. If it remains patent then blood will pass from the highest pressure (aorta) to a point of lower pressure (pulmonary artery)
The correct answer is: From aorta to pulmonary artery
The correct answer is: has a cardiac impression and an aortic groove on its mediastinal surface.
The major vessel supplying the leg is the popliteal artery. It runs in the popliteal fossa, just posterior to the knee joint and complete flexion of the knee compresses this artery.
The correct answer is: Popliteal artery
The genicular arteries form an anastomosis around the knee joint and are particularly useful during complete knee flexion as an alternate route for blood from the thigh to the leg. They anastomose on the anterior surface of the knee, therefore are not occluded during knee flexion. Veins do not provide an alternate route for delivery of arterial flow.
The correct answer is: Superior and inferior genicular arteries
The phases of development are in order; Embryonic, Pseudoglandular, Canalicular, Terminal sac, Alveolar. Terminal bronchi from during the pseudoglandular phase then branch into respiratory bronchi in the canalicular phase and form terminal sacks and primitive alveoli during the terminal sac phase before the final development of mature alveoli which form in the alveolar phase and continue to from for up to 3 years.
The correct answer is: Canalicular
Pulmonary hypoxic vasoconstriction caused by low PO2 in the alveoli occurs throughout the lung because of the low PO2 of the inspired air.
The correct answer is: Generalised pulmonary vasoconstriction
Increased PCO2 will cause vasodilation of the cerebral arterioles and decreased PCO2 will cause vasoconstriction arterioles. There is little change to brain blood flow over a large decrease PO2. There is little direct sympathetic innervation to cerebral arteriole (stimulation of sympathetic cervical ganglion as no effect on cerebral blood flow). Histamine and prostacylin are circulating metabolites and have little or no effect as they are unable to cross the blood brain barrier.
The correct answer is: Carbon dioxide
Skin has extensive sympathetic innervation and is under extrinsic control. All the other organs listed are primarily local metabolic factors. Skeletal muscle is under sympathetic extrinsic control when at rest (not contracting).
The correct answer is: Skin
Reactive hyperaemia = An increase in blood flow to an organ occurs after a period of no blood flow and is proportional to the occlusion period.
The correct answer is: Reactive hyperaemia
- Hyperpnoea is any increased depth and rate of breathing. Hyperventilation is increased rate or depth of breathing to abnormal levels such that the healthy balance between breathing in O2 and breathing out CO2 is upset, with more CO2 cleared from the lungs, causing decreased arterial concentration of CO2. Tachypnoea is abnormally rapid breathing, Apnoea means absence of breathing. Dyspnoea means difficult breathing. Also known as shortness of breath or breathlessness, dyspnoea is a subjective awareness of the sensation of uncomfortable breathing.
- Dyspnoea means difficult breathing. Also known as shortness of breath or breathlessness, dyspnoea is a subjective awareness of the sensation of uncomfortable breathing.
- Hypercapnia means an abnormally high arterial CO2 concertation and is the main stimulus for breathing. Hypercapnia develops when breathing is disturbed to the extent of restricting lung clearance of CO2 which in turn reduces the concentration gradient for CO2 diffusion from blood. Hypercapnia will cause to (respiratory) acidosis. Conversely, acidosis of metabolic origin will induce hyperventilation to drive off CO2 (respiratory compensation) and reduce arterial CO2 concentration.
The correct answer is:
- What is the term used to describe Julie’s increase in breathing rate during normal exercise, that matches her increased metabolic demand? → Hyperpnoea, 2. What is the term used to describe the feeling that she cannot get enough air into her lungs to satisfy her body’s oxygen needs during an asthma episode. → Dyspnoea,
- What is the stimulus for her increased breathing effort and rate during an asthma episode? → Hypercapnia
The correct answer is: Decreased CO2