Description : Rate of heart beat is determined by (a) Purkinje fibres (b) papillary muscles (c) AV node (d) SA node.
Last Answer : (d) SA node.
Description : Quinidine has the following action on electrophysiological properties of the heart except: A. Decreases automaticity of Purkinje fibres B. Abolishes after depolarizations C. Prolongs refractory period of atrial fibres D. Decreases membrane responsiveness of atrial and ventricular fibres
Last Answer : B. Abolishes after depolarizations
Description : why is sino atrio node pace maker? -Biology
Last Answer : answer:
Description : Assertion `:` The sino-atrial node (SAN) is called the pacemaker. Reason `:` SAN is responsible for initiating and maintaining the rhythmic contractil
Last Answer : Assertion `:` The sino-atrial node (SAN) is called the pacemaker. Reason `:` SAN is responsible ... False. D. If both Assertion & Reason are false.
Description : The correct route through which pulse-making impulse travels in the heart is (a) SA node → Purkinje fibres → bundle of His → AV node → heart muscles (b) SA node → AV node → bundle of His → Purkinje ... fibres → heart muscles (d) AV node → SA node → Purkinje fibres → bundle of His → heart muscles.
Last Answer : (b) SA node → AV node → bundle of His → Purkinje fibres → heart muscles
Description : if you suspect atrial flutter : Consider digoxin if not already in use because it frequently increases the conduction ratio and decreases the ventricular rate. , Avoid adrenergic and ... to the muscle decrease blood supply to the muscle the heart trying to beat fast ______________________________
Last Answer : decrease O2 supply to the muscle
Description : Which of the following drugs depresses automaticity of SA node as well as ectopic foci, abbreviates action potential duration of Purkinje fibres, and slows atrioventricular conduction: A. Propranolol B. Lignocaine C. Procainamide D. Bretylium
Last Answer : A. Propranolol
Description : Digitalis induced increase in refractory period of myocardial fibres is most consistent and pronounced in the: A. Atria B. Ventricles C. A-V node D. Purkinje fibres
Last Answer : C. A-V node
Description : The secondary pacemaker of the heart is known as the: a) AV node b) SA node c) Purkinje Bundle d) None of the above
Last Answer : ANSWER: A -- AV node
Description : Which of the following are not determinants of a postoperative cardiac complication? A. Myocardial infarct 4 months previously. B. Clinical evidence of congestive heart failure in a patient with 8.5 gm ... on electrocardiogram. D. A harsh aortic systolic murmur. E. Age over 70 years.
Last Answer : Answer: B DISCUSSION: Clinical evidence of congestive heart failure in a patient with 8.5 gm. per dl. hemoglobin concentration is a misleading sign. Evidence of congestive ... or ventricular contractions on the electrocardiogram are less strong determinants of a postoperative cardiac complication
Description : The following are true about cardiac contraction: a. the P wave initiates the atrial contraction b. atrial contribution to ventricular filling is most effective at fast heart rate. c. b wave is generated by atrial contraction d. fourth heart sound occurs during atrial contraction
Last Answer : fourth heart sound occurs during atrial contraction
Description : Which of the following ECG characteristics is usually seen when a patient's serum potassium level is low? a) U wave The U wave is an ECG waveform characteristic that may ... interval The QT interval is an ECG characteristic reflecting the time from ventricular depolarization to repolarization.
Last Answer : a) U wave The U wave is an ECG waveform characteristic that may reflect Purkinje fiber repolarization. It is usually seen when a patient’s serum potassium level is low.
Description : In humans, blood passes from the post caval to the diastolic right atrium of heart due to (a) stimulation of the sino auricular node (b) pressure difference between the post caval and atrium (c) pushing open of the venous valves (d) suction pull.
Last Answer : (b) pressure difference between the post caval and atrium
Description : n a failing heart therapeutic dose of digoxin has no effect on the following parameter: A. Cardiac output B. Heart rate C. Tone of ventricular fibres D. Cardiac vagal tone
Last Answer : C. Tone of ventricular fibres
Description : When no atrial impulse is conducted through the AV node into the ventricles, the patient is said to be experiencing which type of AV block? a) Third degree In third degree heart block, two impulses ... , type II, only some of the atrial impulses are conducted through the AV node into the ventricles.
Last Answer : a) Third degree In third degree heart block, two impulses stimulate the heart—one stimulates the ventricles and one stimulates the atria.
Description : What are Purkinje fibers? What is the function of the Purkinje fibres? -Biology
Description : Purkinje fibres mainly help in contraction of `:-`
Last Answer : Purkinje fibres mainly help in contraction of `:-` A. Right auricle B. Left ventricle C. Ventricles D. Aorta
Description : Purkinje fibres are found in `:-`
Last Answer : Purkinje fibres are found in `:-` A. Brain B. liver C. eyes D. Heart
Description : The electrophysiological effects of digitalis on Purkinje fibres include the following except: A. Enhancement of resting membrane potential B. Decrease in the slope of phase-0 depolarization C. Increase in the rate of phase-4 depolarization D. Abbreviation of action potential duration
Last Answer : A. Enhancement of resting membrane potential
Description : The cardiac pacemaker in a patient fails to function normally. The doctors find that an artificial pacemaker is to be grafted in him. It is likely that it will be grafted at the site of (a) atrioventricular bundle (b) Purkinje system (c) sinoatrial node (d) atrioventricular node.
Last Answer : (b) Purkinje system
Description : The following action of digoxin is responsible for beneficial effect in auricular fibrillation: A. Increased myocardial contractility B. Suppression of SA node C. Depression of A-V conduction D. Enhanced Purkinje fibre automaticity
Last Answer : C. Depression of A-V conduction
Description : Lidocaine is the preferred antiarrhythmic for emergency control of cardiac arrhythmias following acute myocardial infarction because (a) It has a rapidly developing and titratable antiarrhythmic action (b) It casues ... efficacy in atrial as well as ventricular arrhythmias (d) Both (a) and (b)
Last Answer : Ans: D
Description : Quinidine is now used primarily for (a) Conversion of auricular fibrillation to sinus rhythm (b) Control of ventricular rate in atrial flutter (c) Termination of ventricular tachycardia (d) Prevention of recurrences of atrial and ventricular extrasystoles/tachycardias
Description : In addition to pulmonary stenosis and ventricular septal defect, Tetralogy of Fallot includes: A A. Dextroposition of aorta and right ventricular hypertrophy B. Dextroposition of aorta and left ventricular hypertrophy C. Right ventricular hypertrophy and left atrial dilatation D. None of these
Last Answer : Dextroposition of aorta and right ventricular hypertrophy
Description : Identify the hormone with its correct matching of source and function. (a) Oxytocin - posterior pituitary, growth and maintenance of mammary glands. (b) Melatonin - pineal gland, regulates the ... sex organs. (d) Atrial natriuretic factor - ventricular wall, increases the blood pressure.
Last Answer : (b) Melatonin - pineal gland, regulates the normal rhythm of sleepwake cycle
Description : When the balloon on the distal tip of a pulmonary artery catheter is inflated and a pressure is measured, the measurement obtained is referred to as the a) pulmonary artery wedge ... Cardiac output is determined through thermodilution involving injection of fluid into the pulmonary artery catheter.
Last Answer : a) pulmonary artery wedge pressure. When the balloon is inflated, the tip of the catheter floats into smaller branches of the pulmonary arty until it can no longer be passed and the pressure is recorded, reflecting left atrial pressure and left ventricular end-diastolic pressure.
Description : ignocaine is effective in the following cardiac arrhythmia(s): A. Atrial fibrillation B. Paroxysmal supraventricular tachycardia C. Digitalis induced ventricular extrasystoles D. All of the above
Last Answer : C. Digitalis induced ventricular extrasystoles
Description : Lignocaine is the preferred antiarrhythmic for emergency control of cardiac arrhythmias following acute myocardial infarction because: A. It has a rapidly developing and titratable antiarrhythmic action B. It causes ... atrial as well as ventricular arrhythmias D. Both A' and B' are correct
Last Answer : D. Both ‘A’ and ‘B’ are correct
Description : yocardial Na+ channel blockade by lignocaine has the following characteristic: A. It blocks inactivated Na+ channels more than activated channels B. It blocks activated Na+ channels more than inactivated ... Na+ channels D. It produces more prominent blockade of atrial than ventricular Na+ channels
Last Answer : A. It blocks inactivated Na+ channels more than activated channels
Description : Quinidine is now used primarily for: A. Conversion of atrial fibrillation to sinus rhythm B. Control of ventricular rate in atrial flutter C. Termination of ventricular tachycardia D. Prevention of recurrences of atrial fibrillation/ ventricular tachycardia
Last Answer : D. Prevention of recurrences of atrial fibrillation/ ventricular tachycardia
Description : Quinidine can cause paradoxical tachycardia in a patient of: A. Sick sinus syndrome B. Atrial extrasystoles C. Atrial fibrillation D. Ventricular extrasystoles
Last Answer : C. Atrial fibrillation
Description : Digoxin produces the following effect(s) in atrial flutter: A. Reduces ventricular rate B. Prevents shift of A-V block to a lower grade C. Converts atrial flutter to atrial fibrillation D. All of the above
Last Answer : D. All of the above
Description : What is the usual response to digoxin in a patient of atrial fibrillation: A. Restoration of normal sinus rhythm B. Conversion of atrial fibrillation to atrial flutter C. Increase in ... decrease in ventricular rate D. Decrease in atrial fibrillation frequency, but increase in ventricular rate
Last Answer : C. Increase in atrial fibrillation frequency, but decrease in ventricular rate
Description : a. SAN generates as action potential which stimulates atrial systole. b. ECG is an electrical representation of the graphical activity of the heart du
Last Answer : a. SAN generates as action potential which stimulates atrial systole. b. ECG is an electrical ... one of the main symptoms of this disease.
Description : Which of the following terms is used to describe a tachycardia characterized by abrupt onset, abrupt cessation, and a QRS of normal duration? a) Paroxysmal atrial tachycardia PAT ... fibrillation Atrial fibrillation causes a rapid, disorganized, and uncoordinated twitching of atrial musculature.
Last Answer : a) Paroxysmal atrial tachycardia PAT is often caused by a conduction problem in the AV node and is now called AV nodal reentry tachycardia.
Description : The valves of the heart are attached to papillary muscles by `:-`
Last Answer : The valves of the heart are attached to papillary muscles by `:-` A. Columnae camae B. Chordae tendinae C. Tendinae D. Pectinati muscles
Description : Doctors use stethoscope to hear the sounds produced during each cardiac cycle. The second sound is heard when (a) AV node receives signal from SA node (b) AV valves open up (c) Ventricular ... blood from atria (d) Semilunar valves close down after the blood flows into vessels from ventricles.
Last Answer : (d) Semilunar valves close down after the blood flows into vessels from ventricles
Description : Which of the following ECG waveforms characterizes conduction of an electrical impulse through the left ventricle? a) QRS complex The QRS complex represents ventricular depolarization b) P ... QT interval is an ECG characteristic reflecting the time from ventricular depolarization to repolarization.
Last Answer : a) QRS complex The QRS complex represents ventricular depolarization
Description : Bundle of His is a network of (a) muscle fibres distributed throughout the heart walls (b) muscle fibres found only in the ventricle wall (c) nerve fibres distributed in ventricles (d) nerve fibres found throughout the heart.
Last Answer : (b) muscle fibres found only in the ventricle wall
Description : Which one of the following is correct pairing of a body part and the kind of muscle tissue that moves it? (a) Biceps of upper arm – S m o o t h m u s c l e fibres (b) Abdominal wall – Smooth muscle (c) Iris – Involuntary smooth muscle (d) Heart wall – Involuntary unstriated muscle
Last Answer : (b) Abdominal wall – Smooth muscle
Description : The four sketches (A, B, C and D) given below, represent four different types of animal tissues. Which one of these is correctly identified in the options given, along with its ... Smooth Heart Heart muscle contraction tissue (d) (A) Columnar Nephron Secretion epithelium and absorption
Last Answer : (a) (B) Glandular Intestine Secretion epithelium
Description : i need to have hip surgery done i have the wv medical card i can not get any one to help me i have AVN in both hips no dr around here will help me ?
Last Answer : You may need to contact the WV medical program plan to see if there are any physicians who can assist you. You may have also received a book with doctors listed, if so, refer to that.
Description : Stimulation of the cholinergic pathway results in: a. ciliary muscle contraction b. a decrease in atrial contractility c. gall bladder contraction d. all above
Last Answer : all above
Description : Histamine (a) May be released from mast cells by a number of therapeutic agents (b) Causes sedation (c) Decreases the force of contraction of ventricular muscle (d) Can cause strong contractions of the gravid human uterus
Description : A long-term effect of which of the following procedures post acute MI induces angioneogenesis? a) Transmyocardial laser revascularization TNR procedures usually involves making 20 to 40 channels in ventricular muscle. ... e.g., clopidigrel [Plavix]) therapy for 2 weeks and lifetime use of aspirin).
Last Answer : a) Transmyocardial laser revascularization TNR procedures usually involves making 20 to 40 channels in ventricular muscle. It is thought that some blood flows into the channels, decreasing the ischemia directly. ... healing a wound and new blood vessels form as a result of the inflammatory process.
Description : A patient has been taking digoxin for several years for chronic heart failure is about to receive atropine for another condition. A common effect of digoxin (at therapeutic blood levels) that can ... Increased atrial contractility (c) Increased PR interval on the ECG (d) Headaches (e) Tachycardia
Last Answer : Ans: C
Description : Which of the following regarding the anatomy of the heart is true? A. The aortic valve is tricuspid. B. The ascending aorta is entirely outside the pericardial sac. C. The left atrial appendage is ... trunk lies anterior to the ascending aorta. E. The right atrium is posterior to the left atrium.
Last Answer : Ans: A
Description : patient with rhumatic heart disease and had mitral valve stenosis Mitral vave diameter less than 1 mm In order to maintain COP what will happen : Left atrial hypertrophy and decrease ... dilatation with decrease pressure of contraction d- ventricle dilatation with decrease pressure of contraction .
Last Answer : Dilatation in the atrium with chamber hypertrophy