Heart & Techy

HEART RATE   CALCULATION  IN  ECG-HEART AND TECHY First of all  we are  discussing  about  rate  of  e c g paper ,Before  calculating   heart rate  from an  e c g  you have  to know  what is  meant  by  standardisation  in an  e c g paper X  axis of the  paper  denotes the  time  and  Y  axis denotes the  amplitude.One   large box  in an  e c g paper  contain  25   small boxes  totally that is  5   small boxes  in  x  and  5   small boxes  in  y  axis. In x axis  duration of  one  small box  is 0.04  second  ,so  duration of   5   large box  is 0.2 second.In Y axis amplitude of one  small box  is 0.1 millivolt and  5   large box  is 0.5 millivolt, first step  while  reading ...

Add caption DIURETICS-CARDIOVASCULAR DRUGS   Diuretics   lower   blood pressure  by  increasing  the  kidneys   excretion  of  sodium  and  water ,which in  turn   reduces  the  volume  of  blood These are the  older   antihypertensive   agents , The   diuretics  are  classified  according to the  site  of  action  in the  kidney ,Thiazide diuretics  work  in the  tubules Loop   diuretics  are more potent than  thiazide  diuretics,They are usually  prescribed  when thiazide diuretics proves to be  insufficient  for  patients  with  heart failure Potassium  sparing diuretics  work  in the  area  were  potassium  is  excreted,Diuretics  are the  class  of  drugs  which are  less   expensive  in...

DOPPLER ECHOCARDIOGRAPHY-ECHOCARDIOGRAPHY D oppler   echocardiography   include s pulse   wave   continuous wave  and  colour   flow   doppler.Doppler   principle  is  applied  to  blood flow  within the  heart  and the  direction  and  velocity  of  blood flow  can be  determined  by  examining the   movement  of  red blood cells by the ultrasound beam. Doppler effect  is a  change  in the  observed frequency  of  sound  that  results  from  the motion  of the  source  or  target. Doppler ultrasound equipment   detects  a  frequency shift  and  determines  the  velocity  and  direction  of  red blood cells   flow concerning the ultrasound  beam doppler effect By  convention  the  velocity  ...

ECHOCARDIOGRAPHY 2D and M MODE IMAGING E CHOCARDIOGRAPHY 2D and M MODE IMAGING - Two-dimensional echo or B mode allow us to demonstrate the spatial relationship of structure for more accurate anatomic diagnosis of abnormalities of the heart and great vessels. It provides the tomographic images of the heart. It displays the return echoes as dots of varying brightness The brightness of the dot represents the strength of the return echo It provides the tomographic images of the heart by directing the transducer in various planes. Indications for 2 D echo are increasing with their increasing diagnostic accuracy. Some of these are to screen newborns and small infants who appear to have cardiac defects, to rule out cyanotic congenital heart disease in newborns with clinical findings of PPHN and persistent fetal circulation syndrome,...

D igoxin ecg changes- Digitalis  refers to  class  of  radioactive drugs   called   glycosides  which having both  mechanical  and  electrical effect   on  the  heart, Most commonly used digitalis preparation in current practise is  digoxin.It  have  positive  inotropic and  negative chronotropic effect  in our  heart Effect of digoxin Since a  number  of more efficacious and  safer medications  have  become   available ,the use of digitalis is mostly  limited  to  patients  with AF,systolic congestive  heart failure  and hypotension who cannot tolerate beta blockers or  calcium channel blockers , concentration  of digoxin in the serum can be  measured  by  radioimmunoassay.Therapeutic concentration range  is from  0.5-2  ng/mL Concentration   exceeding 2.0  are  associated ...

E lectrocardiogram and axis deviation: Mean   QRS  axis is the  magnitude  and  direction of a mean   cardiac  dipole or  vector  Factors  affecting mean cardiac vector are the position  of  heart , properties of the conduction system , electrical property  of ventricular myocardium and  muscle mass  of each ventricle electrocardiogram The  term   mean   QRS  axis  describes  the  general direction  in the  frontal plane  toward which the  qrs   complex  is predominantly pointed  Einthoven triangle  can easily  be converted to a triaxial   lead   diagram by having an axis of three standard limb   leads   3   augmented   limb leads  also  form  a triaxial  lead   system Triaxial lead system limb leads These  two  triaxial  lead   system  can be...

ELECTROCARDIOGRAM -ELECTRICAL ACTIVATION OF HEART T he central function of the heart is to contract rhythmically and pump blood to the lungs for oxygenation and then to pump this oxygen-enriched blood into the systemic circulation. The signal for cardiac contraction is the spread of electrical currents through the heart muscle. These currents are produced by pacemaker cells this property is known as automaticity. In our conduction system of the heart, there are various specialized cells are present. In which the SA node is known as the pacemaker of the heart. The signal for heartbeat initiation starts in the sinus node. This node is located in the right atrium near the opening of the superior vena cava. The initiation of cardiac contraction by electrical stimulation is known as electromechanical coupling. Akey part of this mechanism is the release of the calcium ions inside the atrial and ventricular heart muscle cells .This process links electrical and mechanical activation. The Ele...