Pericardium andExternal Features of Heart

Life support Feeding Tubes

Ionotropes

Total Parenteral Nutrition

Mechanical ventilation

Heart / Lung bypass

Urinary catheterization

Dialysis

Cardiopulmonary resuscitation

Defibrillation

Artificial pacemaker

Vitals

HeartLungsBrain

TemperatureRespiratory RateHeart Rate (Pulse)Blood Pressure

Assessment of the level at which an individual is functi oning

Thoracic organs

HeartLungsThymus (Till puberty)

Heart att ack / Myocardial infarcti on is one of the common causes of sudden death

Development of Heart

Lateral plate mesodermSingle heart tubeInitially antero-posterior axisAtt ached by arterial and venous endsFolds ventrally and bulges in 5 regions

1. Truncus arteriosus2. Bulbus cordis3. Primitive ventricle4. Primitive atrium5. Sinus venosus

Gross structure

Two atriaTwo ventriclesAortaPumonary Trunk – Pulm. ArteriesPulmonary veinsSup & Inf. Vena cavaConduction system SA Node AV Node Purkinje Fibres

Heart functions rhythymically inspite of :Located among other structures in a fi xedThoracic cage

Lungs expanding & contracti ng withRespirati on

Diaphragm moves from below

Post vertebral column moves in variousPostures

Oesophagus ballooning during ingesti on of food

Beati ng at 72 beats per minute

Receiving and pumping blood of 5 liters

Chambers are not at geometrical convenience

Intra-thorcic pressures altering with coughing/sneezing/vomiti ng etc.

PericardiumConical fi brous sacContains heart & roots of great vessels

Situated -- in middle mediasti num - behind body of sternum and 2nd to 6 th costal carti lages- In front of bodies of 5 th to 8 th thoracic vertebrae

Components

Outer fi brous sacInner serous sacHeart lies within fi brous pericardium (Intra fi brous) outside serous pericardium (extra serous)

Fibrous pericardium

Cone shaped bagTruncated apexKeeps heart in positi onPrevents over distension of heartOpen sac pierced by some blood vessels

Att achments

AboveBlends with ext. coat of aorta and Pulm.trunkConti nuous with pre-tracheal fasciaBelowFuses with upper surface of central tendon and part ofMusculature of left part of diaphragm(Heart & Diaphragm develop from septum transversum)In frontAtt ached to sternum bySuperior & Inferior sterno-pericardial ligamentsStructures piercingAsceding aorta, Sup. & Inf. Venacavae Rt. & Lt. Pulm. Arteries$ Pulm. Veins

Relations

In front1. Ant. Thoracic wall separated by ant. margins of both lungs & Pleura2. Below Lt. 4 th costal carti lage pericardium comes in direct contact with Lt. half of lower two pieces of body of sternum3. Before puberty thymus forms ant. Relati on

RelationsBehind

Forms ant. boundary of post. Mediasti numRt and Lt. bronchi Oesophagus, oesophageal plexusDescending thoracic aortaThoracic ductAzygos & Hemiazygos veinsPost. Part of mediasti nal surface of lungs

RelationsOn each side1. Cardiac impression of corresponding lung separated by mediasti nal pleura2. Phrenic nerves and pericadiaco phrenic vessels (Br.of Int.Thoracic a.) between pleura and pericardium

RelationsBelow1. Left lobe of liver and fundus of stomach separated by diaphragm

Serous pericardiumClosed sac Lies within fi brous pericardiumHeart projects into fi brous pericardium From above and behindParietal and visceral layersPotenti al space - capillary layer of fl uid(300 ml max. can be accommodated)

Parietal layerLines inner surface of fi brous Pericardium and blends with it.Visceral layerCovers heart and roots of great vesselsSeparated from myocardium by subserousareolar and fatt y ti ssue

Serous pericardiumConti nuity between parietal & visceral Layers is establishedin the form of two Tubes – One tube surrounds arterial end (Aorta, Pulm. Trunk)- One tube surrounds venous end (Sup. & Inf. Vena cavae 4 pulm. Veins)

Primitive arterial end

Primitive venous end

Transverse SinusPassage between two tubular refl ecti ons of serousPericardiumLined by visceral layer onlyIn front – Ascending aorta & Pulm. TrunkBehind – intra pericardial part of sup.venacavaAbove – bifurcati on of Pulm. TrunkBelow – upper surface of left atrium

Primitive arterial end(Truncus arteriosus)

Primitive venous end

Oblique SinusCul-de-sac behind left atriumClosed on all sides except belowIt lies within the limbs of inverted “J”In front – Left atriumBehind – parietal layer covering post. Of Fib.PericardiumRight side – Rt.Pulm. Veins & Inf.VenacavaLeft side – Left Pulm. VeinsAbove – upper margin of left atrium

Blood supplyFibrous & Parietal layersArterial supplyFibrous & parietal layer – Branches of Int. Thoracic art. - Descending aortaVisceral layer - Coronary arteries

Venous drainageFibrous Parietal layer - Azygos - Int.Thoracic veinsVisceral layer - Coronary sinus

Nerve supply Fibrous & Parietal layers - Phrenic nerveVisceral layer - Vagus & Sympatheti c nerves via coronary plexus

Applied anatomy

Clinical importance of transverse sinusLigature around aorta and pulm. Trunk to controlto control haemorrhage in cardiac surgery

Pericardial tamponade – pericardial eff usion Blood or serous – compresses heart – decreases diastolic capacityParacenti sis of pericardial eff usion - subcostal route (Costo-xyphoid angle 45 deg upward) - Parasternal route (Left 4 th / 5 th interspace close to sternum)

External features

Hollow conical muscular organSituated in mid. Mediasti num

Covered by pericardium

Size of clenched fi st

4 chambers2 atria - interatrial septum2 ventricles – intervent. Sep.

External featuresRt.atrium receives deoxygenated bloodVia Sup. & Inf. venacavae, and coronary sinus.Thru’ Rt. atrioventricular orifi ceTo – Rt. VentricleEjected to Pulm. TrunkTo Pulm. Capillary plexus for oxygenati onPulmonary circulati onTo Left atriumVia 4 pulmonary veinsThru’ Lt. atrioventricular orifi ceTo Left ventricleEjected to ascending aorta forSystemic circulati on

External features MeasurementsApex to base – - 12 cmsAntero-post diameter - 6 cmsWidest transverse diameter 8 to 9 cms(Equal to one half of diameter of thorax)

Weight male – 280 to 340 gms female - 230 to 280 gms

Presenti ng partsApexBase3 surfaces – Sternocostal, diaphragmati c & Left3 borders - Right, Inferior & Left

External features

Apex Conical area formed by left ventricleDirected downwards, forwards and to leftIn 5 th intercostal space 9 cms from midlineSlightly below & medial to left nippleSeparated from ant.thoracic wall byleft lung & pleura

BasePosterior surface – fi xed part of heartQuadrilateral in outlineFormed 2/3rds by post. Surface of left atrium & 1/3 rd by Rt. Atrium

External features

Base

External featuresBoundaries of base

Above Bifurcati on of Pulm. Trunk Below Post. Part of interventricular groove containing coronary sinus & anastomosis of Rt. & Lt. coronary arteries.Rt. Side Rt. Border of Rt. Atrium from sup to Inf. Vena cavaLt. sideLeft border of left atrium from upper to lower Lt. pulm. veins

External features

Features of the Base

SVC opens in upper post part of Rt.atriumIVC opens in lower post part of Rt.atrium

4 Pulm. Veins 2 on each side open in Post. Surface of Lt. atrium

A shallow verti cal inter atrial groovemay be found between 2 atria –Post. Att achment of Inter atrial septum

External featuresRight border

Rounded and convexFormed by Rt. Atrium Extends from Rt. Side of opening ofSVC to IVC

The border separates base fromSternocostal surface

Shallow verti cal groove accpmaniesRt. Border – Sulcus terminalisCorresponds to Crista terminalisin theInterior of Rt. atrium

External features

INCISURA APICIS CORDIS

Inferior Border

SharpSeparates sternocostal from diaphragmati cSurfacesExtends from opening of IVC to apexBorder accompanied by marginal branchof Rt. Coronary artery and veinNotch near apex – Incisura apicis cordisAnt. Interventricular br. of left coronarycurves around it.

External features

Left Border

ILL defi ned convexConvexity to left and upwards

Separates sternocostal from left surface

Extends from left auricle to apex

Accompanied by marginal br. of Lt.coronary artery.

External features

Sterno – costal surface

Directed forwards and upwardsSeparated From base to by Rt. BorderFrom diaphragmati c surface by Inf. BorderFrom Left surface by Left border

Formed byAnt. Surface of Rt. atrium & its auriclePart of ant. Surface of Lt. auricleAnt. Surface of Rt. Ventricle (2/3)Ant. Surface of left ventricle (1/3)

External featuresFeatures of Sterno-Costal Surface

Ant. Part of atrio-ventricular groovePasses downwards & to right betweenRt. Atrium & Rt. Ventricle

Lodges trunk of Rt. Coronary artery

Ant. Interventricular groove passesdownwards parallel to left bordermeets inf. Border at incisura.The groove lodges ant. Interventricularbr. of Lt. coronary artery & great cardiac veinIndicates ant. att achment of interventricular septum

External features

Left

bor

der

Inferior b

order

Right border

Diaphragmatic or Inferior Surface

FlatFace downwards and backwardsFormed only by ventricles2/3 left ventricle & 1/3 rd by Rt. Ventricle

SeparatedFrom Sternocostal surface by inf. BorderFrom the base by the post. Part of Interventricular grooveFrom left surface by less defi ned unnamed border which is backwardConti nuati on of inferior border

External features

Left

bor

der

Inferior b

order

Right border

Features of Inferior Surface

Post. Interventricular groove runs forwardsalong this surface & meets incisura epi.cordis

Groove indicates post. att achment ofInterventricular septum

Groove lodges post. Interventricular br. ofRt. Coronary artery

Middle cardiac vein

Anastomosis of interventricular branches of Both coronary arteries

External features

Left Surface

Directed upwards backwards and to left

Formed mainly by left ventricle andPartly by left atrium & Left auricle

Features

Left part of atrioventricular groove intervenes between Lt. auricle and lt. ventricle

This groove lodges – Trunk and cicumfl ex br. of left cor. art.Terminati on of great cardiac veinCommencement of coronary sinus

Points of observation

Apex formed by left ventricle

Base formed by 2 atria

Rt. Border formed by Rt. Atrium

Diaphragmati c surface formed by 2 ventricles

Base - 2/3 lt. atrium 1/3 Rt. Atrium

Diaphragmati c surface – 2/3 Lt. ventricle, 1/3 Rt. Ventricle

Sternocostal surface – 2/3 Rt. Ventricle 1/3 Lt. ventricle

From midline 2/3 to left of midline, 1/3 to Rt. Of midline

If an elderly in your house suff ers from chest painDo not browse net from your cel to verify which Doctor can diagnose the illness

But; equip yourself with suffi cient Knowledge to save your own kith and kin fi rst.

Only grati tude you can return to your “well-wishers”

And it is the ulti mate pride and their ambiti on