Propanolol Contraindications

A, Hypertension
B, Myocardial infarction
C, Portal Hypertension
D, Diabetes mellitus
E, Angina Pectoris

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Cor pulmonale

   It is defined as right heart failure due to long standing pulmonary hypertension. Which leads to enlargement of the right ventricles and eventually right heart failure ensues.

• This disease also known as Pulmonary haert disease.
• This disease solely caused by primary disorders of respiratory system
• If this disease is chronic then right ventricular hypertrophy develops progressively but in case of acute cor pulmonale right ventricular dilatation may occur due to acute increase pressure instead of hypertrophy.
• Right sided ventricular disease caused by a primarily left sided heart disease or congenital heart disease is not considered as cor pulmonale.
• Almost any chronic lung disease or condition causing prolonged low oxygen blood flow can lead to cor pulmonale

Causes of cor pulmonale:

• Chronic obstructive pulmonary disease ( COPD )***
• Primary pulmonary hypertension***
• Cystic fibrosis
• Interstitial lung disease ( Due to scarring of lung tissue )
• Obstructive sleep apnea
• Recurrent pulmonary embolism ( Chronic blood clots in the lungs)
• Sarcoidosis
• Kyphoscoliosis
• Pneumoconiosis
• Altitude sickness
• Sickle cell anemia
• Loss of lung tissue following lung trauma or surgery

   Acute causes

• Acute massive pulmonary embolism***
• Acute respiratory distress sysndrome ( ARDS )
• Acute exacerbation of cor pulmonale

Mnemonics for causes of Cor pulmonale:   PuLmonary HTN
P = Pulmonary vascular disease

• Primary pulmonary hypertension
• Pulmonary embolism ( Acute massive PE or Chronic recurrent PE )
• Pulmonary vasculitis
• Sickle cell anemia
• ARDS
• Parasite infestation

L = Lung disease

• COPD
• Asthma ( Severe, Chronic)
• Bronchiectasis
• Cystic fibrosis
• Interstitial lung disease
• Loss of lung tissue following lung trauma or surgery
• Sarcoidosis
• Pneumoconiosis

H = Hypoventilation

• Obstructive sleep apnea
• Cerebrovascular disease
• Adenoids enlargements in children

T= Thoracic abnormality

• Kyphosis
• Scoliosis

N = Neuromuscular disease

• Polioymyelitis
• Motor neurone disease
• Myasthenia gravis

Pathophysiology

1, Pumonary vasoconstriction

• Due to respiratory disease and poor lung function can leads to alveolar hypoxia and blood acidemia.
• Alveolar hypoxia and blood acidemia can results in vasoconstriction of pulmonary arteries
• This mechanism leads to pulmonary hypertension and if not treated cor pulmonale ensues

2, Anatomic changes in pulmonary vascular bed

• It occurs secondary to parenchymal lung disease or alveolar lung diseases. e.g Emphysema in COPD, interstitial lung disease, massive pulmonary emobolism, cystic fibrosis.
• This causes increased in pulmonary pressure

3, Hyperviscosity of blood

• Increased blood viscosity is secondary to polycythemia vera ( secondary), sickle cell anemia, macroglobulinemia

4, Increased blood flow in pulmonary vasculature

5, Idiopathic or primary pulmonary hypertension

All above mechanism finally leads to increased pulmonary hypertension and later develop cor pulmonale

Clinical presentation

Symtpoms:

• Shortness of breath ( Initially exertional dyspnea but in severe cases can occurs at rest )
• Wheezing
• Fatigue and syncopal attack
• Chest discomfort with anginal pain due to RV ischemia or pulmonary artery stretching
• Chronic wet cough
• Hemoptysis
• Ascites
• Hepatomegaly and hepatic congestion secondary to right heart failure
• Anorexia due to hepatic involvement
• Right upper quadrant abdominal pain and discomfort due to hepatomegaly and congestion
• Abnormal heart sounds
• Hoarseness of voice due to compression of left recurrent laryngeal nerve by dilated pulmonary artery ( very rare )

Inspection:

• Tachypnea
• Laboured respiratory efforts with retractions of respiratory muscles
• Enlargement of prominent neck and facial veins
• Cyanosis: Bluish dicolouration of face
• Jaundice due to hepatomegaly and congestion

Palpation:

• Hepatomegaly
• Pedal edema

Auscultation:

• Wheezing
• Splitting P2 sound in early stages
• Systolic ejection murmur with sharp ejection click heard in pulmonary area
• Diastolic pulmonary regurgitation
• S3 or S4 sound may be heard
• Systolic murmur of tricuspid regurgitation may be heard

Percussion:

• Hyperresonance sound in case of COPD
• Dull percussion note or fluid thrill in case of ascites

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Jugular Venous Pulse, Pressure and abnormalities

Jugular Venous Pressure is pressure of right atrium. If pressure of right atrial is high then JVP also increase if right atrial pressure is low JVP also low.
- Therefore JVP is determined by right atrial pressure.

Details illustrations about JVP ( Jugular Venous Pulse )

                                                             Click image to enlarge view
a wave = Right atrial contraction ( Atrial systole )
c wave = Transmitted carotid impulse at onset of systole ( Due to bulging of the tricuspid valve ring into the atria during ventricular contraction )
x descent = Right atrial relaxation at ventricular systole ( Onset of atrial relaxation )
v wave= Passive atrial filling during closed tricuspid valve and Venous return
y descent = Passive right ventricular filling at start of ventricular diastole or tricuspid valve opening.



Abnormal JVP waves:

1, Raised JVP with normal waveforms

• Right heart failure
• Volume overload
• Bradycardia

2, Large a wave

• Tricuspid valve stenosis
• Pulmonary hypertension
• Pulmonary valve stenosis

3, Cannon A wave 

It is powerful atrial wave due to contraction of the right atrium against closed tricuspid valve.

• Supraventricular Tachycardia
• Complete heart block without Atrial fibrillation
• AV dissociations ( Atria and ventricles are not conducting appropriate rhythm )
• Ventricular extra systole
• Nodal rhythm
• Pulmonary hypertension
• Tricuspid stenosis

4, Raised JVP with no pulsation

• Superior venacava obstruction

5, Absent a wave

• Atrial fibrillation

6, Kussmaul's sign ( Paradoxical JVP ): Physiologically JVP is rise during expiration and fall during inspiration. But in case of Kussmaul's sign JVP is increases during inspiration. Some conditions are:

• Constrictive pericarditis***
• Pericardial tamponade***
• Pericardial effusion***
• Restrictive cardiomyopathy**
• Tricuspid stenosis
• Right heart failure ( Cor pulmonale )
• Right ventricular infarction

*** = Most common causes

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Calcium Channel Blockers

Rate limiting calcium channel blockers ( Slow CCB )

A, Dihydropyridine (Lipophilic): These are the most potent calcium channel blockers

• Nifedipine


• Amlodipine


• Nimodipine


• Nitrendipine


• Felodipine

B, Phenylalkylamine (Hydrophilic )

• Verapamil

C, Benzothiazepine

• Diltiazem

Mechanism of Action:

1, Smooth Muscle:

• CCB work by blocking Voltage-gated Calcium channels in blood vessels


• This leads to decreases intracellular Ca+ influx resulting in muscle contraction also decreased. 


• Decreased vascular smooth muscle contraction resulting in increased arterial vascular diameter.


• CCB markedly dilate arterial smooth muscle but have a mild effect venous smooth muscle.


• If vasodilation then decrease peripheral vascular resistance..


• CCB are effective against large vessels stiffness which occurs usually in elder patients where there is increased Sytolic BP

2, Heart:

• CCB blocks Voltage-gated Calcium channels which results in decrease cardiac contractlity.


• Decreases in cardiac contractility leads to decreases in cardiac output.


• The 0 phase depolarization in SA and AV nodes is largely Ca+ mediated.


• Verapamil and diltiazem slows sinus rate and AV conduction due to delayed membrane depolarization. This leads to depression of pacemaker and conduction activity i.e. positive chronotropic and dromotropic action.


• Nifedipine doesn't cause delayed membrane depolarization hence it do not decrease SA and AV conduction that is no negative chronotropic and dromotropic action.

-Dihydropyridine are more selective for smooth vascular muscle and negligible -ve inotropic action.
-Diltiazem causes less depression of contractility than verapamil.

CO= Cardiac Output
PVR= Peripheral Vascular Resistance
 
Hence,
        BP= CO x PVR
If there is Decreased CO and Decreased PVR= Decrease BP.

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Mesothelioma

Definition:
  It is very rare form of malignant tumour that develops from the lining of the internal organs known as mesothelium.

Prognosis of mesothelioma is extremely poor.

Causes:
 It is mainly caused by exposure to the Asbestos
Most of mesothelioma patients have worked in asbestos exposed jobs. Frequent exposed to asbestos or inhalation of asbestos particles are very high risk to develop malignant mesothelioma.
Most of cases sign and symptoms doesn't appear until many year even more than decades after the asbestos exposed.
If early mesothelioma detected and managed well have good prognosis.


Types of mesothelioma:

A, Based on the location of Mesothelioma Cancer:

1, Pleural mesothelioma ( Most common site, aprox. 70%)

•      Malignant mesothelioma arises from outer lining of the lungs and internal lining of the chest wall.

2, Peritoneal mesothelioma:

•     Malignant mesothelioma arises from internal lining of the abdominal cavity.

3, Pericardial mesothelioma

•     Malignant mesothelioma arises from pericardial lining of the pericardial sac.

4, Testicular mesothelioma

•    Malignant mesothelioma arises from tunica vaginalis of the testes.

B, Based on the Cell type:

1. Epitheloid mesothelioma ( Most common cell type, approx. 60%, better prognosis)


2. Fibrous or Sarcomatoid


3. Mixed or Biphasic (Both epitheloid and fibrous type)


4. Desmoplastic ( Very rare )

Diagnosis:

• Diagnosis of mesothelioma cancer is very difficult because the symptoms are similar to other medical conditions. It requres qualified mesothelioma doctor. Mesothelioma Doctor start to take all investigation like past medical history, past occupational history like asbestos exposure jobs.


• Chest X- ray: May shows pleural thickening


• Lung function tests should be performed.


• CT scan or MRI should be performed


• Thoracentesis or Chest thoracotomy should be done if there is accumulation of fluid in pleural cavity.


• If ascites: Ascitic tap or paracentesis should be performed.


• If Pericardial: pericardiocentesis should be performed.


• Fluid Cytopathology must be done, even with cytopathology it is very difficult to diagnose mesothelioma


• Biopsy of the affected site must be done to confirm diagnosis of mesothelioma

Treatment:

Prognosis of mesothelioma Cancer is extremely poor.
Qualified Mesothelioma Doctor can only treat mesothelioma patients.

Recently there is some improvements of treatments by newer chemotherapy or multimodality treatments.

Mesothelima at earlier stage has a better prognosis than late stage.

The mainstay of treatment of mesothelioma is

• Surgery: Pneumonectomy, pleurectomy, Decoritcation


• Radiation


• Chemotherapy: Only treatment has proven to improve survival.


• Immunotherapy

   -Mesothelioma treatment is very expensive that's why it require insurance like health insurance, medical insurance and life insurance for treatment expense.
   -If patients had previous jobs which was exposed to asbestos or asbestos related products then it is very easy to lawsuit through  mesothelioma lawyers  to related company for compensation.

More Details : Download this File

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Atrial Fibrillation with rapid ventricular rate

Definition:
 Atrial fibrillation ( AF ) is defined as abnormal irregularly irregular heart rhythm due to rapid, chaotic, asynchronous and incordinated atrial contraction.

Note: always remember 2 point as given below for AF definition,
1, Abnormal irregularly irregular heart rhythm.
2, Rapid, chaotic, asynchronous and incordinated atrial contraction.

In AF, heart rate maybe over 140 beats per minutes.

Types of Atrial fibrillation:
There are three types of atrial fibrillation:

1, Paroxysmal atrial fibrillation

• Rapid heart rate begins suddenly and rapidly and stops spontaneously.


• Do not necessaryly requre treatment if symptos subsides itself.


• If symptoms are persist or troublesome then can use B-blocker and Antiarrhythimic drugs Class IC e.g. Propafenone, Flecainide ( Potent Na+ Channel blockers )


• B-blocker is appropriate if structural heart disease, Hypertension and exertion or stress AF.


• Amiodarone is second line drug


• Digoxin is not effective in case of paroxysmal AF.


• Sometimes radiofrequency ablation may also needed if some forms of paroxysmal AF is not relieved by medications.

2, Persistent Atrial fibrillation

• Rate control and cardioversion are both effective.


• Electrical cardioversion can restore sinus rhythm in case of early AF that is less than 3 months, young patients and no any underlying structural heart disease.


• Frequency of relapse is high i.e. approx. 50% within 1 months and 85% within 1 year.


• If AF is lessa than 48 hours, immediate DC cardioversion is suitable after the IV heparin administration.


• Intravenous Flecainide infusion is safe alternative to Electrical cardioversion if there is no underlying heart disease.


• Anticoagulation should be continued for 6 months or must at least 1 months after cardioversion.


• If relapse again cardioversion is appropriate.


• Antiarrhythmic drugs B-blockers and Amiodarone can reduce risk of recurrence.

3, Permanent Atrial fibrillation

• Rate control is mostly effective treatment.


• Drugs used for rate controls are Digoxin, B-blockers, Rate limiting Calcioum antagonists e.g. Verapamil or diltiazem.


• Controlling rapid heart rate i.e Fast ventricular rate during exercise can be controlled effectively by B-blocker and rate limiting calcium antagonist rather than Digoxin. 


• Additional benifits in patients with Hypertension and structural heart disease if treated with B-blocker and rate limiting CCB. 


• If permanent AF is not controlled by any measure can be treated by inducing complete heart block with transvenous catheter radiofrequency ablation and permanent pacemaker must be implanted at the same time.

Causes of AF:
 -Exact causes of atrial fibrillation is unknown.

Mnemonics for atrial fibrillation:
ATRIAL'S CARDIAC


A = Acute coronary syndrome ( Atherosclerosis or Ischemic heart disease or MI )***
         Amphetamine
T = Thyrotoxicosis
R = Rheumatic heart disease ( Heart Valve disease)***
I  = Idiopathic / Increase BP (HTN)***
A= Alcoholism (Holiday heart)*** / Adrenal disease ( Pheochromocytoma )
L = Lone AF***
        Lung disease ( Acute Pulmonary embolism**, Pneumonia, Emphysema,  COPD, Asthma)
        Lung Cancer
S = Sepsis / Shock / Sick sinus syndrome
        Smoking
        Sleep apnea

C = Congeintal heart disease*** / Congestive heart failure*** /Cardiomyopathy
A = Atrial myxoma
R = Recent heart surgery or Previous heart surgery
D = Diabetes Mellitus
I   = Infections ( sepsis, chest infections )
A = Atrial flutter
C = Carbonmonoxice poisoning / Cocaine / Caffeine

*** = Most Common Causes
Other rare causes:
 Mesothelioma Cancer
 Injury e,g auto mobile accident, road traffic accident, car accident, bike accident.

• Older age get higher risk of developing atrial fibrillation


• If younger patients born with congenital heart disease there is high risk of developing of atrial fibrillation

More Details Download Following File:Mo

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Which cranial nerves are found in the Midbrain (Mesencephalon)?

A, Optic nerve

B, Oculomotor nerve

C, Trochlear nerve

D, Abducens nerve

More details about midbrain:
CLICK ME

Midbrain:
- Embryologically midbrain arises from second vesicles known as mesencephalon of the neural tube
- It is located below the cerebral cortex and above the hindbrain
- It is the smallest and most superior part of brainstem.
- It measures only 1.5 cm.
- It is divided anterior and posterior section by the Aqueduct of Sylvious ( Connects 3rd and 4rth Ventricles)
- It comprises:
        a) Tectum ( Corpora Quaqrigemina )
        b) Tegmentum
        c) Substantia nigra ( Associated with motor system pathways of the basal ganglia )
        d) Cerebral peduncles
        e) Cranial nerves

• Oculomotor nerve responsible for Eye movements and Pupil constriction (Parasympathetic activity).
• Trochlear nerve comes out from the posterior surface of the midrain just below the inferior colliculus.

RED NUCLEUS

Mnemonics: Structures of the midbrain involves visualizing the mesencephalic cross-section as an upside down bear face:-
"The two red nuclei are the eyes of the bear and the cerebellar peduncles are the ears".

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