This document discusses the pharmacotherapy of cardiac arrhythmias. It begins with an overview of cardiac electrophysiology and mechanisms of arrhythmias. It then classifies antiarrhythmic drugs and discusses their mechanisms and uses for treating various arrhythmias. The document focuses on sodium channel blockers, beta blockers, and drugs that prolong the action potential. It provides details on specific drugs like quinidine, amiodarone, and sotalol.
What are anti-coagulants?
What are the difference between antiplatelet, anticoagulants and thrombolytics?
Coagulation cascade
Virchows Triad
Classification of anti-coagulants?
Indications of anti-coagulants?
Mechanism and site of action of different anti-coagulants?
Please find the power point on Pharmacology of Anticoagulants, antiplatelets . I tried to present it on understandable way and all the contents are reviewed by experts and from very reliable references. Thank you
What are anti-coagulants?
What are the difference between antiplatelet, anticoagulants and thrombolytics?
Coagulation cascade
Virchows Triad
Classification of anti-coagulants?
Indications of anti-coagulants?
Mechanism and site of action of different anti-coagulants?
Please find the power point on Pharmacology of Anticoagulants, antiplatelets . I tried to present it on understandable way and all the contents are reviewed by experts and from very reliable references. Thank you
263778731218 Abortion Clinic /Pills In Harare ,sisternakatoto
263778731218 Abortion Clinic /Pills In Harare ,ABORTION WOMEN’S CLINIC +27730423979 IN women clinic we believe that every woman should be able to make choices in her pregnancy. Our job is to provide compassionate care, safety,affordable and confidential services. That’s why we have won the trust from all generations of women all over the world. we use non surgical method(Abortion pills) to terminate…Dr.LISA +27730423979women Clinic is committed to providing the highest quality of obstetrical and gynecological care to women of all ages. Our dedicated staff aim to treat each patient and her health concerns with compassion and respect.Our dedicated group ABORTION WOMEN’S CLINIC +27730423979 IN women clinic we believe that every woman should be able to make choices in her pregnancy. Our job is to provide compassionate care, safety,affordable and confidential services. That’s why we have won the trust from all generations of women all over the world. we use non surgical method(Abortion pills) to terminate…Dr.LISA +27730423979women Clinic is committed to providing the highest quality of obstetrical and gynecological care to women of all ages. Our dedicated staff aim to treat each patient and her health concerns with compassion and respect.Our dedicated group of receptionists, nurses, and physicians have worked together as a teamof receptionists, nurses, and physicians have worked together as a team wwww.lisywomensclinic.co.za/
Lung Cancer: Artificial Intelligence, Synergetics, Complex System Analysis, S...Oleg Kshivets
RESULTS: Overall life span (LS) was 2252.1±1742.5 days and cumulative 5-year survival (5YS) reached 73.2%, 10 years – 64.8%, 20 years – 42.5%. 513 LCP lived more than 5 years (LS=3124.6±1525.6 days), 148 LCP – more than 10 years (LS=5054.4±1504.1 days).199 LCP died because of LC (LS=562.7±374.5 days). 5YS of LCP after bi/lobectomies was significantly superior in comparison with LCP after pneumonectomies (78.1% vs.63.7%, P=0.00001 by log-rank test). AT significantly improved 5YS (66.3% vs. 34.8%) (P=0.00000 by log-rank test) only for LCP with N1-2. Cox modeling displayed that 5YS of LCP significantly depended on: phase transition (PT) early-invasive LC in terms of synergetics, PT N0—N12, cell ratio factors (ratio between cancer cells- CC and blood cells subpopulations), G1-3, histology, glucose, AT, blood cell circuit, prothrombin index, heparin tolerance, recalcification time (P=0.000-0.038). Neural networks, genetic algorithm selection and bootstrap simulation revealed relationships between 5YS and PT early-invasive LC (rank=1), PT N0—N12 (rank=2), thrombocytes/CC (3), erythrocytes/CC (4), eosinophils/CC (5), healthy cells/CC (6), lymphocytes/CC (7), segmented neutrophils/CC (8), stick neutrophils/CC (9), monocytes/CC (10); leucocytes/CC (11). Correct prediction of 5YS was 100% by neural networks computing (area under ROC curve=1.0; error=0.0).
CONCLUSIONS: 5YS of LCP after radical procedures significantly depended on: 1) PT early-invasive cancer; 2) PT N0--N12; 3) cell ratio factors; 4) blood cell circuit; 5) biochemical factors; 6) hemostasis system; 7) AT; 8) LC characteristics; 9) LC cell dynamics; 10) surgery type: lobectomy/pneumonectomy; 11) anthropometric data. Optimal diagnosis and treatment strategies for LC are: 1) screening and early detection of LC; 2) availability of experienced thoracic surgeons because of complexity of radical procedures; 3) aggressive en block surgery and adequate lymph node dissection for completeness; 4) precise prediction; 5) adjuvant chemoimmunoradiotherapy for LCP with unfavorable prognosis.
Title: Sense of Smell
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the primary categories of smells and the concept of odor blindness.
Explain the structure and location of the olfactory membrane and mucosa, including the types and roles of cells involved in olfaction.
Describe the pathway and mechanisms of olfactory signal transmission from the olfactory receptors to the brain.
Illustrate the biochemical cascade triggered by odorant binding to olfactory receptors, including the role of G-proteins and second messengers in generating an action potential.
Identify different types of olfactory disorders such as anosmia, hyposmia, hyperosmia, and dysosmia, including their potential causes.
Key Topics:
Olfactory Genes:
3% of the human genome accounts for olfactory genes.
400 genes for odorant receptors.
Olfactory Membrane:
Located in the superior part of the nasal cavity.
Medially: Folds downward along the superior septum.
Laterally: Folds over the superior turbinate and upper surface of the middle turbinate.
Total surface area: 5-10 square centimeters.
Olfactory Mucosa:
Olfactory Cells: Bipolar nerve cells derived from the CNS (100 million), with 4-25 olfactory cilia per cell.
Sustentacular Cells: Produce mucus and maintain ionic and molecular environment.
Basal Cells: Replace worn-out olfactory cells with an average lifespan of 1-2 months.
Bowman’s Gland: Secretes mucus.
Stimulation of Olfactory Cells:
Odorant dissolves in mucus and attaches to receptors on olfactory cilia.
Involves a cascade effect through G-proteins and second messengers, leading to depolarization and action potential generation in the olfactory nerve.
Quality of a Good Odorant:
Small (3-20 Carbon atoms), volatile, water-soluble, and lipid-soluble.
Facilitated by odorant-binding proteins in mucus.
Membrane Potential and Action Potential:
Resting membrane potential: -55mV.
Action potential frequency in the olfactory nerve increases with odorant strength.
Adaptation Towards the Sense of Smell:
Rapid adaptation within the first second, with further slow adaptation.
Psychological adaptation greater than receptor adaptation, involving feedback inhibition from the central nervous system.
Primary Sensations of Smell:
Camphoraceous, Musky, Floral, Pepperminty, Ethereal, Pungent, Putrid.
Odor Detection Threshold:
Examples: Hydrogen sulfide (0.0005 ppm), Methyl-mercaptan (0.002 ppm).
Some toxic substances are odorless at lethal concentrations.
Characteristics of Smell:
Odor blindness for single substances due to lack of appropriate receptor protein.
Behavioral and emotional influences of smell.
Transmission of Olfactory Signals:
From olfactory cells to glomeruli in the olfactory bulb, involving lateral inhibition.
Primitive, less old, and new olfactory systems with different path
Couples presenting to the infertility clinic- Do they really have infertility...Sujoy Dasgupta
Dr Sujoy Dasgupta presented the study on "Couples presenting to the infertility clinic- Do they really have infertility? – The unexplored stories of non-consummation" in the 13th Congress of the Asia Pacific Initiative on Reproduction (ASPIRE 2024) at Manila on 24 May, 2024.
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Ve...kevinkariuki227
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Verified Chapters 1 - 19, Complete Newest Version.pdf
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Verified Chapters 1 - 19, Complete Newest Version.pdf
New Directions in Targeted Therapeutic Approaches for Older Adults With Mantl...i3 Health
i3 Health is pleased to make the speaker slides from this activity available for use as a non-accredited self-study or teaching resource.
This slide deck presented by Dr. Kami Maddocks, Professor-Clinical in the Division of Hematology and
Associate Division Director for Ambulatory Operations
The Ohio State University Comprehensive Cancer Center, will provide insight into new directions in targeted therapeutic approaches for older adults with mantle cell lymphoma.
STATEMENT OF NEED
Mantle cell lymphoma (MCL) is a rare, aggressive B-cell non-Hodgkin lymphoma (NHL) accounting for 5% to 7% of all lymphomas. Its prognosis ranges from indolent disease that does not require treatment for years to very aggressive disease, which is associated with poor survival (Silkenstedt et al, 2021). Typically, MCL is diagnosed at advanced stage and in older patients who cannot tolerate intensive therapy (NCCN, 2022). Although recent advances have slightly increased remission rates, recurrence and relapse remain very common, leading to a median overall survival between 3 and 6 years (LLS, 2021). Though there are several effective options, progress is still needed towards establishing an accepted frontline approach for MCL (Castellino et al, 2022). Treatment selection and management of MCL are complicated by the heterogeneity of prognosis, advanced age and comorbidities of patients, and lack of an established standard approach for treatment, making it vital that clinicians be familiar with the latest research and advances in this area. In this activity chaired by Michael Wang, MD, Professor in the Department of Lymphoma & Myeloma at MD Anderson Cancer Center, expert faculty will discuss prognostic factors informing treatment, the promising results of recent trials in new therapeutic approaches, and the implications of treatment resistance in therapeutic selection for MCL.
Target Audience
Hematology/oncology fellows, attending faculty, and other health care professionals involved in the treatment of patients with mantle cell lymphoma (MCL).
Learning Objectives
1.) Identify clinical and biological prognostic factors that can guide treatment decision making for older adults with MCL
2.) Evaluate emerging data on targeted therapeutic approaches for treatment-naive and relapsed/refractory MCL and their applicability to older adults
3.) Assess mechanisms of resistance to targeted therapies for MCL and their implications for treatment selection
HOT NEW PRODUCT! BIG SALES FAST SHIPPING NOW FROM CHINA!! EU KU DB BK substit...GL Anaacs
Contact us if you are interested:
Email / Skype : kefaya1771@gmail.com
Threema: PXHY5PDH
New BATCH Ku !!! MUCH IN DEMAND FAST SALE EVERY BATCH HAPPY GOOD EFFECT BIG BATCH !
Contact me on Threema or skype to start big business!!
Hot-sale products:
NEW HOT EUTYLONE WHITE CRYSTAL!!
5cl-adba precursor (semi finished )
5cl-adba raw materials
ADBB precursor (semi finished )
ADBB raw materials
APVP powder
5fadb/4f-adb
Jwh018 / Jwh210
Eutylone crystal
Protonitazene (hydrochloride) CAS: 119276-01-6
Flubrotizolam CAS: 57801-95-3
Metonitazene CAS: 14680-51-4
Payment terms: Western Union,MoneyGram,Bitcoin or USDT.
Deliver Time: Usually 7-15days
Shipping method: FedEx, TNT, DHL,UPS etc.Our deliveries are 100% safe, fast, reliable and discreet.
Samples will be sent for your evaluation!If you are interested in, please contact me, let's talk details.
We specializes in exporting high quality Research chemical, medical intermediate, Pharmaceutical chemicals and so on. Products are exported to USA, Canada, France, Korea, Japan,Russia, Southeast Asia and other countries.
Flu Vaccine Alert in Bangalore Karnatakaaddon Scans
As flu season approaches, health officials in Bangalore, Karnataka, are urging residents to get their flu vaccinations. The seasonal flu, while common, can lead to severe health complications, particularly for vulnerable populations such as young children, the elderly, and those with underlying health conditions.
Dr. Vidisha Kumari, a leading epidemiologist in Bangalore, emphasizes the importance of getting vaccinated. "The flu vaccine is our best defense against the influenza virus. It not only protects individuals but also helps prevent the spread of the virus in our communities," he says.
This year, the flu season is expected to coincide with a potential increase in other respiratory illnesses. The Karnataka Health Department has launched an awareness campaign highlighting the significance of flu vaccinations. They have set up multiple vaccination centers across Bangalore, making it convenient for residents to receive their shots.
To encourage widespread vaccination, the government is also collaborating with local schools, workplaces, and community centers to facilitate vaccination drives. Special attention is being given to ensuring that the vaccine is accessible to all, including marginalized communities who may have limited access to healthcare.
Residents are reminded that the flu vaccine is safe and effective. Common side effects are mild and may include soreness at the injection site, mild fever, or muscle aches. These side effects are generally short-lived and far less severe than the flu itself.
Healthcare providers are also stressing the importance of continuing COVID-19 precautions. Wearing masks, practicing good hand hygiene, and maintaining social distancing are still crucial, especially in crowded places.
Protect yourself and your loved ones by getting vaccinated. Together, we can help keep Bangalore healthy and safe this flu season. For more information on vaccination centers and schedules, residents can visit the Karnataka Health Department’s official website or follow their social media pages.
Stay informed, stay safe, and get your flu shot today!
Pulmonary Thromboembolism - etilogy, types, medical- Surgical and nursing man...VarunMahajani
Disruption of blood supply to lung alveoli due to blockage of one or more pulmonary blood vessels is called as Pulmonary thromboembolism. In this presentation we will discuss its causes, types and its management in depth.
2. Overview
• Electrophysiology of cardiac rhythm
• Mechanisms in cardiac arrhythmia
• Classification of anti-arrhythmic drugs
• Treatment of individual arrhythmias
• Summary
Page 2 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
3. Electrophysiology of cardiac rhythm
Page 3 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
4. Fast & Slow channel AP
Page 4 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
5. Mechanism of Cardiac arrhythmias
• Abnormal impulse generation
• After-depolarization
• Delayed after-depolarization (DAD)
• Early after-depolarization (EAD)
• Abnormal impulse conduction
• Conduction block
• Re-entry phenomenon (Circus movement of rhythm)
• Accessory tract pathway
Page 5 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
6. Abnormal impulse generation
• Depressed automaticity SA node – escape beat & ↓ HR
• Enhanced automaticity SA node - ↑ HR
• AV node , Purkinje fibres, atrial & ventricular cells:
spontaneous diastolic depolarisation & repetitive firing –
RMP - 60 mV
AV nodal rhythm,
idioventricular rhythm or
ectopic beats
Page 6 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
7. Ectopic activity is encouraged by-
• Faster phase 4 depolarisation
• Less negative resting membrane
potential (RMP)
• More negative threshold potential
Page 7 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
8. After depolarisation
Normal action potential (AP) triggers
extra-abnormal depolarisation
Abnormal Ca2+ influx into cardiac myocyte
during or immediately after phase 3 of
ventricular AP
Page 8 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
9. Page 9 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
10. Abnormal impulse conduction
A. Conduction block:
• Dropped beat or idioventricular rhythm
• Severely depressed conduction
Page 10 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
11. B. Re-entry phenomenon:
• 80 – 90 % Clinical arrhythmia
• Re-entrant arrhythmias
Premature beat, paroxysmal supraventricular
tachycardia (PSVT), atrial flutter (AFL) &
ventricular fibrillation (VF)
Page 11 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
12. Circus movement of rhythm & accessory
tract pathway
Page 12 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
13. Functional re-entry
• Functional obstacle and unidirectional conduction pathway
is created by a premature impulse
• On encountering refractory tissue in one direction,
wavefront travels through partially recovered fibres—gets
markedly slowed and can set up small re-entry circuits
which may constantly shift location
Ventricular extrasystoles,
polymorphic ventricular tachycardia,
Atrial / Ventricular Fibrillation
Page 13 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
14. Fractionation of impulse
• When atrial ERP is brief and inhomogeneous, an impulse
generated early in diastole gets conducted irregularly over
the atrium, slowly through fibres with longer ERP (partially
recovered) and not at all through those still refractory
• Asynchronous activation of atrial fibres→ atrial fibrillation
Page 14 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
15. Classification
I. Membrane stabilizing agents (Na+ channel blockers):
A. Quinidine, Procainamide, Disopyramide
B. Lidocaine, Mexiletine
C. Propafenone, Flecainide
II. Antiadrenergic agents (β blockers): Propranolol,
Esmolol, Sotalol
III. Agents widening AP: Amiodarone, Dronedarone
Dofetilide, Ibutilide
IV. Calcium channel blockers: Verapamil, Diltiazem
Page 15 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
16. In addition
1. For PSVT : Adenosine, Digoxin
2. For A-V block : Sympathomimetics - Isoprenaline
Anticholinergics - Atropine
3. Digitalis: AF, AFL and PSVT to control ventricular rate
Page 16 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
17. Class I
• Division: interaction with cardiac Na+ channel &
effect on different phases of cardiac AP
Binds to Na+ channel more strongly when they
are in activated or inactivated state
USE DEPENDENCE
Block high frequency excitation of myocardium without
preventing heart from beating at normal frequency
Page 17 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
18. Class IA
• Mechanism of action (MoA):
• Extinguish ectopic pacemaker & abolish re-entry by
converting unidirectional block into bidirectional block
Blocks activated Na+ channels > inactivated
channel & slow rate of dissociation
(recovery time 1-10 sec)
Page 18 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
19. Quinidine
• Also has anti-vagal action
• Depresses myocardial contractility
• ECG - ↑ PR & QT interval & broaden QRS complex
• Side effect –
• Rise in blood levels & toxicity of digoxin
• Dose – 200-400 mg TDS orally
Diarrhoea (MC)
Quinidine syncope
Cinchonism
Page 19 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
20. Procainamide
• Cardiac electrophysiological action is almost identical to
that of quinidine
• Differences are:
• Long term high dose therapy – SLE
•Less effective in suppressing ectopic automaticity
•Less marked depression of contractility & AV
conduction
•No anti-vagal action
•No α blocking activity
•Doesn’t alter plasma levels of digoxin
Page 20 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
21. • Dose:
• Uses:
Abolition of arrhythmia:
500 mg iv loading dose (25 mg/min inj.) f/b 2 mg/kg/hr
Or
500 mg oral / im f/b 250-500 mg every 2 hrs
Maintenance dose:
500 mg every 4-6 hrs
To terminate VT & some
supraventricular arrhythmia
Many WPW reciprocal VTs respond
& to prevent recurrence of VF
Page 21 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
22. Disopyramide
• Prominent cardiac depressant & anti-cholinergic action
• No interaction with digoxin
• Longer T1/2 (6-8 hrs)
• Side effects – anti-cholinergic are most prominent
• Dose – 100-150 mg 6-8 hrly oral
• Uses – 2nd
line drug for prevention of recurrence of
ventricular arrhythmia
Page 22 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
23. Class IB
• Mechanism of action (MoA):
• Like quinidine, also abolish ventricular re-entry
tachycardia
• Block inactivated > activated Na+ channels & rapid
rate of association & dissociation
• Do not delay channel recovery (recovery time < 1 sec)
• Block Na+ channels more in diseased myocardium
Page 23 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
24. Lidocaine
• Most prominent action –
• Inactive orally due to high first pass metabolism
• Action of IV bolus lasts only 10-20 mins
1. Suppression of automaticity in ectopic foci
2. ↓ APD in Purkinje Fibres (PF) & ventricular muscles
Suppresses re-entrant ventricular arrhythmia either by
abolishing 1 way block or producing 2 way block
Page 24 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
25. • T1/2:
Early distribution phase – 8 mins
Later elimination phase – 2 hrs
• Dose:
50-100 mg iv bolus f/b 20-40 mg every 10-20 min
(Max 300 mg in 1 hr)
Or
1-3 mg/min infusion
• S/E: Dose related neurological effects
• No proarrhythmic potential & least cardiotoxic
Page 25 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
26. Mexiletine
• Local anaesthetic & orally active
• Automaticity in PF is ↓ by both ↓ phase 4 & ↑ threshold
voltage
• By ↓ rate of 0 phase depolarisation in ischemic PF, converts
1 way block into 2 way block
• Tremors – early sign of toxicity
Bradycardia, hypotension & accentuation of AV block – iv
• T1/2 – 9-12 hrs
Page 26 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
27. • Dose:
100-250 mg iv over 10 mins, 1mg/min infusion
Oral 150-200 mg TDS with meals
• Use:
Post MI ventricular arrhythmia as alternative to lidocaine
Page 27 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
28. Class IC
• Mechanism of action (MoA):
• High proarrhythmic potential when administered chronically
• Markedly ↓ rate of phase 0 depolarisation in Purkinje &
ventricular myocardial fibres
• ↓ automaticity, ↓ AV conduction & contractility
• Retard re-entry of retrograde & anterograde impulses
• Prominent depressant action on normal heart as well
Most potent Na+ channel blocker with more prominent
action on open state & longest recovery time (> 10 sec)
Page 28 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
29. Flecainide
• Prototype drug which markedly delays Na+ channel recovery
• No consistent effect on APD & no β blocking activity
• CAST study, ↑ mortality in patients recovering from MI
• Provokes arrhythmias during chronic therapy
Highest proarrhythmic potential
Page 29 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
30. Propafenone
• By blocking Na+ channels, depresses impulse
transmission & has profound effect on His-Purkinje as well
as accessory pathway conduction
• Anterograde & retrograde conduction in bypass tract
of WPW syndrome is retarded
• Prolongs APD & has β blocking property – can precipitate
CHF & bronchospasm
• Bioavailability & T1/2 differ considerably among individuals
Page 30 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
31. • Side effects:
Proarrhythmic events
• Dose:
150 mg BD – 300 mg TDS
• Use:
Prophylaxis & treatment of ventricular arrhythmias, re-
entrant tachycardia involving AV node / accessory
pathway & to maintain sinus rhythm in AF
↑ ventricular rate in atrial flutter by slowing atrial rate &
allowing 1:1 AV transmission
Page 31 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
32. Class II
• Mechanism of action (MoA):
• Slows sinus & AV nodal conduction which result in ↓ in
HR & prolongation in PR interval
• QT & QRS interval are not altered significantly
β blockers that competitively block catecholamine
induced stimulation of cardiac β receptors & depress
phase 4 depolarisation of pacemaker cells
Page 32 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
33. Propranolol
• Marked ↓ in slope of phase 4 depolarisation &
automaticity occur in SA node, PF & other ectopic foci
when same has ↑ under adrenergic influence
• ECG: Prolonged PR interval
• Dose:
Rapid action: Slow iv infusion 1-3 mg/min in 50 ml of
5% glucose solution (max 5 mg)
Oral: 40-80 mg TDS
For resistant ventricular arrhythmias - ~1000 mg
Page 33 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
34. • Uses:
Inappropriate sinus tachycardia
AES / VES, especially provoked by emotion or exercise
Prevent recurrences of PSVT
Recurrence of VT
Terminate torsades de pointes
Page 34 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
35. Esmolol
• Quick & short acting β1 blocker administered IV for
emergency control of ventricular rate in AF / AFL
• Terminate supraventricular tachycardia
• Sympathetically mediated arrhythmias seen in
pheochromocytoma & anaesthesia with halothane
• Dose:
Loading dose of 0.5 mg/kg in 1 min followed by 0.05–0.2
mg/kg/min i.v. infusion.
Page 35 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
36. Sotalol
• Prominent class III action of prolonging repolarisation by
blocking cardiac inward rectifier K+ channel
• Non-selective β blocker & effect is exhibited at doses
below than that required for prolongation of APD
Both Class II & III action
• Limitation: Prolongation of APD & QT, risk of dose
dependent torsade de pointes
• Dose: 80 mg BD orally
Page 36 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
37. Class III
• Mechanism of action:
• Prolong ERP
• QT & PR interval are prolonged
• Tissue remains refractory even after full repolarisation
Re-entrant arrhythmias are terminated
Prolongation of repolarisation by blocking outward
K+ channel during phase 3 of AP
Page 37 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
38. Amiodarone
• Iodine containing, highly lipophilic, long acting
• Conduction is slowed & ectopic automaticity is markedly
depressed, but that of SA node is only slightly affected
• Despite prolongation of APD, arrhythmia provoking
potential of amiodarone is low
Blocks Na+ channels
Mild β blocking activity
Ca2+ blocking action
Page 38 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
39. • Incompletely & slowly absorbed from GIT
On daily oral ingestion, action develops over several days
On IV injection, action develops rapidly
• Duration of action is exceptionally long; t1/2 – 3-8 weeks
• Side effects:
1. Pulmonary alveolitis & fibrosis – most serious
2. Hypotension, bradycardia & myocardial depression
– on IV injection & after drug accumulation
3. Corneal microdeposits
4. Photosensitisation & sun burn like pigmentation
Page 39 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
40. • Uses:
• Dose:
1. Resistant VT & recurrent VF
2. Maintain sinus rhythm in AF when other drugs have failed
3. Rapid termination of VT & VF and supraventricular
arrhythmia – IV injection
4. WPW tachyarrhythmia is terminated by suppression of
both normal & aberrant pathway
1. Orally 400–600 mg/day for few weeks, followed by
100–200 mg OD for maintenance therapy
2. Loading dose – 150 mg IV rapid infusion over 10
min f/b slow infusion of 1 mg/min for 6 hrs then
maintenance infusion of 0.5 mg/min for 24 hrs
Page 40 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
41. Dronedarone
• Amiodarone like drug without iodine atoms
• Shorter t1/2 – 1-2 days
• Dose:
400 mg BD orally
• Use:
Prevent recurrence in patients with persistent AF
Page 41 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
42. Bretylium
• Given only in ICU facility for treating refractory life-
threatening ventricular tachycardia & fibrillation
• Also known as Chemical / Pharmacological defibrillator
• Ventricular fibrillation: 5 mg/kg by rapid IV inj. &
repeated every 15-30 mins
• Side effects: Postural hypotension
Page 42 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
43. Dofetilide
• Pure Class III drug
• Prolongs APD & ERP by selectively blocking rapid
components of delayed rectifier K+ current
• Converts AF / AFL to sinus rhythm in ~30%; but more
effective in maintaining sinus rhythm in converted
patients
• Dose: 0.5 mg BD orally
Page 43 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
44. Vernakalant
• Mixed Na+ & K+ channel blocker
• Prolong atrial ERP & slows conduction through AV node
• Association & dissociation with Na+ channels is faster,
thus more effective in myocytes firing more rapidly
• Use:
Treatment of AF
• Dose:
IV infusion 3 mg/kg over 10 min then 2 mg/kg over 15 min
Page 44 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
45. Azimilide
• Blocks both slow & rapid components of K+ channels
• Low incidence of torsades de pointes
• Under trial to convert AF into sinus rhythm
Page 45 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
46. Tedisamil
• Upcoming Class III drug
• Given by IV infusion
• For conversion of AF & AFL to sinus rhythm
Page 46 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
47. Class IV
• Mechanism of action:
Blocks both activated & inactivated L-type Ca2+
channels in myocardium
↓ in rate of depolarisation (phase 4) in SA & AV
node
& slowed conduction through AV node
↑ in PR interval & ERP
Page 47 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
48. Verapamil
• Most prominent cardiac electrophysiological action
• Basic action is to depress Ca2+ mediated depolarization.
This suppresses automaticity and re-entry dependent on
slow channel response
• Most consistent action - prolongation of A-V nodal ERP
• Uses:
1. PSVT –
Terminate attack:- 5 mg IV over 2-3 min
Prevent recurrence:- 60-120 mg TDS orally
Page 48 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
49. 2. To control ventricular rate in AF or AFL:
Dose dependent (40–120 mg TDS oral) reduction in
ventricular rate in AF and AFl, and is a first line drug
Injected i.v. for emergency control of ventricular rate in
AF and AFL (5-10 mg/hr IV infusion)
3. Re-entrant supraventricular and nodal arrhythmias
are susceptible to verapamil, but it is contraindicated in
broad QRS complex WPW tachycardia
Page 49 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
50. Diltiazem
• Alternative to verapamil – termination & prophylaxis of
PSVT
• For rapid control of ventricular rate in AF or AFL -
i.v. diltiazem is preferred over verapamil, because
• Dose: 5-15 mg/hr continuous infusion till adequate response
1. more easily titrated to the target heart rate
2. causes less hypotension or myocardial depression
3. used even in the presence of mild-to-moderate CHF
Page 50 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
51. Adenosine
Stimulates adenosine receptors (A1)
Opens G-protein coupled K+ channel & inhibits SA
nodal, atrial & AV nodal conduction
• Terminates re-entrant circuit through AV node & restores
normal sinus rhythm in PSVT
• Administered by rapid i.v. injection (over 1–3 sec) either
as the free base (6–12 mg) or as ATP (10–20 mg),
terminates within 30 sec. >90% episodes
of PSVT involving A-V node
Page 51 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
52. • very short t½ in blood (~10 sec)
• Advantages of adenosine for termination of PSVT are:
1. Efficacy equivalent to or better than verapamil.
2. Action lasts < 1 min; adverse effects are transient.
3. No haemodynamic deterioration; can be given to patients
with hypotension, CHF or on β blockers
4. Safe in wide QRS tachycardia
5. Effective in patients not responding to verapamil
Page 52 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
53. • Main side effects:
Facial flushing, shortness of breath, bronchospasm,
nausea, metallic taste
• Other uses of adenosine:
(a) Diagnosis of tachycardia dependent on A-V node
(b) To induce brief coronary vasodilatation during
certain
diagnostic/interventional procedures
(c) To produce controlled hypotension during surgery
Page 53 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
54. Atrial / Ventricular extrasystole
• Asymptomatic – no treatment required
• Symptomatic - β blocker
Page 54 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
55. Atrial fibrillation
• Definition:
Fast ectopic, irregular atrial activity (350-600 bpm)
• Ventricular rate ~ 100-150 bpm
• Treatment:
1. Underlying heart disease – find out cause
2. Rate control – 70-100 bpm
β blocker:- esmolol Acute therapy
CCB:- verapamil
Digoxin Chronic therapy
Page 55 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
56. 3. Rhythm control:
Electrical
Acute therapy – DC shock
Chronic therapy – Amiodarone
Pharmacological
Acute therapy – Amiodarone
IV
Chronic therapy – Amiodarone
Propafenone
Page 56 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
57. Acute AF (> 48 hours)
Transesophageal echocardiography
Yes No
Don’t cardiovert immediately Immediate cardioversion
Warfarin for 3 weeks
Cardioversion
Warfarin for 4 weeks
Page 57 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
58. Chronic AF (>6 months)
a. Rate control with β blocker, CCB & Digoxin
b. ↓ Risk of ischemic stroke
Aspirin / Warfarin based on CHADS 2 score
If score ≥2 – warfarin
<2 – aspirin
Page 58 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
59. Atrial flutter
• Atrial rate 250-350 bpm
• Ventricular rate 75-175 bpm
• TOC – DC shock
• Recurrent atrial flutter:
A. Radiofrequency ablation (Elective procedure)
B. Digoxin
Atrial flutter Atrial fibrillation
Page 59 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
60. Wolf-Parkinson-White Syndrome
Tachycardia
• Termination:
Cardioversion, Radiofrequency ablation
• Maintenance:
1. Narrow QRS - Propafenone/procainamide
2. Wide QRS - Propafenone + verapamil / propranolol
or Amiodarone / sotalol
Page 60 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
61. PSVT
• An attack of PSVT can be terminated by reflex vagal
stimulation through
• Alternatively, or if it does not work, the drug of choice is
adenosine (i.v.). Other alternatives are i.v. injection of
verapamil / diltiazem / esmolol.
• Prevent recurrences - oral therapy with verapamil,
diltiazem or propranolol alone or combined with digoxin
TOC – Radiofrequency ablation
1. Valsalva maneuver,
2. Splashing ice cold water on face,
3. Hyperflexion (head between knees), etc.
Page 61 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
62. Ventricular tachycardia
• Definition:
≥ 4 consecutive ventricular extrasystole of > 100 bpm
• Unstable VT:
Immediate DC shock
Amiodarone (DOC) / Lidocaine / procainamide (IV)
• Prevention of recurrence / sudden cardiac death:
Best method – Intracardiac defibrillator
Alternative – Amiodarone / Propranolol / Propafenone
Page 62 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
63. Chronic ventricular tachycardia
• Nonsustained VT:
Suppression - Propranolol/amiodarone (oral)
• Sustained VT:
• Abolition - i.v. Amiodarone + propranolol
or cardioversion
or propafenone / lidocaine (i.v.)
• Maintenance therapy - Amiodarone/sotalol
(prevention of VF/arrest) Implantable defibrillator
Page 63 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
64. Ventricular fibrillation
• Grossly irregular, rapid & fractionated activation of
ventricles resulting in inco-ordinated contraction of
its fibres with loss of pumping action
• Termination:
Defibrillation + amiodarone (i.v.)
• Recurrence prevention:
Amiodarone (oral) / propranolol
Page 64 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
65. Bradyarrhythmias
• Results from failure of impulse generation within SA node
or
failure of impulse conduction through AV node
• Atrio-ventricular (A-V) block is due to depression of
impulse conduction through A-V node and bundle of His,
mostly due to vagal influence or ischaemia.
• First degree A-V block: Slowed conduction resulting in
prolonged P-R interval
Page 65 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
66. • Second degree A-V block: Some supraventricular
complexes are not conducted: drop beats
• Third degree A-V block: No supraventricular complexes
are conducted; ventricle generates its own impulse;
complete heart block
• Definitive treatment - pacing with cardiac pacemaker
• Drugs are of value only for acute/transient A-V block and
as an interim measure.
• Atropine: When A-V block is due to vagal overactivity, it
can be improved by atropine 0.6–1.2 mg i.m.
Page 66 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
67. • Sympathomimetics (isoprenaline): Overcome partial
heart block by facilitating A-V conduction and shortening
ERP of conducting tissues.
Also used in complete (3rd
degree) heart block to
maintain a sufficient idioventricular rate till external
pacemaker can be implanted
Page 67 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
68. Summary
• Abnormal automaticity or impaired conduction or both
underlies cardiac arrhythmia
• Anti-arrhythmic drugs used to prevent or treat irregularities
of cardiac rate & rhythm
• Anti-arrhythmic drugs themselves, may cause arrhythmias
by altering electrophysiological properties of cardiac fibres
• Asymptomatic atrial / ventricular extrasystole need not be
treated
• Ventricular arrhythmias are most important cause of
sudden cardiac death. Therefore, should be monitored
& treated in intensive coronary care unit
Page 68 of 68 Pharmacotherapy of cardiac arrhythmias – Dr. Vikas S. Sharma
16.02.2016
69. References
• Goodman & Gilman’s The Pharmacological Basis of
Therapeutics 12th
Edition
• Longo, Fauci, Kasper, Hauser, Jameson and Loscalzo.
Harrisons’s Principles of Internal Medicine. 19th
Edition
• Rang & Dales’s Pharmacology 7th
Edition
• H. L. Sharma & K. K. Sharma’s Principles of Pharmacology 2nd
Edition
• Lippincott Illustrated Reviews: Pharmacology 6th
Edition