Cardiac Drug Update. By Pamela P. Bayles, RN, BSN

Transcription

1 Cardiac Drug Update By Pamela P. Bayles, RN, BSN

2 Advances in cardiovascular medicine over the last decade have dwarfed the major advances throughout all of history Advances over the last ten years have resulted in a 25% decrease in deaths due to CAD This is by and large due to the advances in cardiac pharmacology

3 Statins Cholesterol lowering by increasing clearance of LDL from bloodstream Cause moderate reduction in triglyceride levels Cause small increase in levels of HDL Results can be seen after one week and effect maximal after 4-6 weeks Also reduce size of plaques in arteries, stabilize plaques and reduce inflammation which is am important component of plaque formation and rupture

4 Reduces C. Reactive Protein levels Decreases blood clot formation at site of plaque rupture Increased use over last decade as knowledge of benefits spread, prices fell and generics became available 60% decrease in # of heart attacks & sudden cardiac death 17% reduction in stroke Framingham risk score, Heart Protection Study, JUPITER study

5 ACE-Inhibitors Block conversion of angiotensin I to angiotensin II Medication end with pril Indicated for hypertension, MI, CHF Slows disease progression Interferes with ventricular remodeling In several trials of acute MI: Promoted survival, decreased incidence of heart failure Decreased incidence of reinfarction and need for revascularization

6 Side effects: cough, renal insufficiency and angioedema Females at greater risk of angioedema to lower part of face or airway Black females at even great risk

7 Amiodarone Class III Antiarrhythmic approved for use in US in 1985 Used for ventricular and supraventricular arrhythmias including: Unstable Ventricular Tachycardia refractory to other therapy and prophylaxis of Recurring Ventricular Fibrillation Suppress and prevent recurrence of SVTs refractory to conventional treatment, esp. assoc. with Wolff-Parkinson-White syndrome, Paroxysmal Atrial Fibrillation, Atrial Flutter, Ectopic Atrial Tachycardia, Paroxysmal SVT from AV nodal re-entry tachycardia in patients with W-P-W syndrome

8 Prolongs action potential duration and the refractory period in all cardiac tissues Decreases sinus node automaticity and junctional automaticity, prolongs AV conduction and slows automaticity of spontaneously firing fibers in the Purkinje system Refractoriness is prolonged and conduction is slowed in accessory pathway in patients with WPW syndrome

9 Available in IV and PO Mild negative inotropic effect that is more prominent with IV than oral administration Causes coronary and peripheral vasodilation Decreases peripheral vascular resistance (afterload) IV: 300 mg for cardiac arrest 150 mg bolus over 10 min for dysrhythmias followed by infusion at 60 mg/hr x 6 hrs., then 30 mg/hr. x 18 hrs. PO: mg daily or BID

10 Side effects: Pulmonary toxicity Interaction with simvastatin at doses >20 mg can lead to rhabdomolysis which can lead to renal failure Thyroid abnormalities Corneal micro-deposits Abnormal liver enzymes Blue-grey discoloration of skin esp. in lighter skin tones

11 Clopidogrel ( Plavix ) Approved in 1997 Oral antiplatelet agent used to inhibit clots in CAD, PVD and with CVA Platelet inhibit demonstrated 2 hrs. after single oral dose of 75 mg but onset of action slow Dosing indicated for ACS pts. Treated by PCI is a 300 mg loading dose followed by 75 mg/day along with mg of aspirin/day ** Indicated for prevention of vascular ischemic events, NSTEMI, STEMI, for prevention of thrombosis after intracoronary stent Side effects include neutropenia and thrombotic thrombocytopenic purpura (TTP) ** CURRENT-OASIS 7 Trial reduces major cardiovascular events in ACS pts. during and after PCI

12 Glycoprotein IIb/IIIa Inhibitors New class of antithrombotic agents Provide more comprehensive blockade than the combination of heparin and aspirin Work to prevent platelet aggregation and thrombus formation Used during Percutaneous coronary interventions with or without intracoronary stent and for treatment of acute coronary syndromes Have demonstrated reduction in combination of death, MI and urgent coronary revascularization Three parenteral agents currently available: Abciximab (ReoPro) Eptifibatide (Integrilin) Tirofibin (Aggrastat)

13 Abciximab (ReoPro) used in interventional cardiology as bolus plus infusion Pts. Have show a 35-50% reduction in primary end point of death, nonfatal MI, refractory ischemia, or urgent revascularization within 30 days esp. in pts. With unstable angina * Eptifibatide (Integrilin)and Tirofiban (Aggrastat) used in ACS at onset of CP or with ischemic change on ECG or any CK-MB elevation above upper limits of normal Used in combination with low-dose thrombolytics in AMI to achieve reperfusion *EPIC, EPILOG and EPISTENT trials translated to 35-56& reduction in relative risk for endpoint regardless of method of revascularization.

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15 Angiomax (Bivalirudin) Anticoagulant for use in pts. Undergoing PCI, and in pts. With or at risk for HIT/HITTS undergoing PCI Direct thrombin inhibitor Synthetic version of hirudin- naturally occurring drug found in saliva of medicinal leech Onset of action almost immediate after IV bolus Prolongs ACT, PT, aptt that returns to normal within 1-2 hours Horizons AMI and REPLACE-2 trials demonstrated efficacy and reductions in major bleeding versus heparin + GP IIb/IIIa inhibitors

16 Dosing: 0.75 mg/kg loading dose followed by 1.75 mg/kg/hr for up to 4 hrs. then 0.2 mg/kg/hr for up to 20hr. If needed Perform ACT 5 after first bolus and give additional bolus if needed

17 Platelet Inhibitors Inhibit Platelet Activation ASA Clopidogrel (Plavix) Heparin Angiomax Inhibit Platelet Aggregation IIb/IIIa Inhibitors Abciximab (Reopro) Eptifibitide (Intregrillin) Tirofiban (Aggrastat)

18 Vasopressin Antidiuretic hormone, found in humans Secreted from posterior pituitary gland in response to reduction in plasma volume Causes kidneys to conserve water Raises BP by moderate vasoconstriction Doesn t have negative effect on myocardium Used to treat Asystole & Shock Increases responsiveness of catecholamines 40 units IV during resuscitation Infusion units/min or 1-4 units/hr

19 Natrecor ( Nesiritide ) Approved 8/2001 for treatment of pts. With acute decompensated CHF who have SOB at rest or with minimal activity Recombinant form of human B-type natriuretic peptide, a naturally occurring hormone secreted by the ventricles Manufactured from E. coli Produces dose-dependent reduction in PCWP and systemic arterial pressure* *VMAC Trial

20 Side effects occur during first 24 hrs of infusion Hypotension, VT, angina, bradycardia, HA, abdominal/back pain Bolus of 2 mcg/kg followed by a continuous infusion of 0.01 mcg/kg/min for 48 hours don t give in line with other meds Monitor BP often If hypotension occurs, the dose should be discontinued and restarted at a dose that is 30% of prior dose

21 Primacor Phosphodiesterase inhibitor with positive inotrope and vasodilator properties Increases CO without increasing HR or myocardial demand Decreases SVR, preload, and afterload Improvement in Left ventricular function and relief of CHF symptoms in patients with ischemic heart disease observed Used for short-term management of severe CHF including low output states following cardiac surgery 50 mcg/kg IV slowly over 10 minutes then maintenance infusion of mcg/kg/min

22 Side effects: Arrhythmogenic Decreases potassium Thrombocytopenia Headache Tremors Chest pain

23 So, what do the next ten years look like? Emerging discoveries in the field of pharmacogenomics are yielding a personalized era of drug therapy Sensors have been developed on chips that can detect in blood, urine or saliva, protein or gene patterns that fluoresce known patterns assoc. with particular disease states. Some chips search for SNPs ( single-nucleotide polymorphyisms) a DNA sequence variation that occurs between members of a species & have been shown to be a predictive of heart disease.

24 What s already in the pipeline? Cardiac myosin activators Enhance contractility without altering intracellular calcium levels Treat CHF Alpha natriuretic peptide medications Regulate Na+ and fluid homeostasis Decrease PCWP and SVR For acute decompensated HF More stem cells research Computers & imaging techniques Less invasive techniques but more information