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Archive for the ‘Cardiology’ Category

Pharm Friday – Antiplatelet Agents Overview

Posted by medliorator on November 13, 2009

Another home run from our friends at Pharmamotion:

Classification:

antiplatelet_agents_classification

  • ADP Antagonists: thienopyridines act by inhibiting the ADP-dependent pathway of platelet activation. These drugs have no direct effect on prostaglandin metabolism.
    • Ticlopidine …is approved for secondary prevention of thrombotic strokes in patients intolerant of aspirin and for prevention of stent thrombosis in combination with aspirin.  adverse effects [include] neutropenia, thrombocytopenia and thrombotic thrombocytopenic purpura.
    • Clopidogrel is approved for prevention of atherosclerotic events following recent myocardial infarction, stroke or established peripheral arterial disease. It is also approved for use in acute coronary syndromes that are treated with either PCI  or coronary artery bypass grafting. It has a better safety profile than ticlopidine.
  • Aspirin: aspirin inhibits platelet cyclooxygenase, a key enzyme in thromboxane A2 (TXA2) generation. Thromboxane A2 triggers reactions that lead to platelet activation and aggregation, aspirin acts as a potent antiplatelet agent by inhibiting generation of this mediator. These effects last for the life of the anucleate platelet, approximately 7 to 10 days… indicated as prophylaxis against transient ischemic attacks, myocardial infarction and thromboembolic disorders. It is also used for the treatment of acute coronary syndromes
  • Phosphodiesterase inhibitors: Dipyridamole acts as vasodilator and antiplatelet agent. It inhibits adenosine uptake and cyclic GMP phosphodiesterase activity, this decreases platelet aggregability  …it is currently used in combination with aspirin or warfarin in the prophylaxis of thromboembolic disorders.  It is also used in stress testing for myocardial perfusion imaging.
  • GPIIb/IIIa inhibitors: used parenterally in patients with acute coronary syndromes…  the integrin GPIIb/IIIa antagonists prevent cross-linking of platelets… current indications include unstable angina that does not respond to conventional therapy in patients that undergo percutaneous coronary intervention.

Antiplatelet agents: mechanisms of action and general overview [Pharmamotion]

Posted in Cardiology, Pharmacology | 2 Comments »

SYNTAX Trial: PCI vs CABG for Severe CAD

Posted by medliorator on September 16, 2009

dph_taxexp_01_cl_us_large

Rationale: Several trials comparing PCI involving bare-metal stents with CABG in patients with multivessel disease [ARTS I Trial, MASS II Trial, ERACI-II Trial & AWESOME Trial] showed similar survival rates but higher revascularization rates among patients with bare-metal stents at 5 years. Others have shown a significant long-term survival advantage with surgery [SOS Trial]. Studies comparing PCI involving drug-eluting stents with CABG have generally been smaller and nonrandomized.

Funding: Boston Scientific (manufacturer of TAXUS Express Coronary Stent System). The sponsor’s biostatisticians performed the analyses; however, data analyses were verified independently by a statistician on a “data and safety monitoring committee”

Endpoints: major adverse cardiac and cerebrovascular events (i.e., death from any cause, stroke, myocardial infarction, or repeat revascularization) throughout the 12-month period after randomization

Methods: 1800 patients with three-vessel or left main coronary artery disease were randomized to undergo CABG or PCI.

Results: Rates of adverse cardiac/cerebrovascular events at 12 months were significantly higher in the PCI group (17.8%, vs. 12.4% for CABG; P = 0.002), in large part because of an increased rate of repeat revascularization (13.5% vs. 5.9%, P<0.001). At 12 months, the rates of death and myocardial infarction were similar between the two groups; stroke was significantly more likely to occur with CABG (2.2%, vs. 0.6% with PCI; P = 0.003).

Percutaneous Coronary Intervention versus Coronary-Artery Bypass Grafting for Severe Coronary Artery Disease [N Engl J Med. 2009 Mar 5;360(10):961-72]

Posted in Cardiology | Comments Off on SYNTAX Trial: PCI vs CABG for Severe CAD

Heart Sounds & Cardiac Exam Primer

Posted by medliorator on October 29, 2008

Blaufuss Medical Multimedia Laboratories offer a free interactive tutorial worthy of a closer look.

  • Cardiac Exam Module
    • heart sounds tutorial
    • quiz
    • detailed animation of S2 splitting.
  • Electrocardiogram Module
    • Supraventricular tachycardia tutorial
    • Interactive ECG viewer
    • interpretations & detailed explanations.

http://blaufuss.org/

Posted in Cardiology, Physiology, Study Tips, Tools | Comments Off on Heart Sounds & Cardiac Exam Primer

News: Patching Heart Holes without Surgery

Posted by wupz on May 10, 2007

Method for patching ventricular defects may help postpone or obviate surgery.

The patch successfully closed ventricular septal defects (VSDs)–or ruptures in the wall between the right and left ventricles–in nearly all patients, allowing blood to circulate normally again and relieving fluid back-up in the lungs. After recovery, patients were able to return to active lives.

 

Before implantation, the flexible double-disc patch is pulled into a catheter, collapsing and compressing it lengthwise. It is then threaded through a vein into the right ventricle and across the rupture into the left ventricle. The patch is pushed partially out of its catheter sheath until the first disc pops open. The catheter is then withdrawn back into the right ventricle, with the first disc positioned against the left ventricular wall and the connecting shaft filling the hole created by the rupture. From inside the right ventricle, the patch is pushed forward again, releasing the second disc, which covers the rupture on the right side of the heart.

Novel Catheter Technique Successfully Patches Holes In The Heart [ScienceDaily]

Posted in Cardiology, News | Comments Off on News: Patching Heart Holes without Surgery