Vernakalant-ul este un antiartimic din clasa III adica blocante de canale de K. Spre deosebire de celelalte din aceeasi clasa mai blocheaza si unele dintre canalele de Na si niste canale particulare de K (a se tine cont ca numarul canalelor de K bate la vreo 60).
Iata ce ne spune Wiki depsre VWENAKALANT-UL NOSTRU
Vernakalant (INN; codenamed RSD1235, proposed tradenames Kynapid and Brinavess) is an investigational drug under regulatory review for the acute conversion of atrial fibrillation. It was initially developed by Cardiome Pharma, and the intravenous formulation has been bought for further development by Merck in April 2009. In September 2012, Merck terminated its agreements with Cardiom and has consequently returned all rights of the drug back to Cardiom.
On 11 December 2007, the Cardiovascular and Renal Drugs Advisory Committee of the US Food and Drug Administration (FDA) voted to recommend the approval of vernakalant, but in August 2008 the FDA judged that additional information was necessary for approval. The drug was approved in Europe on 1 September 2010.
An oral formulation underwent Phase II clinical trials between 2005 and 2008.
Mechanism of action
Like other class III antiarrhythmics, vernakalant blocks atrial potassium channels, thereby prolonging repolarization. It differs from typical class III agents by blocking a certain type of potassium channel, the cardiac transient outward potassium current, with increased potency as the heart rate increases. This means that it is more effective at high heart rates, while other class III agents tend to lose effectiveness under these circumstances. It also slightly blocks the hERG potassium channel, leading to a prolonged QT interval. This may theoretically increase the risk of ventricular tachycardia, though this does not seem to be clinically relevant.
The drug also blocks atrial sodium channels.
Legatura este aici.
Deci, indicatia este pentru FiA si eficienta este cu atit mai mare cu cit frecventa este mai mare.
Ca ES de avut in vedere prelungirea intervalului QT.
O rapida trecere in revista a sugestiilor prin Google, ne arata ca respectiva molecula n-ar fi chiar atit de minunata ea fiind considerata de unii „prea periculoasa pentru FiA acuta”.
Vernakalant. Too dangerous in atrial fibrillation.
The usual aim of treatment for patients with symptomatic paroxysmal or recent-onset atrial fibrillation, including after cardiac surgery, is to slow the heart rate. Electrical and drug (amiodarone) cardioversion are other options. Vernakalant, an antiarrhythmic drug, has been authorised in the European Union for rapid reduction of recent-onset atrial fibrillation. It is only available in an injectable form. Vernakalant has not been compared in clinical trials with treatments slowing the heart rate, or with electrical cardioversion. The only available comparison with another antiarrhythmic agent is a clinical pharmacology study versus amiodarone, a slow-acting drug, based on the rate of cardioversion at 90 minutes in 240 patients. As expected, given the brief observation period, the rate was significantly higher with vernakalant (51.7% versus 5.2%). During clinical evaluation, 6 deaths occurred in the vernakalant groups versus none in the other groups (placebo or amiodarone). The main adverse effects of vernakalant are cardiac arrhythmias (ventricular arrhythmia, torsades de pointes, bradycardia) and severe hypotension. Altered taste, sneezing, paraesthesia, nausea and pruritus were frequent, and respiratory and neuropsychological effects were also reported. A trial in atrial flutter was interrupted when cases of cardiogenic shock occurred. Interactions are to be expected with drugs that prolong the QT interval, and also with drugs that lower the heart rate or the blood potassium concentration. In practice, it is better to continue to use amiodarone for drug cardioversion and to avoid using vernakalant.
Bonus clasificare antiaritmice.
Dar ce lagatura exista intre noi trei, adica eu, Irinel si Vernakalant-ul…
Intre mine si Irinel, este simplu: magistru, urmas in ale cunoasterii. Vernaklant-ul a intervenit intre noi in urma cu citeva zile. Eu nu stiam nimic despre el si Irinel mi l-a semnalizat. Cu aceasta ocazie l-am descifrat impreuna.