<prompt> Which of the following is a K channel opener?RanolazineNicorandilVerapamilLignocaine  <response>: NICORANDIL:- K channel opener NO releaser Given for Angina Drug activates ATP sensitive K channels -- Hyperpolarizing vascular smooth muscle. Nicorandil is believed to exe cardioprotective action by simulating ischaemic preconditioning as a result of activation of mitochondrial K-ATP channels. Ranolazine - Inhibits late phase of sodium current Late I Na improving oxygen supply and demand equation. It has antianginal as well as antiarrhythmic propeies. Verapamil :- calcium channel blocker, slows AV conduction directly and decrease HR, contractility, BP and oxygen demand. Lidocaine : class IB antiarrhythmic drug, shoens phase 3 repolarization and decrease the duration of action 