Cardiodepression

Propranolol may increase procainamide plasma levels. Additive cholinergic effects may occur when procainamide is administered with other drugp with anticholinergic effects. There is the potential of additive cardiodepressant effects when procainamide is administered with lidocaine. When a beta blocker, such as Inderal, is administered with lidocaine, there is an increased risk of lidocaine toxicity. 

Uses of antianginal drugs (D). For relief of the acute anginal attack, rapidly absorbed drugs devoid of cardiodepressant activity are preferred. The drug of choice is nitroglycerin (NTG,... 

In multidrug therapy, it is necessary to consider which agents rationally complement each other. A p-blocker (bradycardia, cardiodepression due to sympathetic blockade) can be effectively combined with nifedipine (reflex tachycardia), but obviously not with verapamil (bradycardia, cardiodepression). Monotherapy with ACE inhibitors (p. 124) produces an adequate reduction of blood pressure in 50% of patients the response rate is increased to 90% by combination with a (thiazide) diuretic. When vasodilators such as dihydralazine or minoxidil (p. 118) are given, p-blockers would serve to prevent reflex tachycardia, and diuretics to counteract fluid retention. 

Like chloroquine, quinine binds with plasmodium DNA, thus interfering in the synthesis of nucleic acids and preventing its replication and transcription. Quinine also suppresses a large portion of the enzymatic system and therefore it is characterized as a general protoplasmid toxin. This fact agrees well with the action of quinine on membranes, its local anesthetizing and its cardiodepressive effects. 

In patients with cardiac arrest, for example as a result of an intoxication with local anaesthetics, quinine or other cardiodepressant drugs, the stimulatory action of adrenaline on the impulse formation and propagation in the heart can be life saving. 

Verapamil additive cardiodepressant activity when combined with a -blocker additive impairment of AV conducton when combined with digoxin. Diltiazem as mentioned for verapamil. 

Dihydropyridine-CA have been developed with a certain degree of vascular selectivity, which implies that at therapeutic doses such compounds would have less negative influence on cardiac contractile force or none at all. Indeed, a few of such compounds are devoid of cardiodepressant (negative inotropic) activity. Examples of such compounds are amlodipine, felodipine, isradip-ine, lacidipine, lercanidipine and manidipine. 

This is a class IB drug used primarily for the emergency treatment of ventricular arrhythmias. It has little effect on sinus node automaticity but depresses normal and abnormal forms of automaticity in Purkinje fibres. It is generally ineffective against supraventricular and accessory pathway-induced (e.g. WPW syndrome) arrhythmias. Lidocaine is relatively safe and free from adverse cardiovascular side effects. It causes minimal cardiodepression, although high doses can cause heart block. The most common side effect is a dose-related CNS toxicity. It is given intravenously as a bolus of 1 mg-kg-1 followed by an infusion of 20-50 pg-kg-l-min-1. 

S) Increased risk of renal toxicity Blockade of normal compensation for cardiodepressant effects (S)... 

A number of industrial chemicals have been linked to cardiotoxicity. Aldehydes and primary alcohols that can be metabolically oxidized to aldehydes have exhibited cardiodepressant effects. Acute exposure to ethanol has caused arrhythmia. Isopropyl alcohol (2-propanol), a widely used industrial chemical and personal care product, may cause cardiovascular depression and excessively rapid heartbeat. Some halogenated hydrocarbons, including chloroform, ethyl bromide, and trichlo-rofluoromethane, have been implicated in cardiovascular disorders, including arrhythmia. 

Barry YA, Labow RS, Keon WJ, et al. 1990. Atropine inhibition of the cardiodepressive effect of mono( 2-ethyl hexyl)phthalatc on human myocardium Toxicol Appl Pharmacol 106 48-52. 

Tab. 3.8 Catamphiphilic drugs interaction with dipalmitoyl-phosphatidic acid and cardiodepression. (adapted from ref. 12)...

CALCIUM CHANNEL BLOCKERS ANAESTHETICS - LOCAL Case reports of severe 1 BP when bupivacaine epidural was administered to patients on calcium channel blockers Additive hypotensive effect both bupivacaine and calcium channel blockers are cardiodepressant in addition, epidural anaesthesia causes sympathetic block in the lower limbs, which leads to vasodilatation and 1 BP Monitor BP closely. Preload intravenous fluids prior to the epidural... 

Scholz H. Antiarrhythmischer und Kardiodepressive Wirkungen antiarrhythmischer Substanzen. [Anti-arrhyth-mic and cardiodepressive effects of anti-arrhythmia agents.] Z Kardiol 1988 77(Suppl 5) 113-19. 

Schlepper M. Cardiodepressive effects of antiarrhythmic drugs. Eur Heart J 1989 10(Suppl E) 73-80. 

Herzig S, Ruhnke L, Wulf H. Functional interaction between local anaesthetics and calcium antagonists in gui-neapig myocardium 1. Cardiodepressant effects in isolated organs. Br J Anaesth 1994 73(3) 357-63. 

Gottlieb SS, Weinberg M. Cardiodepressant effects of mexiletine in patients with severe left ventricular dysfunction. Eur Heart J 1992 13(l) 22-7. 

Propofol is a cardiodepressant and resets the baroreflex set-point, with a tendency to bradycardia (which occurs in some 5% of cases), hypotension (16%), or both (1.3%) (8). The hypotension may be brought about by peripheral vasodilatation, reduced myocardial contractility, and inhibition of sympathetic nervous system outflow (9). Four deaths due to cardiovascular collapse during induction have been reported in patients aged 78-92 years given propofol 1.1-1.8 mg/kg (10). The patients were of ASA classes 3 or 4. 

In 28 subjects given either sevoflurane -I- nitrous oxide or enflurane + nitrous oxide anesthesia, sevoflurane caused fewer cardiodepressant effects than enflurane (3). Nevertheless, in 10 healthy subjects atrial contraction and left ventricular diastolic function, including active relaxation, passive compliance, and elastic recoil were impaired by sevoflurane (1 MAC) (4). 

Oostendorp J, Kaumann AJ. Pertussis toxin suppresses carbachol-evoked cardiodepression but does not modify cardiostimulation mediated through P,-and putative P4-adrenoceptors in mouse left atria no evidence for P2- and P3-adrenoreceptor function. Naunyn Schmiedebergs Arch Pharmacol 2000 361 134-145. 

Less M block than quinidine and no alpha block, but more cardiodepressant. 

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