Cardiotonic drug

The narrow therapeutic range of digitalis related cardiotonic agents has resulted in an extensive effort to identify compounds in other structural classes which will improve cardiac function. The discovery of the heterocyclic cardiotonic drug, amrinone, led to research on other heterocyclic compounds for that indication. The imidazopyridine, isomazole (57), is representa-... 

Discuss ways to promote an optimal response to therapy, how to manage common adverse reactions, and important points to keep in mind when administering a cardiotonic drug. 

Cardiotonic drugs increase the force of the contraction of the muscle (myocardium) of the heart. This is called a positive inotropic action. When the force of contraction of the myocardium is increased, the amount of blood leaving the left ventricle at the time of each contraction is increased. When the amount of blood leaving the left ventricle is increased, cardiac output (the amount of blood leaving the left ventricle with each contraction) is increased. 

When a cardiotonic drug is administered, die positive inotropic action increases the force of die contraction, resulting in an increased cardiac output. When cardiac output is increased, the blood supply to die kidneys and otiier vital organs is increased. Water, electrolytes, and waste products are removed in adequate amounts, and tiie symptoms of inadequate heart action or HF are relieved, hi most instances, the heart rate also decreases. This occurs because vital organs are now receiving an adequate blood supply because of the increased force of myocardial contraction. 

Diuretics (see Chap. 46) may be ordered for some patients receiving a cardiotonic drug. Diuretics, as well as odier conditions or factors, such as gastrointestinal suction, diarrhea, and old age, may produce low serum potassium levels (hypokalemia). The primary care provider may order a potassium salt to be given orally or IV. 

Intracardial directly into the 0.2-1 5 in., 22 gauge Cardiotonic drugs, calcium... 

Cardiotonic agents are sometimes called positive inotropic drags, i.e. substances that enhance the strength of muscle contractions, and in this case those that enhance the strength of myocardium contraction. Cardiotonic drugs are intended for treating cardiac insufficiency. 

Amin DK, Shah PK, Hulse S, Shellock FG, Swan HJ. Myocardial metaboUc and hemodynamic effects of intravenous MDL-17,043, a new cardiotonic drug, in patients with chronic severe heart failure. Am Heart J 1984 108(5) 1285-92. 

Naphthyridines 460 containing substituted pyridones at position 6 are used as components of cardiotonic drugs (1990USP4866074). 

Indolin-2-on-5-yl)-l,3,4-selenadiazin-2-ones (213) have been tested as cardiotonic drugs they are prepared by the cyclocondensation of indolinones (212) with selenosemicarbazide (Equation... 

The nurse weighs patients receiving a cardiotonic drug daily or as ordered The intake and output are measured, esi ecially if tlie patient has edema or HF or is also receiving a diuretic. Throughout theraj y, the nurse assesses tlie patient for iDeripheral edema and auscultates die lun for rales/crackles throughout therapy. Serum electrolyte levels should be obtained periodically. Hyix)kalemia, hyiiomagnesemia, or hypercalcemia may increase die risk for toxicity. Any electrolyte imbalance is reported to die primary care provider. 

Avoid antacids and nonprescription cou i, cold, allergy antidiarrheal, and diet (weight-reducing) dni unless dieir use has been approved by die primary care provider. Some of diese dni interfere widi die action of die cardiotonic drug or cause odier, ix teiitially serious, problems. (See hiteractions. )... 

Cardiotonic Drugs A Clinical Review, Second Edition, Revised and Expanded, edited by Carl V. Leler... 

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