Lily-of-the-valley

(Convallaria majalis)

Cardiac Function

Lily-of-the-valley herb consists of the dried, above-ground parts of Convallaria majalis L. [Fam. Liliaceae], or closely related species, as well as their preparations in effective dosage. Lily-of-the-valley is recommended for mild cardiac insufficiency, heart insufficiency due to old age, and chronic cor pulmonale, by the German E commision. (1) The primary indication for Convallaria is cardiac debility, when there is evidence of obstruction and congestion, palpitation, arrhythmia, feeble pulse, dyspnea, diminished renal excretion, venous stasis and generalized edema. Convallaria is considered to be positive inotropic on the myocardium, to lower elevated left-ventricular diastolic pressure, as well as to lower pathologically elevated venous pressure.

It is natriuretic and kaliuretic (1). It believed to be safer than digitalis and freer from cumulative effects. (2)

Pharmacology

Convallaria contains a variety of important glycosides, notably the cardioactive convallatoxin. Several other minor glycosides called cardenolides are also present however, such as cheirotoxin, convallarin, convallamarin, convallamarogenin, and convalloside. A variety of saponin glycosides and flavonoid glycosides can also found in the herb, including quercitin and rutin, as well as a volatile oil. Although convallatoxin has marked cardiac properties, the variety of other constituents found in the whole herb appear to modulate its effects. Convallatoxin was found to interact with membrane phospholipids and promote the binding of calcium ions (3). The effect of dietary cardiac glycosides upon blood pressure regulation was investigated in animals fed a synthetic diet. The administration of convallatoxin in the drinking water was shown to delay the onset of the increase in blood pressure observed in the controls. (4).

To Summarize the actions of cardiac glycosides on the heart are:

1. positive inotropic (increasing contractile strength and velocity while delaying relaxation);
2. negative chronotropic (decreasing the time or rate of contraction);
3. negative dromotropic (decreasing stimulus conduction);
4. positive bathmotropic (increasing stimulation of the ventricular muscle).

Contraindications

Therapy with digitalis glycosides and potassium deficiency.

Increased effectiveness and also side effects of simultaneously administered quinidine, calcium, saluretics, laxatives, and extended therapy with glucocorticoids.

References - Lily of the Valley