Effect of Long-term Application of Crataegus oxyacantha on Ischemia and Reperfusion Induced Arrhythmias in Rats

Abstract

The effect of long-term application of Crataegus oxyacantha on ischemia and reperfusion induced arrhythmias was investigated in Wistar rats on the heart in situ and on Langendorff preparations. Seventeen rats were fed for 8 weeks with 0.5 g/kg b.w. Crataegus extract per day, standardised to 2.2% flavonoids. Twenty age-matched untreated rats served as controls. In the hearts in situ as well as in the Langendorff preparations the left anterior descending coronary artery (LAD) was ligated for 20 min and subsequently reperfused for 30 min. ECG was continuously recorded and the time spent between start of ischemia and onset of arrhythmias was measured. In addition, during ischemia and reperfusion the number of ventricular premature beats and bigemini and the duration of salvos and ventricular flutter and fibrillation were determined. The ischemic area was evaluated in all experiments and coronary flow was measured in Langendorff preparations. In the present experiments, no cardioprotective effects of Crataegus oxyacantha could be detected, neither in the heart in situ nor in the Langendorff preparations. Although the ischemic areas were identical, arrhythmias occurred even earlier in the Crataegus collectives than in the controls. Also the number and duration of ischemia and reperfusion induced arrhythmias tended to occur longer and more frequently in the Crataegus collectives, whilst coronary flow remained unchanged. The phenomenon that Crataegus rather aggravates than prevents arrhythmias may be reduced to a Crataegus induced increase in intracellular Ca(2+)-concentration proven true for the positive inotropic effects of Crataegus.

Application of Traditional Chinese Medicine in Treatment of Atrial Fibrillation

“…Next, the multichannels and multifunctions increase the therapeutic management of AF but reduce the side effects and the amount of drugs that only target one principle. Moreover, since exercise capacity [ 23 ], physical rehabilitation [ 67 ], and some mental problems [ 77 ] can be improved by TCMs, especially the nondrug methods, patients' life quality can be markedly enhanced. Finally, as AF is age-related and the old person has low tolerance for drugs because of declined function of liver and kidney, TCMs which have low adverse reaction [ 43 , 53 ] will be a better choice for them.…”

“…Based on this theory, a research discovered that two proanthocyanidins of its flower heads, catechin and epicatechin, inhibited the biosynthesis of thromboxane A2, leading to antiplatelet effect, but may increase the risk of bleeding [ 12 ]. Currently, hawthorn is widely used in cardiovascular diseases, especially arrhythmia [ 22 ], congestive heart failure [ 23 – 26 ], and hypertension [ 27 ]. Studies demonstrated that the biochemical mechanism of antiventricular arrhythmia is prolonging the APD through blocking the delayed (IK) and inward (IK1) rectifier potassium currents [ 22 ].…”

A review on plants and herbal components with antiarrhythmic activities and their interaction with current cardiac drugs

“… 19 According to electrophysiological studies done by Muller et al., the methanolic extract of Crataegus suppressed both the delayed and inward K+ rectifier currents in guinea-pig ventricular myocytes respectively by 25% and 15% but did not affect ICa-L. 20 Conversely, in another study, the pretreatment of rats with 1% Crataegus oxyacantha extract (8 weeks) had no anti-arrhythmic property during ischemia or reperfusion periods, neither in the isolated nor in situ hearts. 21 Furthermore, in a study on healthy volunteers, an orally single dose of 160 mg Crataegus oxyacantha made no changes in ECG parameters. 22 Some studies reported that Hawthorn can increase the activity of digitalis and hence its potential toxicity and pro-arrhythmic effect and it has been recommended precautions about using this plant with digitalis.…”