Humans ; Myocardial Infarction ; complications ; therapy ; Myocardial Reperfusion Injury ; etiology ; therapy

Animals ; Humans ; Ischemic Preconditioning, Myocardial ; methods ; Myocardial Ischemia ; complications ; therapy ; Myocardial Reperfusion ; methods ; Myocardial Reperfusion Injury ; etiology ; prevention & control

OBJECTIVETo investigate the clinical implications of reperfusion arrhythmias during primary percutaneous coronary intervention (PCI) for patients with acute myocardial infarction (AMI).

METHODSData from 228 AMI patients in whom the infarct-related artery (IRA) were successfully recanalized by primary PCI were retrospectively analyzed. The 228 patients were divided into 2 groups: myocardial ischemia-reperfusion injury (MIRI) group (n=119) in whom MIRI events occurred within minutes after successful recanalization of IRA, and non-MIRI group (n=109). The 119 patients in MIRI group were further divided into 3 subgroups: severe bradycardia with hypotension (brady-arrhythmia subgroup), lethal ventricular arrhythmias requiring electrical cardioversion (tachy-arrhythmia subgroup), and IRA antegrade flow less than or equal to TIMI 2 grade without angiographic evidence of abrupt closure (no-reflow subgroup).

RESULTS(1) Clinical and angiographic data: Compared with non-MIRI group, MIRI group was characterized by more inferior infarct location, shorter ischemic duration, more frequently right coronary artery as IRA, more diseased vessels, more often TIMI 0 grade of initial antegrade flow in IRA, less pre-infarction angina, more renal insufficiency, and higher in-hospital mortality (13.4% vs. 4.6%, P=0.021). (2) The peak CK level was remarkably lower in brady-arrhythmia subgroup than that in non-MIRI group (2010 IU/L vs. 2521 IU/L, P=0.039). The peak CK or CK-MB level was notably higher in no-reflow subgroup than in non-MIRI group (4573 IU/L, 338 IU/L, respectively, P=0.000). (3) Left ventricular ejection fraction in no-reflow subgroup was significantly lower than in non-MIRI group (38.7% +/- 8.3% vs. 51.2% +/- 8.1%, P=0.000), left ventricular end-diastolic volume in no-reflow subgroup was greater than that in tachy-arrhythmia subgroup [(135 +/- 32) ml vs. (105 +/- 19) ml, P=0.029].

CONCLUSIONReperfusion arrhythmias may imply the existence of much survived myocardium and do not enhance myocardial damage, while no-reflow increases myocardial injury and induces permanent impairment of cardiac function.

Arrhythmias, Cardiac ; complications ; Cell Survival ; Humans ; Myocardial Infarction ; therapy ; Myocardial Reperfusion ; Myocardial Reperfusion Injury ; etiology ; Myocardium ; enzymology ; Retrospective Studies

OBJECTIVETo study the effects of "half-conditioning", a modified postconditioning process, on myocardial injury induced by severe myocardial ischemia/reperfusion (I/R) in anesthetized dogs.

METHODSMongrel dogs of both sexes were subjected to 40 min ischemia (coronary blood flow reduced by 80% via controlled coronary stenosis). At the end of ischemia, dogs were randomly received one of the following treatments: (1) control, reperfusion for 3 h (n = 7); (2) post-conditioning, three cycles of ischemia 30 s followed by reperfusion for 30 s and then reperfusion for 3 h (n = 7); (3) half-conditioning, coronary blood flow recovered to 50% for 2 min, then 80% for 2 min, thereafter 100% for 3 h (n = 7). Electrocardiogram (ECG), arterial blood pressure and left ventricular pressure were monitored throughout the experiment. Plasma creatine kinase (CK) and lactate dehydrogenase (LDH) activity were measured spectrophotometrically. Myocardial necrosis was defined by TTC-staining.

RESULTSCompared with control animals, arrhythmia incidence, LVEDP at 2 and 3 h reperfusion, CK and LDH were significantly reduced in animals received post-conditioning and half-conditioning treatments, infarct size as a percentage (%) of the area at risk was also significantly reduced by post-conditioning and half-conditioning treatments. No differences were observed in the post-conditioning and half-conditioning groups.

CONCLUSIONHalf-conditioning exerts the same cardioprotective effects on post-ischemic hearts as postconditioning.

Animals ; Disease Models, Animal ; Dogs ; Female ; Ischemic Preconditioning, Myocardial ; Male ; Myocardial Reperfusion Injury ; therapy

Humans ; Ischemia ; metabolism ; pathology ; therapy ; Ischemic Postconditioning ; methods ; Myocardial Reperfusion Injury ; metabolism ; pathology ; therapy

Reperfusion is the most effective treatment for acute myocardial infarction, markedly reducing mortality and morbidity. Reperfusion however induces necrotic and apoptotic damages to cardiomyocytes, that were viable prior to reperfusion, a process called myocardial ischemia/reperfusion injury(MI/RI). Over the past 30 years, hundreds of experimental interventions (both pharmacologic and nonpharmacologic) have been reported to protect the ischemic myocardium in experimental animals; however, with the exception of early reperfusion, none has been translated into clinical practice. The population-based survey assessed men have about twice the total incidence of morbidity and mortality of women, and the sex gap in morbidity tends to diminish after age 45 years. So hormone replacement therapy (HRT) is given to treat the MI/RI, and lots of studies shows that the side effect is greater for estrogen, compared with phyestrogen. In this article, we review the important pathogenesis of myocardial ischemia reperfusion injury, the prevention and limitations of HRT. And we highlight the mechanism of phyestrogens treatment the MI/RI in experiment. The aim is to provide the theoretically new way of develop the safe and effective products for the researchers.
Animals ; Humans ; Myocardial Ischemia ; drug therapy ; Myocardial Reperfusion Injury ; drug therapy ; Phytoestrogens ; administration & dosage ; Plant Extracts ; administration & dosage

Animals ; Codonopsis ; chemistry ; Drugs, Chinese Herbal ; pharmacology ; Myocardial Reperfusion Injury ; drug therapy ; Rats ; Selenium ; pharmacology

"Stunning" represents prolonged contractile depression of any muscular component after alleviation of severe ischemia, as shown in reperfusion following acute myocardial ischemia or ischemic stroke. Clinically, it presents with no or delayed recovery past to thrombolytic therapy but its pathogenic mechanism is not fully uncovered yet. We describe a unique case of a 63-year-old woman, who was undertaken endovascular coiling for the aneurysms, deteriorated several hours later without known cause, and showed delayed clinical improvement over the next 3 days following thrombolysis. Immediate post-thrombolysis magnetic resonance imaging scan showed no apparent abnormality except for high signal intensity within the corresponding hemisphere. Reversible, but delayed nature of "brain stunning" can be explained by these images and it seems to be caused by a certain type of reperfusion injury.
Aneurysm* ; Depression ; Female ; Humans ; Ischemia ; Magnetic Resonance Imaging ; Middle Aged ; Myocardial Ischemia ; Reperfusion ; Reperfusion Injury ; Stroke ; Thrombolytic Therapy

OBJECTIVE: To explore the protective mechanism of electroacupuncture preconditioning on myocardial ischemia-reperfusion injury in rats. METHODS: A total of 88 SPF-grade Wistar male rats were randomized into a normal group, a sham-operation group, a model group and an electroacupuncture (EA) group, 22 rats in each one. The rats in the normal group received normal diet and no intervention was given for 7 d. The rats in the sham-operation and the model group were bound for 20 min, once a day for 7 d. In the EA group, EA, continuous wave, 2 Hz and 1 mA, was applied at "Neiguan" (PC 6), "Zusanli" (ST 36) and "Guanyuan" (CV 4) for 20 min, once a day for 7 d. In the 8th day, the blood was collected by abdominal aortic method 60 min after intraperitoneal injection of 10% urethane anesthesia by 10 mL/kg in the normal group, and then the tissue of heart was collected. In the model group and the EA group, ligating the left anterior descending coronary artery (LAD) was adopted for 20 min and reperfusion was applied for 40 min, then the samples were collected. The rats in the sham-operation group recevied open-chest operation and no other intervention, the samples were collected in 60 min. Nitro Blue Tetrazolium Chloride monohydrate (NBT) stain was used to detected myocardial infarct size and weight, ELISA was used to measured myocardial injury markers and inflammatory factors (LDH、CK、cTnI), and the fluorescent quantitative PCR method was used to determine the expressions of FXR and SHP gene. RESULTS: ①There was no significant difference between the normal group and the sham-operation group in myocardial infarct size and weight (>0.05) .Compared with the normal group, myocardial infarct size and weight were higher in the model group (<0.01). Compared with the model group, myocardial infarct size and weight were lower in the EA group (<0.01). ②There was no significant difference between the normal group and the sham-operation group in serum contents of LDH、CK、cTnI (>0.05). Compared with the normal group, the serum contents of LDH、CK、cTnI were higher in the model group (<0.05). Compared with the model group, the serum contents of LDH、CK、cTnI were lower in the EA group (<0.05). ③The expressions of FXR and SHP gene in the model group were higher than those in the normal group (<0.05). The expressions of FXR and SHP gene in the EA group were lower than those in the model group (<0.05). CONCLUSION Electroacupuncture preconditioning could significantly improve cardiac function of rats with myocardial ischemia-reperfusion, reduce infarct size and inflammatory factors, and down-regulate the expressions of FXR and SHP gene. The protective effect may generate based on regulation of FXR/SHP apoptosis signal pathway.
Animals ; Electroacupuncture ; Humans ; Male ; Myocardial Ischemia ; Myocardial Reperfusion Injury ; therapy ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Rats, Wistar

Animals ; Male ; Medicine, Mongolian Traditional ; Myocardial Ischemia/drug therapy* ; Myocardial Reperfusion Injury ; Myocardium ; NF-kappa B ; Rats ; Rats, Sprague-Dawley