Active clinical trials for "Myocardial Ischemia"

All preoperative cardiac medications will be continued till the morning of the surgery, except angiotensin converting enzyme inhibitors. Patients will be pre-medicated with intramuscular morphine at 0.1 mg.kg-1 one hour before surgery. Upon arrival to the operating room, Initial monitoring included five lead electrocardiograms, non-invasive blood pressure, and pulse oximetry. At the attending anesthetists discretion, intravenous midazolam (0.05 mg/kg) will be administered for anxiolysis. Under local anesthesia an arterial line will be placed in the right radial artery and central venous line will be placed in the right internal jugular vein. Before induction of anesthesia for all study patients, Electrical cardiometry device (ICON; Cardiotonic, Osypka; Berlin, Germany) will be applied to the patient through 4 electrodes at the following sites: Below the left ear, Above the midpoint of the left clavicle, Left mid-axillary line at level of the xiphoid process and 5 cm inferior to the third electrode. Stroke volume variability (SVV) was measured while patient maintaining standard calm breathing at 8 breath/minute for one-minute. Patients with SVV less than 13% will be excluded from the study. Thus, all patients included will be considered fluid responders[5]. The baseline data in the form of heart rate, systolic, diastolic, and mean systemic arterial pressures, CO, CI, SV, SVI, SVV, SVR, and SVRI will be recorded during the study period in all the patients. Patients will then be randomly divided into two groups; control group will receive nothing before induction, while patients in volume loading group will receive volume loading of 8ml/kg Ringer acetate over 10 minutes. The volume loading will be repeated until SVV would be below 13%. The volume loading would be given by an anesthesia resident not involved in data collection. For induction, Patients in both groups will receive 3 mcg/kg of fentanyl. Then in all patients, propofol will be injected slowly at 1.5 mg/kg in 0.25 mg/kg increments every 20 s till clinical loss of consciousness. Clinical loss of consciousness (defined as no response to auditory command) will be assessed by asking the patients repeatedly every 20 s to open their eyes. After loss of consciousness, atracurium 0.5 mg/kg will be administered to facilitate tracheal intubation. The stress response to laryngoscopy and tracheal intubation is secondary to marked increase in sympathetic activity and manifested in general as tachycardia and hypertension and will be managed with increments 0..25mcg fentanyl. Hemodynamic changes; 20 beats/ minute or 20 mmHg difference in heart rate and blood pressure respectively were considered to be significant. Anesthesia will be maintained by isoflurane (1-1.2 %). Patients will be mechanically ventilated to have target of PO2 above 300mmhg and PCO2 between 35-40mmg. Any episode of hypotension (defined as mean arterial pressure [MAP] < 80% of the baseline reading and/or MAP <60 mmHg) will be managed by 5 mcg norepinephrine (which could be repeated if hypotension persists for 2 minutes). If bradycardia occurred (defined as heart rate less than 50 bpm), it will be managed by IV atropine bolus (0.5 mg). Hemodynamic data will be recorded 1-minte before the induction, 1-and 2-minutes after loss of consciousness, 1-minutes after intubation, then every 2-minutes for 15-minutes after intubation., the end point of the present study. Throughout this period the lungs will be mechanically ventilated with 50% air-oxygen mixture, to maintain an end-tidal carbon dioxide between 35 and 40 mmHg.

The primary purpose of this multi-center study is to collect and study the acoustic and electrical signals created by the heart during the cardiac cycle as a result of stenosis or plaque associated with coronary artery disease (CAD).

CFR has been studied for few years using 82 Rubidium PET (positron emission tomography) /CT. CFR has shown to be correlated with cardiovascular events occurring in the 10 following years. CFR also helps to identify multivessel coronary disease. Few studies have shown the possibility to calculate CFR during myocardial perfusion SPECT on new ultrafast CZT cameras.

The overall question the investigators would like to help answer is whether SE with or without MCE data can be widely used as a first line investigation in women with no previous history of Coronary Artery Disease (CAD) who present with chest pain of recent onset. In order to answer this question the investigators will look at the following: i) Is SE superior to ExECG in terms of cost to diagnosis and negative predictive value of CAD? ii) What is the additive value of myocardial perfusion data to wall motion data for predicting significant CAD on angiography and future cardiac events in women? iii) What is the additive value of Carotid ultrasonography in a large population of women referred for stress testing?

The hypothesis of the study is that aerobic conditioning following acute heart attack will improve autonomic function and electrical stability of the heart.

The objective of this study is to determine the rate of radial artery occlusion and vascular access site complications following transradial angiogram using a new Terumo (Tokyo, Japan) Glidesheath Slender, in comparison with the currently used 6 French (6 Fr.) radial sheath.

The Impact of Compound danshen dropping pill for coronary heart disease (CHD) heart and artery structure and function in patients with hypertension

The new cadmium-zinc-telluride (CZT) technology is a powerful tool for cardiac nuclear medicine. The increased photon counting sensitivity of camera can be used to explore novel protocols like dual isotope (rapid stress Tl-201/rest Tc-99m protocol for use with high-speed SPECT MPI). The use of dual isotope imaging is very interesting because this imaging combines the use of thallium-201 with technetium-99m agents permitting optimal image resolution and simultaneous assessment of viability, all with an exam duration of approximately 20 minutes. However, no study compares stress thallium-201/rest technetium-99m sequential dual isotope high-speed myocardial perfusion imaging versus invasive coronary angiography. The investigators report here the first validation of high-speed protocol with dual isotope for myocardial perfusion imaging using invasive coronary angiography as the standard of reference.

Antiplatelet treatment is important for coronary artery disease(CAD) patients .Some patients are resistant to antiplatelet treatment based on platelet function tests(PFT).Currently the results of PFT are mainly based on the analysis of peripheral blood. instead, adverse cardiovascular events in CAD patients may be more directly related to platelet activities in the coronary arteries. There's no evidence of system study to prove the PFT of peripheral blood can represent the platelet functions in coronary arteries.The purpose of this study is to determine the different platelet activities in the blood of peripheral vein (PV), peripheral artery (PA), intracoronary artery (IC) in the CAD patients without or with different interventions. our study is divided into three parts: Part A: To study the different platelet activities in the blood of PV, PA, IC in the CAD patients with dual antiplatelet therapy. Part B: To explore the different platelet activities of the above three sites in ST-segment elevation myocardial infarction (STEMI) patients who are administrated platelet membrane glycoprotein Ⅱb/Ⅲa (GPⅡb/Ⅲa) receptor antagonist ( tirofiban ) in PV or IC and dual antiplatelet therapy. Part C: To explore the different platelet activities of the above three sites in STEMI patients who are administrated antiplatelet thrombolysin or placebo in PV and dual antiplatelet therapy.

Clopidogrel is essential for the prevention of vascular events in patients after percutaneous coronary interventions (PCI). Most of our current knowledge with clopidogrel originates from the clinical investigations that had used Plavix®/Iscover® from Sanofi-Aventis as the original formulation of clopidogrel-bisulphate. However, as the patency of Plavix® has expired in November 2009 in Hungary, several generic clopidogrel have been introduced to the market. Some of the generics are using the original bisulphate formulation, while others are with besylate salt of clopidogrel. Despite the differences in the clopidogrel-salts, the different carriers might also modulate the pharmacokinetic/pharmacodynamic profile of each drug. As the consequences of the impaired antiplatelet potency might be devastating, including stent thrombosis, the investigators sought to compare generic clopidogrel to the original blister by different assays of platelet aggregation.