Left coronary artery

In a third study the time course of the effects of intravenous and intracoronary injections of cysteinyl leukotrienes on metabolic parameters and systemic and coronary hemodynamics was examined in patients with normal coronary arteries [32]. LTD4 (3 nmol, injected into the left coronary artery) induced an early (20 s), transient fall in mean arterial pressure paralleled by rises in heart rate and plasma levels of epinephrine and norepinephrine, all of which had returned to baseline by 10 min. CVR rose at 10 and 15 min and myocardial oxygen extraction at 15 min. Thus, small doses of cysteinyl leukotrienes may induce both an early, transient fall in mean arterial pressure, with secondary sympathoadrenergic activation, and a later increase in small coronary arteriolar resistance. 

Orotic acid or 6-methyluracil vide infra), when administered to rabbits with myocardial infarction induced by ligation of the anterior descending branch of the left coronary artery, can decrease the incidence of necrosis and increase the rate of regeneration for healthy cellular and fibrous connective tissue in the infarct region [182]. Rats with induced aortal stenosis which are treated with... 

If the gradient is indeed confirmed, a 6 or 7Fr sheath is placed in the left coronary artery from the contralateral femoral artery, in order to reliably assess the ascending aortic pressure even in the presence of intracoronary wires and a balloon inside it (Fig. 2),... 

I/R = ischemia/reperfusion CA = coronary artery LV = left ventricle MI = myocardial infarction and LAD = left anterior descending branch of left coronary artery. 

Femoral blood flow and coronary flow are measured with electromagnetic flow probes attached to the femoral artery and the circumflex branch of the left coronary artery (LCX), respectively. 

An 18-year-old man experienced sudden and severe chest pain while drinking alcohol. He vomited, collapsed, and died. On postmortem examination, thrombosis of the left coronary artery, dilated cardiomyopathy with congestive heart failure, and pulmonary embolism were noted. Blood analysis showed raised cocaine and marijuana concentrations and a trace of alcohol. 

Intracoronary adenosine has been compared with intravenous adenosine for the measure of fractional flow reserve in 52 patients with coronary artery lesions (44). The intravenous dose was 140 micrograms/kg/minute and the intracoronary bolus dose was 15-20 micrograms to the right coronary artery and 18-24 micrograms to the left coronary artery. The two routes of administration were equally effective in measuring hyperemic flow, and adverse effects were limited to two patients who received intravenous adenosine one patient had severe nausea and one patient with asthma had an episode of bronchospasm. 

Isolate an anterior branch of the left coronary artery with a smooth needle on a 3-0 suture for control of flow with PE 50 tubing to form an occlusive snare with the suture. 

Circumflex branch Anterior interventricu ranch of left coronary artery Left... 

The cardioprotective effect of melatonin is demonstrated in several studies in in vivo and ex vivo experimental rat models or cardiomyocytes, as reviewed by Reiter.30 Melatonin administration in perfused rat hearts subjected to ischemia and reperfusion increased postischemic recovery of function, reduced the duration of ventricular tachycardia and ventricular fibrillation and this was associated with decreased lipid peroxidation products and OH radical formation, indicating an antioxidant effect of melatonin.31 Furthermore, in pinealectomized rats, occlusion of the left coronary artery followed by reperfusion resulted in significant increase in infarct size than in intact animals.32 Melatonin acts as scavenger of oxygen or nitrogen based reactants, stimulates antioxidant enzymes, stabilizes cellular membrane, increases the efficiency of oxidative phosphorylation, reduces leukocyte recruitment and adhesion molecule expression and reduces homocysteine induced damage (reviewed by Duncker33). 

Figure 8.43 (A) A 3-year-old girl with abnormal origin of left coronary artery from pulmonary artery. ECG recording previous to a surgical intervention shows very abnormal Q wave especially in VL and V6. Ligature of left coronary...

M9. Meijne, N. G., Bulterijs, A. B., Schoemaker, G., and Eloff, S. J. P., Treatment of dogs with oxygen under high pressure after ligation of the descending branch of the left coronary artery. Diseases Chest 44, 234-250 (1963). 

A model to assess interventions to improve collateral blood flow continuous administration of agents into the left coronary artery in dogs. Cardiovasc Res 1993 27 785-791. 

Dogs weighing 20-30 kg were given 1 ml Combi-len i.m. 60 min before intravenous thiopental anaesthesia (5-lOmg/kg). After 1 mg succinyl cho-Une/kg intravenously the animals were intubated for nitrous oxide narcosis (NjO 02 =3 1). The anterior descending and circumflex branches of the left coronary artery were exposed and an Ameroid constrictor (Litvak et al. 1957) with 2.5 mm diameter was set. Epicardiectomy, cardio-pneumopexy, and omentopexy were performed to induce collateral circulation (for details of operation techniques see Wernitsch 1970). 

The undamaged myocardium contains dehydrogenase and substrate which are capable of reducing the faintly yellowish tetrazolium salt nitroblue tet-razolium (formula [18]) to dark blue formazan. Sandritter and Jestadt (1957) and Jestadt and Sandritter (1959) used 2,3,5-triphenyltetrazolium chloride (formula [17]) in human material and rabbits after ligation of the Ramus descendens of the left coronary artery for microscopic identification of fi esh myocardial infarction, while Nachlas and Shnitka (1963), Andersen and Hansen (1973) and Nitz etal. (1982) utiUsed nitroblue tetrazolium. 3-(4,5-Dimethylthiazolyl-2)-2,5-diphenyltetra-zoUum bromide also gives a blue formazan (Jestadt and Sandritter 1959). 

Fig. 348. Disrupted tunica elastica interna of the ramus circumflexus of the left coronary artery of a dog (No.91) sacrificed 180 days after setting Ameroid constrictors (2.5 mm central lumen) and cardioomentopexy. Formalin. Paraffin section, unstained, embedded in glycerol. Interference contrast FI 50/0.85/ OO/0.17. Agfachrome 50 L professional...

Gregg, D. E. and Shipley, R. E., Changes in right and left coronary artery inflow with cardiac nerve stimulation. Am. J. Physiol. 141, 382 (1944). 

Flg.22.4a-c> A 69-year-old male patient with suspected CAD. MPI showed a reversible perfusion defect in the anterolateral wall. The defect was allocated to a significant stenosis located at the bifurcation of the left coronary artery in ICA. MDCT angiography showed a mixed plaque at the same location, also identified as the culprit lesion. The lesion was rated as a truepositive result for the combination of MDCT angiography and MPI. a Axial reconstruction of MDCT angiography showing a mixed plaque reaching from the bifurcation of the LM into... 

Anterior V2,V3,V, Left coronary artery, left anterior descending (LAO) ll.lll.aVp... 

Lateral 1, aVp, V5, Vg Circumflex branch of left coronary artery II, lll,aVp... 

There are two coronary arteries the right coronary artery which supplies blood to the inferior (bottom) part of the heart and the left coronary artery, which branches off into two further arteries, known as the left anterior descending artery, which supplies blood to the anterior (front) portion of the heart and the circumflex artery which supplies the lateral (side) of the heart. 

Congestive heart failure (CHF) due to ischemic heart disease is a very common clinical situation, particularly in the elderly group of patients. It is however unclear how the myocardial cells behave metabolically when decreased blood flow in the myocardial tissue develops as a result of stenosis, or obstruction of coronary vessels, eventually leading to myocardial infarction. Myocardial metabolism was studied by microcalorimetry and oxygen consumption measurement in tissue from rats with CHF after a myocardial infarction, induced by ligation of the left coronary artery [89]. 

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