Left anterior descending coronary artery

Figure 4.2 Epicardial ECG recorded from an isolated blood-perfused rat heart at the moment of reperfusion. The heart was made regionally ischaemic by occluding a snare around the left anterior descending coronary artery and, after 10 min, reperfused by releasing the snare. Note the rapid onset of ventricular tachycardia (VT) and its subsequent degeneration into ventricular fibrillation (VF). Reproduced with permission from Lawson (1993).

LC is a 51 -year-old female with a history of CHD (stent placement in the left anterior descending coronary artery 3 years prior) and type 2 diabetes who is referred to you for follow-up of her cholesterol. She is taking simvastatin 20 mg once daily in the evening for her cholesterol, and metformin 2000 mg once daily in the evening and piogliti-zone 15 mg once daily for diabetes. Her diabetes is well controlled. Her laboratory test results are within normal limits, except for her fasting lipid profile total cholesterol 215 mg/dL (5.57 mmol/L), triglycerides 135 mg/dL (1.53 mmol/L), HDL cholesterol 51 mg/dL (1.32 mmol/L), and LDL cholesterol 137 mg/dL (3.55 mmol/L). 

Coronary artery bypass was found to decrease blood plasma TAC (T1). Similarly, a brief episode of myocardial ischemia due to elective coronary angioplasty on the left anterior descending coronary artery decreased TAC of blood plasma in the great cardiac vein after 1 and 5 min of the angioplasty TAC returned to normal after 15 min (B22). Another study found lower TAC in the great cardiac vein than in aorta aortic levels before baloon inflation, and its further decrease after 1 min (R19). 

The first phase I clinical trial of coronary angiogenesis demonstrated the safety of intramyocardial injection of 0.01 mg/kg of FGF-I (79), A total of 40 patients undergoing CABG of the internal mammary artery (IMA) to left anterior descending coronary artery (LAD) were randomized to receive intramyocardial injections of either 0,01 mg FGF-1 or placebo. All the patients had further stenoses of the LAD distal to the anastomosis, Coronary angiography 12 weeks after treatment showed increased capillary refill in patients... 

To measure left ventricular external diameter (LVED), two ultrasonic transducers are fixed to the left ventricular wall. One crystal is sutured to the posterior wall within the rectangular area formed by the left circumflex coronary artery and the left posterior descending artery. The other one is placed near the first diagonal branch of the left anterior descending coronary artery. Exact positioning is assured with an oscilloscope. 

A 34-year-old man developed palpitation, shortness of breath, and chest pain. He had smoked a quarter to a half an ounce of marijuana per week and had taken it 3 hours before the incident. He had ventricular tachycardia at a rate of 200/minute with a right bundle branch block pattern. Electrical cardioversion restored sinus rhythm. Angiography showed a significant reduction in left anterior descending coronary artery flow rate, which was normalized by intra-arterial verapamil 200 micrograms. 

A 22-year-old man with a 6-year history of intravenous heroin use was maintained on methadone 60 mg/day and dihydrocodeine 0.5 g/day. He had an extensive anterior myocardial infarction as a result of occlusion of the left anterior descending coronary artery, which was reopened by percutaneous transluminal coronary angioplasty. 

A 29-year-old woman taking bromocriptine 5 mg/day postpartnm had a dissection of the left anterior descending coronary artery and needed emergency bypass grafting. She made a good recovery. 

A 43-year-old woman with controlled hypertension, but no other known coronary risk factors, had an acute myocardial infarction. She took two oral doses of methysergide 2 mg 12 hours apart, followed by sumatriptan 6 mg subcutaneously. About 10 minutes after the sumatriptan, she complained of chest pain, and on arrival in hospital, an anterior myocardial infarction was diagnosed. Subsequent angiography showed a solitary stenosis in the left anterior descending coronary artery, and it was therefore presumed that she had suffered vasospasm associated with this stenosis. She made an excellent recovery after stenting. 

LM is a 50-year-old man who underwent PCI to revascularize a 100% occluded left anterior descending coronary artery. For the procedure he will receive heparin, abciximab, and aspirin. Baseline platelet count is 150,000/mm. Two hours after the bolus dose of abciximab is given, platelet count is TOOO/mm. What clinical intervention(s) should occur ... 

The myocardium and specific conduction system (SCS) are perfused by the right coronary artery (RCA), the left anterior descending coronary artery (LAD) and the circumflex coronary artery (LCX). Figure 1.1 shows the great correlation of coronary angiography and CMDCT in normal coronary tree and some pathologic cases. 

RCA or the LCX, depending on which of them is dominant (the RCA in >80% of the cases). Segment 15 often receives blood from LAD. (E) Correspondence of ECG leads with the bull s-eye image. Abbreviations LAD, left anterior descending coronary artery SI first septal branch D1 first diagonal branch RCA, right coronary artery PD, posterior descending coronary artery PL, posterolateral branch ... 

Figure 3.21 (A) ECG with a quite negative T wave in V1-V2 to V5, with extension to I and VL corresponding to a critical lesion in the proximal part of left anterior descending coronary artery that practically normalises during a chest pain crisis (B). This corresponds to an atypical pattern of STE-ACS (see Figure 8.3B). The normalisation of this...

Figure 4.10 In an acute coronary syndrome with ST-segment elevation in V1-V2 to V4-V6 as the most striking pattern, the occluded artery is the left anterior descending coronary artery (LAD). The correlation of the ST-segment elevation in V1-V2 to V4-V5 with the ST morphology in II, III and VF allows us to know if it is an occlusion proximal or distal to D1 (see Figure 4.43). If it is proximal, the involved muscular mass in the anterior wall is large and the injury vector is directed not only forward but also upward, even though there can be a certain...

B) Drawing of coronary angiography that shows tight stenosis of the mid-left anterior descending coronary artery. 

Arbane M, Goy JJ. Prediction of the site of total occlusion in the left anterior descending coronary artery using admission electrocardiogram in anterior wall acute myocardial infarction. Am J Cardiol 2000 85 487. 

De Zwan C, Bar H, Wellens HJ. Characteristic ECG pattern indicating a critical stenosis high in left anterior descending coronary artery in patients admitted because of an impend-ing infarction. Am Heart J 1982 103 730. 

Engelen DJ, Gorgels AP, Cheriex EC et al. Value of the electrocardiogram in localizing the occlusion site in the left anterior descending coronary artery in acute anterior myocardial infarction. J Am Coll Cardiol 1999 34 389. 

Fiol M, Cino J, Carrillo A, I et al. The value of an algorithm based on ST segment deviations to locate the place of oc-clussion in left anterior descending coronary artery in case of ST-segment elevation-myocardial infarction 2007. Submitted. 

Ibanez B, Navarro F, Farre J et al. Tako-Tsubo transient left ventricular apical ballooning is associated with a left anterior descending coronary artery with a long course along the apical diaphragmatic surface of the left ventricle. Rev Esp Cardiol 2004 57 209. 

Sapin PM, Musselman DR, Dehmer GJ, Cascio WE. Implications of inferior ST segment elevation accompanying anterior wall myocardial infarction for the angiographic morphology of the left anterior descending coronary artery morphology and site of occlusion. Am J Cardiol 1992 69 860. 

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