Thrombolysis of acute total occlusion of the left main coronary artery in evolving myocardial infarction

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Incidence, predictors, and management of acute coronary occlusion after coronary angioplasty

Acute coronary occlusion occurs in 4.3% to 8.3% of patients during coronary angioplasty. Its occurrence is difficult to predict in an individual patient. At high risk are patients with unstable angina, intracoronary thrombus, extreme age, long complex lesions, and diffuse disease. "Standard" management including redilation (prolonged perfusion) thrombolytic treatment and emergency bypass surgery is only successful in approximately 50% of the patients and is associated with a high mortality and myocardial infarction rate of < 6% and 30%, respectively. Bail-out stent implantation appears to emerge as an effective alternative in suitable patients and might reduce mortality, the apparent progression to myocardial infarction, or might decrease the need for emergency bypass. New techniques including directional atherectomy, rotational ablation, or the excimer laser are associated with a similar frequency of acute occlusion. Immediate access to a surgical back-up facility remains necessary to treat refractory acute occlusions

Maintenance of increased coronary blood flow in excess of demand by nisoldipine administered as an intravenous infusion

Systemic and hemodynamic effects of nisoldipine, administered as a 4.5-micrograms/kg intravenous bolus over 3 minutes followed immediately by an infusion of 0.2 microgram/kg/min over 30 minutes, were studied in 13 patients undergoing diagnostic catheterization for suspected coronary artery disease or follow-up catheterization after coronary angioplasty. Responses to the drug tended to be exaggerated in the first 8 minutes of the infusion, but thereafter produced a steady state, with heart rate increased by 14 +/- 3% at 16 minutes and by 15 +/- 3% at 24 minutes (p less than 0.05), mean aortic pressure decreased 12 +/- 2% and 13 +/- 3% at the same times (p less than 0.05) and coronary venous blood flow increased by 31 +/- 5% and 34 +/- 6% (p less than 0.05). Myocardial oxygen consumption and the heart rate-systolic aortic pressure product were unchanged and cardiac output and stroke volume were significantly increased. Study during matched coronary sinus pacing produced similar trends. Nisoldipine is a potent coronary and peripheral vasodilator that maintains an increase in myocardial oxygen supply in excess of demand when given as an intravenous infusion

Coronary and systemic hemodynamic effects of intravenous nisoldipine

Systemic and coronary hemodynamic effects of the new dihydropyridine calcium antagonist nisoldipine were studied over a 30-minute period in 12 patients with angina pectoris. Previously instituted beta-blocker therapy was continued. Nisoldipine was administered in an intravenous bolus of 6 micrograms/kg over 3 minutes. Heart rate increased as mean aortic pressure and systemic vascular resistance decreased in all patients. Cardiac output increased significantly, from 5.8 +/- 0.3 to 7.9 +/- 0.5 liters/min, 10 minutes after nisoldipine infusion. These trends were maintained over the 30-minute observation period. Coronary sinus blood flow increased from 103 +/- 11 to 139 +/- 13 ml/min immediately after nisoldipine, but had returned to the control level by 30 minutes, as had the reduction in coronary vascular resistance. Myocardial oxygen consumption and heart rate-systolic blood pressure product did not change significantly. Nisoldipine is a potent peripheral and coronary vasodilator free of major myocardial depressant effects after acute intravenous administration. The systemic vasodilatory effects appear to outlast the coronary effects over 30 minutes

Edge detection versus videodensitometry for quantitative angiographic assessment of directional coronary atherectomy

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Chronic pseudoaneurysm of the left ventricle

We present a case of a 55-year-old men who suffered a silent myocardial infarction four years earlier and presented with exertional dyspnoea. Cardiac magnetic resonance imaging (CMR) and Multislice computed tomography (MSCT) was performed and revealed a giant pseudoaneursym of the lateral wall of the left ventricle with the presence of a thrombus in the lateral wall of the pseudoaneursym. We present this case since excellent non-invasive evaluation of the pseudoaneursym was feasible using state-of-the-art imaging modalities. Information on left ventricular geometry and function as well as myocardial viability and coronary anatomy is available when both MSCT and CMR are performed. This combined approach of these two imaging modalities provide clinically relevant information and may guide therapeutic decision making

Reference chart derived from post-stent-implantation intravascular ultrasound predictors of 6-month expected restenosis on quantitative coronary angiography

BACKGROUND: Intravascular ultrasound (IVUS)-guided stent implantation and the availability of a reference chart to predict the expected in-stent restenosis rate based on operator-dependent IVUS parameters ma

Early angiography after myocardial infarction: what have we learned?

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