But after discovering that without the coca the locals were barely able to work, the conquistadors legalized and taxed the leaf, taking 10% off the value of each crop. In 1569, Spanish botanist Nicolás Monardes described the indigenous peoples practice of chewing a mixture of tobacco and coca leaves to induce "great contentment":

When they wished to make themselves drunk and out of judgment they chewed a mixture of tobacco and coca leaves which make them go as they were out of their wittes. In 1609, Padre Blas Valera wrote:

Coca protects the body from many ailments, and our doctors use it in powdered form to reduce the swelling of wounds, to strengthen broken bones, to expel cold from the body or prevent it from entering, and to cure rotten wounds or sores that are full of maggots. And if it does so much for outward ailments, will not its singular virtue have even greater effect in the entrails of those who eat it? Isolation and naming
Although the stimulant and hunger-suppressant properties of coca had been known for many centuries, the isolation of the cocaine alkaloid was not achieved until 1855. Various European scientists had attempted to isolate cocaine, but none had been successful for two reasons: the knowledge of chemistry required was insufficient at the time, and contemporary conditions of sea-shipping from South America could degrade the cocaine in the plant samples available to European chemists.The cocaine alkaloid was first isolated by the German chemist Friedrich Gaedcke in 1855.
The frontal plane QRS is the most helpful clue to distinguish between an ostium secundum ASD and an ostium primum ASD. In primum defects left axis deviation is seen in most patients with an axis of > -30 degrees and very few patients have right axis deviation. In contrast ostium secundum defects have an axis between 0 degrees and 180 degrees with most cases to the right of 100 degrees.In the ECG above, you can see an example of the rSR pattern in V1 with a R greater than S with T wave inversion which is commonly seen in volume overload right ventricular hypertrophy. Diagnosis
Classification
A defect in the ostium primum is occasionally classified as an atrial septal defect, but it is more commonly classified as an atrioventricular septal defect. Treatment
Hemodynamically significant ASDs (flow ratio 1.5:1) are large enough to be closed surgically. The long term prognosis is excellent. Pulmonary hypertension with shunt reversal is a contraindication for surgery, however the pulmonary hypertension can frequently be treated with medicines. The hole can then be closed safely with a good long term prognosis. References
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