In the 1970s potassium cardioplegia was utilized. Cardioplegia minimized the oxygen demands of the heart, thus the effects of ischemia were also minimized. Refinement of cardioplegia in the 1980s made CABG less risky (lowering perioperative mortality) and thus a more attractive option when dealing with CAD.In the late 1960s, after the work of Rene Favaloro, the operation was still performed in a few centers of excellence, but was anticipated to change the landscape of Coronary Artery Disease, a significant killer in the developed world. More and more centers began performing CABG, resulting in  114,000 procedures/year in the USA by 1979. The introduction of PCI did not lead to the abandonment of CABG; the number of both procedures continued to increase, albeit PCIs grew more rapidly. In the following decades CABG was extensively studied and compared to PCI. The absence of a clear advantage of CABG over PCI led to a small decrease in numbers of CABGs in some countries (like the USA) at the turn of the millennium, but in European countries CABG was increasingly performed (mainly in Germany). Research is still ongoing on CABG vs PCI.In the history of graft selection, again the work of Favaloro was fundamental. He established that the use of bilateral IMAs was superior to vein grafts. The following years, surgeons examined the use of other arterial grafts (splenic, gastroepiploic mesenteric, subscapular and others) but none of these matched the patency rates of IMA.
It might even lead to other complications such as arrhythmias, rupture of the papillary muscles of the heart, or sudden death.Medical community has various modalities to detect CAD and examine its extent. Apart from history and clinical examination, noninvasive methods include Electrocardiography (ECG) (at rest or during exercise) and chest X-ray. Echocardiography can provide useful information on the functioning of myocardium, as the enlargement of Left Ventricle , the Ejection Fraction and the situation of heart valves. The best modalities to accurately detect CAD though are the coronary angiogram and the Coronary CT angiography. Angiogram can provide detailed anatomy of coronary circulation and lesions albeit not perfect. Significance of each lesions is determined by the diameter loss. Diameter loss of 50% translates to a 75% cross-sectional area loss which is considered moderate, by most groups. Severe stenosis is considered when the diameter loss is 2/3 of original diameter or more, that is 90% loss of cross-sectional area loss or more. To determine the severity of stenosis more accurately, interventional cardiologists might also employ Intravascular ultrasound. Intravascular ultrasound utilizes ultrasound technology to determine the severity of stenosis and provide information on the composition of the atheromatic plaque. Fractional flow reserve also can be of use. With FFR, the post-stenotic pressure is compared to mean aortic pressure. If the value is <0,80, then the stenosis is deemed significant. Indications for CABG
Stable patients
People suffering from angina during exercise are usually first treated with  medical therapy.