Our protocol was designed to increase the delay in recovery from intracellular acidosis to potentiate the cardioprotective effects of the original protocol of postconditioning. No pharmacological agent or special equipment is necessary for this method, so it is very safe and readily available in any catheterization laboratory around the world. Most patients may not be able to reproduce the postconditioning with lactate-enriched blood procedures, or PCLeB, only by reading lab papers.
So visual demonstration can help with implementation. After pinpointing the occluded lesion by coronary angiography, and finishing the wiring procedures, move the balloon catheter forward and place the balloon at the occluded lesion. To determine whether the balloon is appropriately placed at the lesion, deliver a large volume contrast medium into the culprit coronary artery.
After checking the balloon position, the contrast medium will fill the lumen from the manifold to the tip of the guiding catheter. Disconnect the syringe injector from the manifold and connect a thirty milliliter syringe. Then aspirate twenty to thirty milliliters of lactated Ringer's solution through the line connected to the inlet of the manifold until the syringe is filled.
When the syringe has been filled, inflate the balloon catheter for twenty to thirty seconds at low pressure, then deflate the balloon and start the initial ten second reperfusion. At the start of the reperfusion, immediately dispense at least four milliliters of Ringer's solution to push all of the contrast medium from the tip of the guiding catheter to visualize whether the coronary flow has been recovered. If the coronary flow is recovered, replenish the syringe with the same volume of lactated Ringer's solution used for pushing out the contrast medium.
Keeping the balloon at the occlusion, inject the lactated Ringer's solution directly into the culprit coronary artery through the guiding catheter over a period of five to seven seconds. In the middle of the injection, have a secondary operator start the balloon inflation so that the inflation is completed a little before the completion of lactated Ringer's solution injection. During the sixty second ischemia period, reload the syringe with four milliliters of contrast medium, and load the medium into the guiding catheter.
Then reload the syringe with twenty to thirty milliliters of fresh lactated Ringer's solution. At the end of the ischemia period, deflate the balloon and begin the next reperfusion, dispensing all of the pre-filled contrast medium to reconfirm the coronary flow. Then start the lactated Ringer's solution injection into the culprit coronary artery through the guiding catheter four to five seconds before the end of reperfusion, having the secondary operator start the balloon inflation in the middle of the lactated Ringer's solution injection as just demonstrated.
Here is electrocardiography data from a 48 year old man presenting with prolonged chest pain that revealed marked ST segment elevation in precordial leads. This resulted in an anterior ST segment elevation myocardial infarction diagnosis. The patient experienced frequent ventricular fibrillation before reperfusion therapy.
Coronary angiography revealed approximal occlusion of the left anterior descending artery with a thrombalysis in myocardial infarction flow grade I.At this time, the aortic systolic pressure was approximately seventy milliliters of mercury. Reperfusion using PCLeB was started sixty minutes after symptom onset. The aortic systolic pressure increased to approximately seventy-five milliliters of mercury at the end of PCLeB, and to eighty milliliters of mercury after the percutaneous coronary intervention.
Thrombolysis in myocardial infarction flow grade III was achieved after PCLeB, and was still observed after stenting and percutaneous coronary intervention. Electrocardiography recorded upon admission to the intensive care unit revealed complete ST resolution. Resting thallium scintigraphy before discharge revealed a well-preserved myocardial viability.
The most important step is trapping a larger volume of lactated Ringer's solution inside the ischemic myocardium in a less diluted form during each brief repeated ischemical period. Stenting can be safely preformed with no fear of the no-reflow phenomenon in contrast to the generally believed theory, distal embolic may not be responsible for the no-reflow phenomenon.
