Looking for the Source
Amazed by the detailed pictures before him, the man asked if the clots could be taken out. They couldn’t, Wang told him; what was done, was done. But it was essential to find out where those clots came from or it could happen again. Blood clots like this usually come from either the heart or the arteries that lead from the heart to the brain and eye. The CT done in the hospital showed his carotid artery. No clots there. They would need to look in the heart. But, Wang added, in up to 40 percent of strokes, the source of the clot is not found.
The most effective way to see the heart in action is with an echocardiogram, Wang told the man. Most of the time, the echo will be normal. Still, if something shows up, it’s often important information.
A second stroke is most likely within a few days of the first. This patient was still inside that window. Wang sent the patient to the emergency room at Yale New Haven Hospital and sent a note to the attending physician on duty. It seemed clear to him that this was indeed a kind of emergency.
Joshua Hyman was a fourth-year medical student just starting an ultrasound elective in the E.R. The attending physician, Dr. Karen Jubanyik, suggested that he see this new patient who was there for an echo. Jubanyik gave the student a quick rundown of the case. Hyman introduced himself to the patient, then asked if it would be OK if he took a look at his heart. It wouldn’t be the official echo, Hyman told the patient, it was just a way for him, a student, to learn.
The patient agreed, and Hyman rolled the bulky machine into the tiny cubicle. He squirted gel onto an ultrasound probe and placed it a couple of inches below the patient’s left clavicle, just past the sternum, in the space between the third and fourth rib. He was still learning this technology, but he loved the way it could give you information about what was going on inside a patient’s body faster and sometimes better than just about anything else. Normally with the probe in this position, you see the light gray muscles of the two chambers on the left side of the heart squeezing around a dark center of black that is the blood — it’s the best way to see the business side of the heart, where blood from the lungs is injected into the bloodstream.
What he saw instead took his breath away. In the middle of the dark pools of moving blood was an enormous bright ball zooming back and forth across the screen with every heartbeat. What was that? Hyman froze the picture and took a measurement. A normal heart is about the size of a fist. This flapping circle was kiwi-size.
