Dr. Prakash Krishnan snaking a catheter through the femoral artery to the site of the occlusion while wearing a ZeroGravity suit and using a Siemens fluoroscope.
Minimally invasive interventions have opened a whole new way to treat a variety of cardiac and vascular conditions that were otherwise risky and required a great deal of traditional surgical work. The change is so drastic that cath labs look and feel different, and are often operated separately, from the rest of interventional cardiology, radiology and vascular surgery departments. There are no scalpels, very little blood, clinicians are wearing lead-lined suits, and the docs are usually looking up at screens rather than down at the patients.
“Roto-rooting is basically what we do here,” said Dr. Prakash Krishnan, a professor of interventional cardiology at Mount Sinai Hospital in New York. This is one of the busiest cath labs in the world, and the angio work done here is a high precision job that relies on less elbow grease and more on experience, dexterity, and patience. We got a tour of the facility and watched a procedure to give us an idea of what it’s like being both a patient and clinician inside a modern high-tech cath lab. We’d like to thank the organizers of our trip, Terumo Interventional Systems, makers of innovative technologies such as their leading hydrophilic Glidewire guidewires and other sheaths and catheters that optimize vascular access and entry site management. Terumo, translated as thermometer from Japanese, is the largest medical device company in Japan, and a major developer of vascular devices.
Patient Sarah
Before heading to the actual cath lab, I met Sarah, a lifetime resident of upper Manhattan. She has peripheral artery disease (PAD) caused by plaque occlusions in her legs. She gets tired easily, gets lower extremities claudication, so she can’t walk far, and has put off going to see a doctor about her symptoms. Sarah is in her seventies, so perhaps she was attributing how she feels to simply getting older. But she did go see the doc eventually and was directed straight to the cardiology team at Mt. Sinai. A few weeks before we met, Sarah had an identical procedure performed on her other leg. She was completely relaxed about going through it again, seemingly without a drop of anxiety or fear in her eyes or voice. She felt better after the initial atherectomy and was promised she’d “start running marathons” once both legs are cleared. The preop nurses asked Sarah a lot of questions about her medical history, what caused her to call her doctor that led to her ending up in the cath lab, checked her vitals, and explained in a good bit of detail what’s going to happen during the procedure. She was then ferried to the cath lab to get worked on.
The next time we saw Sarah about an hour later she was moderately sedated and on the operating table. Unlike most other surgeries, with brain procedures being an obvious exception, patients getting roto-rooted and stented are awake and conscious. They can feel pain and can talk with the surgeon, providing feedback on how much pressure they’re feeling during balloon angioplasty, as an example. Sarah went to sleep toward the end of the procedure, which is certainly not uncommon.
When everything was ready, Sarah had her femoral artery cannulated and a catheter delivered over a guidewire to the site of the occlusion. This is where the actual therapy begins, as a tiny directional atherectomy device is pushed to the blockage and then very gently and slowly pushed into the compressed plaque. Here’s a video of two doctors in training under Dr. Krishnan’s supervision performing atherectomy:
Once the atherectomy was finished, the plaque collected in the nose cone of the device was pushed into a plastic cup to be sent to the pathology lab for inspection. Here’s a motivational photo calling for more exercise and a better diet thanks to what was removed from about two inches of Sarah’s artery:
This was repeated a second time until the entire blockage was cleared. Following the atherectomy, an angioplasty balloon that pushed the remaining plaque to the arterial wall was applied twice to two sections of the artery. This is when Sarah was awake and feeling the most discomfort because the balloon had to be inflated for a few minutes to make sure everything inside the lumen was compacted to let blood flow through freely and prevent any emboli from dislodging and causing a potential embolism. At this point, Dr. Krishnan evaluated the state of Sarah’s cleared artery to see whether a stent was necessary to keep it open and decided that it’s healthy enough to stay open on its own. The rest of the procedure involved removing the catheter, tying some loose ends, and wheeling out Sarah to the recovery room.
During the procedure we had a chance to see some interesting technology in action that helps doctors perform these lifesaving procedures safely and at amazing speed. Mt. Sinai’s cath lab was using Siemens fluoroscopes that provide a live X-ray view of the treatment area. Large screens right above the patient provided a clear picture and lead-embedded Glow ‘N Tell tape from LeMaitre Vascular stuck on Sarah’s leg allowed surgeons to measure how far their tools are moving through the vasculature.
In particular, Dr. Krishnan was really enthused about the ZeroGravity lead suits that allow clinicians to work close to X-ray sources like fluoroscopes without having to wear the suits right over their clothing. All they do wear are belts with a magnet about the size of a half dollar on the front which stick to hanging heavily lead lined ZeroGravity suits right in front of the operating table. The suits have cut outs for the arms and move along with the magnet so that the doc is almost completely protected from the radiation without having to wear an extra twenty pounds of lead all day.
The ZeroGravity system did, though, create a problem at some point during the operation when it got stuck by a plastic cover in the ceiling mounted track, and one of the clinicians had to get a step-stool and climb up to get it freed and back in action. It seemed like all in a day’s work at the Mt. Sinai cath lab, and things were “back on track” in about a minute.
We heard back about Sarah’s condition now that it’s been a few weeks since the procedure, and she’s feeling way better, is much more mobile, and doesn’t feel as tired as before.
Best of luck to Sarah and to everyone else getting their vessels cleared!
Link: Mount Sinai interventional cardiology/cath lab info page..