This is Chalak Birzingi. I'm an interventional cardiologist in Carilion Clinic and professor of medicine. I work in the cath lab and this course is meant to be for our CVTs. And I'm joined by my colleague, Ryan, who will introduce himself. Hi, my name is Ryan Zawadsky. I'm a CVT here at Carilion. I'm the preceptor here. I've been here for about 12 years and been working in the cath lab for around 20. So there we go. So we have no really conflicts to disclose. So hemodynamic assessment in the cath lab. The cath lab is very valuable in assessing hemodynamics of patients. Of course, we have a variety of patients that comes to us that becomes very integral. And it has been historically for decades now that is in the central role, whether a patient with a valvular disease or shock patient, heart failure patient, pulmonary hypertension, constrictive pericarditis, a variety of medical condition, cardiac conditions that would require assessment of invasive hemodynamics. ECHO has helped a lot in assessing a lot of these hemodynamics outside of the cath lab and that has decreased the need. But nonetheless, the role of the cath lab in assessment of hemodynamics is very essential in a lot of cases. So here we go over some of the basics of the hemodynamic assessment in the cath lab. And me and Ryan will talk about this together. So I think the first and most important when we have a case of, for example, a right and left heart cath or any hemodynamic assessment that we communicate to each other, I usually come to the cath lab and indicate to the team that I have this case coming down. I'll tell them about my access planning. I'm going to go bacillic. I'm going to go femoral, IJ, femoral. And also whether we use ultrasound, what kind of sheath that I would need and so forth. And usually the cath lab sets up the cath in a way that suits the need and answers the question that we are supposed to answer. So Ryan, I'll let you speak. How do you generally prepare the cath lab, the transducers, the flushing of the lines? I know, and I'm sure for pretty much every cath lab employee out there in the U.S. or across the country, one of the hardest things is when you don't have a clear plan. And that's usually the best part of working with certain physicians is when you have a very clear plan of what size sheath you're using for whether you're going radial or femoral or whatnot. And so we have a pretty general tray that we use that we can pretty much add anything we need to it. And depending on what the physician needs from us and what type of procedure we're doing. So whether that means different sheaths, different wire sizing, interventional products, depending on right hearts, left hearts, structural procedures. Very good. So as we do our right heart cath assessment, usually our aim is to produce accurate measurements and to produce waveforms. Mostly hemodynamics is about the waveforms and certain numbers. So it's important to get accurate waveforms. And usually the transducer is outside and the connection is all through the tubing. It's a fluid filled system. So it's important to get all the air out of the system. And actually, in order to take accurate measurements, you would like to contrast to be out of the system at the same time. So because it dampens the pressure waveform. So you want to have nice selling throughout the system and have a nice pressure waveform and traces before you start recording. And you want to make sure that all the catheters are well flushed with happy nice selling. You rebalance the zero line to make sure that you have patients who are very much overweight, that you have to kind of raise the transducer to get to be at the same level as the heart is. And balance, rebalance the zero line and then positions the catheters where they need to be in order to obtain those pressure waveforms. Of course, when we do the oxygen saturation, we typically when we do a cardiac output or we do a SAT run, you want to make sure that in every place that you kind of discard two or three cc's and then get a nice oxygenated blood, whether you are in the PA position, whether you are in the RV position, in the RA position, in the SVC or IVC. And make sure you label those as you hand it over to the tech in order to get those recordings. So basically, a right heart hemodynamic assessment is pressure waveforms and blood samples to obtain oxygenations and make sure that lines are well flushed and set up. Next slide. So as Ryan mentioned, so part of the procedure is really the vascular access and the setup. And it's important to have a clear communication. We expect the interventional or whoever does the procedure to communicate that to the team. If not, the team may be proactive and ask to see which access you would like. Exactly, do you want me to use ultrasound? Shall we open the ultrasound and put it part of the system and the appropriate sheets and catheters that we need? And what's the aim of the study? It's important that the whole team understands what the aim of the study is so that you can answer those by obtaining the right parameters we need. Next slide, please. So this is a case example. This is taken from our own lab. As you can see on the right hand, we took kind of screenshots of the computer, the monitors. You can see that on the top you have an EKG tracing and at the bottom is the waveforms. So you want to make sure that these waveforms, as we said earlier, the zero line is balanced and you have a nice waveform. For the right atrium, typically you will have an A wave and a V wave. And of course, there is an X and Y descents, may not be that prominent, but you will see that nice. And you can correlate that with the EKG to know what's what. And on the right hand side, typically the monitor will tell you this is the peak systolic and this is the A wave. This is the V wave and this is the mean right atrial pressure waveform. And as you are ready, you ask the technician to record. You make sure you have a nice tracing when you do the recording. And you can tell me if you didn't like the recording or the setup of the scale system. So that goes with that. So this one is a right ventricular pressure waveform. You can see there is a peak systolic pressure, diastolic pressure and end diastolic pressure. You would like to have a consistent pressure waveform, nicely flushed lines and correlated with the EKG. And again, on the right hand side, you see the peak RV systolic pressure followed by the diastolic pressure and the end diastolic pressure. And again, our computer system also calculates a dpdt, which is a very important data, even though we don't use it commonly. But this is very important. It's a rate of contraction, a rate of relaxation when you go the negative dpdt. It's important to time the pressure waveforms with the EKG and have accurate recordings and scale it right. And then record it. As you can see on that, if you look from the right atrium to the right ventricle, you can see that they changed their scale. And that can sometimes be a little confusing to physicians. Sometimes the best thing is to make sure you communicate out to them that, hey, I'm changing my scale. It seems like the systolic is kind of going off the top of the page, because that can definitely throw somebody's eyes off. If you go from 100 scale to 50 scale to 100 scale to 50 scale, it can definitely be a little confusing, especially if you're in a teaching facility, if they're trying to teach new fellows or trying to really focus in on certain numbers. It's good, if you're the monitoring person, to make sure you communicate that to your physician, that, hey, I changed from scale to scale just so that this is all on there, so you can really see the descent and whatnot, or the edp or the mean or whatnot. That's a very key thing to do when you're in the cath lab. Yeah. So this is a PA pressure waveform. You can see it. It has a peak systolic and a diastolic. And as you see, during the respiratory cycle, it can change. And on the right-hand side, the computer will calculate the peak systolic and the diastolic and gives you the mean. Here, it's been a little bit off. I think maybe it's related to needs selected. So this is important to pay attention to those. And, again, it correlates that with the EEKG. And you have to pay attention to your scale. For example, this is recorded on a 100 scale, versus if you are in a 40 scale, those pressure waveforms will be a lot more prominent. And the normal peak systolic pulmonary artery pressure anywhere from 15 to 30. The diastolic pressure would be from 4 to 12. Sometimes you get a little higher than that. There will be some respiratory variation. It all depends on the filling condition of the heart. Next one, please. Again, this is a wedge pressure waveform. And you can see maybe a little bit under overdamped pressure. You don't see clearly the waveform very well. Normal pulmonary capillary wedge pressure is similar to the left atrial pressure, but it's a little bit from a distance, a little bit overdamped. But, again, your mean pressure should stay the same, but you don't see here clearly. But you will have a V wave, an A wave, and a V wave, and both the X and the Y descents that goes along with that. Do you want to say something about the scale here, Ryan? This scale would also be on a 100 scale. This would be a good time to change your scale to 40, just so that you can really see those peaks and valleys on your wedge. Because, like Dr. Brzezinski was saying, sometimes you can get really overwedged. And if you're on a high scale, it's hard to really delineate that. One of the things that I've always thought was really neat about the pulmonary capillary wedge was I don't have to go transeptal to get a true LA pressure because there's no valves. Which is very amazing. Right, exactly. And you put a patient at greater risk, whereas finding out that you could take a catheter and wedge it out into the lung, you get an almost direct correlation to what the left atrium is actually doing. Very good. Next slide. This is the left ventricular pressure weight form. Again, you can see there is a peak systolic pressure, there is a diastolic pressure, and there is an end diastolic pressure. You want to have a nice tracing. You want to have the scale at the right amount where you can see the peak systolic and the diastolic pressures. Again, you will see a number next to those from our computer system that gives us DPDT. This is the rate of contraction. Any number, 1400 to 1800, this is a normal number. When we have a weak muscle, the rate of relaxation will be slower and that kind of becomes a lower number. It's a good number to pay attention to, though we don't report it commonly. Part of it is a lot of filling condition dependent, like many other parameters of diastolic function. The left ventricular pressure tracing, you would like to have a nice tracing. Sometimes you can get an overshoot or underdamp. If you have contrast or if you have air bubble in the system, you want to clear it out so you can have a nice weight form for that. This is a good example of a left ventricular pressure because you can see that there is no ectopy in your EKG, which then could show you that you're underneath a papillary muscle or in some trabeculae. This is a point in time where, as the monitor tech, communication is key because if you start to get some PVCs, those PVCs can turn into a pretty lethal arrhythmia very quickly. You can be going at a very boring rate in your procedure to a very exciting rate. You don't want that excitement. No, that's the wrong type of excitement. That's why we have the role of the monitor tech, that constantly the pressure waveform is not there. You kind of pressure. You want to pressure. Or if there's any damping or damping of the pressure, you kind of alert. Or if you have PVCs or runs, you kind of alert the operator that, hey, pay attention to your catheters. You have a run of VTAC or something like that. Next slide, please. Here, a pullback from the left ventricle to the aorta. You can see the left ventricular pressure on the left-hand side and the pulmonary aortic pressure on the right-hand side. And you have a nice diachronic notch in the aortic pressure. And the LV pressure doesn't have any overshoot. And the computer calculates the gradient for you. But by visual, also you can pay attention. You can pay attention and see if there is any gradient across the pullback suggesting a gradient across the aortic valve. So this one is kind of simultaneous pressures. Simultaneous pressures between the left ventricle and the right atrial pressure. And on the you have condition one and condition two. And when you do the simultaneous pressures, typically when we do a valvular case or constrictive pericarditis, we would like to focus on the diastolic pressures. That's why you decrease the scale to about 40 or even less than that so you can clearly see diastolic pressures. So in the blue line, you see the left ventricular pressure waveform and the diastolic pressure. And in the red is the right atrial pressure. And you can have a nice recording of both pressure tracings. Next slide, please. So again, part of the communication when we do a right and left is I usually the tech asks me, do you really want to do simultaneous pressures? And if you do, it's a little bit different from the technical standpoint where they have two transducers. You want to say something about that, Ryan? Yeah, two transducers obviously is going to be a lot more accurate than just a single transducer where you're pulling back and you're getting noise going across different valves or whatnot. So you're definitely in the line of this constriction versus dilation or in aortic stenosis or mitral stenosis. Two deucers is always going to be vastly more accurate and it will paint a better picture for the patient's overall diagnosis and treatment. And it will be exactly simultaneous. So you take both pressures at the very exact same time because it could be beat-to-beat variation, pressure variation, filling condition variation, PVC, tachycardia, bradycardia. So here you have accurately record both. In this tracing, we have the left ventricular pressure tracing and the right ventricular pressure tracing. And you can focus on the systolic waveform and the diastolic waveform. Of course, we don't see the peak systolic for the left ventricle because it's much higher pressure and we are at a 40 scale. This is particularly important when we do the LV and RV, when we suspect constrictive pericarditis, when the computer actually can calculate for us the systolic area index, basically the area of the systole of the left ventricular waveform and the right ventricular waveform. You look into variation of a respiratory cycle in inspiration versus expiration. And based on those, you can calculate and make an estimate whether there is an inter-ventricular filling dependence. So inter-ventricular dependence for filling conditions. When the ventricle fills, the right ventricle fills, pressure goes higher. On the expense of that, because it's a restricted space, the left ventricle will go down and so forth. So in the center of that is really good tracings of hemodynamics and assessment of that. Next slide, please. So this is the PA and the LV simultaneously recorded. And the computer, you will set it up as two conditions. And on the top, you will see the PA tracing. And it tells you the systolic, the diastolic, and the mean. And then on the bottom is you have this LV systolic and diastolic and end diastolic. So simultaneously recorded, the nice tracing, nice waveform. And you correlate that with the EKG so that you can time the waveforms. Next slide, please. This one is a wedge and left ventricle. This is particularly important when we're dealing with cases of mitral stenosis, when the wedge pressure will be high and the left ventricular diastolic pressure will not be as high. In order to do accurate gradient across the mitral valve, you have to have a catheter in the left atrium and one in the left ventricle. Of course, as we mentioned earlier, it's very invasive, risk of major complications. You could do that by wedging your pulmonary catheter. And that way, when the balloon goes up, then the tip of the transducer in the wedge catheter will be listening to the waveforms that comes from the left atrium. So it will be a little bit delayed, but nonetheless, it's pretty accurate. And in diastole, you measure the gradient between the pulmonary capillary wedge pressure and the LV pressure. And that's how you, depending on the amount of the gradient between the two, you calculate the degree of mitral stenosis. Next slide, please. So this is another case. Simultaneously measured the pulmonary capillary wedge and the LV pressure waveform. Next slide. So in addition to pressure waveforms, also in the cath lab, we obtain oxygen saturations by putting the catheters in the position that we like. We could do the SVC, the RA, the RV, the PA, those. And typically, we use the pulmonary artery oxygen saturation with the LV in order to calculate our cardiac output. In order to calculate the cardiac output, there's a few other things that you have to put into the computer, like? You have to put your hemoglobin in. With our computer, we don't have to just assume a O2 consumption. It will actually calculate for us what it thinks the patient's assumed O2 consumption will be. But basically, putting that in, and then it runs it through the whole formula for fake cardiac output. Or you could use thermodilution, where you'll be injecting a saline or a dye. Typically, we use saline, and the change in the temperature will be felt by the tip of the thermistor at the tip of the catheter. And based on that, you calculate cardiac output. Typically, we do one, two, three, and we average the three. If you have good tracing and good waveforms for that area under the curve, calculation of the cardiac output. So right heart cath or hemodynamics allows us to calculate cardiac output, cardiac index, based on FIC by obtaining oxygenation. Difference, or based on thermodilution by changing the temperature. So just to remind you that the FIC method, that even though the computer gives us the numbers right away as we do the injections, but there's a lot of formula behind. And I kind of put those numbers there because you might see that in the board's exam. Definitely. It's one of those things that I think most of us take for granted, that these computer systems do all these things for us. But there's some very in-depth formulas and equations that go into this calculation. Yeah. Next slide. So we have certain calculated and certain measured. So this is calculated cardiac. We measure some of the parameters and others we calculated based on the ones that we obtained. So like systemic and pulmonary vascular resistance. Next slide, please. So this is just a summary of interpretation of hemodynamic values. We get some directly, like pressure waveforms, some mixed venous oxygenation, and then the others, a variety of indices that we can obtain and help manage the patient. Next slide, please. So this is a case of cardiac tamponade on the left-hand side. You have two pressure waveforms, one in the right atrium, the other one in the intrapericardial space as we open. We gave a lot of fluid to the patient. So that's why the right atrial pressure is high. Patient is hypotensive, hemodynamic collapse. And after we drain the fluid, on the right-hand side, you see the intrapericardial pressure drops. And that way, we save the patient and do a proper filling of the ventricle. Next slide. I think with that, we end our presentation. And we hope that this will be of value to our listeners and the members of our SCI community. Thank you.

hemodynamic assessment

cath lab

clear communication

pressure waveforms

cardiac output

cardiac conditions