Hemodynamics, Protected PCI
Factoring Hemodynamics into Decisions for Use of MCS During High-Risk PCI
Babar Basir, MD, discusses his recent study examining hemodynamics in patients undergoing high-risk PCI with mechanical circulatory support (MCS). Dr. Basir is the director of MCS at Henry Ford Hospital in Detroit, MI.
Dr. Basir studied logs collected from the Automated Impella Controller™ (AIC) during Impella® support in 300 patients from the PROTECT III study. “The AIC log captures all of the invasive hemodynamics from the pump itself,” Dr. Basir explains. “We actually found that about half of the patients had loss of pulsatility.” Dr. Basir defines loss of pulsatility as patients having a narrow blood pressure with less than 20 mmHg difference in terms of their pulse pressure. “So these patients were essentially dependent on their device,” states Basir, “and that’s an important finding because what it shows is actually the appropriateness of Impella use within this really sick cohort of patients.”
Looking at the characteristics of the patients who lost pulsatility, Dr. Basir reports, “the loss of pulsatility, or the dependence on the support device, isn’t related to their age, or their fragility; it’s not associated with the anatomic complexity. It’s all about hemodynamics.” He states that loss of pulsatility was associated with lower mean arterial pressure (MAP), systolic blood pressure, cardiac output (CO), cardiac index (CI), and higher cardiac output deficit. He explains that cardiac output deficit is a calculation to predict the CO that a patient potentially needs. “So you use your target cardiac output, or your predicted cardiac output, which is 2.2 times your body surface area. You then subtract it by the actual cardiac output that you measure with a Swan-Ganz catheter, for example, and you look at what that cardiac output difference is… So the larger the cardiac output deficit is, the higher level of support that you need.”
Dr. Basir explains that hemodynamics can help clinicians determine when to use hemodynamic support for Protected PCI. “If you have a cardiac output deficit, and you’re doing a complex PCI, you really need support.” He also emphasizes that loss of pulsatility is an important marker for downstream prognosis and risk of cardiovascular adverse events at 30 and 90 days.
Following a brief discussion with interviewer George Vetrovec, MD, MACC, MSCAI, regarding studies evaluating the use of right heart catheterization, Dr. Basir concludes, “If you’re doing a complex PCI, you need to know the underlying hemodynamics because those patients who have borderline hemodynamics are likely going to do better with hemodynamic support up front.”