The Impella hemodynamic support system is finding another niche: in patients who have suffered massive heart attacks complicated by cardiogenic shock.
Culture of continuous improvement
For the last two years, PinnacleHealth based in Harrisburg, Pa., has been placed among the top 100 hospitals by Thomson Reuters for superior performance in cardiovascular service and has twice received the Gold Performance Achievement Award from the American Heart Association for its Get With The Guidelines–Heart Failure program.
The healthcare institution has a certified Primary Stroke Center and recently opened an accredited Chest Pain Observation Unit. In 2002, physicians and staff from cardiology, emergency medicine and the surrounding community sought to improve their door-to-balloon times, which averaged 111 minutes. Today, about 97 percent of all STEMI code patients are seen within 62 minutes and the mortality rate is down to 2.8 percent, says Philip W. Guarneschelli, acting president and CEO of PinnacleHealth.
"We are a quality-driven and evidenced-based organization," Guarneschelli says. "We aggressively assess ourselves and try to improve upon our benchmarks annually."
One of PinnacleHealth's latest efforts to advance patient care is the Heart Recovery Program, which includes advanced training in hemodynamic support and complex patient management to better facilitate heart muscle recovery. The program, started in August 2010, targets high-risk patients. An especially difficult patient population to treat involves those patients with massive heart attacks complicated by hemodynamic instability. Statistically, more than half of these patients will die—an average that hasn't changed in two decades despite improvements in PCI techniques and protocols.
The program benefits from use of a new tool, the Impella 2.5, which is percutaneously inserted via the femoral artery into the left ventricle and pumps 2.5 liters of blood per minute (l/min).
"This is a new arena for interventional cardiologists," says Brijeshwar Maini, MD, chair of the structural heart program at PinnacleHealth. "Ventricular assist devices have always been part of the surgical field. It's a new concept, however, for cardiologists to make a decision to put in an active assist device. It gives the interventional cardiologist a new tool to intervene in the cycle of shock earlier, thereby improving outcomes for these patients."
Preliminary data from the USpella registry, reported by Maini at TCT10, found after prophylactic Impella-supported revascularization in complex PCI cases:
- Significant improvement (17 percent) of left ventricular ejection fraction (LVEF);
- Significant improvement (49 percent of patients) in NYHA class with a 61 percent reduction in NYHA Class IV;
- Significant reduction (25 percent) in implantable cardioverter-defibrillator (ICD) target population;
- More than half of the patients (54 percent) were turned down for CABG and 59 percent of the patients had experienced a prior MI; and
- Low mortality (3.9 percent) and MACE rate (8.2 percent) in patients compared with literature on patients with high-risk PCI (Cardiovasc Revasc Med 2010;11(2):91-97).
- Findings after emergent Impella support in high-risk patients with STEMI and/or cardiogenic shock included:
- Hemodynamic support (cardiac index, cardiac power output, wedge pressure, mean arterial pressure) significantly improved;
- Cardiac power output, a strong correlate of in-hospital mortality, increased from 0.5 to 1.0 while on the device;
- Significant improvement (19 percent) of LVEF at discharge; and
- Ninety percent of the survivors recovered native cardiac function and were discharged with their own hearts.
The registry, which receives data from 24 U.S. and Canadian centers, consisted of 352 patients supported with the Impella at the time of the TCT10 presentation.
"More ischemia leads to more ischemia; it's a downward spiral," says Maini. "If we can provide a cardiac output of 2.5 liters of blood per minute, we won't deprive end organs of the necessary blood volumes. With that concept in mind, we have felt that the Impella device is a good tool to use in patients who are in extremis."
These data are quite promising and will be further elucidated through the registry. Also, early insights to PROTECT II, the randomized controlled trial comparing Impella 2.5 with the intra-aortic balloon pump (IABP), are promising. These results will be presented at ACC 2011 this month.
Coordinated multidisciplinary effort