New Developments in Congestive Heart Failure: The Use of Ultrafiltration

With the System 100, physicians specify the amount of fluid to be extracted from a patient’s blood at a controlled rate. Vascular access is established via a patient’s peripheral veins, typically in the arms. The system uses a technique called ultrafiltration, which separates excess fluid from the blood. Up to four liters of excess fluid can be removed in up to an eight-hour period using the System 100. The System 100 has been shown to have no impact on electrolyte balance, blood pressure or heart rate of clinical significance. While many health conditions can cause fluid overload, including renal failure, post-surgical fluid overload and metabolic disease, congestive heart failure is the leading cause of fluid overload. CHF Solutions feels that fluid removal therapy using the System 100 can lower related health care costs and improve the quality of life for patients suffering from fluid overload. We’ve made so much progress in cardiology…why is CHF such an issue? As you know, there’s good news and bad news about our progress in treating heart disease. With an increased understanding of the process of atherosclerosis and the broad range of lipid management drugs, we’re able slow down the progression of atherosclerosis. We’ve also known for years about the long-term negative effects of high blood pressure and there is a huge range of medications to reduce blood pressure with minimal side effects. Regarding acute myocardial infarction (AMI), with the use of clot-busting agents and emergency angioplasty and stenting, we have dramatically improved the survival rate of AMI patients. Unfortunately, in the area of congestive heart failure, the progress hasn’t been as dramatic, and in fact, the incidence of heart failure is growing dramatically as the population ages. Ironically, the effects of long-term hypertension and/or surviving AMI are often the precipitating event towards heart failure: reduced cardiac output. The body has an automated response to reduced cardiac output; the most insidious aspect is the vicious cycle of the cardio-renal system and the subsequent activation of the neurohormonal system. The activation of the neurohormonal system is thought to lead to pathological fluid retention and remodeling of the heart. We can treat many of the symptoms of heart failure, but we’re a long ways off from a cure. That’s why new technologies are so exciting, such as LVADs for the very sickest heart failure patients; biventricular pacing for the small subset of patients who seem to benefit from it; and simplified ultrafiltration such as the System 100 that can be applied to a broad range of congestive heart failure patients with fluid overload. What is the perspective of the hospital when it comes to treating these patients? CHF is a big issue for most hospitals. For virtually all hospitals, it shows up as being one of the top three DRGs (DRG 127, heart failure and cardiac shock). Heart failure represents roughly 2.2 million admissions per year and it costs the health care system roughly $23 billion to treat these patients. Further, there is a subgroup of 200,000 Class IV patients that account for 800,000 admissions. Unfortunately, while this group of 200,000 represents only 13% of the CHF patient population, they are responsible for almost 50% of the cost of CHF hospitalizations due to complications like pulmonary edema and other co-morbidities associated with very sick CHF patients. Unfortunately, many hospitals lose money on the reimbursement. From what we understand from national databases, the average length of stay is roughly six days, at a cost of approximately $10,000; the average national reimbursement for DRG 127 is just under $5,000. Some hospitals have a better control of their costs than others, but it’s a constant battle. Why do we need new treatment options? Well, first of all, let’s remember that there is not a cure for heart failure, nor does there appear to be anything on the horizon. It is a progressive condition with four classes of severity by the time patients reach class IV and even class III, they’re prone to frequent hospitalizations, due primarily to acute fluid overload. Many of these hospitalizations are due to lifestyle factors (noncompliance with medications or diet) but a lot of it is due to the body’s resistance to their oral medications diuretics in particular. And while there are a lot of tricks to managing their medications, the body is going to eventually win and overwhelm the diuretic therapy. Therefore, to have a treatment option other than an IV formulation of the very drug that they’ve failed is a major benefit. We still have a lot to learn about ultrafiltration therapy, but there are some very exciting possible benefits based on previous studies: first, ultrafiltration does not appear to activate the neurohormonal system. By giving the kidneys a diuretic holiday, it appears that the body gets recalibrated and will respond to lower doses of the oral diuretics after a course of ultrafiltration treatment. This is a ways from curing heart failure but it could be a major benefit for patients as we seek to slow down the progression of their condition, improve their quality of life and keep them stable for a longer period of time. So, what role will ultrafiltration play in all this? Well, the symptom that typically drives these patients into the hospital is acute fluid overload. As I mentioned, the current treatment is to put them on an IV form of the diuretic that has already failed them. They need to titrate the diuretic dose with some caution since if you over-diurese them hit ‘em too hard, too fast they can become hypotensive and/or run an increased risk of arrhythmias. Therefore, it may take 2-4 days to remove the 2-4 liters of excess fluid using IV diuretics. With ultrafiltration, you can safely, precisely and rapidly remove excess fluid from the blood stream. The only limitation is how quickly the patient can recruit or mobilize the excess fluid from the interstitial spaces throughout the body and transfer it to the bloodstream. Our results show us pretty consistently that we can safely remove up to four liters of excess fluid in up to eight hours of treatment. Therefore, as you can see, the clinician benefits from rapidly removing excess fluid so that they can immediately begin to adjust medication dosages; the patient benefits by a rapid relief of symptoms; and the hospitals and payors benefit by potentially reducing the length of stay in the hospital, or at least reducing the time spent in more intense environments like the ICU or CCU. What about hemodynamic parameters or electrolyte balance? Aren’t these issues to address when removing excess fluid? The good news is that our clinical results to date have shown no impact on blood pressure or heart rate. Furthermore, since the balance of electrolytes is the same in the blood stream as it is in the isotonic fluid we remove, we don’t disrupt the balance of electrolytes. Nurses especially appreciate not having to chase K (potassium) during our treatment. Removing 500 ml per hour of excess fluid from the blood stream via ultrafiltration has been proven to be a safe rate. Ultrafiltration has been proven to be safe? I’m glad you brought that up. Yes, ultrafiltration has been a well-documented technique in the treatment of fluid overload in CHF patients for 25-30 years. Several studies have shown its clinical efficacy as well as its safety profile. And even the ACC/AHA guidelines for the management of congestive heart failure state that the use of ultrafiltration can produce meaningful clinical benefits. So ultrafiltration is a well-known technique in the management of fluid overload in congestive heart failure. Then why isn’t ultrafiltration done all the time? Well, that’s a good question, but there’s an equally good answer: ultrafiltration in its present form (prior to our device) has been a challenging procedure, performed by nephrologists using hemodialysis/hemofiltration equipment. This has required a central line to be placed and treatment must be performed in the ICU under the care of a nephrologist with close scrutiny by a trained nephrology technician or nurse. Our device requires only peripheral access placed by an IV access team or PICC line nurse and can be performed virtually anywhere. It can be ordered by a cardiologist and requires minimal additional monitoring time by the nursing staff. Our System 100 can’t perform all the functions of the hemodialysis equipment but instead has been specialized to perform only ultrafiltration. We have several other advantages like a low-flow/low-volume blood circuit/filter but I don’t want to sound like a commercial…let’s just say it’s pretty cool technology that will likely have a broad range of uses. So there are other applications for this technology? Definitely. In fact, one of the interesting concepts involves the use of this technology to filter contrast from the blood during PCI. Contrast nephropathy is a significant clinical problem, especially in patients with baseline renal insufficiency and/or diabetes. Once contrast-induced renal failure occurs, it leads to much higher costs and mortality. If we can successfully develop this next generation of our technology, it may prove to be a huge benefit to patients, physicians and hospitals. Tell us about the start of CHF Solutions. Mark Gelfand and I co-founded CHF Solutions about three years ago. Mark has master’s degree in electrical engineering from the Leningrad Institute of Technology and has 15 years of experience in developing computer-controlled medical devices for life support. I got to know Mark years ago during our work together in the Division of Cardiology at The Johns Hopkins School of Medicine. Mark has a lot of industry experience, having worked at Nellcor-Puritan Bennett and was the co-founder and chief engineer for Cardiologic Systems, a medical device start-up. There is a recognized need for additional treatment options for heart failure. Nearly five million Americans are currently diagnosed with congestive heart failure. Approximately 550,000 new cases are diagnosed each year. It’s the largest single diagnosis-related group (DRG) in the Medicare system but most hospitals lose money on treating their heart failure patients due to reimbursement levels that do not match the cost of treating these patients. Not only are the statistics impressive (and scary), but my clinical experience in managing these patients through the end stages of their heart failure convinced me that new treatment options were necessary even earlier in their treatment.

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