It has become increasingly evident that there has been a significant shift in the long-term mortality of patients admitted to the hospital with heart failure. Discharge from the hospital after an acute event often leads to a revolving door, returning the patients back into the hospital with recurrent symptoms.
There is little question that the current guideline-driven therapy of beta-blockers, ACE inhibitors, and aldosterone receptor blockers have had a significant impact on chronic heart failure therapy. Yet there are almost 1 million first and readmissions annually to U.S. hospitals with the primary diagnosis of heart failure, our nation's most common admitting diagnosis. Despite increased adherence and the success of guideline therapy and inpatient educational efforts, heart failure specialists continue to be faced with an unacceptable early mortality and 60-day readmission rate of 35%.
A recent trended temporal analysis of outcomes of hospitalized patients with heart failure between 1993 and 2006 provides both good and bad news. During that period, in-hospital mortality decreased from 8.5% to 4.3%. But the 30-day postdischarge mortality rate increased from 4.3% to 6.4%. The postdischarge mortality rate during the 30 days post discharge now exceeds the in-patient mortality. During the same 30-day period, the readmission rate increased from 17.2% to 20.1%. Associated with these outcomes, the authors point out that there had been a significant shortening of the length of stay from 8.8 days in 1993 to 6.3 days in 2006 (JAMA 2010;303:2141-7). This shortened hospital stay is largely driven by Medicare reimbursement rates. Their analysis raises important question in regard to the potential effect of the shortening of hospital stay on postdischarge events.
Several studies have examined inpatient care as it affects readmission rates. All of these studies have indicated increase compliance to guideline therapy. However, one rather striking observation has been the failure to achieve weight loss or diuresis during hospitalization. The ADHERE registry points out that 53% of patients admitted with acute congestive heart failure, presumably with volume overload, lose less than 5 pounds, and 20% actually gain weight. It is true that some heart failure may be related to causes other than fluid accumulation, but for the vast majority of patients fluid accumulation represents the primary precipitating event leading to acute heart failure. It is quite possible that the shortened hospital stay leads to premature discharge before adequate diuresis can be achieved. I have found it difficult if not impossible to obtain daily weights in the hospital, and actually urge all of my patients to buy a scale and use it to adjust their diuretic program at home. A novel idea like this would probably not be allowed in the hospital.
A subtle increase in fluid retention associated with increase in pulmonary artery pressure preceding the acute exacerbation of heart failure has been observed in a number of studies using implantable devices. These devices can continuously monitor pulmonary fluid volume and pulmonary artery pressure. Research has been carried out using pulmonary impedance measurements in an attempt to continuously measuring pulmonary fluid. Some of these devices have been incorporated into pacemaker-defibrillator devices, but as yet have not been approved for clinical use. The CHAMPION trial recently reported at the European Heart Failure Society meeting reported that using a totally implantable pulmonary artery pressure sensor in patients with NYHA Class III patients led to improvement in heart failure outcomes. In a small randomized study over a 60-day period of follow-up, symptomatic improvement and the need for rehospitalization was observed.
The issue of early readmission and mortality after acute therapy remains a dilemma facing the hospitalists, internists, and family physicians who treat most of these patients. A careful assessment of the early discharge policies is in order. The mantra of expeditious hospital discharge may be incriminated in the readmission and mortality outcomes. It is also possible that physicians are not aggressive enough with diuretic therapy, both in the hospital and after discharge. Whether an implantable pulmonary artery sensor will replace the bathroom scale remains to be seen. I have observed over time, much to my displeasure, that my bathroom scale never lies.