HF Rate Has Held Steady for 20 Years
The incidence of heart failure has not improved over the past 20 years, according to Veronique L. Roger, M.D., of the Mayo Clinic, Rochester, Minn., and her associates.
The researchers conducted a community-based study to examine trends in heart failure (HF), hoping to avoid the selection biases shown to be present in previous studies of the issue. They studied a cohort of 4,537 cases that were first diagnosed in one Minnesota county between 1979 and 2000, a population with characteristics similar to those of whites across the United States but not to those of other racial groups.
The incidence of HF did not decrease appreciably over these 2 decades, ranging from 360/100,000 men in 1979-1984 to 383/100,000 men in 1996-2000 and from 284/100,000 women to 315/100,000 women in those same periods (JAMA 2004;292:344-50).
Overall HF mortality improved somewhat, from 57% in 1979-1984 to 48% in 1996-2000. However, improvements were not equal across different age groups and genders. Only the youngest men showed improved survival, while women and elderly people of both sexes had steady mortality over the 20-year study period.
A full 42% of cases were diagnosed as outpatients, and 26% of these patients were never hospitalized for their HF. Thus, hospital-based surveillance programs and studies based on inpatient data fail to identify a significant portion of HF cases, the investigators noted.
Pericardial Valves Superior to Porcine
Second-generation pericardial valves are more durable than traditional porcine valves as aortic valve replacements, said Guangqiang Gao, M.D., and associates at Providence Health System, Portland, Ore.
The first generation of pericardial valves was taken off the market because of the high rate of structural failure. The second generation was marketed in 1991 in the United States but has not been as widely used as porcine valves, largely because of the poor history of its predecessors. Dr. Gao and associates compared the two types of valve by reviewing the experience at their facility with all 518 aortic valve replacements using porcine valves, which were done between 1974 and 1996, and all 1,021 aortic valve replacements using second-generation pericardial valves, which were done between 1991 and 2002 (J. Am. Coll. Cardiol. 2004;44:384-8).
Overall late survival rates were similar between the two groups, as was freedom from valve-related complications such as thromboembolic events and endocarditis. But the estimated 10-year rate of explantation was much higher for porcine (10%) than for pericardial valves (3%). Only four pericardial valves required replacement because of structural deterioration.
When Thrombolysis Is the Sole Option
For acute MI patients who either can't afford invasive intervention or don't have ready access to a hospital with a cath lab, medical thrombolysis is the only viable option. Fortunately, it has proved beneficial to most such patients, either as a definitive treatment or as a bridge to later intervention, according to Rami Khouzam, M.D., of the Tucson Hospitals Medical Education Program, and his associates.
The investigators reviewed the experience of 42 MI patients treated between 1999 and 2002 at a small county hospital in southern Arizona that offered only thrombolysis. MI patients in whom thrombolysis produced resolution of ST-segment changes within 90 minutes had a very high likelihood of a patent infarct artery and a very low mortality. Further PCI would be unlikely to improve their outcome. In contrast, those in whom thrombolysis did not produce ST-segment resolution within 90 minutes had a 40% probability for an occluded artery and required transfer for “rescue” PCI, the researchers said (Chest 2004;126:457-60).
Gemfibrozil Does Not Slow Renal Decline
Even though gemfibrozil cuts triglyceride and total cholesterol levels while raising HDL cholesterol, it does not slow renal decline in patients with mild renal insufficiency and concomitant coronary disease, reported Marcello Tonelli, M.D., of the University of Alberta, Edmonton, and his associates.
The researchers analyzed data from a trial conducted at 20 Veterans Affairs medical centers involving 399 subjects with both coronary heart disease and renal insufficiency (Am. J. Kidney Dis. 2004;44:832-9).
Compared with placebo, gemfibrozil (Lopid) cut triglycerides by 55.0 mg/dL, cut total cholesterol by 6.7 mg/dL, and raised HDL cholesterol by 2.3 mg/dL. But it did not slow the decline of renal function or improve subjects' chances of progressing to moderate or severe renal insufficiency.
Both gemfibrozil and statins improved cardiovascular outcomes in this population, but it appears that only statins exert renal benefits as well.