Appropriateness of invasive cardiovascular interventions in German hospitals (2000 - 2001): an evaluation

It is known that cardiovascular intervention rates vary widely among countries [[1]] and are not explained by geographical variations in the incidence of coronary artery disease. Among other explanations, two hypotheses are frequently put forward to answer this discrepancy; high rates of unnecessary procedures in those countries with a high per capita rate of interventions, and inappropriately high threshold in low frequency areas, rather than overuse elsewhere.

The latter view is supported by previous studies from North America [[2]] and a recent United Kingdom study suggested that under-use of revascularisation results in preventable morbidity and mortality [[3]].

Gandjour and colleagues from Cologne in Germany have performed a study where the appropriateness of invasive cardiovascular interventions in Germany hospitals have been studied for the years 2000 and 2001 using the RAND/UCLA appropriateness criteria [[4]]. As the authors indicate in their article, the validity of the RAND/UCLA criteria to measure the appropriateness of coronary artery bypass grafting (CABG), percutaneous transluminal coronary angioplasty (PTCA) and carotid endarteriectomy (CEA) has been demonstrated in a variety of studies. In addition, the RAND/UCLA test has been used for investigating a potential overuse of coronary revascularisation and CEAs in several countries, including Canada, Italy, the Netherlands, Spain, the United Kingdom, the United States and Germany. Even though widely used, Shekelle et al. [[5]] have pointed out that the reproducibility of the RAND/UCLA criteria is excellent but not perfect. Therefore, a European panel with experts from the Netherlands, Spain, Sweden, Switzerland, and the United Kingdom revised the RAND appropriateness criteria for PTCAs and CABGs [[6]]. These revised RAND criteria have now been used by Gandjour and collegues in a retrospective study from 12/2000 to 08/2001. A total of 361 patients were enrolled treated in 121 hospitals providing information on the appropriateness of 128 PTCAs, 92 GABGs and 220 CEAs.

In their study they found that inappropriateness rates were only 2 % (95 % CI 0 - 5 %), 4 % (95 % CI 1 - 9 %), and 3 % (95 % CI 1 - 7 %) for PTCA, CABG, and CEA, respectively. However, the rate of uncertain procedures was 41 % (53/128) for PTCA, 41 % (58/141) for CEA and only 23 % (21/92) for CABG.

Only 38 % (95 % CI 32 - 45 %) of patients who received a coronary intervention had had a pre-interventional stress test [[4]].

From their data the authors concluded that the study yielded little overt overuse in the performance of PTCA, CABG, and CEA, but potentially large underuse of stress tests. Despite a high per capita rate of invasive cardiovascular interventions in Germany the rate of inappropriate procedures was not larger than in other countries [[4]]. As the authors point out their results for PTCA are similar to those data obtained by two previous studies in Germany, which yielded relatively low inappropriateness rates (1 % and 10 %, respectively) [[7], [8]].

Even when taking all shortcoming and drawbacks of the study (as listed by the authors in the paper) into account, the report is important for several reasons:

The data show low inappropriateness rates for PTCA, CABG and CEA. Taking the high per capita rate of invasive cardiovascular interventions in Germany, the lower rate of these interventions in other European countries may be explained by a higher rate of underuse [4]. In addition the suspicion that a large overuse of these procedures exists is not supported by the data. But the study should also be the impetus for further strengthening the indications for these procedures among cardiologists, cardiac surgeons, neurologists and vascular surgeons. The fast development of innovations both in interventional and surgical cardiovascular treatment options and new health care strategies make interdisciplinary conferences even more important than in the past. The data show only a 13 % rate of PTCA for three-vessel disease, which is lower than the 27 % rate of the PTCA register [9]. Conversely, the CABG rate in this group was 46 % [4]. This underscores the importance of CABG in patients with three-vessel disease. A follow-up study should be performed about the long-term outcome of those patients receiving and not receiving the appropriate treatment for their disease. A study from Los Angeles, California has shown that patients who received the necessary revascularisation within 1 year of angiography had lower mortality rates than those who did not (8.7 % vs. 15.8 %, p = 0.01) and had less chest pain at follow-up p < 0.03) [10]. Adverse clinical outcome for patients with underuse of coronary revascularisation was also reported in the study by Hemingway and associates [3]. The high rate of uncertain procedures, especially for PTCA (41 %) and CEA (41 %) and less for CABG (23 %) has been also confirmed by others, e.g. for PTCA [11]; it is the task of the cardiologists and cardiovascular surgeons to control the strict adherence to accepted indication criteria and that the percentage of uncertain procedures is going to be reduced. The fact that patients are treated interventionally with a high number of stents in a diffuse three-vessel disease is probably not appropriate. Even though the DRG system may clarify these discrepancies, the decision about the indication should be done by physicians in interdisciplinary conferences. The low number of stress tests performed should be evaluated and further reduced by the cardiologists community.

In conclusion, the report by Gandjour and coworkers show that there is a low percentage of inappropriate procedures for PTCA, CABG and CEA done in Germany in the years 2000 - 2001. However, the high number of uncertain procedures for PTCA and CEA have to be further evaluated by the respective scientific societies.

References

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