[Too many heart catheter procedures in Germany ?]

Study protocol for a matter of heart: a qualitative study of patient factors driving overuse of cardiac catheterisation

INTRODUCTION

Overuse of cardiac catheterisation (CC) for stable coronary artery disease (CAD) is documented in Germany and other regions, although percutaneous coronary interventions do not provide a benefit over medical therapy for stable patients. Various studies investigated health system, physician and patient factors driving non-adherence to guidelines which recommend a stepwise approach with invasive procedures only in case of signs of ischaemia in non-invasive testing. In a larger-scale project, we aim to better understand the patients' perspective in order to develop an intervention that enhances patient's acceptance of this stepwise diagnostic approach for stable CAD. As a first step, this qualitative study aims to identify patient factors that prevent and promote the described overuse.

METHODS AND ANALYSIS

The exploratory qualitative interview study will include about 20 patients with stable CAD and a history of acute coronary syndrome from two German teaching practices. Narrative, structured interviews designed to last 30 to 90 min will be conducted. The interviews will be analysed using qualitative content analysis by Mayring. The analysis will address the following questions: (1) What are reasons for stable patients to undergo CC? (2) How do patients deal with their heart disease (secondary prevention)? (3) Which processes do patients describe regarding decision-making for non-invasive and invasive coronary procedures? (4) What information needs exist on behalf of patients to better understand the stepwise diagnostic approach outlined in guidelines and thereby avoid low-appropriate CCs? Based on these data, empirical typification will be conducted.

ETHICS AND DISSEMINATION

Ethical approval for the study was obtained. All participants will provide written informed consent. Data will be pseudonymised for analysis. The findings will contribute to the development of an appropriate intervention. Results will be disseminated by conference presentations and journal publications.

[Left-heart catheterization followed by other invasive procedures: Regional comparisons reveal peculiar differences]

BACKGROUND AND AIMS

Diagnostic left heart catheterization (LHC) is recommended if the therapeutic consequences of a bypass operation or percutaneous coronary intervention (PCI) are being considered. The present study examines regional differences in healthcare provision and therapeutic consequences of LHC, differentiated by counties and hospitals of the German federal state of Saxony-Anhalt. In addition, it looks at which patient-related factors influence the proportion of follow-up interventions. The relation between the rates of LHC, interventions and hospital discharge due to myocardial infarction is examined.

METHODS

The data of 9,791 individuals having statutory health insurance coverage by the AOK Saxony-Anhalt with 10,906 anonymized inpatient cases of LHCs in 2011 were followed until 12/31/2012, and it was examined whether they subsequently received a coronary bypass or PCI. The data was used to compare both the counties of Saxony-Anhalt (according to residence, adjusted for age and sex) and their hospitals. Regression analysis was run to identify determinants of receiving a LHC without consequences.

RESULTS

Overall, 54.2 % of the patients with LHC had no invasive follow-up intervention. Regression analysis showed an approximately linear relationship for the counties: the number of LHCs provided correlates with the number of LHCs requiring no PCI or bypass within a period of at least 12 months. Regional LHC rates are not correlated with hospitalizations due to acute myocardial infarction. No bypass or PCI in the follow-up period was reported for 37 to 85 % of the cases, depending on the hospital providing the LHC. Women and younger patients have a higher risk to undergo LHC without therapeutic impact.

DISCUSSION

The analysis indicates that there are specific regions in Saxony-Anhalt and diagnoses where the indications for LHC should be more conservative. However, more detailed analyses are needed to verify the identified potentials for improving healthcare provision.