Do we need separate risk stratification models for hospital mortality after heart valve surgery?

BACKGROUND: The EuroSCORE (European System for Cardiac Operative Risk Evaluation) is often used to benchmark and predict hospital mortality after cardiac surgery. Based mainly upon coronary surgery patients, EuroSCORE may not be optimal for valve surgery patients. We evaluated the New York (NY) State dedicated valve surgery models and compared their performance to the EuroSCORE model. METHODS: Required model variables were collected prospectively for all patients, followed by calculation of predictive mortality rates using the logistic and additive EuroSCORE, the logistic and additive NY State models for valve surgery without concomitant coronary surgery (isolated valve surgery) and the logistic and additive NY State models for combined valve and coronary surgery. RESULTS: Observed mortality was 2.8% (25 of 904) for isolated valve surgery and 6.8% (27 of 395) for valve plus coronary surgery. Logistic NY State and EuroSCORE expected mortality for isolated valve surgery was respectively 3.0% and 6.1%, and for valve plus coronary surgery 5.9% and 7.8%. The logistic NY State model for isolated valve surgery showed better discrimination (c-index 0.86 versus 0.76) and calibration than the logistic EuroSCORE. Discriminatory power for the logistic NY State model for valve plus coronary surgery was comparable to the logistic EuroSCORE (c-index 0.74 versus 0.72), as was calibration. CONCLUSIONS: Our results suggest that dedicated risk models for valve surgery may be useful to provide more valid estimates of hospital mortality after heart valve surgery. Further exploration is needed to demonstrate general applicability of our results and assess the possible additional value of separate models for isolated valve surgery and valve plus coronary artery surgery, or aortic and mitral valve surgery, or both.

Is OpenSDE an alternative for dedicated medical research databases? An example in coronary surgery.

BACKGROUND: When using a conventional relational database approach to collect and query data in the context of specific clinical studies, a study with a new data set usually requires the design of a new database and entry forms. OpenSDE (SDE = Structured Data Entry) is intended to provide a flexible and intuitive way to create databases and entry forms for the collection of data in a structured format. This study illustrates the use of OpenSDE as a potential alternative to a conventional approach with respect to data modelling, database creation, data entry, and data extraction. METHODS: A database and entry forms are created using OpenSDE and MSAccess to support collection of coronary surgery data, based on the Adult Cardiac Surgery Data Set of the Society of Thoracic Surgeons. Data of 52 cases are entered and nine different queries are designed, and executed on both databases. RESULTS: Design of the data model and the creation of entry forms were experienced as more intuitive and less labor intensive with OpenSDE. Both resulting databases provided sufficient expressiveness to accommodate the data set. Data entry was more flexible with OpenSDE. Queries produced equal and correct results with comparable effort. CONCLUSION: For prospective studies involving well-defined and straight forward data sets, OpenSDE deserves to be considered as an alternative to the conventional approach.

The impact of the introduction of drug-eluting stents on the clinical practice of surgical and percutaneous treatment of coronary artery disease.

AIMS: Sirolimus-eluting stents (SES) have recently been shown to reduce restenosis in selected patients. The impact of this new stent on the use of coronary bypass graft (CABG) surgery or percutaneous coronary intervention (PCI) in clinical practice is yet unknown. Therefore, we investigated the impact of SES on the clinical practice of CABG and PCI in a series of unselected consecutive patients. METHODS AND RESULTS: Between April and October 2002, a policy of SES implantation for all procedures has been instituted in our hospital. In total, 798 patients were referred to PCI and 275 to CABG (SES group). A control group was composed of all interventions (806 PCI and 314 CABG) performed during the preceding 6 months (pre-SES). The main outcome was the occurrence of major adverse cardiac events (MACE) at 15 months. In the SES era, a significant shift was noted in the PCI group towards more multi-vessel stenting (28 vs. 24%; P<0.05), more bifurcation stenting (18 vs. 7%; P<0.0001), and the use of more stents (1.9 vs. 1.5; P<0.05). In the PCI elective patients, a shift was noted towards more three-vessel disease (pre-SES: 16% vs. SES: 23%; P=0.02). Furthermore, we observed a shift in the CABG group towards more impaired LV function (pre-SES: 34% vs. SES: 41%; P=0.02) and towards more three-vessel disease (pre-SES: 67% vs. SES: 75%; P=0.03). Overall, the cumulative MACE percentages at 1 year after coronary revascularization (PCI and CABG combined) decreased from 16.8 to 13.8% (P=0.03). The cumulative MACE percentages in the pure SES group and the pre-SES bare metal stent group at 12 months were 15.6 and 19.8%, respectively (P<0.01). CONCLUSION: The introduction of the SES has certainly had an impact on the treatment strategy of coronary artery disease (CAD). Increased use of these stents allows more complex coronary anatomy to be treated by PCI, and results in lower repeat revascularization rates.