Impact of the MELD Score for Risk Stratification in Cardiac Surgery

Objectives: The outcome of the patients undergoing cardiac surgery with cardiopulmonary bypass (CPB) is also influenced by the renal and hepatic organ functions. Risk stratification, using scores such as EURO Score II or STS PROM for patients undergoing cardiac surgery with cardiopulmonary bypass, ignore the quantitative renal and hepatic function; therefore, MELD score was applied in these cases.

Methods: We retrospectively examined patient data using the MELD score as a predictor of mortality. Data of 11.434 adult patients undergoing cardiac surgery with CPB, from 2000 to 2019 was examined. Patients were divided into 5 categories based on their MELD score (<10, 10–19, 20–29, 30–39 and 40+). Total clinical mortality and mortality at 30 days for every category was calculated. Furthermore, we calculated similar mortality rates for patients with preoperative diagnosed liver cirrhosis.

Result: The 30-day mortality and total clinical mortality for patients with respect to their MELD scores is as follows:

MELD score	patients	30-d mortality [%]	n	Total clinical mortality [%]	n
<10	9.372	4.1	384	4.0	378
10–19	1.713	15.0	257	16.5	282
20–29	300	25.0	75	27.7	83
30–39	45	35.6	16	48.9	22
>40	4	100	4	100	4
Total	11.434	6.4	736	6.7	769

The 30-day mortality of all patients (n = 11.434) was 6.4%. Mortality rises by ~10% for every 10 points of MELD Score. Furthermore, the mortality rate for patients with diagnosed liver cirrhosis was 33.3% (at 30 days) and 31.3% (total clinical mortality).

Conclusion: A higher mortality was observed in patients with reduced liver and renal function, with a significant increase in patients with a MELD score >20 and those diagnosed with liver cirrhosis. As the current risk stratification scores do not consider this, we recommend the applying the MELD score before considering patients for cardiac surgery.

Publication History

Article published online:
19 February 2021