Septic cardiomyopathy: hemodynamic quantification, occurrence, and prognostic implications

Abstract

Introduction: In sepsis, severe reduction of afterload may often mask cardiac impairment. By establishing the parameter "afterload-related cardiac performance (ACP)" we wanted to determine the extent, frequency, and prognostic relevance of septic cardiomyopathy.

Methods: Over a 12 months period, all patients of our medical intensive care ward were included into the study when they were classified as having "septic MODS" (sepsis score ≥12 as long as APACHE II score was ≥20). Hemodynamic assessments were performed using a pulmonary artery catheter.

Results: A total of 524 patients were screened, and from these 39 had septic MODS. In survivors, APACHE II score values declined from day 0 (day of diagnosis, 27.6 ± 8.0) to day 4 (17.8 ± 8.0), while in non-survivors, score values remained high (day 0: 31.8 ± 5.7; day 4: 33.2 ± 6.7; p < 0.001). Hemodynamic measurements showed an inverse correlation of cardiac output (CO(measured)) and SVR which can be described as CO = β (0) × SVR( β1). The upper limit of 80% tolerance range of CO was defined as the "normal" CO values (CO(normal)). The parameter "afterload-related cardiac performance (ACP)" was calculated as ACP (%) = CO(measured)/CO(normal) × 100. It turned out that ACP shows a stronger correlation with APACHE II- and sepsis-score than CO, cardiac index (CI), cardiac power (CPO), or cardiac power index (CPI). Furthermore, ACP correlated with sepsis-induced myocardial damage as indicated by elevations of troponin I and significantly differed between surviving (86.9 ± 1.6%) and non-surviving patients (69.2 ± 1.4%; p < 0.0001). While 75% of the surviving patients showed an ACP >60%, 38% of the non-survivors had a moderate (ACP 40-60%) and 25% a severe impairment of cardiac function (ACP < 40%).

Conclusion: By using the parameter "afterload-related cardiac performance, ACP", the impairment of cardiac function can be reliably quantified showing that septic cardiomyopathy occurs frequently and is of prognostic relevance in patients with septic MODS.