Patients with cardiogenic shock (CS) who were monitored with a pulmonary artery catheter (PAC) had a lower incidence of short-term mortality, according to a systematic review and meta-analysis recently published in the Journal of Critical Care.
Time is of the essence in treating CS; death typically occurs very early in these patients, with half of them dying within the first 24 hours. Researchers have debated using PACs in the acute setting after several studies demonstrated neutral or adverse effects in critically ill patients, resulting in a reduction in their use in the intensive care unit. However, CS patients have been either excluded or vastly underrepresented in most of those studies. The authors sought to explore the prognostic implications of PACs in CS by reviewing adjusted observational studies focusing only on CS patients undergoing hemodynamic monitoring by PAC.
Short-term mortality was the primary endpoint of the analysis; the use of mechanical circulatory support devices was the secondary endpoint.
The investigators screened MEDLINE, EMBASE, the Cochrane Library, Web of Science, and abstract presentations at national and international congresses for appropriate studies from the inception of the analysis to December 2021. Only studies displaying adjusted results on short-term mortality were included in the meta-analysis. In all, 6 observational studies involving 1,166,762 patients with CS were chosen for the main study.
CS most commonly occurred after myocardial infarction in 75% [95% CI, 55%-89%] of the PAC cohort and 81% [95% CI, 47%-95%] of the non-PAC group. PAC was utilized in 33% (95% CI, 24%-44%) of all cases. After combining data adjusted for confounders, a significant relationship between the PAC group and a drop in short-term mortality appeared, compared with the non-PAC group (36% [95% CI, 27%-45%] vs 47% [95% CI, 35%-59%]; adjusted odds ratio (OR), 0.71 (95% CI, 0.59-0.87; P <.01). Mechanical circulatory support device use was significantly higher in the PAC cohort than in the non-PAC group (59% [95% CI, 54%-65%] vs 48% [95% CI, 43%- 53%]); OR, 1.60 [95% CI, 1.27-2.02; P <.01]).
Subanalyses conducted using different time-frames of the primary endpoint showed that invasive monitoring was significantly associated with a decline in in-hospital mortality (adjusted OR, 0.71; 95% CI, 0.57-0.89; P =.002). A nonsignificant association was observed for reduced 30-day mortality (adjusted OR, 0.77; 95% CI, 0.37-1.60; P =.48).
The study was limited by the heterogeneity and observational character of the included studies as well as by a lack of data about the pharmacologic and therapeutic management of the patients involved.
“Historically, acute myocardial infarction (AMI) has been the main cause of CS, but recent registries have shown a significant rise in the prevalence of non-AMI related CS,” the authors observed. “The rising burden of heart failure worldwide will probably increase this trend in the next years,” they added.
Bertaina M, Galluzzo A, Rossello X, et al. Prognostic implications of pulmonary artery catheter monitoring in patients with cardiogenic shock: a systematic review and meta-analysis of observational studies. J Crit Care. Published online March 25, 2022. doi:10.1016/j.jcrc.2022.154024