Characteristics of Cardiogenic Shock Subtypes for Guiding Clinical Practice
- Patients with cardiogenic shock (CS) due to end-stage heart failure (ESHF) who receive mechanical circulatory support (MSC) have lower global oxygen delivery, greater anaerobic metabolism, lower pulmonary capacitance, and higher pulmonary vascular resistance than patients with CS due to acute myocardial infraction (AMI).
Table 1. Types of Supporta
|Primary Support (n, %)||CS Due to AMI (n = 26)||CS Due to ESHF (n = 42)|
|Impella||5 (20%)||3 (7%)|
|VA ECMO||13 (50%)||17 (40%)|
|BIVAD||4 (15%)||19 (46%)|
aData from Lim et al1
Patients with CS due to ESHF had significantly lower ejection fraction compared with patients with CS due to AMI (13±2 vs 25±3, respectively; P<0.001). Additionally, patients in the ESHF group presented with lower pulmonary capacitance (1.33±0.20 vs 2.18±0.28 ml/mmHg, P<0.001) and higher pulmonary vascular resistance (3.72±0.52 vs 2.23±0.23 WU, P<0.001).
The Impella CP device was inserted through the femoral vessels in all cases. Two lower-limb amputations occurred with VA ECMO vs 0 amputations in the Impella heart pump group.
While ESHF patients had greater anaerobic metabolism than AMI patients, those with ESHF vs AMI exhibited different patterns of metabolic derangement with significant differences in pH (ESHF [7.32±0.09] vs AMI [7.20±0.02]; P<0.001), sodium (ESHF [129.7±1.1] vs AMI [137.2±1.0]; P<0.001), and chloride (ESHF [91.9±0.8] vs AMI [101.9±1.0]; P<0.001) ions.
According to the investigators, this study highlights the importance of understanding the “phenotypic differences [which] may guide intervention based on the underlying etiology of cardiogenic shock.”
This study is limited by its small sample size as well as its single-center design. Despite this limitation, this study provides greater insight into the characteristics of highly selected CS patients with ESHF and AMI than previously published research.
- Lim HS, Howell N. Cardiogenic Shock Due to End-Stage Heart Failure and Acute Myocardial Infarction: Characteristics and Outcome of Temporary Mechanical Circulatory Support. Shock [published online November 3, 2017]. doi: 10.1097/SHK.0000000000001052.
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