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Among patients with cardiogenic shock, vasopressin administration in the first 24 hours was linked to lower in-hospital mortality, according to a recent study.

In a study of patients with cardiogenic shock (CS), vasopressin administration in the first 24 hours was linked to lower adjusted in-hospital mortality, particularly among those requiring high-dose vasopressors (HDVs), according to findings published in American Heart Journal.

“Classic cardiogenic shock (CS) is characterized by reduced cardiac output with elevated systemic vascular resistance, but a high-risk subset of patients with CS develops inappropriate systemic vasodilation and mixed shock requiring high vasopressor doses,” wrote Dhruv Sarma, BMBCh, Mayo Clinic, and colleagues. “While catecholamines such as norepinephrine are currently the first-line medical therapy for CS, they are associated with several adverse effects …” Understanding this, the authors researched the utility of vasopressin as an adjunctive, catecholamine-sparing vasopressor in CS.

Study Design & Patient Population

The study involved 721 adult patients admitted to the Mayo Clinic Cardiac Intensive Care Unit between 2007 and 2015 with CS requiring vasopressor therapy. Vasopressin was administered to 207 patients (29%) within 24 hours of admission. High-dose vasopressor therapy was defined as a norepinephrine equivalent dose of at least 0.3 μg/kg/min.

Multivariable logistic regression and propensity score analysis were employed to estimate odds ratios (ORs) and 95% CIs for in-hospital mortality, both before and after adjusting for relevant covariates.

“Given the paucity of current data, we investigated outcomes associated with vasopressin use in a larger mixed cohort of patients with CS across a range of shock severity and etiologies,” the authors noted.

Survival Benefit With Vasopressin

Overall in-hospital mortality stood at 38.1%, rising to 56.8% among those receiving HDVs versus 29.2% in recipients of lower doses. In the full cohort, vasopressin was linked to lower adjusted mortality (adjusted OR, 0.61; 95% CI, 0.38-0.96; P=0.036) after accounting for illness severity and other covariates. This association persisted after further propensity adjustment (adjusted OR, 0.59; 95% CI, 0.35-0.99; P=0.05).

The mortality benefit was most pronounced in the HDV subgroup: recipients of vasopressin had a significantly lower risk of death (unadjusted OR, 0.54; 95% CI, 0.32-0.92; P=0.02). “Our findings suggest that the use of vasopressin in CS may merit prospective evaluation, particularly among those patients who require treatment with HDV,” the authors concluded.

Mechanistic Rationale

The study highlights the potential benefits of vasopressin beyond traditional catecholamine therapy, noting that vasopressin’s unique pharmacology may explain its advantages. Although catecholamines such as norepinephrine remain first-line treatment for CS, high doses can precipitate tachycardia, arrhythmias, and increased myocardial oxygen demand. Vasopressin may counteract these effects by raising systemic vascular resistance without significant chronotropic or inotropic activity.

“Adjunctive vasopressin is commonly used to manage vasoplegic shock after cardiac surgery or due to sepsis,” the authors explained. “It remains unclear whether certain CS phenotypes are characterized by a relative vasopressin deficiency that could be targeted by its use as an adjunctive vasopressor.”

By augmenting systemic vascular resistance without significant chronotropic or inotropic effects, vasopressin may spare catecholamine exposure and mitigate associated risks.

Limitations & Future Direction

Several study limitations must be considered, according to the authors.

• Because it is a retrospective study without a standardized protocol for vasopressor use, unmeasured confounding may persist.
• Changes in cardiogenic shock management practices over the study period could limit the generalizability of the findings.
• Although the mortality benefit persisted even in patients without documented sepsis, the study lacked invasive hemodynamic data to precisely categorize shock subtypes.

“Prospective trials will be needed to validate these findings and to better define the optimal patient population for vasopressin therapy in CS,” the team advised.

Pending prospective randomized data, these results suggest that early vasopressin administration may be considered for patients with CS, especially those who develop refractory shock requiring HDVs, according to the authors. “Given the high mortality of CS and the limitations of current therapies, the adjunctive use of vasopressin deserves further study,” the researchers concluded.