Epidemiology and outcomes of pulmonary hypertension in the cardiac intensive care unit

Aims: Pulmonary hypertension (PH) has been consistently associated with adverse outcomes in hospitalized patients. Limited epidemiologic data exist regarding PH in the cardiac intensive care unit (CICU) population. Here, we describe the prevalence, aetiology, and outcomes of PH in the CICU.

Methods and results: Cardiac intensive care unit patients admitted from 2007 to 2018 who had right ventricular systolic pressure (RVSP) measured via transthoracic echocardiography near CICU admission were included. PH was defined as RVSP >35 mmHg, and moderate-to-severe PH as RVSP ≥50 mmHg. Predictors of in-hospital mortality were determined using multivariable logistic regression. Among 5042 patients (mean age 69.4 ± 14.8 years; 41% females), PH was present in 3085 (61%). The majority (68%) of patients with PH had left heart failure, and 29% had lung disease. In-hospital mortality occurred in 8.3% and was more frequent in patients with PH [10.9% vs. 4.2%, adjusted odds ratio (OR) 1.40, 95% confidence interval (CI) 1.03-1.92, P = 0.03], particularly patients with moderate-to-severe PH (14.4% vs. 6.2%, adjusted OR 1.65, 95% CI 1.27-2.14, P < 0.001). In-hospital mortality increased incrementally as a function of higher RVSP (adjusted 1.18 per 10 mmHg increase, 95% CI 1.09-1.28, P < 0.001). Patients with higher RVSP or moderate-to-severe PH had increased in-hospital mortality across admission diagnoses (all P < 0.05).

Conclusions: Pulmonary hypertension is very common in the CICU population and appears to be independently associated with a higher risk of death during hospitalization, although the strength of this association varies according to the underlying admission diagnosis. These data highlight the importance of PH in patients with cardiac critical illness.