Long term survival of patients with raised pulmonary arterial systolic pressure utilizing echocardiography-a five-year prospective study

Abstract

Background: Pulmonary arterial systolic pressure (PASP) can be estimated with transthoracic echocardiography. However, the significance of raised PASP on routine echocardiography is uncertain. In this study, we evaluated the mortality and hospitalization rates of subjects with raised PASP in a cohort of patients referred directly by their general practitioners for routine outpatient (open access) echocardiography for further analysis of suspected heart failure.

Results: A total of 485 subjects were referred for open access echocardiography at our hospital in 2002. A cohort of 209/485 (43%) consecutive subjects with measurable tricuspid regurgitation were followed for a minimum of five years investigating hospitalization rates and survival. Some 62 of 209 (30%) subjects had pulmonary hypertension (PH). Subjects with PH were significantly more likely to have four or more hospital admissions (22% vs. 8%; P < 0.01) and > 30 days of cumulative hospital stay over five years (29% vs. 13%; P < 0.01). PH was significantly associated with mortality (P = 0.003), while moderate to severe PH was an independent predictor of mortality (hazard ratio: 4.31; 95% confidence interval (95% CI): 1.51-12.30). Records from the Office of National Statistics revealed that subjects with PH were more likely to have chronic lung diseases recorded as immediate or contributory causes of death (50% vs. 14%; P < 0.05).

Conclusions: PASP ≥ 36 mmHg on routine echocardiography is associated with recurrent hospital admissions, prolonged hospitalizations and increased cause of mortality. Therefore, the diagnosis of PH on echocardiography deserves further clinical evaluation, with future studies designed at defining a suitable diagnostic strategy.

Keywords: Chronic lung disease; Dyspnoea; Heart failure; Pulmonary hypertension; Transthoracic echocardiography.

Figures

Figure 1.. Outcomes for patients with measureable tricuspid regurgitation.

Flowchart demonstrating the echocardiographic outcomes of subjects investigated with routine outpatient echocardiography. *one subject untraceable. PASP: pulmonary arterial systolic pressure; TR: tricuspid regurgitation; TTE: transthoracic echocardiography; TTPG: transtricuspid pressure gradient.

Figure 2.. Survival in individuals with and without PH.

Kaplan-Meier survival plot of individuals with PH compared to individuals without PH. Overall survival in individuals with PH was significantly lower (P = 0.003).

Figure 3.. Survival plot for raised pulmonary arterial pressure by severity.

Cox regression survival plot for individuals with normal pulmonary arterial systolic pressure, mild pulmonary hypertension (PH), and moderate to severe PH, following adjustment for age, gender and presence of systemic hypertension. Moderate to severe PH was significantly associated with increased mortality (P = 0.006), while there was no significant difference in mortality between mild PH and no PH (P = 0.172).