ABSTRACT
Background: The upper physiological threshold for tricuspid regurgitation velocity (TRV) of 2.8 m/s proposed by the Pulmonary Hypertension (PH) guidelines had been questioned. The aim of this study was to evaluate the prognostic significance of preoperative PH in patients with aortic stenosis, long-term after valve replacement, using two different TRV thresholds (2.55 and 2.8 m/s). Methods: Four hundred and forty four patients were included (mean age 73 ± 9 years; 55% male), with a median follow-up of 5.8 years (98% completed). Patients were divided into three PH probability groups according to guidelines (low, intermediate and high) for both thresholds (TRV ≤ 2.8 m/s and TRV ≤ 2.55 m/s), using right atrial area>18 cm2 and right ventricle/left ventricle ratio>1 as additional echocardiographic variables. Results: In patients with measurable TRV (n = 304), the low group mortality rate was 25% and 30%, respectively for 2.55 and 2.8 m/s TRV thresholds. The intermediate group with TRV > 2.55 m/s was an independent mortality risk factor (HR 2.04; 95% CI: 1.91 to 3.48, p = 0.01), in contrast to the intermediate group with TRV>2.8 m/s (HR 1.44; 95% CI: 0.89 to 2.32, p = 0.14). Both high probability groups were associated with an increased mortality risk, as compared to their respective low groups. When including all patients (with measurable and non-measurable TRV), both intermediate groups remained independently associated with an increased mortality risk: HR 1.62 (95% CI 1.11 to 2.35 p = 0.01) for the new cut-off point; and HR 1.43 (95% CI: 0.96 to 2.13, p = 0.07) for guidelines threshold. Conclusion: A TRV threshold of 2.55 m/s, together with right cavities measures, allowed a better risk assessment of patients with PH secondary to severe aortic stenosis, with or without tricuspid regurgitation.
ABSTRACT
BACKGROUND: Severe pulmonary hypertension (PH) in patients with aortic stenosis is related to poor prognosis following aortic valve replacement (AVR). Current European PH guidelines recommend adding two different echocardiographic signs to tricuspid regurgitation velocity (TRV) in PH estimation, classifying its probability as low (TRV ≤ 2.8 m/s), intermediate (TRV 2.9-3.4 m/s), and high (TRV > 3.4 m/s). The right ventricle is an important determinant of prognosis in PH. The goal of this study was to analyze the value of right atrial area > 18 cm2 and right ventricular/left ventricular ratio > 1 in the long-term prognosis following AVR, mainly in the intermediate probability group. METHODS: This study included 429 consecutive patients (mean age, 73 ± 8 years; 55% male) with a median follow-up of 4.25 years (completed in 98%). Patients were divided into low (n = 247), intermediate (n = 117), and high probability groups (n = 65). The intermediate probability group was divided into two subgroups: subgroup 2a (n = 27; TRV nonmeasurable or ≤ 2.8 m/s and two signs present) and subgroup 2b (n = 90; TRV 2.9-3.4 m/s, and none or only one sign present). RESULTS: Overall mortality rates during follow-up of the low, intermediate, and high probability groups were 24%, 32%, and 42%, respectively. High PH probability was an independent predictor of all-cause mortality (hazard ratio [HR], 1.82; 95% CI, 1.11-3.00), but the intermediate probability group did not reach significance following multivariate analysis (HR, 1.40; 95% CI, 0.91-2.16). When the intermediate probability group was divided into subgroups, the subgroup 2a mortality rate (56%) was higher than that of both subgroup 2b (24%; P = .002) and the low probability group (24%; P < .001). Following multivariate analysis, subgroup 2a showed a significantly higher mortality (HR, 2.13; 95% CI, 1.11-4.10) in contrast to subgroup 2b (HR, 1.24; 95% CI, 0.75-2.05), both compared with the low probability group. CONCLUSIONS: Incorporating measurement of the right cavities into the PH probability model in the assessment of long-term prognosis following AVR allowed better risk discrimination, especially in the intermediate probability group.
