Mode of death in patients with pulmonary arterial hypertension

Abstract

Purpose: Right ventricular failure is considered the most frequent mode of death in pulmonary arterial hypertension (PAH), but it is a common clinical experience that PAH patients often die suddenly (SD) or following an acute illness. Methods: We conduced a retrospective analysis of 202 consecutive PAH patients. According to the ACME classification, mode of death was classified as due to right heart failure (RHF), SD and triggered by extra cardiac cause (ExC). Results: After a mean follow-up of 885±890 days, we observed 71 deaths (35%). The actuarial survival rate was 80%, 71%, 60% and 58% at 1, 2, 3 and 4 years, respectively. RHF was observed in 43 (60%), SD in 9 (13%) and ExC in 19 (27%) patients. RHF goup showed a trend towards longer survival compared to the others, and had a higher NYHA class (RHF 3.0±0.6, SD 2.7±0.5, ExC 2.8±0.6; p ns) and a lower effort tolerance (6-minute walk distance: RHF 296±107 m, SD 393±84 m, ExC 362±114 m; p<0.001) and cardiac index (RHF 2.0±0.7 l/min/m2, SD 2.2±0.7 l/min/m2, ExC 2.3±0.8 l/min/m2; p<0.05). SD or ExC patients had a similar clinical and hemodynamic profile of survivors, and ExC group had a lower body mass index (BMI: RHF 24±5 kg/m2, SD 24±5 kg/m2, ExC 21±4 kg/m2; p<0.03). View this table: Comparison among the four groups Conclusions: Death in PAH is not exclusively due to refractory RHF, as SD and ExC could account for about 40% of the overall deaths. The findings that these latter groups have a hemodynamic profile similar to survivors should be confirmed in a larger population. Further prospective multicenter study is needed in order to better define the modality of death in PAH, and analyse specific risk factors for SD and ExC.