Search

Pulmonary arterial hypertension (PAH) is a disease of the pulmonary vasculature characterized by vasoconstriction and vascular remodeling leading to a progressive increase in pulmonary vascular resistance (PVR). It is becoming increasingly recognized that it is the response of the right ventricle (RV) to the increased afterload resulting from this increase in PVR that is the most important determinant of patient outcome. A range of hemodynamic, structural, and functional measures associated with the RV have been found to have prognostic importance in PAH and, therefore, have potential value as parameters for the evaluation and follow-up of patients. If such measures are to be used clinically, there is a need for simple, reproducible, accurate, easy-to-use, and noninvasive methods to assess them. Cardiac magnetic resonance imaging (CMRI) is regarded as the “gold standard” method for assessment of the RV, the complex structure of which makes accurate assessment by 2-dimensional methods, such as echocardiography, challenging. However, the majority of data concerning the use of CMRI in PAH have come from studies evaluating a variety of different measures and using different techniques and protocols, and there is a clear need for the development of standardized methodology if CMRI is to be established in the routine assessment of patients with PAH. Should such standards be developed, it seems likely that CMRI will become an important method for the noninvasive assessment and monitoring of patients with PAH. [Copyright &y& Elsevier]

In pulmonary hypertension, exercise is limited by an impaired right ventricular (RV) stroke volume response. We hypothesized that improvement in exercise capacity after pulmonary endarterectomy (PEA) for chronic thromboembolic pulmonary hypertension (CTEPH) is paralleled by an improved RV stroke volume response. We studied the extent of PEA-induced restoration of RV stroke volume index (SVI) response to exercise using cardiac magnetic resonance imaging (cMRI). Patients with CTEPH (n = 18) and 7 healthy volunteers were included. Cardiopulmonary exercise testing and cMRI were performed before and 1 year after PEA. For cMRI studies, pre- and post-operatively, all patients exercised at 40% of their preoperative cardiopulmonary exercise testingeassessed maximal workload. Post-PEA patients (n = 13) also exercised at 40% of their postoperative maximal workload. Control subjects exercised at 40%of their predicted maximal workload. Preoperatively, SVI (n[18) decreased during exercise from 35.9 ± 7.4 to 33.0 ± 9.0 ml.m² (p = 0.023); in the control subjects, SVI increased (46.6 ± 7.6 vs 57.9 ± 11.8 ml.mL², p[0.001). After PEA, the SVI response (DSVI) improved from L2.8 ± 4.6 to 4.0 ± 4.6 ml.m² (p <0.001; n = 17). On exercise at 40% of the postoperativemaximal workload, SVI did not increase further and was still significantly lower compared with controls. Moreover, 4 patients retained a negative SVI response, despite (near) normalization of their pulmonary hemodynamics. The improvement in SVI response was accompanied by an increased exercise tolerance and restoration of RV remodeling. In conclusion, in CTEPH, exercise is limited by an impaired stroke volume response. PEAinduces a restoration ofSVI response to exercise that appears, however, incomplete and not evident in all patients. [ABSTRACT FROM AUTHOR]

Previous studies have shown the prognostic benefit of N-terminal pro–brain natriuretic peptide (NT–pro-BNP) in pulmonary arterial hypertension (PAH) at time of diagnosis. However, there are only limited data on the clinical utility of serial measurements of the inactive peptide NT–pro-BNP in PAH. This study examined the value of serial NT–pro-BNP measurements in predicting prognosis PAH. We retrospectively analyzed all available NT–pro-BNP plasma samples in 198 patients who were diagnosed with World Health Organization group I PAH from January 2002 through January 2009. At time of diagnosis median NT–pro-BNP levels were significantly different between survivors (610 pg/ml, range 6 to 8,714) and nonsurvivors (2,609 pg/ml, range 28 to 9,828, p <0.001). In addition, NT–pro-BNP was significantly associated (p <0.001) with other parameters of disease severity (6-minute walking distance, functional class). Receiver operating curve analysis identified ≥1,256 pg/ml as the optimal NT–pro-BNP cutoff for predicting mortality at time of diagnosis. Serial measurements allowed calculation of baseline NT–pro-BNP (i.e., intercept obtained by back-extrapolation of concentration–time graph), providing a better discrimination between survivors and nonsurvivors than NT–pro-BNP at time of diagnosis alone (p = 0.010). Furthermore, a decrease of NT–pro-BNP of >15%/year was associated with survival. In conclusion, a serum NT–pro-BNP level ≥1,256 pg/ml at time of diagnosis identifies poor outcome in patients with PAH. In addition, a decrease in NT–pro-BNP of >15%/year is associated with survival in PAH. [ABSTRACT FROM AUTHOR]

Heart rate (HR) at rest is an important marker of prognosis in heart failure, but has not been addressed in pulmonary arterial hypertension (PAH). To determine the prognostic value of HR at rest in patients with PAH, we retrospectively analyzed 140 consecutive patients with idiopathic PAH. Electrocardiogram (ECG)-derived HR at rest was evaluated as a potential predictor of adverse prognosis (death or lung transplantation), in addition to World Health Organization functional class, 6-minute walk distance, and hemodynamics before and approximately 1 year and 2 years after initiation of PAH treatment. During follow-up, 49 patients (35%) died, and 5 patients (4%) underwent lung transplantation. Before treatment initiation and after 1 year and 2 years of treatment, respectively, a higher HR at rest was an independent predictor of adverse prognosis (hazard ratios per 10-beats/min increase 1.76, 95% confidence interval 1.42 to 2.18, 2.31, 95% confidence interval 1.58 to 3.38, 2.1, 95% confidence interval 1.39 to 3.19, respectively, p <0.001 for all). Change in HR between the first and last ECG also independently predicted prognosis (hazard ratio per 1-beat/min increase 1.03, 95% confidence interval 1.01 to 1.06). In conclusion, a higher HR at rest and an important increase in HR at rest during follow-up signify a considerable risk of death in patients with PAH. ECG-derived HR at rest is an important marker of prognosis and should be assessed before and at frequent intervals after initiation of treatment for PAH. [Copyright &y& Elsevier]